JP4019767B2 - Single frequency network system and repeater - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a repeater that amplifies and outputs an input signal, and more particularly, to a single frequency network system (SFN) suitable for use in a relatively small area such as in a home, and to this. It relates to repeaters.
[0002]
[Prior art]
There is a movement to construct a single frequency network using an Orthogonal Frequency Division Multiplexing (OFDM) modulation method, which is one of the multicarrier modulation methods that is considered suitable for broadband communication. OFDM has the advantage that the influence of delayed waves within a time corresponding to the guard interval length can be eliminated by adding a guard interval to each OFDM symbol in a multi-carrier transmission scheme.
[0003]
Utilizing this property, SFN repeaters have been actively researched and developed as antennas for digital terrestrial broadcasting. When the OFDM modulation system is used as a broadcast repeater, the received signal power is amplified and transmitted in order to increase the area that can be covered by the broadcast. Since a feedback path exists in space with respect to the receiving antenna, oscillation may occur unless the feedback gain is sufficiently reduced. Therefore, in order to lower the gain of the transmission / reception antenna, a single omnidirectional antenna is used as the transmission antenna, and an array antenna is configured with a plurality of omnidirectional antennas as the reception antenna. Various methods have been proposed in which the isolation pattern is adjusted so that nulls are directed in the direction of the transmitting antenna to achieve isolation between the transmitting and receiving antennas. Such techniques are disclosed in, for example, Japanese Patent Application Laid-Open Nos. 2001-136115 and 2001-223628.
[0004]
[Problems to be solved by the invention]
In the conventional method as described above, since it is assumed that SFN is applied to the form of broadcasting, it is sufficient to consider only the isolation between the transmission and reception antennas of one repeater. However, there is a problem when this SFN is applied to a home network.
[0005]
Advantages of applying SFN to a home (indoor) network are as follows. As a home network, since it is difficult to easily draw a wired network in a house, a scenario where it is built wirelessly is the most dominant. When building a home network wirelessly, a single cell network (one base station or one access point) is advantageous. This is because it is almost impossible to perform multi-cell operation by placing a plurality of base stations in a home like a public system. The reason why the multi-cell is not appropriate is that when a plurality of base stations are placed, wired wiring between the base stations becomes necessary, and a wired network must be laid in the house. Therefore, a wireless and single cell network seems promising in the home.
[0006]
Therefore, co-channel interference between adjacent houses becomes a problem. As a method for removing co-channel interference, there are a method using different frequencies and a method using time division access, and all of them deteriorate the frequency utilization efficiency. The essence of the problem is that since it must be a single cell, it must be transmitted with the appropriate power in order to be able to receive and receive radio waves from end to end. The range that gives is increased. Further, as shown in FIG. 1, the shape of the house is not a circle but a combination of rectangles. Therefore, when trying to communicate with a terminal in an arbitrary area in the house, the range that causes interference does not necessarily increase. Interference with a similar network in an adjacent house becomes a problem. In the example of FIG. 1, three houses 31, 32, and 33 are adjacent to each other, and each house has terminals 311, 312, 313; 321, 322; 331, 332, and 333 that form separate networks. For example, if attention is paid to the terminal 331 in the house 33, the cell range 35 includes the terminal 333 located farthest in the same house, but also includes the terminal 311 of the adjacent house 31 and the terminal 321 of the house 32 at the same time. ing.
[0007]
For example, when an adaptive array antenna is used to eliminate interference, there is a problem in cost because it is necessary to mount a plurality of antennas on each user terminal itself.
[0008]
As means for solving these problems, a method is conceivable in which signals are transmitted from each user terminal with low power, and relayed by a plurality of relays to a target user terminal. By using this method, there is an advantage that the interference area that influences the radio wave almost coincides with the shape of the house, and the useless interference area does not spread widely outside the house.
