JP6697036B2 - Point-to-point wireless device and communication control method - Google Patents

Description

  The present invention relates to a point-to-point wireless device and a communication control method, and more particularly to a point-to-point wireless device and a communication control method for performing multicarrier transmission using a spectrum mask for single carrier transmission.

  Patent Documents 1 and 2 disclose examples of fixed type point-to-point wireless communication systems in which a communication partner for wireless communication is set (fixed).

  A fixed point-to-point wireless communication system uses a frequency division duplexing (FDD) method for two-way simultaneous communication (full-duplex communication). By using the FDD method, a pair of wireless devices facing each other on a point-to-point wireless line suppresses mutual frequency interference by dividing the wireless frequency band used in the up direction and the down direction. Therefore, mutual communication can be efficiently performed.

  Here, it is assumed that one device of a pair of wireless devices facing each other on a point-to-point wireless line is referred to as a wireless device A and the other device is referred to as a wireless device B. In the FDD system, the frequency of the radio wave transmitting a signal from the wireless device A to the wireless device B and the frequency of the radio wave transmitting a signal from the wireless device B to the wireless device A are different from each other. Therefore, the transmission of a signal from the wireless device A to the wireless device B and the opposite transmission of the signal from the wireless device B to the wireless device A can be simultaneously performed without causing frequency interference between them. ..

  By the way, normally, when the wireless device A and the wireless device B perform wireless communication by the point-to-point FDD method, radio waves in the up and down wireless frequency bands used by the wireless device A and the wireless device B for communication are transmitted. Obtain a license for use in pairs. Further, the frequency interval between the frequency of the radio wave transmitted from the radio device A to the radio device B and the frequency of the radio wave transmitted from the radio device B to the radio device A is regulated by the radio frequency standard of each country. The communication settings are set by the center frequency, bandwidth, and modulation / demodulation method, which is called a carrier.

  A device that wirelessly transmits data to be transmitted by one carrier is called a single carrier transmission wireless device, and a device that simultaneously transmits a plurality of carriers is called a multicarrier transmission wireless device.

  For example, in the case of an FDD single-carrier transmission wireless device, wireless device A transmits to wireless device B by a single carrier determined by the center frequency, bandwidth, and modulation method, and at the same time, wireless device B to wireless device A makes a certain decision. Transmission is performed with a single carrier that maintains the specified frequency interval. At this time, the frequency interval of radio waves that can be used for a single carrier that is wirelessly transmitted together is specified by, for example, ITU-R (International Telecommunication Union Radio communications sector).

  Further, from the viewpoint of effective use of frequencies in a wireless communication system and constant protection of adjacent wireless frequency bands, a spectrum mask that defines an allowable range of a wireless transmission spectrum of a carrier is provided. Then, the wireless device must suppress the unnecessary radiation of the output of the transmitter and perform the transmission control of the carrier that fits within the spectrum mask. A spectrum mask that defines a permissible range of a radio transmission spectrum of a carrier used in a fixed point-to-point radio apparatus is standardized by ETSI (European Telecommunications Standards Institute). See, for example, Section 4.2.4 of Non-Patent Document 1.

  Note that Patent Document 1 efficiently searches an unused wireless channel that can obtain good wireless quality when switching a wireless link in which a failure has occurred in a point-to-point wireless system using microwaves or millimeter waves. Disclose the technology.

  Further, Patent Document 2 uses a redundant line for maintenance and control when recovering from one-way communication due to a failure in one wireless link when an FDD with a fixed frequency interval is used. A technique for safely switching between two-way used wireless channels without any is disclosed.

  Further, although it is not a fixed type point-to-point wireless communication system, Patent Document 3 discloses that wireless communication capable of adaptively communicating in an optimum wireless mode (single carrier transmission, multicarrier transmission) according to the state of the propagation path. A system is disclosed.

  Furthermore, Patent Document 4 discloses a multi-carrier communication device capable of ensuring communication reliability in an environment in which an interference wave exists. This communication device sets the transmission frequency band based on the noise level of each subcarrier, excluding the subcarriers existing in the frequency band in which the interference wave exists. Then, at the time of reception, the usable frequency band is selected from the respective pass frequency bands of the bandpass filter, and any one frequency band is designated as the frequency band used at the time of reception.

  The communication devices disclosed in Patent Document 3 and Patent Document 4 are wireless devices using the OFDM (Orthogonal Frequency Division Multiplexing) method.

JP, 2005-177497, A JP, 2005-177498, A JP 2012-192425 A JP, 2010-004469, A

ETSI EN 302 217-2-2 V2.1.1 (2013-07), Fixed Radio Systems; Characteristics and requirements for point-to-point equipment and antennas; Part 2-2: Digital systems operating in frequency bands where frequency co-ordination is applied; Harmonized EN covering the essential requirements of article 3.2 of the R & TTE Directive

  Fixed point-to-point wireless devices are devices that are mainly licensed for single carrier transmission. The fixed point-to-point wireless device is hereinafter referred to as a point-to-point wireless device.

  When a point-to-point wireless device licensed for single carrier transmission is shared by a plurality of users, the data of each user is multiplexed and then wirelessly transmitted using a single carrier.

  In the case of single-carrier transmission, if fading or adjacent channel interference occurs on the propagation path for a single carrier in which multiple user data are multiplexed, the effects such as deterioration of transmission quality and communication disconnection on all users are affected. Will affect. Further, some users may want to increase the transmission capacity for the channel to be used and some may want to ensure the transmission quality, and the point-to-point wireless device using single carrier transmission cannot simultaneously satisfy the needs of different users.

  The ETSI EN302 217-2-2 standard of Non-Patent Document 1 is a standard relating to a spectrum mask that defines a wireless transmission spectrum of single carrier transmission by such a point-to-point wireless device.

  In recent years, the ETSI EN302 217-2-2 standard has added a standard for using a spectrum mask defined for conventional single carrier transmission in multicarrier transmission. This adds a regulation for converting a single carrier transmission into a multicarrier so as not to affect the existing transmission. As a result, the ETSI EN302 217-2-2 standard applied to a point-to-point wireless device can also provide a wireless device that uses a wireless frequency band in multicarrier transmission.

  In the ETSI EN302 217-2-2 standard, the spectrum mask defined in the conventional radio transmission spectrum during single carrier transmission is also applied to the radio transmission spectrum during multicarrier transmission. For example, in the case of multicarrier transmission using two subcarriers, it is required to adjust the transmission level deviation between the two subcarriers within a predetermined value or to adjust the bandwidth so that it falls within the side mask. There is. That is, in converting a single-carrier transmission point-to-point wireless device into multi-carrier transmission, it is necessary to satisfy the wireless transmission spectrum regulation for single-carrier transmission and perform multi-carrier transmission.

  However, the ETSI EN302 217-2-2 standard only clarifies the radio transmission spectrum regulation when converting a point-to-point radio apparatus into multicarrier transmission, and there is no disclosure regarding a concrete realization means thereof. Therefore, it is desired to develop a point-to-point wireless device capable of multicarrier transmission by adjusting the transmission output level and bandwidth for each subcarrier for multicarrier transmission and satisfying the radio transmission spectrum regulation for single carrier transmission. ..

  Patent Literature 1 and Patent Literature 2 disclose a technique related to a point-to-point wireless system, but there is no disclosure related to a point-to-point wireless device capable of performing multi-carrier transmission while satisfying a wireless transmission spectrum regulation at the time of single-carrier transmission.

  Further, although Patent Documents 3 and 4 disclose techniques related to multi-carrier communication devices, both are techniques based on the OFDM scheme. Therefore, these Patent Documents 3 and 4 also do not disclose a point-to-point radio apparatus that can perform multicarrier transmission while satisfying the radio transmission spectrum regulation for single carrier transmission.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a point-to-point wireless apparatus and a communication control method capable of performing multi-carrier transmission while satisfying a radio transmission spectrum regulation at the time of single-carrier transmission. Especially.

  In order to achieve the above object, a point-to-point radio apparatus according to an aspect of the present invention can be arranged in accordance with a predetermined single carrier transmission radio transmission spectrum regulation according to the number of subcarriers for multicarrier transmission. A subcarrier generating unit that generates a subcarrier converted into a modulated wave of a modulation intermediate frequency band having a center frequency and a bandwidth, corresponds to each subcarrier that performs multicarrier transmission, and the subcarrier generating unit outputs the subcarrier. Level increase / decrease calculation means for instructing the subcarrier generation means to increase / decrease the signal level of the modulated wave so that the signal level of the subcarrier satisfies the predetermined radio transmission spectrum regulation of the single carrier transmission. And a multicarrier synthesizing means for synthesizing into multicarriers, frequency-converting into a radio intermediate frequency band, and outputting when the respective signal levels of the subcarriers satisfy the radio transmission spectrum regulation, and the multicarrier synthesizing means. Is included in the wireless intermediate frequency band, and the wireless multi-carrier is converted into a transmission signal in the wireless frequency band and is output.

