JP4199775B2 - GSM pseudo base station equipment - Google Patents

Description

  The present invention relates to a GSM pseudo base station apparatus for conducting a test of a mobile terminal to which the GSM standard is applied.

  There is a GSM (Global System for Mobile communication) standard as a mobile communication standard in practical use in Europe and the United States. FIG. 6 is a diagram showing the relationship between the base station 1 and the GSM terminal 2. A downlink signal 3 (down link) is transmitted from the base station 1 to each GSM terminal 2, and an uplink signal 4 (up link) is transmitted from each GSM terminal 2 to the base station 1.

FIG. 7 is a format diagram of the GSM downlink signal 3 transmitted from the base station 1 to each GSM terminal 2. The control channel (Control Channel) 5 frequency (carrier frequency) f ₁ in the GSM downlink signal 3 includes two channels of the frequency (carrier frequency) f ₂ of the communication channel (Traffic Channel) 6. Eight slots from 0th to 7th are formed in one frame of each of the channels 5 and 6.

In the control channel 5, 1 and the zeroth slot only control data 7 of the signal level L ₁ in the beginning of the frame is incorporated, the remaining in the first to seventh seven slots, the signal level of the control data 7 L ₁ equal to the signal level L ₁ of the dummy burst (dummy burst) 8 is incorporated. This dummy burst 8 is combination data of “0” and “1” defined in advance by the standard (3GPP TS 45.002: GSM / EDGE third generation technical specification study group) (see non-patent literature). .

In the communication channel 6, communication data 9 having a signal level L ₂ indicating transmission contents is incorporated in a plurality of slots after the second slot. Nothing is incorporated in the slot in which the communication data 9 in the communication channel 6 is not incorporated.

Accordingly, in the base station 1, two high-performance oscillators, that is, an oscillator having a frequency f ₁ for the control channel 5 and an oscillator having a frequency f ₂ for the communication channel 6 are provided.

  On the other hand, in the GSM terminal 2 that receives the downlink signal 3 as described above, the reception level of the control channel 5 is monitored, and when a signal level equal to or higher than a predetermined lower limit level is detected, The control data 7 and the communication data 9 are received by determining that they exist within one reception area. When the reception level of the control channel 5 is less than the lower limit level, the own GSM terminal 2 judges that it is out of the reception area of the base station 1 and disconnects the line formed with the base station 1.

In this case, the SGM terminal 2 does not necessarily receive the dummy burst 8 of the control channel 5 during communication. Therefore, in order to reduce the manufacturing cost, the reception frequency is switched by one receiving circuit. In general, the downstream signal 3 is received. That is, in the 0th slot at the beginning of one frame, the control data 7 is received with the reception frequency f ₁ , the reception level is determined, and the control data 7 is read. Next, the reception frequency is switched to f ₂ in the first slot, and each communication data 9 is received in the second to fifth slots.

  Further, as a device for testing various characteristics including the transmission / reception function of the GSM terminal 2, there is a GSM pseudo base station device 10 shown in FIG. The GSM pseudo base station apparatus 10 transmits a downlink test signal 3a substantially the same as the downlink signal 3 from the base station 1 to the GSM terminal 2 to be tested, and the correct uplink signal 4a is transmitted from the GSM terminal 2 to be tested. Make sure. Note that the GSM pseudo base station apparatus 10 and the GSM terminal 2 are connected by wire.

In such a GSM pseudo base station apparatus 10, in order to reduce manufacturing costs, as shown in FIG. 9, it is common to create a downlink test signal 3 a by switching the oscillation frequency with one oscillator. is there. That is, 1 in the zeroth slot beginning of the frame, the oscillation frequency transmits control data 7 of the control channel 5a in the f _1, the oscillation frequency in the first slot is switched to f _2, the second to fifth slots To transmit the communication data 9 of the communication channel 6a. Therefore, the dummy burst 8 included in the regular control channel 5 shown in FIG. 7 is not transmitted to the control channel 5a.
3GPP TS 45.002 V6.12.0 (2005-11): 3rd Generation Partnership Project; Technical Specification Group GSM / EDGE Radio Access Network Multiplexing and multiple access on the radio path (Release 6)

  However, such a GSM pseudo base station apparatus 10 still has the following problems to be improved.