[0009]
As described above, when a plurality of repeaters are distributed in a house, radio waves having the same information fly from the plurality of repeaters. In other words, it is not a matter of considering only the isolation between the transmitting and receiving antennas of one repeater as discussed in the prior art. When there are the first repeater and the second repeater, the output of the first repeater and the output of the second repeater output the same information although there is a slight time lag. The first repeater needs to direct a directivity null so that it does not receive the transmission signal of the first repeater and also does not receive the transmission signal of the second repeater. At the same time, there are a large number of multipaths reflected by walls or the like in the house, and it is necessary to direct nulls in these directions. However, if the output signals of all the repeaters are not received, the system will not be lost. That is, in order to propagate information, it is necessary to receive only the output of a specific repeater and not receive the outputs of other repeaters. The method of specifying the repeater is also one of the problems.
[0010]
The present invention has been made in such a background, and an object thereof is to provide a communication system constituting a single frequency network suitable for use in a relatively small area.
[0011]
Another object of the present invention is to provide a repeater suitable for constructing such a communication system.
[0012]
[Means for Solving the Problems]
The single frequency network system according to the present invention has a single transmission antenna and a plurality of reception antennas, and the reception antenna includes a repeater capable of adaptive array processing and a single user terminal used by a user. In a single frequency network system, prior to data transmission from one user terminal to another user terminal, it is necessary to dynamically set the weight pattern of the adaptive array to be used by each repeater suitable for the communication. Features.
[0013]
By using a repeater capable of adaptive array processing in this way, a wireless-only network is provided. And before transmitting data from one user terminal to another user terminal, the adaptive array weight pattern to be used by each repeater suitable for the communication is dynamically set for each user terminal pair. As a result, the co-channel interference with the neighbor can be minimized.
[0014]
Specifically, before starting communication, each communication device of the repeater and the user terminal acquires information indicating the ease of communication with other communication devices. Next, each repeater notifies other communication devices of information on the ease of communication using a dedicated divided time slot. The central station selected from all the repeaters is used for each relay station so that the communication is performed correctly based on the communication request from the user terminal notified using the dedicated divided time slot. The adaptive array weight information to be notified is notified. Thus, after an appropriate weight is set to each repeater, communication between the user terminals is started.
[0015]
More specifically, at the time of initial setting, each of the communication devices transmits a known signal all at once, and a known signal for obtaining information on ease of communication when each communication device receives a known signal from another communication device. A signal transmission area and a plurality of information sharing areas following this area are provided. In each information sharing area, a dedicated time slot for transmitting information by each communication device is provided. Each repeater shares information on the ease of communication between communication devices.
[0016]
The central office preferably relays a repeater to be used in mutual communication between a plurality of user terminals based on information indicating ease of communication between the communication devices and other communication devices. Means for determining a route and holding weight information of the adaptive array of each repeater corresponding to the relay route.
[0017]
Based on the communication request from the user terminal, the central station transmits the weight information of the adaptive array of each repeater corresponding to the communication to the repeater, and the repeater that has received this transmission follows the weight information. Sets the weight of its own adaptive array.
[0018]
Preferably, the central station transmits the weight information of the adaptive array to be used by each repeater when transferring a transmission request from each user terminal to the central station and when reporting weight information from the central station to each repeater. A means for determining and transmitting to each repeater is further provided.
[0019]
Prior to a communication area for communication between user terminals, a communication request area for a user terminal that wants to transmit data to make a communication request to the central station, and a central station that has received this communication request are connected to each repeater. A weight setting area for notifying and setting weight information to be used by each repeater for transmission of the data is provided, and in the communication request area, at least each data terminal can issue a communication request. A divided time slot is provided, and in the weight setting area, a divided time slot dedicated to at least each repeater for notifying weight information corresponding to each repeater is provided, and each divided time slot in the communication request area and the weight setting area is provided. In order to enable communication between the corresponding communicator and the central office, A The weight of each repeater is switched for each divided time slot according to the weight information of the adaptive array.