  A communication control method according to another aspect of the present invention is a modulation method having a center frequency and a bandwidth that can be arranged in accordance with the number of subcarriers for multicarrier transmission so as to satisfy a predetermined radio transmission spectrum specification for single carrier transmission. Generate subcarriers converted to modulated waves in the intermediate frequency band, so that each signal level of the subcarriers for multicarrier transmission satisfies the radio transmission spectrum regulation of the predetermined single carrier transmission held in advance. Instructing to increase / decrease the signal level of the modulated wave, and when each signal level of the subcarriers satisfies the radio transmission spectrum regulation, the signals are combined into multicarriers, frequency-converted to a radio intermediate frequency band, and output. The multi-carrier in the radio intermediate frequency band is converted into a transmission signal in the radio frequency band and output.

  INDUSTRIAL APPLICABILITY The present invention can provide a point-to-point radio apparatus and a communication control method capable of performing multicarrier transmission while satisfying the radio transmission spectrum regulation for single carrier transmission.

It is a block diagram which illustrates the composition of the point-to-point radio equipment concerning the 1st embodiment of the present invention. It is a flowchart which illustrates operation | movement of the communication control method which concerns on the 1st Embodiment of this invention. It is a block diagram which illustrates the structure of the point-to-point radio | wireless apparatus which concerns on the 2nd Embodiment of this invention. It is a block diagram which illustrates the composition by the side of the transmission of the multicarrier control part which constitutes a point-to-point radio equipment. It is a block diagram which illustrates the composition by the side of the receiving of the multicarrier control part which constitutes a point-to-point radio equipment. It is a figure which illustrates the radio transmission spectrum for demonstrating the difference of single carrier transmission and multicarrier transmission. It is a figure explaining the transmission level deviation between the subcarriers in the radio transmission spectrum by the ETSI standard. It is a flowchart explaining the whole operation | movement of increase / decrease control of the signal level of the subcarrier which carries out multicarrier transmission. FIG. 9 is a flow chart illustrating an operation of increasing / decreasing an output level of a modulated wave amplifier so as to satisfy a standard radio transmission spectrum regulation in the operation of FIG. 8.

  Embodiments for carrying out the present invention will be described in detail below with reference to the drawings.

  Note that the embodiments are mere examples, and the disclosed apparatus and method are not limited to the configurations of the following embodiments. Further, the reference numerals attached to the drawings are added for convenience as an example for facilitating understanding, and are not intended to be limited in any way. Furthermore, the directions of the arrows in the drawings show examples, and do not limit the directions of signals between blocks.

(First embodiment)
A first embodiment will be described with reference to FIGS. 1 and 2.

  FIG. 1 is a block diagram illustrating the configuration of a point-to-point wireless device according to the first embodiment of the present invention.

  The point-to-point radio apparatus 10 according to the first embodiment includes a subcarrier generation unit 11, a level increase / decrease calculation unit 12, a multicarrier combination unit 13, and a radio transmission unit 14 corresponding to each subcarrier for multicarrier transmission. It has become.

  The subcarrier generation means 11 converts into a modulated wave of a modulation intermediate frequency band having a center frequency and a bandwidth that can be arranged so as to satisfy a predetermined radio transmission spectrum regulation of single carrier transmission according to the number of subcarriers for multicarrier transmission. Generate subcarriers.

  The level increase / decrease calculation means 12 makes the subcarrier generation means 11 so that the signal level of the subcarrier output from each of the subcarrier generation means 11 satisfies a predetermined radio transmission spectrum regulation of single carrier transmission held in advance. Instruct to increase or decrease the signal level of the modulated wave.

  When the signal levels of the subcarriers satisfy the radio transmission spectrum regulation, the multicarrier synthesizing unit 13 synthesizes the multicarriers, frequency-converts them into a radio intermediate frequency band, and outputs the result.

  The wireless transmission unit 14 converts the multi-carrier in the wireless intermediate frequency band output from the multi-carrier combining unit 13 into a transmission signal in the wireless frequency band and outputs the signal.

  The wireless intermediate frequency band is also referred to as an IF (Intermediate Frequency) band, and the wireless frequency band is also referred to as an RF (Radio Frequency) band.

  With the above configuration, when the subcarriers output by each subcarrier generation unit 11 are combined into multicarriers, the signal spectrum thereof can satisfy the prescribed radio transmission spectrum for single carrier transmission. .. Therefore, the point-to-point wireless device 10 of the present embodiment functions as a point-to-point wireless device capable of performing multi-carrier transmission while satisfying the wireless transmission spectrum regulation for single carrier transmission.

  FIG. 2 is a flowchart illustrating the operation of the communication control method according to the first embodiment of the present invention. In the communication control method according to the first embodiment, the point-to-point wireless device operates as follows.

  A subcarrier converted into a modulated wave in the modulated intermediate frequency band is generated. At this time, a center frequency and a bandwidth that can be arranged so as to satisfy the predetermined radio transmission spectrum regulation of single carrier transmission are set to the subcarriers according to the number of subcarriers to be multicarrier transmitted (S101).

  The increase / decrease control of the signal level of the modulated wave is performed so that the signal level of each subcarrier for multicarrier transmission satisfies the predetermined radio transmission spectrum regulation of single carrier transmission that is held in advance (S102).

  When each signal level of the subcarriers satisfies the radio transmission spectrum regulation, the subcarriers are combined into multicarriers, frequency-converted into a radio intermediate frequency band, and output (S103).

  The multi-carrier in the wireless intermediate frequency band is converted into a transmission signal in the wireless frequency band and output (S104).

  By operating as described above, when the subcarriers are combined into multicarriers, the signal spectrum thereof can satisfy the prescribed radio transmission spectrum for single carrier transmission. Therefore, the communication control method of the present embodiment can provide a communication control method capable of performing multicarrier transmission while satisfying the radio transmission spectrum regulation during single carrier transmission.

(Second embodiment)
The second embodiment will be described in detail with reference to FIGS. 3 to 9.

[Description of configuration]
FIG. 3 is a block diagram illustrating the configuration of a point-to-point wireless device according to the second embodiment of the present invention.

  The point-to-point wireless device 20 according to the second embodiment is exemplified by a microwave relay device that uses a microwave or a millimeter wave to establish a wireless link with an opposing wireless device. In addition, the point-to-point wireless device 20 uses the FDD system in order to perform bidirectional simultaneous communication (full-duplex communication) with the opposing wireless device. In the FDD system, in order to suppress interference due to wraparound between transmission and reception of radio frequencies, a fixed frequency interval is maintained between the radio transmission frequency and the radio reception frequency.

  The point-to-point wireless device 20 includes an interface unit 21, a multicarrier control unit 22, and a wireless transceiver 23.

  The interface unit 21 converts a signal in a data format of a user-side device standard, which is input from a user-side device (not shown), into a baseband signal (unipolar 0/1 data) handled by the wireless device. Conversely, the baseband signal handled by the wireless device is converted into a signal in the data format of the user-side device standard output to the user-side device. For example, when the user side device and the point-to-point wireless device 20 are connected by a LAN (Local Area Network), the signal of the data format of the user side device standard is a signal of the LAN standard.

  At the time of transmission, the multicarrier control unit 22 individually modulates the user signal corresponding to each subcarrier for multicarrier transmission, frequency-converts it into a modulated signal in the modulation intermediate frequency band, and performs signal increase / decrease processing to change the subcarriers. To generate. The multicarrier control unit 22 combines the generated plurality of subcarriers into a transmission signal in a multicarrier transmission form. Then, the transmission signal combined in the multi-carrier transmission form is frequency-converted into a transmission signal (Txif) in the wireless intermediate frequency band (IF band) and output to the wireless transceiver 23.

  When receiving, the multicarrier control unit 22 frequency-converts the IF band received signal (Rxif) in the multicarrier transmission form input from the wireless transceiver 23 into a demodulated intermediate frequency band received signal. Then, the received signal is separated into subcarriers, and the separated subcarriers are individually demodulated to output a received signal in the baseband.