That is, in recent years, GSM terminals 2 having high functions such as e-mail, data transmission, packet communication as well as voice calls using mobile communication have been put into practical use. In the GSM terminal 2 having such a function, the signal level monitoring timing of the control channel 5a of the GSM terminal 2 includes not only the 0th slot of the control channel 5 but also the middle portion of the first slot. It was. This is because the switching frequency of the reception frequency in the reception circuit of the GSM terminal 2 is increased, and the reception frequency is switched from the frequency f ₁ to the frequency f ₂ immediately before the start of the second slot, or two reception circuits are connected to the GSM terminal 2. This is considered to be due to the fact that is incorporated.

  In this case, since the GSM terminal 2 to be tested does not have the dummy burst 8 in the first slot in the downlink test signal 3a output from the GSM pseudo base station apparatus 10, the control channel is controlled during this first slot period. When the signal level 5a is detected, the reception level becomes less than the lower limit level, and the GSM terminal 2 of the own terminal determines that it is outside the reception area of the base station 1 and disconnects the line. That is, there is a concern that a correct test cannot be performed on the GSM terminal 2.

  The present invention has been made in view of such circumstances, and has a simple configuration, can incorporate a dummy burst into a downlink test signal, has an inexpensive circuit configuration, and has a high-functionality with a packet communication function. It is an object of the present invention to provide a GSM pseudo base station apparatus that can correctly test a GSM terminal.

  In order to solve the above problems, the present invention sends a downlink test signal composed of a control channel including control data and a communication channel including communication data to a GSM terminal to be tested, and tests the GSM terminal. In the GSM pseudo base station apparatus to perform, a data creation unit that creates control data and communication data, and synthesizes and outputs the created control data and communication data according to time slots, and from this data creation unit The respective frequencies of the output time-division synthesized control data and communication data are respectively set to the first frequency and the second frequency supplied by switching the oscillation frequency from one first oscillator. A transmission unit that outputs the transmission signal as a transmission signal, a dummy signal generation unit that generates a dummy signal having the first frequency from the second oscillator, and the dummy signal generation unit. GSM to be tested as a down test signal by adding the dummy signal control unit for determining the output level of the dummy signal generated by the unit, the transmission signal output from the transmission unit and the dummy signal output from the dummy signal generation unit And an adder for sending to the terminal.

  Another invention is a GSM pseudo base station that sends a downlink test signal comprising a control channel including control data and a communication channel including communication data to a GSM terminal to be tested, and tests the GSM terminal. In the apparatus, a data creation unit that creates control data and communication data, and synthesizes and outputs the created control data and communication data according to time slots, and a time division output from the data creation unit Each frequency of the synthesized control data and communication data is set to a first frequency and a second frequency supplied by switching the oscillation frequency from one first oscillator and output as a transmission signal. Transmitting unit, a dummy signal generating unit for generating a dummy signal having the first frequency from the second oscillator, and a dummy signal generated by the dummy signal generating unit -Dummy signal control unit that determines the output level of the signal and the duration of the output level; the transmission signal output from the transmission unit and the dummy signal output from the dummy signal creation unit are added to obtain the test target as a downlink test signal And an adder for sending to the GSM terminal.

  In the GSM pseudo base station apparatus configured as described above, control data and communication data are created, and these are time-division combined according to time slots. Then, in the transmitter, like the conventional GSM pseudo base station apparatus, the oscillation frequency is switched to the first and second frequencies with one oscillator, and each frequency (carrier frequency) of the control data and communication data is changed to the first frequency. 1 and 2 are set to the second frequency to obtain a transmission signal. This transmission signal does not include a dummy signal.