[0020]
The repeater according to the present invention is a repeater used in a single frequency network system, and includes a plurality of receiving antennas, a plurality of receiving circuits corresponding to them, and weighted addition processing of outputs of the plurality of receiving circuits. A plurality of weight processing means for calculating and storing the weight information, a selection means for selecting one of the plurality of weight processing means, a transmission circuit for transmitting the output of the selected weight processing means, Communication between the user terminal and a transmission antenna connected to the transmission circuit, means for receiving and storing information on the ease of mutual communication between the communication devices of other repeaters and data terminals constituting the network Communication request area for user terminal that wants to transmit data to make a communication request to the repeater as the central office. In the weight setting area in which the central station that has received this communication request notifies and sets the weight information to be used by the repeater for the transmission of the data to other repeaters, Control means for sequentially switching selection of weight processing means according to predetermined weight information for each divided time slot provided exclusively.
[0021]
In this repeater, it is preferable that the first data table storing at least selection information of the weight processing means to be used by itself at the time of communication between any data terminals and the repeater selected as the central station. A second data table storing at least selection information of weight processing means to be used in the divided time slot assigned to each data terminal when the data terminal makes a communication request, and each relay at the time of communication between user terminals When the central office notifies each repeater of the selection information of the weight processing means to be used by the unit, the selection information of the weight processing means to be used by each repeater in the divided time slot corresponding to each repeater is stored. 3, and the control means performs a communication request from the certain data terminal prior to communication from the certain data terminal to the other data terminal. At the time of the divided time slot assigned to each data terminal, the selection information of the corresponding weight processing means specified in the second table is sequentially selected. When notifying the weight pattern to be used at the time of communication, the selection information of the corresponding weight processing means specified in the third table is sequentially selected at least at the divided time slot corresponding to each relay, At the time of communication to the data terminal, the selection information of the weight processing means corresponding to the transmission and reception data terminals is selected with reference to the first table.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0023]
FIG. 2A shows the configuration of the repeater used in the present invention. The repeater 10 includes a plurality of omnidirectional antenna elements 11a, 11b,... 11n as receiving antennas. Signals from the respective antennas pass through the receiving analog modules (RX_RF) 12a, 12b,... 12n, pass through the adaptive array antenna signal processing unit 14, and pass through the transmitting analog module (TX_RF) 16. The omnidirectional transmitting antenna 17 transmits to the space.
[0024]
FIG. 2B shows an example of the internal configuration of the adaptive array antenna signal processing unit 14. In this example, the adaptive array antenna signal processing unit 14 includes 31 weight processing units 140-1 to 140-31 having the same configuration and operating simultaneously. The outputs of these weight processing units are input to the weight coefficient pattern selection unit 149, and one output is selectively output to the transmission analog module 16. The weight coefficient pattern selection unit 149 is controlled based on the output of the repeater control table storage unit 148. The operations of each weight processing unit and repeater control table storage unit 148 are controlled by the control unit 147. Each weight processing unit includes a reception weight coefficient calculation and storage unit 143, a plurality of multipliers 141a to 141n that multiply the output of the reception analog modules 12a, 12b,. And an adder 142 for adding. The reception weighting factor calculation and storage unit 143 determines the weighting factor to be given to each multiplier based on the received signal and the known signal 145 at the time of initialization, which will be described later, and stores them in the data table 110 as shown in FIG. Remember as. The known signal is a signal unique to each repeater and terminal (generally referred to as a communication device), and is known data used for weight learning of the repeater. As such known data, for example, different random pattern data can be used. Thirty-one weight processing units 140-1 to 140-31 mean that up to 31 repeaters and terminals can be supported simultaneously.
[0025]
The repeater control table storage unit 148 stores, as a repeater control table, a weighting factor pattern (also simply referred to as a weight pattern) to be adopted by each repeater when communicating from one terminal to another terminal. It is a part to keep. As shown in FIG. 12, this table includes information (for example, pattern numbers # 1 to # 31) for specifying a weight pattern to be adopted by each repeater at the time of communication for each different combination of a transmitting terminal and a receiving terminal. The communication request area (time) when an arbitrary user terminal makes a communication request to the central station described later, as shown in the held data table 120 (first data table) and FIGS. Area) 51, a data table 130 (second data table) in which a weight pattern to be sequentially used by each repeater in each divided time slot is determined, and conversely between the next user terminal from the central office to each repeater A data pattern that determines the weight pattern that each repeater should use sequentially in each divided time slot of the weight setting area (time area) 52 when notifying the weight pattern that each repeater should take during communication. Data is a table 135 (third data table). These pattern numbers correspond to the respective weight patterns stored in the reception weight coefficient calculation and storage unit 143 of the 31 weight processing units 140-1 to 140-31 described above. These data tables 130 and 135 are shared by all the repeaters in this embodiment. Each repeater refers only to the data portion specified for itself.
