JP5692803B2 - Relay amplifier, relay amplifier control method, and program - Google Patents

Description

  The present invention relates to a relay amplification device, a relay amplification device control method, and a program.

A downlink amplification unit that relays and amplifies the downlink radio signal received by the base station side antenna and supplies it to the mobile station side antenna, and relays and amplifies the uplink radio signal received by the mobile station side antenna and supplies it to the base station side antenna An example of a relay amplifying device including an upstream amplification unit is disclosed in Patent Document 1.
In the relay amplification device of Patent Document 1, a part of each of the downlink radio signal and the uplink radio signal in the operation band is detected, and if a certain reference value is exceeded, the abnormal oscillation state is determined.

Japanese Patent Laid-Open No. 11-225102

  However, the relay amplifying apparatus of Patent Document 1 has a drawback that when the downlink radio signal and the uplink radio signal are excessive including the carrier, there is a defect that it is erroneously determined as abnormal oscillation although it is not in an abnormal oscillation state. When the oscillation state continues for a long time, it may lead to failure or deterioration of the upstream amplification unit and the downstream amplification unit.

  An object of the present invention is to provide a relay amplification device, a relay amplification device control method, and a program capable of accurately detecting an abnormal oscillation state and avoiding the abnormal oscillation state.

In order to achieve the above object, a relay amplifying device according to the first aspect of the present invention provides:
A downlink amplification unit that amplifies the downlink radio signal received by the first antenna and supplies the amplified signal to the second antenna;
An upstream amplification unit that amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna;
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detecting means for detecting;
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detecting means for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection means for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
It is characterized by providing.

In order to solve the above object, a relay amplification apparatus control method according to a second aspect of the present invention includes:
A downlink amplifying unit that amplifies the downlink radio signal received by the first antenna and supplies it to the second antenna, and amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna For a relay amplification device comprising an upstream amplification unit,
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detection processing to detect,
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detection processing for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection process for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
It is characterized by performing.

In order to achieve the above object, a program according to the third aspect of the present invention provides:
On the computer,
A downlink amplifying unit that amplifies the downlink radio signal received by the first antenna and supplies it to the second antenna, and amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna For a relay amplification device comprising an upstream amplification unit,
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detection processing to detect,
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detection processing for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection process for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
It is characterized by making it carry out.

  The present invention can accurately detect an abnormal oscillation state and can avoid an abnormal oscillation state.

1 is a configuration diagram illustrating a relay amplification apparatus according to a first embodiment of the present invention. It is a block diagram which shows the structure of an oscillation detection part. It is a figure which shows the pass-band characteristic of BPF. It is a block diagram which shows the structure of an arithmetic processing part. (A) shows that the frequency characteristic of the thermal noise in the downstream operation band in the normal state is flat, and (b) shows the abnormal oscillation state due to a decrease in the coupling amount between both antennas. It is a figure which shows that the frequency characteristic of the thermal noise in a downstream operation | use band becomes a vibration state (pseudo sine wave state). (A) shows the case where the frequency characteristics of thermal noise in the downstream operation band in the normal state are flat and carriers exist, and (b) shows the downstream operation in the abnormal oscillation state. It is a figure which shows the case where the frequency characteristic of the thermal noise in a band is a vibration state (pseudo sine wave state), and a carrier exists. It is a flowchart for demonstrating operation | movement of a relay amplification apparatus. It is a block diagram which shows the relay amplifier apparatus which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structure of an oscillation detection part.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIG. 1 is a configuration diagram illustrating a relay amplification apparatus according to the first embodiment of the present invention.
This relay amplifying apparatus includes an antenna 1 that is a base station antenna, a duplexer (hereinafter referred to as DUP) 2 that demultiplexes downlink and uplink radio signals and outputs a downlink radio signal, and an amplifying unit that amplifies the downlink radio signal 3. A coupler 4 is connected to the output side of the amplifying unit 3.

  The coupler 4 transmits the downlink radio signal amplified by the amplifying unit 3 to a band-pass filter (hereinafter referred to as BPF) 5 with almost no loss, and a part thereof serves as an oscillation detecting unit 6. The downlink radio signal extracted from the coupler 4 and applied to the oscillation detection unit 6 is set to have a value of about −10 dB. The BPF 5 limits the bandwidth of the downlink operation band. On the output side of the BPF 5 is connected a variable amplifying unit 7 that can amplify the band-limited downlink radio signal and vary the gain. An arithmetic processing unit 8 is connected to the output side of the oscillation detection unit 6.