  At the time of transmission, the multi-carrier control unit 22 performs waveform shaping so that, when each sub-carrier is individually generated, the combined transmission signal of the multi-carrier transmission form fits within the spectrum mask defined by the ETSI standard.

  At the time of transmission, the wireless transceiver 23 transmits the transmission signal (Txif) in the IF band output by the multi-carrier control unit 22 through a wireless channel in the wireless frequency band (RF band) for which the license is designated (Txrf). ). Then, the transmission signal (Txrf) is wirelessly transmitted to the opposite wireless device via the antenna.

  On the other hand, at the time of reception, the wireless transceiver 23 receives the reception signal (Rxrf) in the RF band on the wireless channel of the receiving side, which is licensed as a pair. Then, it corrects the reception level fluctuations caused by environmental fluctuations such as radio space fluctuations and rainfall, and then converts the reception level fluctuations into IF band reception signals (Rxif), which are output to the multicarrier control unit 22.

  As described above, in the point-to-point radio apparatus 20 of the present embodiment, the multicarrier control unit 22 performs frequency conversion between the baseband band and the modulation / demodulation intermediate frequency band, and the modulation / demodulation intermediate frequency band. Frequency conversion to and from the IF band is performed. Then, in the wireless transceiver 23, frequency conversion between the IF band and the RF band is performed. Here, the subcarrier corresponding to the transmission signal of the user is waveform-shaped and synthesized in the modulation intermediate frequency band so as to be included in the spectrum mask that defines the allowable range of the radio transmission spectrum transmitted in the RF band.

  The subcarrier generation unit 11, the level increase / decrease calculation unit 12, and the multicarrier combination unit 13 of the first embodiment correspond to the multicarrier control unit 22 of the second embodiment. In particular, in FIG. 4 described later, the subcarrier unit 221 corresponds to the subcarrier generation unit 11, and the reference value storage unit 2231 and the level increase / decrease calculation unit 2232 in the common control unit 223 correspond to the level increase / decrease calculation unit 12. The combiner 2233 and the IF band frequency converter 2234 in the common controller 223 correspond to the multicarrier combiner 13. The wireless transmission means 14 of the first embodiment corresponds to the wireless transceiver 23 of the second embodiment.

  The point-to-point radio apparatus 20 shown in FIG. 3 illustrates a case where two user signals of user A and user B are multi-carrier transmitted. Here, it is assumed that the transmission signal of user A is transmission signal aT and the transmission signal of user B is transmission signal bT. Further, the received signal of the user A is referred to as a received signal aR, and the received signal of the user B is referred to as a received signal bR.

  4 and 5 are block diagrams each illustrating the configuration of the multicarrier control unit 22, FIG. 4 shows the configuration of the transmitting side, and FIG. 5 shows the configuration of the receiving side.

  The multi-carrier control unit 22 includes a sub-carrier unit that performs processing on each sub-carrier that performs multi-carrier transmission, and a common control unit 223 that commonly controls each sub-carrier unit.

  Here, since two user signals of user A and user B are multi-carrier transmitted, it is configured to include a subcarrier unit a221 that processes the signal of user A and a subcarrier unit b222 that processes the signal of user B. ..

  That is, FIG. 4 shows a configuration in which the subcarrier unit a221 processes the subcarrier for the transmission signal aT of the user A, and the subcarrier unit b222 processes the subcarrier for the transmission signal bT of the user B. Further, FIG. 5 shows a configuration in which the subcarrier unit a221 processes the subcarrier for the received signal aR of the user A, and the subcarrier unit b222 processes the subcarrier for the received signal bR of the user B.

  In FIG. 4, the common control unit 223 adjusts the signal level of the subcarriers that are individually modulated by the subcarrier unit a221 and the subcarrier unit b222, and the radio transmission and reception by combining the signal level-adjusted subcarriers. The configuration for outputting to the machine 23 is shown. The combined transmission signal of the multi-carrier transmission form is converted into an IF band frequency and output to the wireless transceiver 23.

  Further, FIG. 5 shows a configuration in which the common control unit 223 inputs a signal in the IF band from the wireless transceiver 23 and distributes it to the subcarrier unit a221 and the subcarrier unit b222 as a reception signal in the demodulation intermediate frequency band.

  The configuration of the multicarrier control unit 22 will be described in detail with reference to FIGS. 4 and 5.

  Referring to FIG. 4, the subcarrier unit a221 inputs the transmission signal aT of the user A, and the subcarrier unit b222 inputs the transmission signal bT of the user B, and each of them individually modulates the signal, shapes the waveform, and outputs Level adjustment is performed to generate subcarriers.

  The configuration will be described with reference to the subcarrier portion a221.

  The subcarrier unit a221 includes a modulation unit 2211, a modulation wave frequency conversion unit 2212, a modulation wave amplifier 2213, and a detector 2214.

  The modulation unit 2211 receives the transmission signal aT (baseband signal) of the user A output from the interface unit 21 which is the device at the previous stage shown in FIG. 3, and modulates it by a predetermined modulation method to obtain a modulated signal as an analog signal. Is output.

  The modulation unit 2211 is configured so that a modulation method according to a user's request can be appropriately selected and set. For example, a 4PSK (Quadrature Phase Shift Keying) method or a QAM (Quadrature Amplitude Modulation) method can be selected. In the case of the QAM system, 16QAM / 32QAM / 64QAM / 128QAM / 256QAM / 1024QAM / 2048QAM can be selected according to the number of modulation levels. Further, the information may be fed back to the transmitting side according to the receiving state on the receiving side, and adaptive modulation for adaptively changing the modulation system may be possible.

  The modulated wave frequency conversion unit 2212 is composed of a frequency conversion circuit and a bandpass filter, and waveform-shapes the modulated signal into a modulated wave of a modulation intermediate frequency band having a predetermined center frequency and bandwidth. In FIG. 4, the center frequency is set to f1.

  The modulated wave amplifier 2213 increases or decreases the signal level of the waveform-shaped modulated wave output from the modulated wave frequency converter 2212. Here, the output level of the modulated wave amplifier 2213 is controlled to increase or decrease based on the instruction value from the common control unit 223, as described later, so that the subcarriers satisfy the predetermined radio transmission spectrum regulation.

  The detector 2214 measures the signal level of the modulated wave output from the modulated wave amplifier 2213 and outputs it to the common control unit 223.

  Although the above is the configuration of the subcarrier unit a221, the subcarrier unit b222 has the same configuration. That is, the subcarrier unit b222 includes a modulation unit 2221, a modulation wave frequency conversion unit 2222, a modulation wave amplifier 2223, and a detector 2224.

  The subcarrier unit b222 inputs the transmission signal bT of the user B and generates a subcarrier for the user B. Therefore, the modulation unit 2221 appropriately selects and sets the modulation method according to the request of the user B. The modulated wave frequency conversion unit 2222 shapes the waveform as a modulated wave having a center frequency of f2 and a predetermined bandwidth.

  The modulation wave amplifier 2223 controls the signal level of the waveform-shaped modulation wave output from the modulation wave frequency conversion unit 2222, based on the instruction value from the common control unit 223.

  The detector 2224 measures the signal level of the modulated wave output from the modulated wave amplifier 2223 and outputs it to the common control unit 223.

  The waveform shaping executed by the modulated wave frequency conversion unit 2212 of the subcarrier unit a221 and the modulated wave frequency conversion unit 2222 of the subcarrier unit b222 is performed so that the combined modulated waves satisfy the predetermined radio transmission spectrum regulations. The frequency and bandwidth are set. This will be described later.

  The modulated waves output from the modulated wave amplifiers 2213 and 2223 will be referred to as subcarriers hereinafter.

  Next, the configuration of the common control unit 223 will be described.

  The common control unit 223 is configured to include a reference value storage unit 2231, a level increase / decrease calculation unit 2232, a combiner 2233, and an IF band frequency conversion unit 2234.

  The reference value storage unit 2231 and the level increase / decrease calculation unit 2232 are configured to output an instruction value for increasing / decreasing the output level of the modulated wave amplifier of each subcarrier unit. That is, an instruction value for increasing / decreasing the signal level of the corresponding subcarrier is output to each of the modulation wave amplifier 2213 of the subcarrier unit a221 and the modulation wave amplifier 2223 of the subcarrier unit b222.