[0026]
FIG. 3 shows the configuration of the user terminal 20 used in the present embodiment. The user terminal 20 has one antenna 21 and uses the antenna for both transmission and reception. The antenna 21 is connected to a transmission analog module TX_RF) 26 and a reception analog module (RX_RF) 25 via a switch (SW) 23, and these analog modules 25 and 26 are further connected to a modem unit (DMOD & MOD) 27. Connected with. The modem unit 27 is connected to a host control unit (not shown), and this control unit is further connected to a user interface unit such as an operation unit and a display unit. In the present embodiment, the configuration and operation of the user terminal 20 are the same as those in the prior art, and thus will not be described in detail.
[0027]
Hereinafter, a specific example of the operation of the present embodiment will be described.
[0028]
As an example, as shown in FIG. 7, repeaters A, B, C (10a, 10b, 10c) and terminals 20a, 20b as transmitters and receivers are arranged, and data from the terminal 20a is relayed. Consider a case in which relaying is performed in the order of A, B, and C, and finally transmitted to the terminal 20b. Here, for the sake of explanation, the terminal 20a considers only transmission and the terminal 20b considers only reception. The input adaptive array antenna of the repeater A adjusts the directivity of the antenna so as to receive only the output from the transmitter, and the array antenna so as to direct the null toward the output antenna of the repeaters A, B, and C. Learn the weights. The repeater B adjusts the antenna directivity so that only the output of the repeater A is received, and learns the antenna weight so that the null is directed toward the output antenna of the transmitter, the repeater B, and the repeater C. To do. The repeater C adjusts the antenna directivity so that only the output of the repeater B is received, and learns the antenna weight so that the null is directed toward the output antennas of the transmitter, the repeater A, and the repeater C. To do.
[0029]
The operation of this embodiment is roughly divided into an operation at the time of initial setting and an operation at the time of normal operation. In the example of FIG. 7, it has been described that the user specifies a relay route by the repeater, but actually, this route is automatically determined and determined by the system. Such automatic route determination processing is performed at the time of initial setting.
[0030]
Not all user terminals and repeaters can communicate directly. Therefore, prior to actual operation, the user terminal and the repeater need to recognize each other's existence and to recognize from which user terminal to which user terminal the communication to be performed. . This needs to be recognized by all repeaters in common. First, an initial operation for that purpose will be described. FIG. 9 is a flowchart showing an operation at the time of initial setting.
[0031]
Each user terminal and the repeater send out a beacon, and perform frame synchronization in an autonomous and distributed manner by listening to the beacon from each other (S11). This can be performed using a conventional method. A unique number (authorization code) is assigned in advance to the user terminal and the repeater. Here, a maximum of 32 units can be registered. 32 units is the total number of user terminals and repeaters. The unique number can be set manually by the user.
[0032]
Consider the case where there are a transmitter and a receiver, a repeater A, a repeater B, and a repeater C, as described above. Whether to relay in the order of repeaters A, B, C or B, C, A or C, A, B in practice depends on the position of the repeater and the position of the transmitter and receiver. Dependent. Prior to the transmission and reception of data, this positional relationship is automatically grasped and a relay route is determined. The method for this is as follows.