On the output side of the variable amplifying unit 7, similarly to DUP 2, a DUP 9 that demultiplexes the downlink radio signal and the uplink radio signal and outputs the downlink radio signal is connected. The DUP 9 is connected to an antenna 10 that radiates a sufficiently amplified downstream radio signal.
The DUP 2, the amplifying unit 3, the BPF 5, the variable amplifying unit 7, and the DUP 9 constitute a downlink system amplifying unit.

The DUP 9 is connected to an amplifying unit 11 that amplifies the uplink radio signal demultiplexed by the DUP 9. A BPF 12 that limits the bandwidth of the upstream operation band is connected to the output side of the amplification unit 11, and a variable amplification unit 13 that amplifies the uplink radio signal band-limited by the BPF 12 and varies the gain is connected to the output side of the BPF 12. ing. The output side of the variable amplification unit 13 is connected to DUP2.
The DUP 9, the amplification unit 11, the BPF 12, the variable amplification unit 13, and the DUP 2 constitute an upstream amplification unit. The gains of the downlink amplifying unit and the uplink amplifying unit are set to the same value.

The oscillation detection unit 6 detects a mixed signal of the output signal of the coupler 4 and a local signal having a frequency designated according to a channel designation signal described later, with a narrow band limitation.
FIG. 2 is a block diagram illustrating a configuration of the oscillation detection unit 6.
The oscillation detection unit 6 includes a mixing unit 61, a synthesizer unit 62, and a reference signal generation unit 63.

A part of the downlink radio signal (for example, the operation band 2110 to 2120 MHz) supplied from the coupler 4 is input to one input terminal of the mixing unit 61.
The reference signal generator 63 generates a 5.12 MHz reference signal that is an integral multiple of 200 KHz, which is the same as the channel designation interval. The synthesizer unit 62 is connected to the output side of the reference signal generation unit 63.

  The synthesizer 62 generates a local signal of, for example, 2060 to 2070 MHz having a frequency specified by a channel specifying signal described later supplied from the arithmetic processing unit 8 with reference to the reference signal from the reference signal generating unit 63. The local signal generated by the synthesizer unit 62 is input to the other input terminal of the mixing unit 61.

  A BPF 64 is connected to the output side of the mixing unit 61. The mixing unit 61 outputs, for example, 50 MHz, which is a frequency difference component between the local signal and the downlink radio signal. The frequency difference component is band-limited to a narrower band than the BPF 64, and then detected by a detection unit 65 that includes a detection diode (not shown), a load resistor, and a smoothing capacitor to generate a DC voltage.

FIG. 3 shows the passband characteristics of the BPF 64, where the horizontal axis represents frequency and the vertical axis represents attenuation.
The BPF 64 has a characteristic of band-limiting to a narrow band having a center frequency of 50 MHz and a pass bandwidth of 100 KHz. The reason why the passband width is set to a narrow band of 100 KHz is to accurately detect the energy level of each frequency point (especially the inclined portion) of the pseudo sine wave described later and analyze the pseudo sine wave. Because it is necessary. Such a BPF 64 can be composed of a SAW filter.
In this embodiment, the frequency of the local signal is set so that the frequency difference is 50 MHz. However, 40 MHz or 60 MHz may be used as long as the BPF 64 can realize a narrow bandwidth of 100 KHz or less.

  A detector 65 is connected to the BPF 64. The detection unit 65 detects the output signal of the BPF 64. The signal converted into a DC voltage by the detection unit 65 is sent to the arithmetic processing unit 8. The arithmetic processing unit 8 continuously sends a channel designation signal to the oscillation detection unit 6 and records and outputs the output signal of the oscillation detection unit 6 and controls the variable amplification units 7 and 13 depending on the calculation result. It has a function to send a signal.

FIG. 4 is a block diagram showing a configuration of the arithmetic processing unit 8.
The arithmetic processing unit 8 includes a CPU 81.
The CPU 81 receives the reference signal from the reference signal generation unit 63 and sends a channel designation signal synchronized with the reference signal to the synthesizer unit 62 of the oscillation detection unit 6. Here, the channel designation signal refers to a channel data (frequency division number) signal, a clock signal, and a strobe signal. In this embodiment, in order to designate a channel at 200 KHz intervals over 10 MHz of 2060 to 2070 MHz every 100 ms, a channel designation signal is sequentially transmitted. That is, 2060.0 MHz for the first time, 2060.2 MHz for the second time, 2060.4 MHz for the third time,..., 2070.0 MHz for the 51st time, so that the synthesizer unit 62 sequentially outputs the channel designation. Do.