  Therefore, the dummy signal included in the control channel of the downlink signal output from the legitimate base station is created by the dummy signal creating unit that creates only the dummy signal, and the created dummy signal is added to the transmission signal by the adding unit. By doing so, a downlink test signal including control data, a dummy signal, and communication data is obtained.

  In this case, the purpose of using the dummy signal is only used to determine whether or not the control channel of the received downlink signal satisfies the preset lower limit signal level in the GSM terminal. High levels of accuracy, waveform quality, etc. are not required.

  Therefore, the second oscillator for creating the dummy signal having the first frequency can be configured at a low price. Therefore, the test function for the GSM terminal can be improved without significantly increasing the manufacturing cost of the GSM pseudo base station apparatus while maintaining a high test function for the GSM terminal.

  According to another invention, in the GSM pseudo base station apparatus according to the invention described above, the dummy signal control unit constantly outputs a dummy signal having a predetermined signal level.

  In the GSM pseudo base station apparatus configured as described above, the dummy signal is always output at a specified signal level lower than the signal level of the control channel determined in advance by the standard. Therefore, the GSM terminal can detect the signal level of the dummy signal included in the downlink test signal.

  According to another aspect of the present invention, in the GSM pseudo base station apparatus according to the above-described invention, the dummy signal control unit exceeds the output level of the dummy signal above the specified signal level during a period when the control data of the control channel is not transmitted. Set to value. In this case, the GSM terminal only needs to detect the signal level of the dummy signal included in the downlink test signal during the period when the control data is not transmitted.

  In another invention, in the GSM pseudo base station apparatus according to the invention described above, the dummy signal control unit is configured to output the dummy signal in any time slot designated in a plurality of time slots constituting one frame of the control channel. The output pattern is set.

  In such a GSM pseudo base station apparatus, the pattern of the output level for one frame in the dummy signal can be set arbitrarily, so that the GSM pseudo base station apparatus detects the execution timing of the level detection of the dummy signal of the GSM terminal. Various tests such as reception sensitivity detection in each time slot in one frame can be performed.

  According to another invention, in the GSM pseudo base station apparatus of the above-described invention, the dummy signal creation unit is a combination data of “0” and “1” predetermined in the above-mentioned standard (3GPP TS 45.002). Create a dummy signal based on the code.

  According to the present invention, a GSM terminal can be correctly tested even with a high-performance GSM terminal having a packet communication function with an inexpensive circuit configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic diagram showing a connection state between a GSM pseudo base station apparatus according to a first embodiment of the present invention and a GSM terminal to be tested.

  The GSM pseudo base station apparatus 10a according to the first embodiment transmits a downlink test signal 3b to the GSM terminal 2 to be tested, and confirms that the correct uplink signal 4b is transmitted from the GSM terminal 2. The GSM pseudo base station apparatus 10a and the GSM terminal 2 are connected by wire. More specifically, the GSM pseudo base station apparatus 10a controls the GSM terminal 2 to be tested to be in a loopback state, sends a downlink test signal 3b, and returns from the GSM terminal 2 via the uplink signal 4b. Based on the data, tests such as “connection test”, “transmission power measurement”, “modulation analysis measurement”, and “reception sensitivity measurement” of the GSM terminal 2 to be tested are performed.

  FIG. 2 is a block configuration diagram showing an extracted part of the downlink test signal 3b to be transmitted to the GSM terminal 2 to be tested in the GSM pseudo base station apparatus 10a of the first embodiment. In the GSM pseudo base station apparatus 10a, a data creation unit 11, a transmission unit 12, a dummy burst signal creation unit 13, an addition unit 14, and a dummy burst control unit 15 as a dummy signal control unit are provided.

In the data creation unit 11, the control data creation unit 16 sets the control channel 5a only in the first 0th slot among the 8th to 7th total slots constituting one frame in the downlink test signal 3b shown in FIG. The control data 7 of the signal level L _{1 to} be incorporated is created and sent to the switch 18.