[0033]
First, an array antenna is learned by a known signal in each repeater (S12). Each repeater has a desired signal power versus an interference signal power SIR when any one of the output signals from the transmitter or a repeater other than itself is a desired signal and the other output signal is an interference signal power. (Signal Interference Ratio) or desired signal power to interference noise signal power SINR (Signal Interference Noise Ratio) is calculated. For example, the repeater A calculates a weight so as to receive a known signal from the repeater B, calculates SIR (B) when received using the weight, and further, knows the known signal from the repeater C. The weight is calculated so as to be received, the SIR (C) is calculated using the weight, and the weight is calculated so as to receive the known signal from the transmitter, and the received weight is used. If so, the SIR (TX) is calculated. In this way, three types of SIR are calculated in total. In a network where there are other repeaters and transmitters, the SIR is calculated for each of them. Similarly, the same calculation is performed for the repeaters B and C.
[0034]
More specifically, prior to the actual transmission of data, each repeater and each terminal constituting the network transmit the unique known signal as described above at a constant period from the transmission antenna. In the present embodiment, as shown in FIG. 4, for example, an initial setting frame is provided at a rate of once every plural times in a communication frame having a frame interval of 2 ms. An initial setting operation is executed in this initial setting frame. The appropriate value of “multiple times” may vary depending on the application and situation, but is 1000 times in this embodiment. The initial setting frame includes a known signal transmission area 411 and a plurality of information sharing areas 1 to N (412a to 412N) following the known signal transmission area 411.
[0035]
Within the known signal transmission area 411, each repeater and terminal generates a known signal, and each repeater responds to its authorization code from other repeaters and terminals by means of an adaptive array antenna on its receiving side. Receive a known signal. At this time, each repeater learns a weighting factor for each repeater and each terminal other than itself so as to form a directivity that receives only the output of that terminal or repeater. For this purpose, for example, an RLS (Recursive Least Square) algorithm or the like is used with MMSE (Minimum Mean Square Error) as an evaluation criterion. When the above SIR calculation is performed, it is possible to mutually obtain SIRs that are values of ease of communication between the respective repeaters and the transceivers.
[0036]
Next, the SIR of the communication device corresponding to each unique number is made known to each communication device. Even if each communicator can communicate with only a part of the communicators, by repeating this information transmission by complete time division for a plurality of cycles (N times in FIG. 4, for example, 20 times, etc.) Can be shared (S13, S14).
[0037]
In this embodiment, in order to share this SIR information with each other, communication is performed using a special channel. The special channel is a predetermined area (information sharing area) in a frame (initial setting frame) provided for transmitting the SIR information once in a plurality of frames. Information is transmitted while avoiding interference by time division multiplexing in which time (time slot) is uniquely assigned to the transceiver. Since this information is transmitted with low power, it can reach only a nearby repeater or transceiver. The repeater or the transmitter / receiver receiving the signal adds the SIR information held by itself in the time slot allocated for itself and transmits the information. In each of the plurality of information sharing areas 412a to 412N following the known signal transmission area 411 in FIG. 4, a complete time-division in which a unique time slot is assigned to each communication device (user terminal and repeater). An area (information sharing area). In this example, time slots from the communication device 0 to the communication device 31 are provided, and in each time slot, only the communication device transmits information to other communication devices. Of course, there may be a communication device that can correctly receive this information and a communication device that does not. However, a communication device that has successfully received information can be shared by all the repeaters by repeating N times the operation of adding its own retained information to the received information and sequentially transmitting it.
[0038]
An example of such shared information is shown in FIG. FIG. 6 is a data table 60 of SIR between communication devices acquired by the initial setting. This table describes SIR (dB value) indicating the ease of communication from the communication device on the transmission side to the communication device on the reception side. The numbers shown in parentheses below each dB value indicate the number of the weight pattern used when the SIR value is obtained at each receiving side repeater. The SIR information is information collected individually in each repeater, but is supplied to all repeaters in the information sharing area. However, in principle, it is sufficient if the “central office” holds this table. In the example of the figure, the case of three repeaters and two user terminals is shown. The vertical axis represents the communication device on the reception side, and the horizontal axis represents the communication device on the transmission side.