  The reference value storage unit 2231 stores in advance information about a predetermined radio transmission spectrum regulation and information about a modulation method based on an operation contract condition with a user. In addition, the reference value storage unit 2231 inputs the signal level of the subcarriers whose increase / decrease is controlled by the modulation wave amplifier, which is measured by the detector of each subcarrier unit. That is, the signal levels of the subcarriers, which are the outputs of the modulation wave amplifier 2213 and the modulation wave amplifier 2223, which are respectively output from the detector 2214 of the subcarrier unit a221 and the detector 2224 of the subcarrier unit b222, are input.

  The level increase / decrease calculation unit 2232 calculates a signal increase / decrease level by verifying the difference between the information previously stored in the reference value storage unit 2231 and the signal level of each subcarrier input to the reference value storage unit 2231, and calculates the required modulation wave amplifier. The output level increase / decrease instruction is issued. That is, an instruction value for increasing / decreasing the signal level of a predetermined subcarrier is output to the modulation wave amplifier 2213 or the modulation wave amplifier 2223 so that the predetermined radio transmission spectrum regulation is satisfied when combined as multicarriers. ..

  This modulation wave amplifier, each detector, the reference value storage unit 2231, and the level increase / decrease calculation unit 2232 increase / decrease control of the signal level of the subcarriers are within the allowable value range in which the signal level of each subcarrier is defined in advance. Is repeated until the appropriate value is reached.

  When the level increase / decrease calculation unit 2232 determines that the signal level of each subcarrier has reached an appropriate value within a predetermined allowable value range, the subcarrier output from each modulated wave amplifier is output to the combiner 2233. Combined as multi-carrier. Further, at this time, the level increase / decrease calculation unit 2232 stores the signal level of each subcarrier that has reached an appropriate value in the reference value storage unit 2231.

  The synthesizer 2234 synthesizes each subcarrier whose signal level is within a predetermined allowable value range into a multicarrier, and the IF band frequency conversion section 2234 converts the multicarrier into an IF band frequency and outputs it.

  The synthesizer 2234 synthesizes the subcarriers output from the subcarrier unit a221 and the subcarrier unit b222, extracts only the effective component as data within the signal band after synthesis by a bandpass filter (not shown), and undesired waves are extracted. Performs waveform shaping to remove components.

  The IF band frequency conversion unit 2234 frequency-converts the combined multicarrier into an IF band transmission signal (Txif) using an f3 signal, and uses a bandpass filter (not shown) to perform an effective component within the signal band of the transmission signal (Txif). Only the unwanted wave component is removed by extracting only the signal.

  The transmission signal (Txif) output from the IF band frequency conversion unit 2234 is input to the wireless transceiver 23 shown in FIG. The wireless transceiver 23 converts the input signal into a transmission signal (Txrf) in the RF band for which a license is designated, and wirelessly transmits the signal to the opposite wireless device via the antenna.

  Next, the configuration of the receiving side of the multicarrier control unit 22 will be described with reference to FIG.

  The multi-carrier control unit 22 uses the common control unit 223 to convert the reception signal (Rxif) in the IF band into a reception signal in the demodulation intermediate frequency band, demultiplex each sub-carrier that has been multi-carrier transmitted, and output the corresponding sub-carrier. It is distributed to the carrier part a221 and the subcarrier part b222.

  The subcarrier unit a221 and the subcarrier unit b222 demodulate the corresponding subcarriers and output the received signal aR and the received signal bR in the baseband to the interface unit 21 shown in FIG.

  Referring to FIG. 5, the common controller 223 of the multi-carrier controller 22 includes an IF band frequency converter 2236 and a demultiplexer 2235.

  The IF band frequency conversion unit 2236 inputs the reception signal (Rxif) in the IF band of the multicarrier transmission form received from the wireless transceiver 23 shown in FIG. At this time, an effective component of the received signal (Rxif) is extracted by a bandpass filter (not shown), and unnecessary wave components are removed.

  The IF band frequency conversion unit 2236 converts the IF band reception signal (Rxif) into a demodulation intermediate frequency band reception signal by the f13 signal, and removes unnecessary waves generated by frequency conversion by a band pass filter (not shown).

  The demultiplexer 2235 demultiplexes the received signal in the demodulation intermediate frequency band generated by the IF band frequency conversion unit 2236 into each subcarrier that is multicarrier-transmitted, and distributes it to the corresponding subcarrier unit.

  The subcarrier unit a221 includes a BPF (bandpass filter) 2218, a demodulation wave amplifier 2217, a demodulation wave frequency conversion unit 2216, and a demodulation unit 2215.

  From the demodulation subcarriers (demodulation waves) input to the subcarrier unit a221, the corresponding demodulation wave signal is extracted by the BPF 2218, and the demodulation wave amplifier 2217 amplifies the signal level of the demodulation wave.

  The demodulation wave frequency conversion unit 2216 converts the demodulation wave in the demodulation intermediate frequency band, whose signal level has been amplified, into a demodulation wave in the baseband using the f11 signal. The demodulated wave frequency-converted by the demodulated wave frequency converter 2216 is input to the demodulator 2215 after an unnecessary wave generated by the frequency conversion is deleted by a bandpass filter (not shown).

  The demodulation unit 2215 demodulates the demodulated wave by the demodulation method of the same method as the modulation method set in the modulation unit of the corresponding subcarrier of the opposite wireless device, and outputs the reception signal aR of the user A in the baseband.

  The subcarrier unit b222 also includes a BPF 2228, a demodulation wave amplifier 2227, a demodulation wave frequency conversion unit 2226, and a demodulation unit 2225, which have the same configuration as described above. The demodulation wave frequency conversion unit 2226 uses the f12 signal, and the demodulation method of the demodulation unit 2225 is the same as the modulation method set in the modulation unit of the corresponding subcarrier of the opposite wireless device. The difference is that the reception signal bR of B is output.

  Further, in the configuration on the receiving side of the subcarrier unit a221 and the subcarrier unit b222, the function of increasing / decreasing the signal level of the subcarrier is not possessed, but an automatic level control function for keeping the signal level of the demodulator constant. have.

  The above is the configuration of the point-to-point wireless device according to the present embodiment.

[Single-carrier transmission and multi-carrier transmission]
Next, the difference between single-carrier transmission and multi-carrier transmission will be touched upon.

  FIG. 6 is a diagram illustrating a wireless transmission spectrum for explaining the difference between single carrier transmission and multicarrier transmission.

  6A illustrates the wireless transmission spectrum of the transmission signal (Txif) in the single carrier transmission mode, and FIG. 6B illustrates the wireless transmission spectrum of the transmission signal (Txif) in the multicarrier transmission mode.

  As shown in (a) of FIG. 6, the transmission signal (Txif) in the single carrier transmission mode includes a multiplexed signal (aT + bT) in which the transmission signal aT of the user A and the transmission signal bT of the user B are multiplexed. .. A point-to-point wireless device in the single carrier transmission mode has a configuration in which a transmission signal aT and a transmission signal bT are multiplexed in an interface section and a single carrier obtained by modulating the multiplexed signal is transmitted. Of course, at the time of reception, a single carrier is demodulated, and two multiplexed signals are separated and distributed to each user.

  Therefore, in the single-carrier transmission mode in which a plurality of signals are multiplexed, it is impossible to meet different demands of users for the channels to be used. For example, a user may desire that the transmission capacity of the wireless line used be large. On the contrary, some users may want to secure the transmission quality rather than the transmission capacity.

  On the other hand, in the multi-carrier transmission mode, as shown in FIG. 6B, the used radio frequency band is divided for each user, and user data is radio-transmitted as a subcarrier for each frequency band obtained by dividing this radio band. .. Therefore, in the multicarrier transmission mode, it is possible to construct a wireless line corresponding to different individual requests for each subcarrier forming the multicarrier.

  The point-to-point wireless device of the present embodiment individually sets a condition (parameter 1) that gives priority to a large transmission capacity of a wireless line and a condition (parameter 2) that gives priority to resistance to transmission quality deterioration due to fading, frequency interference, and the like. It has a configuration to realize.

  Further, when parameters are mixed, it is possible to set which parameter is prioritized for constructing subcarrier transmission. For a user whose parameter 1> 2 is a priority condition, subcarrier transmission with a setting that realizes wireless transmission capable of ensuring transmission capacity is constructed. On the contrary, for a user whose parameter 1 <2 is a priority condition, subcarrier transmission is set so as to realize wireless transmission in which the transmission quality can be secured by the transmission capacity.

[Setting of center frequency, bandwidth and modulation method of subcarrier]
In the following description, the spectrum mask that defines the allowable range of the wireless transmission spectrum of the carrier will be referred to as a wireless transmission spectrum definition or spectrum mask.