Further, the communication data creation unit 17 should be incorporated into the communication channel 6a in 4 consecutive slots from the 2nd slot to the 5th slot among the total 8 slots of the 0th to 7th in the downlink test signal 3b shown in FIG. Then, communication data 9 having a signal level L ₂ lower than the signal level L ₁ of the control data 7 is generated and sent to the switch 18.

The switching control unit 19 performs switching control of the switch 18 for each of the 0th to 7th slots of one frame in the downlink test signal 3b shown in FIG. Specifically, in the first 0th slot of one frame, switching is performed to the control data creating unit 16 side, and from the second slot to the fifth slot of one frame is switched to the communication data creating unit 17 side. As a result, the switch 18 outputs the data in which the control data 7 of the signal level L ₁ is incorporated in the 0th slot of one frame and the communication data 9 of the signal level L ₂ is incorporated in the second slot to the fifth slot. Is done.

Data obtained by time-division synthesis of the control data 7 and the communication data 9 output from the data creation unit 11 is channel-coded by the channel synthesis unit 20 in the transmission unit 12 and then GMSK-modulated by the modulator 21. Thereafter, in the RF unit 22, the frequency (carrier frequency) of the control data 7 is set to the first frequency f ₁ using the frequency supplied from the first oscillator 23, and the frequency (carrier frequency) of the communication data 9. Is set to the second frequency f ₂ and transmitted as the transmission signal 24 to the next adder 14.

A specific method for setting the frequencies of the control data 7 and the communication data 9 to the first and second frequencies f ₁ and f ₂ using the first oscillator 23 will be described. The switching control unit 19 of the data creation unit 11 switches the switch 18 to the control data creation unit 16 side in the first 0th slot in one frame and sets the oscillation frequency of the first oscillator 23 to the first frequency f _1. Then, the first frequency f ₁ is supplied to the RF unit 22. Further, the switching control unit 19 switches the switch 18 to the communication data creation unit 17 side from the second slot to the fifth slot in one frame, and sets the oscillation frequency of the first oscillator 23 to the second frequency f ₂ . Then, the first frequency f ₂ is supplied to the RF unit 22.

  The switching control unit 19 stops the operation of the first oscillator 23 in the first slot, the sixth slot, and the seventh slot. As a result, the data 7 and 9 are not output in the first slot, the sixth slot, and the seventh slot in the transmission signal 24 output from the transmission unit 12.

  In the dummy burst signal generation unit 13, the dummy burst generation unit 25 is a combination data code [1, 1, 1, 1 of “0” and “1” predetermined in the standard (3GPP TS 45.002) described above. , 1.0, 1, 1, 0, ...], the dummy burst 28 shown in FIG. 3 is created.

The dummy burst 28 created by the dummy burst creating unit 25 is GMSK modulated by the next modulator 26. Thereafter, the RF section 27, by using the first frequency f ₁ supplied from the second oscillator 29, the frequency of the dummy burst 28 (carrier frequency) is set to a first frequency f _1, the dummy burst signal 30 is sent to the next adder 14.

  The signal level of the dummy burst 28 created by the dummy burst creating unit 25 and the duration of the signal level are given by the dummy burst control unit 15. The dummy burst control unit 15 monitors the creation state of the control data 7 and the communication data 9 in each of the 0th to 7th slots by the switching control unit 19 in the data creation unit 11 and selects them in advance by the tester. The dummy burst creation operation (creation conditions) of the dummy burst creation unit 25 is designated in accordance with the determined method.

In the GSM pseudo base station apparatus 10a of the first embodiment, the signal level is the specified signal level L _S predetermined in the standard [3GPP TS 45.008]. The duration of the specified signal level L _S is one frame, that is, the dummy burst 28 is always output.