[0039]
Next, one repeater is selected as the central station (S15). This central office controls communication. As a method of selecting the central station, one relay station may be fixedly determined in advance, or may be automatically determined based on table data as shown in FIG. As the latter method, the relay station that has been declared to be the central station first becomes the central station, or the relay station that requires the least number of relays to contact other communication devices becomes the relay station. Processing for automatically determining the central office can also be performed in the information sharing area.
[0040]
Since the central office can determine in advance an optimum route for transmitting information to all the communication devices, it is possible to transmit data to each communication device. Conversely, the optimum route from each communication device to the central office is also determined. The weight pattern data for these optimum routes is transmitted to each repeater as tables 130 and 135 (FIG. 13) (S16). Further, a relay route is determined for communication between each user terminal, and a weight pattern table 120 for each repeater is created and stored (S17). In each relay path, each repeater basically determines the relay path so as to receive only the output from one place, and therefore no closed loop exists, so oscillation due to feedback does not occur.
[0041]
If the example of FIG. 7 is considered again, the repeater A receives only the output signal of the user terminal 1, and uses the weight learned so that the output signals of the repeaters A, B, and C are not received as interference. The repeater B uses a weight learned so as to receive only the output from the repeater A. Similarly, the repeater C uses a weight learned so as to receive only the output of the repeater B.
[0042]
Note that, when passing through the three repeaters A, B, and C, possible routes are A-B-C, A-C-B, B-A-C, B-C-A, and C-A-B. , C-B-A, there are six candidates, but the central office determines which can transmit through the higher SIR. That is, the smallest SIR among a plurality of SIRs in one route is compared in each route, and the route having the largest value is selected as the target route. Since there are at most several tens of repeaters in one house, this determination can determine the optimum relay route by brute force calculation.
[0043]
Next, the normal operation will be described with reference to the flowchart of FIG. This process is executed in the communication request area 51, the weight setting area 52, and the communication area 53 between the user terminals following this. These areas can correspond to normal frames other than the initial setting frame of FIG.
[0044]
The terminal that wishes to transmit data notifies the central station of the terminal number of the other party (S21). This notification is performed in a time slot assigned to itself in the communication request area 51 (FIG. 5). That is, in each time slot, each repeater dynamically changes the weighting factor so as to select the weight pattern defined for the partner to be received by the relay station corresponding to the time slot according to the table 130 (FIG. 13). I will do it. Thereby, in each time slot in the communication request area 51, the communication path from each terminal to the central office is dynamically switched and set. The number of time slots in the communication request area 51 is sufficient as long as the number of user terminals, but in the example shown in the figure, 32 are provided so as to be compatible with all communication devices.
[0045]
In the subsequent weight setting area 52, the weight pattern of each repeater is switched in each time slot for notification based on the table 135 (FIG. 13). Thereby, in each time slot, the communication path from the central office to each repeater is dynamically switched and set. In this case as well, in practice, only the time slot assigned to the repeater needs to function. In these functioning time slots, the corresponding weight pattern in the table 120 is notified to each repeater based on the unique numbers of the transmitting terminal and the receiving terminal (S22).
[0046]
In the communication area 53 between user terminals, each repeater selects the weight pattern notified in the weight setting area 52. As a result, a relay path from the requested transmission terminal to the reception terminal is established, and communication between the terminals can be performed (S23).
[0047]
When communication in the reverse direction is required, a transmission request is newly transmitted from the terminal on the transmission side to the central station, and the same processing as described above is performed to establish a relay path and perform communication.
[0048]
FIG. 8 shows an example of a relay route in a house. In one house (for example, the house 33), an arbitrary transmitter 20a and receiver 20b can communicate with each other via the repeaters 10a to 10d without receiving interference between adjacent houses (for example, the house 32). It becomes possible. The example of FIG. 8 shows an example in which four repeaters are used.
[0049]
By using the repeater in this way, it becomes possible to provide a service that enables wireless communication to every corner with minimum power in the house.
[0050]
The preferred embodiment of the present invention has been described above, but various modifications and changes can be made. For example, the repeater weight pattern table 120 for each bidirectional communication between terminals shown in FIG. 12 is held only in the central office, and the repeater is notified of the weight pattern. The same table may be held in each repeater and the central station may instruct the repeater to identify the transmitting terminal and receiving terminal identification information.