  In the ETSI EN302 217-2-2 standard, the same spectrum mask is used for the radio transmission spectrum of the single carrier transmission form shown in FIG. 6A and the radio transmission spectrum of the multicarrier transmission form shown in FIG. 6B. .. In other words, a signal obtained by combining single carriers for multicarrier transmission needs to satisfy the radio transmission spectrum regulation of single carrier transmission of the ETSI EN302 217-2-2 standard.

  The radio transmission spectrum shown in FIG. 6B is a transmission signal (Txif) during multi-carrier transmission in which two subcarriers respectively output by waveform shaping by the subcarrier unit a221 and the subcarrier unit b222 in FIG. 4 are combined. Is shown.

  In multi-carrier transmission, an interference guard frequency band is provided between subcarriers in the specified spectrum mask so that adjacent subcarriers that are combined do not overlap, and the center frequency and bandwidth of each subcarrier are set. There is a need.

  The center frequency and the bandwidth are set by the modulated wave frequency conversion unit 2212 and the frequency conversion circuit of the modulated wave frequency conversion unit 2222 and the band pass filter shown in FIG.

  That is, for the subcarrier of the signal aT shown in FIG. 6B, the center frequency is set by the f1 signal input to the frequency conversion circuit of the modulated wave frequency conversion unit 2212, and the bandwidth fa is set by the bandpass filter. Further, the subcarrier of the signal bT shown in FIG. 6B has the center frequency set by the f2 signal input to the frequency conversion circuit of the modulated wave frequency conversion unit 2222, and the bandwidth fb set by the bandpass filter.

  Then, the subcarriers whose increase / decrease control for adjusting the signal levels of the modulation wave amplifier 2213 and the modulation wave amplifier 2223 are completed are combined into multicarriers, and the IF band frequency conversion unit 2234 converts the transmission signals (Txif).

  Further, the modulation unit 2211 and the modulation unit 2221 are configured so that a modulation method according to a user's request can be appropriately selected and set, and the modulation method can be set according to the priority condition (parameter 1 / parameter 2) regarding the transmission environment requested by the user. The modulation method is selected and set.

  For users who give priority to securing the transmission capacity of the parameter 1, for example, 2048QAM, which has a large number of modulation levels and high transmission efficiency, is selected as the modulation method. That is, in the operation of setting the transmission capacity as a priority, a modulation method that can secure the maximum transmission capacity on a sunny day is set in the modulator instead of allowing a data error during rainfall.

  On the other hand, for a user who gives priority to securing the transmission quality of parameter 2, for example, 4PSK, which has resistance to transmission quality deterioration even when the propagation condition deteriorates, is selected as the modulation method and set in the modulation unit.

  Even in the receiving unit of the opposite wireless device, the demodulation method and the bandwidth are set in advance in accordance with the parameter 1 / parameter 2 of the priority condition regarding the transmission environment desired by the user in order to realize the wireless transmission desired by each user. I'll do it.

  The above center frequency, bandwidth, and modulation method settings are preset with the opposing wireless device before operation starts.

[Setting of center frequency and bandwidth of subcarrier according to parameters]
Next, the setting of the center frequency and the bandwidth of the subcarrier according to the above-mentioned parameter 1 / parameter 2 will be described.

In multi-carrier transmission, it is not possible to set the center frequency and bandwidth of each subcarrier by providing an interference guard frequency band between the subcarriers so that adjacent subcarriers do not overlap in the specified spectrum mask. As described above. This is because the provision of the interference guard frequency band prevents adjacent interference between subcarriers and ensures transmission quality in multicarrier transmission. The transmission quality, C / N (carrier Taizatsu sound ratio, Carrier-Noise ratio) is evaluated by.

  When allocating the respective subcarriers used by user A and user B within the same frequency band of the licensed radio frequency channel, the interference guard frequency band is normally located at the center of the frequency obtained by equally dividing the frequency band. It should be provided.

  However, when the priority conditions relating to the transmission environment of parameter 1 / parameter 2 required by the users are different, the modulation scheme applied between the users is different. As described above, for users who want to secure the transmission capacity with the parameter 1 as the priority condition, for example, 2048 QAM having high transmission efficiency is applied. Then, for a user who wants to prioritize ensuring transmission quality with parameter 2 as a priority condition, for example, 4PSK having resistance to deterioration in transmission quality is applied.

  As the modulation method becomes multi-valued, the interference guard frequency bandwidth necessary to secure the required C / N in the modulated wave modulated by the modulation method increases. On the contrary, since the required C / N in the modulated wave modulated by the multi-valued modulation method is small, the required interference guard frequency bandwidth can be small. Thus, when subcarriers modulated by different modulation schemes are mixed in the same radio transmission spectrum, it is necessary to secure an interference guard frequency band with a margin according to the modulation scheme.

  For example, if the setting of the interference guard frequency band is such that only the required C / N of a certain modulation method can be secured, a modulation method having a larger number of multivalues than that modulation method cannot be used. Therefore, in such a case, it is necessary to apply a modulation method with a multi-valued number smaller than that modulation method. This means that it is necessary to secure the interference guard frequency bandwidth so that the required C / N for the subcarriers by the high-level modulation method can be secured preferentially. In such a case, for example, an interference guard frequency band that can secure the C / N required in the 2048QAM modulation method using the maximum multilevel number may be set in advance.

  The center frequency and bandwidth of the subcarriers according to such parameters are assigned by the modulation wave frequency conversion unit 2212 of the subcarrier unit a221 and the modulation wave frequency conversion unit 2222 of the subcarrier unit b222.

  That is, the modulation method suitable for the request based on the operation contract between the user A and the user B is set in the modulation unit 2211 and the modulation unit 2221. Then, the interference guard frequency bandwidth that can secure the C / N required for each modulation method is obtained. The center frequency and the bandwidth are assigned in the modulated wave frequency conversion unit 2212 and the modulated wave frequency conversion unit 2222 so that the interference guard frequency band with more severe conditions can be set. The center frequency is set by the f1 signal and the f2 signal, and the bandwidth can be set by the characteristics of the bandpass filter. These are set at the time of initial setting based on the operating conditions of the wireless device.

  Further, even when the adaptive modulation method is used, it is necessary to set the interference guard frequency bandwidth based on the C / N securing requirement of each modulation method so that the modulation method that adaptively changes can be supported. .. For example, when adaptive modulation of 4PSK and 16/32/64/128/256/1024 / 2048QAM can be performed according to the state of the receiving side, the interference that can secure the C / N required in the maximum multilevel 2048QAM modulation scheme. The guard frequency band may be set in advance.

  Needless to say, when demodulating by the opposing wireless device, the f11 signal and the f12 signal are also set to frequencies in consideration of the interference guard frequency band as described above.

  The center frequency and the bandwidth are set in consideration of the interference guard frequency band required according to the above-mentioned modulation method, before the operation is started together with the opposing wireless device.

[Control of increasing / decreasing output level of modulated wave amplifier]
Next, the increase / decrease control of the signal level of the subcarrier by the modulated wave amplifiers 2213 and 2223, the detectors 2214 and 2224, the reference value storage unit 2231 and the level increase / decrease calculation unit 2232 illustrated in FIG. 4 will be described in detail.

  As described above, the level increase / decrease calculation unit 2232 calculates the signal increase / decrease level by verifying the difference between the information previously stored in the reference value storage unit 2231 and the signal level of each subcarrier input to the reference value storage unit 2231. To do. Then, the level increase / decrease calculation unit 2232 issues an increase / decrease instruction of the output level to the modulation wave amplifier 2213 or the modulation amplifier 2223. This increase / decrease control is repeated until the signal level of the combined subcarrier reaches an appropriate value within the range of allowable values defined in advance by a predetermined spectrum mask.

  The permissible value of the radio transmission spectrum of the point-to-point radio equipment is specified in the clause 4.2.4 of the ETSI EN302 217-2-2 standard.

  FIG. 7 is a diagram illustrating a transmission level deviation between subcarriers in a radio transmission spectrum according to the ETSI standard. The ETSI standard requires that the transmission level deviation between subcarriers forming a multicarrier be adjusted and controlled within a predetermined value k1 (dB).

  Output level increase / decrease control for a modulation wave amplifier is to control the signal level of the subcarrier output from the corresponding modulation wave amplifier so that the transmission level deviation between subcarriers becomes an appropriate value within the allowable value range. Is. In other words, it is the control that should be executed when the spectrum mask specified for single carrier transmission of the point-to-point wireless device is also applied to multicarrier transmission.