Therefore, according to the first embodiment, the control data 7 of the same first frequency f ₁ and the dummy burst 28 overlap in the 0th slot in one frame, but the signal level L ₁ of the control data 7 is Since it is much higher than the prescribed signal level L _S of the dummy burst 28, there is no problem in reading the control data 7 performed by the GSM terminal 2 to be tested.

  The adder 14 adds the transmission signal 24 output from the transmitter 12 and the dummy burst signal 30 output from the dummy burst signal generator 13, and sends the result as a downlink test signal 3b to the GSM terminal 2 to be tested.

Figure 3 is a format diagram of a first control channel 5a frequency f _1, a second communication channel 5b of the frequency f _2, the first frequency f ₁ of the dummy burst 28 included in the downlink test signal 3b. As can be understood in this format diagram, the control channel 5a is only control data 7 of the signal level L ₁ are included, the communication channel 6a is included only communication data 9 of the signal level L _2. Furthermore, a dummy burst 28 having a prescribed signal level L _S exists over the entire frame.

  In the GSM pseudo base station apparatus 10a of the first embodiment configured as described above, the GSM terminal 2 to be tested that receives the downlink test signal 3b shown in FIG. 3 output from the GSM pseudo base station apparatus 10a is 1 It becomes possible to detect the signal level of the dummy burst 28 in any slot among the total of eight slots from the 0th to the seventh in the frame.

In this case, not only the GSM terminal 2 in which the reception frequency is changed by one receiving circuit, but also the GSM in a format in which the signals of the first and second frequencies f ₁ and f ₂ are individually received by the two receiving circuits. The terminal 2 can also be supported.

In this case, like the conventional GSM pseudo base station apparatus 10 shown in FIG. 8, the control data 7 and the communication data 9 are created, and these are time-division combined according to the time slot, and the oscillation frequency is generated by one oscillator 23. Is switched to the first and second frequencies f ₁ and f ₂ , and the respective frequencies of the control data 7 and the communication data 9 subjected to time division synthesis are set to the first and second frequencies f ₁ and f ₂ , respectively. A signal 24 is obtained.

  Then, the dummy burst signal creation unit 13 creates a dummy burst signal 30 independently of the data creation unit 11, the addition unit 14 adds the transmission signal 24 and the dummy burst signal 30, and the dummy burst 28. The downlink test signal 3b shown in FIG.

  As described above, the purpose of using the dummy burst 8 of the downlink signal 3 output from the regular base station 1 is to determine whether the control channel 5 of the received downlink signal 3 satisfies the lower limit signal level in the GSM terminal 2. Since it is used only for determination, high levels of frequency accuracy, level accuracy, and waveform quality of the dummy burst 8 are not required.

Therefore, in the GSM pseudo base station apparatus 10a of the first embodiment, the second oscillator 29 for creating the dummy burst 28 having the same first frequency f ₁ as the control channel 5a can be configured at a low cost. Therefore, not only the voice call function but also the electronic mail function, the data transmission function, the packet communication function, etc. without significantly increasing the manufacturing cost of the GSM pseudo base station apparatus 10a while maintaining the high test function for the GSM terminal 2 It is possible to improve the test function for the GSM terminal 2 having the advanced functions.

(Second Embodiment)
FIG. 4 is a format diagram of the downlink test signal 3c transmitted from the GSM pseudo base station apparatus according to the second embodiment of the present invention to the GSM terminal 2 to be tested. The block configuration diagram of the GSM pseudo base station apparatus of the second embodiment is the same as the block configuration diagram of the GSM pseudo base station apparatus 10a of the first embodiment shown in FIG.

In the GSM pseudo base station apparatus of the second embodiment, the dummy burst control unit 15 in FIG. As shown in FIG. 4, the control data 7 of the control channel 5 a and the communication data 9 of the communication channel 6 a that are sequentially generated in the slots are monitored, and in the first to seventh slot periods in which the control data 7 is not transmitted. Furthermore, the output level of the dummy burst 28a is set to, for example, the same reference level L _{1 as} that of the control data 7, which exceeds the specified signal level L _S defined by the above-mentioned standard.