  The detection voltage output from the detection unit 65 of the oscillation detection unit 6 is analog / digital converted by the A / D converter 82 and input to the CPU 81 as data DATA. Since one data DATA is input for each channel designation, a total of 51 data DATA is input when 10 MHz is swept. The CPU 81 sequentially stores the input data DATA and the specified frequency of the channel specifying signal in the RAM 83, and analyzes the maximum value (MAX value) and minimum value (MIN value) of the output signal of the detector 65, and determines the MAX value. It is constantly monitored whether the difference in the MIN values is greater than a certain threshold (for example, 0.5 V). For example, if the MAX value is 1.5V and the MIN value is 1.0V, the difference is 0.5V, which exceeds the threshold value.

  When the threshold value is exceeded, the difference between the frequency when the MAX value is obtained and the frequency when the MIN value is obtained is a value calculated from the absolute group delay amount (in this example, 1 MHz). Determine whether they match. If they coincide with each other, it is determined that the oscillation state is abnormal, and the CPU 81 sends an alarm and sends a control signal to the D / A converters 8484 and 85 so that the digital / analog converted control voltage is supplied to the variable amplifier 7. , 13.

Next, the abnormal oscillation state will be described.
FIG. 5A shows that the frequency characteristic of the thermal noise (KTBF + G) in the downstream operation band in the normal state is flat. The horizontal axis is the downstream frequency, and the vertical axis is the output level.

The level of thermal noise is determined by KT: Boltzmann constant (−174 dBm / Hz), B: bandwidth, F: noise figure (NF), G: gain.
B differs depending on the communication system, and is a constant value of 1.23 MHz in the case of NCDMA (Narrowband Code Division Multiple Access) and 3.84 MHz in the case of WCDMA (Wideband Code Division Multiple Access). NF is a constant value determined by the insertion loss of DUP2 and the noise figure of the amplifying unit 3, and G is the total gain obtained by subtracting the insertion loss of DUP2, BPF5, and DUP9 from the combined gain of the amplifying unit 3 and the variable amplifying unit 7. It is a fixed value. Therefore, the level of thermal noise in a normal state is always stable and does not fluctuate.

  FIG. 5B shows that the frequency characteristics of the thermal noise in the downstream operation band in the abnormal oscillation state due to a decrease in the coupling amount between the two antennas becomes a vibration state (pseudo sine wave state). Yes.

  When the output of the antenna 10 is fed back to the antenna 1, the amplified output is delayed by the absolute group delay amount. The amplified output is fed back to the antenna 1 and delayed and amplified. By repeating this, a pseudo sine wave state is obtained and a stable state such as a standing wave is obtained. Therefore, the frequency component of the pseudo sine wave is the same as the reciprocal of the absolute group delay amount (downstream absolute delay amount from antenna 1 to antenna 10).

  That is, if the absolute group delay amount is, for example, 500 ns, one period is 500 ns, so the frequency component of the pseudo sine wave is 2 MHz. If the operating bandwidth is 10 MHz, a pseudo sine wave of 5 cycles will be generated.

  If the absolute group delay amount is 1000 ns (1 μs), the frequency component of the pseudo sine wave is 1 MHz, and a 10-cycle pseudo sine wave is generated within the operating bandwidth of 10 MHz. The absolute group delay amount occurs also in DUP2 and DUP9, but BPF5 is mainly dominant, and as the number of stages of BPF5 increases and the characteristics become steeper, the absolute group delay amount increases.

  If the coupling amount between the antennas 1 and 10 is further reduced and deteriorated, the level of thermal noise increases and the amplitude of the pseudo sine wave increases, but the frequency component does not change. Here, although the downlink system is described, the uplink system is in the same state when the coupling amount is deteriorated.

  FIG. 6A shows a case where the frequency characteristics of thermal noise in the downstream operation band in a normal state are flat and carriers exist. The horizontal axis is the downstream frequency, and the vertical axis is the output level.