  The output level increase / decrease control for this modulation wave amplifier determines the reference subcarrier, which is the subcarrier to be used as the control reference, and the transmission level with respect to the signal levels of other subcarriers based on the signal level of the reference subcarrier. Control to adjust the deviation.

  It should be noted that this radio transmission spectrum regulation is a regulation in the radio frequency band (RF band). That is, in the RF signal radiated from the antenna, it is necessary to control so that the transmission signal level between the reference subcarrier and the other subcarriers is within a predetermined deviation.

  The point-to-point radio apparatus according to the present embodiment is characterized in that a multicarrier that defines a radio transmission spectrum that should be satisfied in the RF band is generated in the modulation intermediate frequency band. That is, the adjustment of the signal level between the subcarriers is executed by the increase / decrease control of the output level of the modulation wave amplifier of the multicarrier control unit 22.

  At this time, in the process of converting the signal in the intermediate frequency band generated by the multicarrier control unit 22 into the signal in the RF band by the wireless transceiver 23, a level error occurs with respect to the signal output by the multicarrier control unit 22. That is, the wireless transmitter / receiver 23 is provided at the subsequent stage of the multi-carrier control unit 22, and in the process of passing through the frequency conversion circuit and the amplifier circuit of the wireless frequency band, the deviation of each wireless transmitter / receiver, the deviation of the frequency band to be used, the environment An error occurs due to a deviation or the like. However, since the cause of this error is clear and is uniquely determined, the point-to-point wireless device of this embodiment stores this uniquely determined error in the reference value storage unit 2231 as a correction value in advance. Then, when increasing / decreasing the output levels of the modulated wave amplifiers 2213 and 2223 of the multicarrier control unit 22, the increasing / decreasing control is performed using the value converted by this correction value. Therefore, the signal levels of the subcarriers output from the modulated wave amplifiers 2213 and 2223 that have been subjected to the increase / decrease control by the correction value conversion are the specified radio transmission spectrum in the RF band radio signal converted by the radio transceiver 23. Within the transmission level deviation of.

  In other words, the point-to-point radio apparatus of this embodiment corrects the transmission level deviation obtained in the RF band by adjusting the signal level in the modulation intermediate frequency band using the correction value uniquely determined as described above. It has become.

[Control of increase / decrease in output level of modulated wave amplifier according to parameter priority condition]
As described above, the increase / decrease control of the output level of the modulated wave amplifier determines the reference subcarrier that is the subcarrier to be used as the control reference, and based on the signal level of the reference subcarrier, sets it to the signal level of other subcarriers. On the other hand, control is performed to adjust the transmission level deviation.

  The wireless device operates at the maximum wireless transmission level to ensure opposite reception quality. Therefore, normally, among the subcarriers forming the multicarrier, the subcarrier capable of the maximum radio output is set as the reference subcarrier. Then, the signal levels of other subcarriers are controlled so as to approach the reference subcarrier.

  On the other hand, on the other hand, it is specified by the above-mentioned priority condition regarding the transmission environment requested by the user to the wireless device, "priority to secure transmission capacity (parameter 1) / priority to secure transmission quality deterioration tolerance (parameter 2)". It is also possible to use the specified subcarrier as a reference.

  The criterion of the subcarrier designated by the user in the priority condition relating to the transmission environment requested by the wireless device is which of the parameter 1 and the parameter 2 is set to realize the wireless transmission.

  In the case of the condition (parameter 1) that prioritizes the securing of the transmission capacity under the condition that the interference does not occur, rather than the durability against the deterioration of the transmission quality, a high-multilevel modulation scheme with a large number of modulation levels (for example, , 2048 QAM) is set in the modulator of the wireless device. On the other hand, in the case of the condition (parameter 2) that gives priority to securing transmission quality deterioration tolerance, a low multilevel modulation scheme (for example, 4PSK) with a small number of modulation levels is set in the modulation unit of the wireless device. As described above, the reference modulation method is determined by the parameter 1 / parameter 2 corresponding to the user's request and is set in the modulator.

  In the ETSI standard, a value that should secure a required C / N between adjacent channels according to the modulation scheme is considered, and a spectrum mask having a different transmission level and range (side mask) is defined for each modulation scheme. For example, the spectrum mask of 4PSK is loosely defined, and the maximum transmission level is defined. On the other hand, as the value of 2048 QAM becomes higher and higher, the specification of the spectrum mask becomes stricter, the transmission level is low, and the side mask also becomes a stricter standard due to the higher and higher value.

  Therefore, when subcarriers under the condition of parameter 1 and subcarriers under the condition of parameter 2 coexist, a spectrum mask according to the parameter to be prioritized is applied, and the output level increase / decrease control of the modulated wave amplifier is controlled so as to satisfy the condition. There is a need to do. In other words, which one of the subcarriers under the condition of parameter 1 and the subcarrier under the condition of parameter 2 is set to realize the wireless transmission with priority.

  When priority is given to the transmission quality deterioration tolerance of parameter 2, a low-multilevel modulation method is selected. In this case, since a spectrum mask with a high transmission level is applied, increase / decrease control is performed based on a subcarrier with a high signal level (referred to as case 1).

  On the other hand, when priority is given to securing the data capacity of the parameter 1, the modulation method of high multi-valued is selected. In this case, since a spectrum mask having a low transmission level is applied, increase / decrease control is performed based on a subcarrier having a low signal level (referred to as case 2).

  Then, the signal level of the other subcarrier is increased or decreased with reference to the signal level of the reference subcarrier so that the radio transmission spectrum of the multicarrier satisfies the spectrum mask corresponding to the modulation method selected as the reference subcarrier. .. This can be realized by issuing a control instruction to increase / decrease the output level of the modulated wave amplifier of the subcarrier unit to be controlled.

[Explanation of increase / decrease control operation of output level of modulated wave amplifier]
The operation of increasing / decreasing the signal level of the modulated wave amplifier will be described with reference to FIGS. 8 and 9.

  FIG. 8 is a flowchart illustrating the overall operation of increasing / decreasing signal level control of subcarriers for multicarrier transmission. Further, FIG. 9 is a flow chart for explaining the operation of increasing / decreasing the output level of the modulated wave amplifier so as to satisfy the standard radio transmission spectrum regulation in the operation of FIG.

  The increase / decrease control of the output level of the modulated wave amplifier is an initial setting operation performed before the wireless device is put into operation in order to construct a wireless line that meets the priority condition desired by the user.

  As described above, according to the priority condition (transmission capacity priority: parameter 1 / transmission quality priority: parameter 2) related to the transmission environment desired by the user, the subcarrier modulation method, center frequency, and subcarrier generated by the corresponding subcarrier unit, The bandwidth is preset (S201).

  For example, a modulation method using an optimum modulation multi-value number according to a user's request is set in the modulation unit, and a center corresponding to an interference guard frequency band for securing C / N required for the modulation method of each subcarrier is set. The frequency and bandwidth are set in the modulated wave frequency converter.

  In addition, setting information regarding a priority condition such as which subcarrier signal level is used as a reference to control to satisfy the radio transmission spectrum regulation and setting information about an allowable range value of the transmission level to be increased / decreased are stored in the reference value storage unit 2231. It is held in advance (S202).

  In other words, information that sets whether the wireless device performs control with priority given to parameter 1 or control with parameter 2 and transmission level increase / decrease control in the wireless transmission spectrum regulation corresponding to the modulation method to be given priority. Holds the tolerance value of.

  The signal level of the subcarrier output from the modulated wave amplifier of each subcarrier unit is measured by the detector of the corresponding subcarrier unit and is notified to the reference value storage unit 2231 (S203).

  The reference value storage unit 2231, together with the information on the signal level of the subcarrier output by the corresponding modulated wave amplifier measured by the detector of each subcarrier unit, the level increase / decrease calculation unit 2232 together with the setting information held in advance in step S202. Output to.

  The level increase / decrease calculation unit 2232 performs the increase / decrease control of the output level for the subsequent modulated wave amplifiers based on the setting information regarding the priority condition desired by the user, which is previously stored in the reference value storage unit 2231. Therefore, the level increase / decrease calculation unit 2232 determines whether the parameter of the priority condition corresponding to the user request is the parameter 1 or the parameter 2 (S204).