  Note that the signal level of the 0th slot is 0 level, that is, the second oscillator 29 is stopped in the 0th slot in which the control data 7 in one frame is transmitted.

  Also in the GSM pseudo base station apparatus of the second embodiment configured as described above, the GSM terminal 2 to be tested that has received the downlink test signal 3c shown in FIG. 4 output from the GSM pseudo base station apparatus 10a is one frame. Since the signal level of the dummy burst 28a can be detected in any one of the first to seventh slots other than the 0th slot from which the control data 7 is transmitted, It is possible to achieve substantially the same operational effects as the GSM pseudo base station apparatus 10a of the first embodiment described above.

Further, in the second embodiment, the dummy burst 28a is not transmitted in the 0th slot in which the control data 7 is transmitted, and the signal level of the dummy burst 28a in the slot other than the control data 7 is controlled by the control data. since set equal to 7 the signal level L ₁ of, downstream test signal 3c including communication channel 6a and the control channel 5a and the dummy burst 28a shown in FIG. 4 are transmitted from the base station 1 of the normal to the GSM terminal 2 This is equivalent to the regular downstream signal 3 shown in FIG.

  Therefore, the GSM pseudo base station apparatus of the second embodiment can perform various tests on the GSM terminal 2 to be measured in a state that is as close as possible to the actual use state.

(Third embodiment)
FIG. 5 is a format diagram of the downlink test signal 3d transmitted from the GSM pseudo base station apparatus according to the third embodiment of the present invention to the GSM terminal 2 to be tested. The block configuration diagram of the GSM pseudo base station apparatus of the third embodiment is the same as the block configuration diagram of the GSM pseudo base station apparatus 10a of the first embodiment shown in FIG.

  In the GSM pseudo base station apparatus of the third embodiment, the dummy burst control unit 15 in FIG. The control data 7 of the control channel 5a and the communication data 9 of the communication channel 6a, which are sequentially created in the slot, are monitored, and the output of the dummy burst 28b is sent to the first to seventh control data 7 of which the control channel 5a is not transmitted. In each slot period, the output of the dummy burst 28b can be set to, for example, an arbitrary output pattern designated by the slot unit operated and input by the tester.

For example, in the third embodiment, as shown in FIG. 5, the signal level of the dummy burst 28b for one frame is set to three types (0, L _L , L _S , L ₁ , L ₃ in order from the bottom (0 If the level is included, it is set to 5 types).

  In such a GSM pseudo base station apparatus of the third embodiment, the pattern of the output level for one frame in the dummy burst 28 can be arbitrarily set. Therefore, as the GSM pseudo base station apparatus, the dummy burst 28b of the GSM terminal 2 is used. It is possible to carry out various tests such as detection of the execution timing of level detection and detection of reception sensitivity in each time slot within one frame.

  The present invention is not limited to the above-described embodiments. The dummy burst creating unit 25 can create a dummy burst using, for example, a pseudo-random code string.

  Further, the dummy burst can be made an unmodulated signal. In this case, since the dummy burst creating unit 25 and the modulator 26 are not required, the GSM pseudo base station apparatus 10a with a reduced manufacturing cost can be realized as compared with the GSM pseudo base station apparatus of the first embodiment.

The schematic diagram which shows the connection state of the GSM pseudo base station apparatus concerning 1st Embodiment of this invention, and the GSM terminal of a test object The block diagram which shows schematic structure of the GSM pseudo base station apparatus of the first embodiment Format diagram of downlink test signal transmitted from GSM pseudo base station apparatus of first embodiment to test target GSM terminal Format diagram of downlink test signal transmitted from GSM pseudo base station apparatus of second embodiment of the present invention to test target GSM terminal Format diagram of downlink test signal transmitted from GSM pseudo base station apparatus of third embodiment of the present invention to GSM terminal to be tested Schematic diagram showing the relationship between a base station and a GSM terminal in a GSM mobile communication system Format diagram of downlink signal transmitted from base station to GSM terminal Schematic diagram showing a connection state between a conventional GSM pseudo base station apparatus and a GSM terminal to be tested Format diagram of downlink test signal transmitted from the conventional GSM pseudo base station apparatus to the GSM terminal to be tested