  FIG. 6B shows a case where the frequency characteristic of the thermal noise in the downstream operation band in the abnormal oscillation state is the vibration state (pseudo sine wave state) and the carrier exists. The magnitude of the thermal noise level does not vary depending on the presence or absence of carriers.

Next, the operation of the relay amplification device in FIG. 1 will be described.
FIG. 7 is a flowchart for explaining the operation of the relay amplifying apparatus.

  First, the CPU 81 sets n for designating the channel number to 1, sets a channel designation signal so that the first channel CH1 is designated, and gives it to the oscillation detector 6 (step S1). The synthesizer 62 of the oscillation detection unit 6 receives a channel designation signal from the CPU 81 and outputs a local signal corresponding to the first channel CH1. The mixing unit 61 outputs a frequency difference component between the local signal and the downlink radio signal.

  The output signal of the mixing unit 61 is detected by the detection unit 65 after being band-limited to a narrower band than the BPF 64. The detection voltage output from the detection unit 65 is converted into digital data DATA1 corresponding to the channel CH1 by the A / D converter 82, and is supplied to the CPU 81. The CPU 81 receives data DATA 1 from the oscillation detection unit 6 and records it in the RAM 203. The frequency (CH1 frequency) indicated by the channel designation signal at that time is also recorded simultaneously (step S2). The CPU 81 determines whether the data DATA1 is equal to or less than a threshold value of 3.0 V (step S3).

  As shown in FIG. 6 (b), in the case where there is a carrier, only the common channel signal (a signal shared and used by a plurality of mobile stations) is received as the minimum carrier level in the mobile phone system. Therefore, it becomes a level higher than the thermal noise level. Therefore, in this embodiment, when the threshold value is set to 3.0 V and the input DATA1 is a value exceeding 3.0 V (step S3: NO), a position away from a bandwidth slightly larger than the occupied bandwidth of one carrier. Skip to specify a specific channel. That is, for example, a channel at a position separated by 1.4 MHz (for 7 channels) is skipped (n + 7), channel designation is performed (step S4), and the process returns to step S2. As a result, it is possible to invalidate this DATA value and avoid erroneously detecting an abnormal oscillation state due to the influence of the carrier.

  When the data DATAn input to the CPU 81 indicates 3.0V or less (step S3: YES), whether the data DATANn is a MAX value (maximum value) (step S5), a MIN value (minimum value) (step) S6) is determined. The analysis of the MAX value and the MIN value is performed and updated every time data DATAn is input to the CPU 81. After step S6, the MAX value-MIN value is calculated, and it is confirmed whether the MAX value-MIN value is 0.5 V or less (step S7). The confirmation in step S7 is performed every time data DATAn is input.

  If the MAX value−MIN value is 0.5 or less in the confirmation in step S7 (step S7: YES), n is incremented (step S8), and it is confirmed whether n has become 51 (step S9). If n is not 51 (step S9: NO), the process returns to step S1. If n is 51 (step S9: YES), in step S10, the data DATA1 to DATA51 in the RAM 83 and the channel data indicating the channels CH1 to CHn are cleared, and n is set to 1, and the process returns to step S1. (Step S10).

  When the MAX value−MIN value exceeds 0.5 in the confirmation in step S7 (step S7: NO), the difference between the frequency at which the data DATAn becomes the MAX value and the frequency at which the MIN value becomes 1 ± 0.2 MHz is determined. Confirm (step S11). This 1 ± 0.2 MHz is a value calculated from the absolute group delay amount, and corresponds to a half cycle in the frequency characteristic of the pseudo sine wave-like thermal noise. If the difference between the frequency at which the data DATAn becomes the MAX value and the frequency at which the data MIN value becomes is not 1 ± 0.2 MHz (step S11: NO), it is not an abnormal oscillation state, so the process proceeds to step S8.

  If the difference between the frequency at which the data DATAn becomes the MAX value and the frequency at which the data MIN value becomes 1 ± 0.2 MHz (step S11: YES), it is an abnormal oscillation state, so it is determined whether an alarm is being sent (step S11). S12). If the alarm is not being sent (step S11: NO), the gains of the variable amplifiers 7 and 13 are set to 20 dB (step S13), an alarm is sent (step S14), and the process proceeds to step S10.

  If the determination in step S12 is that an alarm is being sent (step S12: YES), the gains of the variable amplifiers 7 and 13 are set to 10 dB (step S15), and the process is terminated.