  When the parameter 1 that prioritizes the transmission capacity is set (S204, parameter 1), it is necessary to operate in a modulation method with a large number of modulation levels and satisfy the radio transmission spectrum regulation corresponding to it. Therefore, in this case, the level increase / decrease calculation unit 2232 sets a subcarrier having a low signal level as a reference subcarrier in consideration of the radio output level value of the corresponding modulation method (case 2) (S205).

  Further, when the parameter 2 that prioritizes the transmission quality is set (S204, parameter 2), it is necessary to operate in a modulation method with a small number of modulation levels and satisfy the radio transmission spectrum regulation corresponding thereto. Therefore, in this case, the level increase / decrease calculation unit 2232 sets the subcarrier having a high signal level as the reference subcarrier in consideration of the radio output level value of the corresponding modulation method (case 1) (S206).

  The level increase / decrease calculation unit 2232 performs increase / decrease control of the output level of the modulation wave amplifier so that the signal level of the subcarrier output from the modulation wave amplifier satisfies the standard radio transmission spectrum regulation (S207).

  That is, the level increase / decrease calculation unit 2232 calculates whether or not the signal levels of the other reference subcarriers satisfy the allowable range to be set with reference to the set reference subcarrier signal level, and performs modulation based on the result. The output level of the wave amplifier is controlled to increase or decrease.

  For example, when the modulation method of the reference subcarrier is 4PSK of the multi-value modulation method, the corresponding radio transmission spectrum regulation also needs to comply with 4PSK, and the level increase / decrease calculation unit 2232 determines that the signal level of the subcarrier on the controlled side. Control to increase.

  On the other hand, when the reference subcarrier is the high-level modulation modulation method 2048QAM, the side mask according to the radio transmission spectrum regulation becomes strict. When the subcarrier on the controlled side is 4PSK modulated, the level increase / decrease calculation unit 2232 performs a decrease control to match the signal level to 2048QAM. In this case, it may be necessary to further reduce the signal level of the subcarrier on the controlled side in order to satisfy the regulation of the side mask.

  In this way, the level increase / decrease calculation unit 2232 performs increase / decrease control of the output level of the modulated wave amplifier based on the setting information regarding the priority condition of data transmission desired by the user.

  Next, the operation of step S207 of FIG. 8 will be described with reference to FIG.

  As described above, the increase / decrease control of the output level of the modulated wave amplifier is controlled so as to satisfy the radio transmission spectrum regulation corresponding to the modulation method of the reference subcarrier. Therefore, the level increase / decrease calculation unit 2232 controls the increase / decrease of the signal level of the subcarrier that is not the reference so that the standard radio output spectrum mask is satisfied.

  The level increase / decrease calculation unit 2232 acquires the signal level of each subcarrier output from the modulated wave amplifier (S211). This is measured by the detector of each subcarrier unit and notified to the reference value storage unit 2231 (step S203 in FIG. 8).

  Based on the information stored in the reference value storage unit 2231 and the measured signal level of each subcarrier, the level increase / decrease calculation unit 2232 satisfies the radio transmission spectrum prescribed range in which the signal level of each subcarrier is set. It is calculated whether or not there is (S212).

  When the specified allowable range is not satisfied (S212, No), the level increase / decrease calculation unit 2232 controls increase / decrease of the output level of the target modulated wave amplifier required to satisfy the radio transmission spectrum specification. The increase / decrease value of is calculated (S213).

  This is because the modulation wave on the control target side is set so that the difference between the signal level of the reference subcarrier and the signal level of the other subcarrier approaches the range of the allowable value that is specified in advance by the setting information of the reference value storage unit 2231. Calculate the increase / decrease value of the amplifier output level.

  The level increase / decrease calculation unit 2232 transmits the calculated increase / decrease value to the modulation wave amplifier on the control target side, and instructs the increase / decrease control of the output level in the modulation wave amplifier (S214).

  Upon receiving this increase / decrease control instruction, the signal level of the subcarrier output from the modulated wave amplifier whose output level has been increased / decreased is measured by the corresponding detector and is notified to the reference value storage unit 2231. As a result, the process returns to step S211 again.

  The processing from step S211 to step S214 is repeated until the determination result of step S212 becomes “Yes”. That is, when it is determined that the signal level of each subcarrier satisfies the range of the radio transmission spectrum regulation to be set, the increase / decrease control of the signal level for the modulated wave amplifier ends (S212, Yes).

  The signal level of each subcarrier, which is the final data based on the result of this increase / decrease control, is written in the nonvolatile memory of the reference value storage unit 2231.

  This is because when the wireless device is restarted for some reason, the data stored in this non-volatile memory is used to restart the device, thereby shortening the time for rebuilding the wireless line. Is.

  Further, when the control of increasing / decreasing the output level of the modulation wave amplifier is completed, the modulation wave output from each subcarrier section is combined by a combiner into a signal of a multicarrier transmission form. After being combined into a signal of a multi-carrier transmission form, it is converted into an IF band transmission signal by an IF band frequency conversion unit and sent to a wireless transceiver.

  The above-described increase / decrease control of the output level of the modulated wave amplifier is performed at the stage of initial setting of the device before the start of operation. Therefore, when the initial setting conditions such as the priority condition for multi-carrier transmission according to the user's request are changed after the operation is started, the control is started again by increasing / decreasing the output level of the modulated wave amplifier. When changing the initial setting condition, the interference wave guard frequency band may change due to the change of the applied modulation method. Therefore, as described above, the band is secured assuming the interference wave guard frequency band from 4PSK to 2048QAM, so that even if the priority condition is individually changed after the start of operation, it does not affect the users. You can also

  As described above, the point-to-point radio apparatus of the present embodiment generates and combines each subcarrier for multicarrier transmission in the modulation intermediate frequency band so as to satisfy the radio transmission spectrum regulation of single carrier transmission. ..

  Therefore, the radio transmission spectrum regulation for single carrier transmission is stored in the reference value storage unit 2231.

  Then, in the subcarrier unit that generates each subcarrier for multicarrier transmission, the center frequency and the bandwidth of the subcarrier are set to the interference guard frequency band so that each subcarrier can be arranged so as to satisfy the radio transmission spectrum regulation. Set in consideration. At this time, the modulation scheme applied to the subcarriers is considered.

  Further, the common control unit 223 increases / decreases the signal level between the generated subcarriers and controls the amplification of the subcarriers so that the transmission level deviation satisfies the radio transmission spectrum regulation. Further, in this amplification control, the amplification control is executed by using a correction value in consideration of a deviation when the radio transmission spectrum regulation adapted in the RF band is set in the modulation intermediate frequency band.

  The point-to-point wireless device of this embodiment also has a configuration for constructing a wireless line according to the priority condition desired by the user.

  A user request (parameter 1) that wants to prioritize transmission capacity and a user request (parameter 2) that wants to prioritize transmission quality can be individually set for each subcarrier to suit different user requests. For example, in response to a user's desire to prioritize transmission capacity, a subcarrier of a modulated wave to which a multilevel modulation method is applied is generated. Then, in response to a user's request to prioritize transmission quality, a subcarrier of a modulated wave to which a multilevel modulation method is applied is generated.

  Furthermore, when subcarriers under the condition of parameter 1 and subcarriers under the condition of parameter 2 coexist, a spectrum mask according to the parameter to be prioritized is applied, and increase / decrease control of the output level of the modulation wave amplifier is performed so as to satisfy it. It can be carried out.

  In order to construct a subcarrier transmission set to realize wireless transmission that gives priority to the condition of parameter 1, the signal level of each subcarrier is increased or decreased so as to comply with the wireless transmission spectrum regulation corresponding to the modulation method of high multilevel modulation. Control is performed to synthesize multi-carrier. This corresponds to case 2 described above, and the increase / decrease control is performed based on the subcarrier having a low signal level.

  On the other hand, in order to construct the subcarrier transmission set to realize the wireless transmission that gives priority to the condition of the parameter 2, the signal level of each subcarrier is adjusted so as to comply with the wireless transmission spectrum regulation corresponding to the modulation method of the multi-value modulation. And increase / decrease control is performed to combine into multiple carriers. This corresponds to case 1 described above, and the increase / decrease control is performed based on the subcarrier having a high signal level.

  As a result, for a user who gives priority to the condition of parameter 1, it is possible to provide wireless transmission capable of ensuring the maximum electric capacity in fine weather, as long as data errors during rain are allowed. On the contrary, for users who give priority to the condition of parameter 2, it is possible to provide wireless transmission in which deterioration of transmission quality and communication disconnection can be avoided even if fading or adjacent channel interference occurs on the propagation path.