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Base station, 2 ... GSM terminal, 3 ... Downlink signal, 3a, 3b, 3c, 3d ... Downlink test signal, 4, 4a ... Uplink signal, 5, 5a ... Control channel, 6, 6a ... Communication channel, 7 ... Control data 8, 28, 28a, 28b ... dummy burst, 9 ... communication data, 10, 10a ... GSM pseudo base station apparatus, 11 ... data creation unit, 12 ... transmission unit, 13 ... dummy burst signal creation unit, 14 ... Adder, 15 ... Dummy burst controller, 16 ... Control data generator, 17 ... Communication data generator, 18 ... Switch, 19 ... Switch controller, 20 ... Channel combiner, 21,26 ... Modulator, 22, 26 ... RF unit, 23 ... first oscillator, 24 ... transmission signal, 25 ... dummy burst creation unit, 29 ... second oscillator, 30 ... dummy burst signal

Claims (6)

A GSM pseudo base station apparatus (10a) that transmits a downlink test signal composed of a control channel including control data and a communication channel including communication data to the GSM terminal (2) to be tested, and tests the GSM terminal. In
A data creation unit (11) that creates the control data and the communication data, and synthesizes and outputs the created control data and communication data according to time slots;
The frequency of the control data and the communication data, which are time-division combined and output from the data generator, is supplied from the first oscillator (23) by switching the oscillation frequency. A transmission unit (12) that sets the second frequency and outputs it as a transmission signal (24);
A dummy signal generator (13) for generating a dummy signal (30) having a first frequency from the second oscillator (29);
A dummy signal control unit (15) for determining the output level of the dummy signal created by the dummy signal creating unit;
An addition unit (14) that adds the transmission signal output from the transmission unit and the dummy signal output from the dummy signal creation unit and transmits the result as the downlink test signal to the GSM terminal to be tested; A GSM pseudo base station apparatus characterized by the above. A GSM pseudo base station apparatus (10a) that transmits a downlink test signal composed of a control channel including control data and a communication channel including communication data to the GSM terminal (2) to be tested, and tests the GSM terminal. In
A data creation unit (11) that creates the control data and the communication data, and synthesizes and outputs the created control data and communication data according to time slots;
The frequency of the control data and the communication data, which are time-division combined and output from the data generation unit, is supplied from the first frequency (1) by switching the oscillation frequency from one first oscillator (23). A transmission unit (12) that sets the second frequency and outputs it as a transmission signal (24);
A dummy signal generator (13) for generating a dummy signal (30) having a first frequency from the second oscillator (29);
A dummy signal control unit (15) for determining an output level of the dummy signal created by the dummy signal creation unit and a duration of the output level;
An addition unit (14) that adds the transmission signal output from the transmission unit and the dummy signal output from the dummy signal creation unit and transmits the result as the downlink test signal to the GSM terminal to be tested; A GSM pseudo base station apparatus characterized by the above.   3. The GSM pseudo base station apparatus according to claim 2, wherein the dummy signal control unit constantly outputs a dummy signal having a predetermined signal level.   3. The dummy signal control unit sets the output level of the dummy signal to a value exceeding a predetermined specified signal level during a period in which control data of the control channel is not transmitted. GSM pseudo base station apparatus.   3. The dummy signal control unit sets the output of the dummy signal to an arbitrary output pattern specified in units of time slots in a plurality of time slots constituting one frame of the control channel. GSM pseudo base station apparatus.   6. The GSM according to claim 2, wherein the dummy signal creating unit creates the dummy signal based on a predetermined combination data code of “0” and “1”. Pseudo base station device.

Images