[0051]
The repeater is provided with a plurality of weight processing units and operated in parallel at the same time. However, when the calculation of the weighting factor and the switching setting can be performed at a very high speed, a single weight processing unit may be used. .
[0052]
【The invention's effect】
According to the present invention, it is possible to provide a wireless-only network by using a repeater even if there is only a short-distance wireless communication means in a network within a relatively small area. In addition, since a communication method that minimizes co-channel interference between adjacent areas can be provided, it is possible to improve frequency utilization efficiency.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining problems of a conventional single frequency network.
FIG. 2 is a block diagram showing a schematic configuration (a) and a detailed configuration (b) of a repeater in an embodiment of the present invention.
FIG. 3 is a block diagram showing a schematic configuration of a user terminal used in the embodiment of the present invention.
FIG. 4 is an explanatory diagram of a communication frame used in the embodiment of the present invention.
FIG. 5 is an explanatory diagram of a normal frame in the communication frame of FIG. 4;
FIG. 6 is a diagram showing a data table of SIR between communication devices acquired by the initial setting according to the embodiment of the present invention.
FIG. 7 is a diagram illustrating a state of communication between user terminals via a plurality of repeaters.
FIG. 8 is a diagram showing an example of a relay route in a house according to the embodiment of the present invention.
FIG. 9 is a flowchart showing an operation at the time of initial setting according to the embodiment of the present invention.
FIG. 10 is a flowchart showing the normal operation in the embodiment of the present invention.
FIG. 11 is a diagram showing a data table stored in a reception weight coefficient calculation and storage unit in the embodiment of the present invention.
FIG. 12 is a diagram showing a data table holding information for specifying a weighting factor pattern to be adopted by each repeater at the time of communication for each different combination of a transmitting terminal and a receiving terminal in the embodiment of the present invention. .
FIG. 13 shows in advance a weighting factor pattern to be taken by each repeater when communicating from the central station to each repeater other than the central station and conversely from each repeater other than the central station to the central station in the embodiment of the present invention. It is a figure which shows the defined table.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Repeater, 10a-10d ... Repeater, 11a-11n ... Omnidirectional receiving antenna, 12a-12n ... Receiving analog module, 14 ... Adaptive array antenna signal processing part, 16 ... Analog module for transmission, 17 ... None Directional transmitting antenna, 14 ... adaptive array antenna signal processing unit, 20 ... user terminal, 20a ... user terminal, 20b ... user terminal, 60 ... data table, 110 ... data table, 120 ... data table, 130 ... data table, 135 ... Data table, 140-1 to 140-31 ... Processing unit, 141a to 141n ... Multiplier, 142 ... Adder, 143 ... Storage unit, 145 ... Known signal, 149 ... Coefficient pattern selection unit, 147 ... Control unit, 148 ... repeater control table storage unit, 411 ... known signal transmission area, 412a 412N ... information sharing area

Claims (10)

In a single frequency network system having a transmission antenna and a plurality of reception antennas, a repeater capable of adaptive array processing at the reception antenna, and a plurality of user terminals used by the user,
Before starting communication, means for acquiring information representing the ease of communication between the communication devices of the repeater and the user terminal with other communication devices;
Means for each repeater to notify other communication devices of information on the ease of communication using a dedicated divided time slot;
The central station selected from all the repeaters is used for each relay station so that the communication is correctly performed based on the communication request from the user terminal notified using the dedicated divided time slot. A single frequency network system characterized by notifying weight information of an adaptive array to be transmitted. At the time of initial setting, each of the communication devices transmits a known signal all at once, and each communication device receives a known signal from another communication device, and a known signal transmission area for obtaining information on ease of communication, and this A plurality of information sharing areas following the area are provided, and in each information sharing area, a dedicated divided time slot is provided for each communication device to transmit information. 2. The single frequency network system according to claim 1, wherein each repeater shares information on ease of communication. The central station is a repeater determined from all repeaters or a repeater determined based on information on ease of communication between the communication devices. Single frequency network system. The central station determines a relay route of a repeater to be used in mutual communication between a plurality of user terminals based on information indicating ease of communication between each communication device and another communication device. 