(Modification 1)
In the second embodiment, the number of subcarriers for multicarrier transmission is two. However, the configuration is not limited to this, and a configuration may be used in which arbitrary plural subcarriers are generated and multicarrier transmission is performed.

  In this case, the multicarrier control unit 22 shown in FIGS. 3 to 5 may include subcarrier units corresponding to the number of subcarriers for multicarrier transmission. Then, on the transmission side, a plurality of subcarriers generated by each subcarrier unit may be combined by a combiner 2233 of the common control unit 223 into a signal of a multicarrier transmission form. Further, on the reception side, the demultiplexer 2235 of the common control unit 223 may distribute the signal in the multicarrier transmission form to each subcarrier.

  Further, the reference value storage unit 2231 of the common control unit 223 inputs the signal level of the subcarrier generated by each subcarrier unit, and the level increase / decrease calculation unit 2232 requires an increase / decrease instruction based on the result of the level increase / decrease calculation. It may be transmitted to the subcarrier section. If the number of subcarriers that make up a multicarrier is three or more, use one of the subcarriers as a reference to adjust the level higher than the reference by lowering the subcarriers that are originally lower than the reference. good.

  Furthermore, in each subcarrier unit, the center frequency, bandwidth, and interference guard frequency band of each subcarrier arranged in the radio transmission spectrum are determined according to the number of subcarriers to be multi-carrier transmitted and the modulation method. This is realized by appropriately setting the modulator and the modulated wave frequency converter.

  In particular, by configuring the device so that subcarriers can be additionally mounted in modules on a card-by-card basis, the number of subcarriers that make up a multicarrier can be easily added even after the device is operated, without adding equipment related to the RF band. can do.

(Modification 2)
The point-to-point radio apparatus of this embodiment is configured to perform multicarrier transmission so as to satisfy the radio transmission spectrum regulation for single carrier transmission. Therefore, it is possible to easily change the configuration of the wireless device operating in single carrier transmission to a wireless device operating in multicarrier transmission.

  For example, assume a case where a new user B is added to the same wireless line from a state in which single carrier transmission is performed only by the user A. At this time, when only the user A operates, single carrier transmission may be performed using one subcarrier unit and the common control unit. When the number of users B is newly increased and multicarrier transmission including the subcarriers of user B is performed, a subcarrier unit for user B may be added and multicarrier transmission may be performed as described above.

  Further, as another example, it is assumed that user A and user B multiplex their respective signals in the interface section and that the multiplexed signals are transmitted by single carrier. At this time, multi-carrier transmission becomes possible by bypassing the signal multiplexing function in the interface unit and changing the configuration to a radio device provided with a sub-carrier unit corresponding to each user and a common control unit.

  If configured as in the above modification, it is possible to provide a point-to-point wireless apparatus that can add the number of subcarriers and easily change the single subcarrier transmission form to the multicarrier transmission form. Therefore, it is possible to suppress the laying of a new wireless line, and it is possible to suppress the cost generation due to the equipment configuration.

  As described above, in the present embodiment, it is possible to provide a point-to-point radio apparatus and a communication control method capable of performing multicarrier transmission while satisfying the radio transmission spectrum regulation during single carrier transmission.

10, 20 Point-to-point radio equipment 11 Subcarrier generation means 12 Level increase / decrease calculation means 13 Multicarrier combination means 14 Radio transmission means 21 Interface section 22 Multicarrier control section 23 Radio transceiver 221 Subcarrier section a
222 subcarrier part b
223 Common control part 2211, 2221 Modulation part 2212, 2222 Modulation wave frequency conversion part 2213, 2223 Modulation wave amplifier 2214, 2224 Detector 2231 Reference value storage part 2232 Level increase / decrease calculation part 2233 Synthesizer 2234, 2236 IF band frequency conversion part 2215 , 2225 Demodulation section 2216, 2226 Demodulation wave frequency conversion section 2217, 2227 Demodulation wave amplifier 2218, 2228 BPF
2235 duplexer

Claims (7)

Depending on the number of subcarriers to be multi-carrier transmitted, generate sub-carriers converted into modulated waves in a modulation intermediate frequency band having a center frequency and a bandwidth that can be arranged so as to satisfy a predetermined radio transmission spectrum specification for single-carrier transmission, Subcarrier generation means corresponding to each subcarrier for multicarrier transmission,
The signal level of the subcarriers output by each of the subcarrier generation means, the subcarrier generation means of the modulated wave so as to satisfy the radio transmission spectrum regulation of the predetermined single carrier transmission that is held in advance. Level increase / decrease calculation means for instructing increase / decrease of signal level,
When the signal level of each of the sub-carriers satisfies the radio transmission spectrum regulation, multi-carrier synthesizing means for synthesizing into multi-carriers, frequency-converting to a radio intermediate frequency band, and outputting,
Radio transmitting means for converting the multi-carrier in the radio intermediate frequency band output by the multi-carrier synthesizing means into a transmission signal in the radio frequency band and outputting the transmission signal
Equipped with
The subcarrier generation means generates each subcarrier based on a modulation scheme selected and set so that guard bands having a frequency bandwidth set according to the modulation scheme are arranged between each other. Then
The frequency band width of the guard band, point to point wireless device that is set based on the carrier Taizatsu sound ratio corresponding to the modulation scheme. The bandwidth of the subcarrier is set based on the characteristics of the bandpass filter used when generating the modulated wave in the modulation intermediate frequency band.
The point-to-point wireless device according to claim 1 . A single carrier generating means for generating a single carrier by multiplexing a plurality of input signals with each other,
According to a setting change, bypassing the single carrier generating means, inputting the plurality of signals to the corresponding subcarrier generating means, respectively, bypass means for generating each of the subcarriers,
The wireless transmission means is capable of converting the single carrier into a transmission signal in the radio frequency band and outputting the signal.
The point-to-point wireless device according to claim 1 . The bypass unit, the subcarrier generation unit, the level increase / decrease calculation unit, and the multicarrier combination unit are respectively configured to be expandable to the single carrier generation unit and the wireless transmission unit.
The point-to-point wireless device according to claim 3 . It is possible to add more subcarrier generation means.
The point-to-point wireless device according to any one of claims 1 to 4 . Depending on the number of subcarriers to be multicarrier transmitted, generate subcarriers converted to modulated waves in a modulation intermediate frequency band having a center frequency and a bandwidth that can be arranged so as to satisfy the predetermined radio transmission spectrum specification of single carrier transmission,
The signal level of each of the subcarriers for multicarrier transmission is instructed to increase or decrease the signal level of the modulated wave so as to satisfy the radio transmission spectrum regulation of the predetermined single carrier transmission held in advance,
When the signal level of each of the subcarriers satisfies the radio transmission spectrum specification, the multicarrier is combined and frequency-converted into a radio intermediate frequency band, and output,
Converting and outputting the multicarrier of the wireless intermediate frequency band into a transmission signal of a wireless frequency band,
When generating the subcarriers, each of the subcarriers is arranged such that a guard band having a frequency bandwidth set according to the modulation scheme is arranged between the subcarriers based on the selected and set modulation scheme. Produces
Frequency band width of the guard band, a communication control method characterized in that it is set on the basis of the carrier Taizatsu sound ratio corresponding to the modulation scheme. On the computer,
Depending on the number of subcarriers to be multi-carrier transmitted, generate sub-carriers converted into modulated waves in a modulation intermediate frequency band having a center frequency and a bandwidth that can be arranged so as to satisfy a predetermined radio transmission spectrum specification for single-carrier transmission, Subcarrier generation processing corresponding to each subcarrier for multicarrier transmission,
An instruction to increase or decrease the signal level of the modulated wave so that the signal level of each of the subcarriers output by the subcarrier generation processing satisfies the radio transmission spectrum regulation of the predetermined single carrier transmission that is held in advance. Level increase / decrease calculation processing,
When the signal level of each of the subcarriers satisfies the radio transmission spectrum specification, a multicarrier combining process of combining into a multicarrier and performing frequency conversion into a radio intermediate frequency band for output,
A wireless transmission process of converting the multi-carrier of the radio intermediate frequency band output by the multi-carrier combining process into a transmission signal of a radio frequency band and outputting the converted signal ;
In the generation processing of the subcarriers, based on the modulation scheme selected and set respectively, the respective subcarriers are arranged so that the guard bands having the frequency bandwidth set according to the modulation scheme are arranged between each other. Generate,
A program in which the frequency bandwidth of the guard band is set based on a carrier-to-noise ratio according to the modulation method .

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