4. The single frequency network system according to claim 1, further comprising means for holding weight information of an adaptive array of each repeater corresponding to the relay path. Based on the communication request from the user terminal, the central station transmits the weight information of the adaptive array of each repeater corresponding to the communication to the repeater, and the repeater that has received this transmission follows the weight information. 2. The single frequency network system according to claim 1, wherein the weight of the adaptive array is set. The central station determines in advance the weight information of the adaptive array to be used by each repeater at the time of transmission of a transmission request from each user terminal to the central station and at the time of notification of weight information from the central station to each repeater. 2. The single frequency network system according to claim 1, further comprising means for transmitting to each repeater. Prior to a communication area for communication between user terminals, a communication request area for a user terminal that wants to transmit data to make a communication request to the central station, and a central station that has received this communication request are connected to each repeater. A weight setting area for notifying and setting weight information to be used by each repeater for transmission of the data is provided, and in the communication request area, at least each data terminal can issue a communication request. A divided time slot is provided, and in the weight setting area, a divided time slot dedicated to at least each repeater for notifying weight information corresponding to each repeater is provided, and each divided time slot in the communication request area and the weight setting area is provided. In each divided time slot according to the weight information of the adaptive array so that communication between the corresponding communication device and the central office can be performed. Single frequency network system according to claim 2, wherein the weight of the repeater is switched. A repeater used in a single frequency network system,
A plurality of receiving antennas and a plurality of receiving circuits corresponding thereto;
A plurality of weight processing means for performing weighted addition processing of outputs of the plurality of receiving circuits and calculating and storing the weight information;
Selecting means for selecting one of the plurality of weight processing means;
A transmission circuit for transmitting the output of the selected weight processing means;
A transmission antenna connected to the transmission circuit;
Means for receiving and storing information on the ease of mutual communication between other repeaters and data terminal communicators constituting the network;
Prior to the communication area for communication between user terminals, the user terminal that wants to transmit data receives a communication request area for making a communication request to a repeater as a central station, and accepts this communication request. In the weight setting area in which the central station notifies and sets the weight information to be used by the repeater for transmission of the data to other repeaters, the division time provided exclusively for each communication device A repeater comprising a control means for sequentially switching selection of weight processing means for each slot in accordance with predetermined weight information. A first data table storing selection information of weight processing means to be used at least by itself during communication between arbitrary data terminals;
A second information storing at least selection information of weight processing means to be used in a divided time slot assigned to each data terminal when an arbitrary data terminal makes a communication request to the repeater selected as the central station. Data table,
Weight processing means to be used by each repeater in a divided time slot corresponding to each repeater when the central office notifies each repeater of selection information of weight processing means to be used by each repeater during communication between user terminals A third data table storing selection information of
When the control means makes a communication request from a certain data terminal prior to communication from a certain data terminal to the other data terminal, it is designated in the second table at least at the divided time slot assigned to each data terminal. When the central station notifies each repeater of the weight pattern to be used during communication between the data terminals, the division time corresponding to at least each repeater is sequentially selected. The selection information of the corresponding weight processing means specified in the third table at the time of slot is sequentially selected, and the transmission and reception are performed with reference to the first table during communication from the certain data terminal to another data terminal. 9. The repeater according to claim 8, wherein selection information of weight processing means corresponding to the data terminal is selected. The control means at the time of initial setting,
In addition to transmitting its own known signal, it seeks information on ease of communication when receiving a known signal from another communication device,
Next, information on the ease of communication is transmitted to the other repeater in the dedicated divided time slot assigned to itself, and from the other communication device in the dedicated divided time slot assigned to the other communication device. 10. The information on the ease of communication between all the communication devices is collected by receiving the information on the ease of communication and repeating this transmission and reception. Repeater.

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