Next, advantages of this embodiment will be described.
A normal state in which the coupling amount α (dB) between the antenna 1 and the antenna 10 is larger than the total downlink gain β (dB) of the relay amplification device will be described. For example, when the coupling amount α is −80 dB and the total gain β is 70 dB, the equation −α <β is not satisfied, so that an abnormal oscillation state does not occur. Here, the total gain β is a value obtained by subtracting the insertion loss of DUP2, BPF5, and DUP9 from the gain obtained by adding the gain of the amplifier 3 and the gain of the variable amplifier 7.

  That is, in the normal state, as shown in FIG. 5A and FIG. 6A, the frequency characteristics of the thermal noise in the downstream operation band are flat, so that 51 pieces are sent from the oscillation detection unit 6 to the CPU 81. There is almost no level difference in DATA of 0.5V or less. For this reason, as shown in the flowchart of FIG. 7, there is a situation in which the main loop (normal flow of steps S1 to S10) is being looped, and no alarm is transmitted.

  On the other hand, when the coupling amount α (dB) between the antenna 1 and the antenna 10 is smaller than the total gain β (dB) of the downlink amplification unit of the relay amplification device and the abnormal oscillation state occurs, for example, the coupling amount α is −60 dB. When the total gain β is 70 dB, the equation satisfies −α <β, and an abnormal oscillation state occurs. In the abnormal oscillation state, a part of the output of the downlink radio signal radiated from the antenna 10 is fed back to the antenna 1 and amplified, and a part of the amplified component is fed back to the antenna 1 and amplified. A part of the output of the radiated upstream radio signal is fed back to the antenna 10 and amplified, and a part of the amplified component is fed back to the antenna 10 and amplified again, so that the downstream system (and the upstream system) is abnormal. It is an over-input state and an over-output state.

  In the abnormal oscillation state, as shown in FIGS. 5B and 6B, the frequency characteristics of the thermal noise in the downstream operation band become a vibration state (pseudo sine wave state). A level difference occurs in 51 pieces of data DATA sent from the oscillation detection unit 6 to the CPU 81. Since the analysis of the MAX value and the MIN value of the data DATA is performed and updated every time the DATA is input to the CPU 81, it is 0.5 V or more in 11 data DATA for one period (2 MHz). As soon as the difference occurs, the process proceeds to the frequency difference confirmation flow in step S11. That is, it is not necessary to acquire all 51 pieces of data DATA, and an oscillation abnormality can be detected by analyzing the top 11 pieces of data DATA at the shortest.

  Since the data DATA and the frequency are recorded in association with each other, the frequency difference between the MAX value and the MIN value can be easily calculated. If the frequency difference is found to be 1 ± 0.2 MHz, it is determined that the oscillation is abnormal due to the deterioration of the coupling amount between the antennas 1 and 10, and the CPU 81 sends the variable amplifiers 7 and 13 via the D / A converters 84 and 85. A control voltage is supplied and an alarm is sent out.

By reducing the respective gains of the variable amplifiers 7 and 13 from 30 dB to 20 dB, the total gain β of the downstream system becomes 60 dB, and an abnormal oscillation state is avoided.
Monitoring is continued even after the gains of the variable amplifiers 8 and 13 are set to 20 dB. When the difference between the MAX value and the MIN value is 0.5 V or more, the gain of the variable amplifiers 7 and 13 is increased from 20 dB to 10 dB. Can be reduced,

  As described above, the present embodiment has a function of detecting the frequency characteristic variation of the thermal noise in the downstream operation band of the relay amplifying device and a function of calculating the frequency component of the pseudo sine wave generated in the operation band. Then, the abnormal oscillation state due to the deterioration of the coupling amount between the two antennas 1 and 10 is accurately detected, and the gain of the downstream system and the upstream system is controlled to a preset small value to avoid the abnormal oscillation state. It is possible to avoid deterioration or failure of the downstream and upstream amplifying units due to a decrease in the subscriber capacity of the system or an excessive output state for a long time, and to issue an alarm.

[Second Embodiment]
FIG. 8 is a block diagram showing a relay amplifying device according to the second embodiment of the present invention. Elements common to those in FIG. 1 are given common reference numerals.
In this relay amplifying device, the coupler 4 of the first embodiment is omitted, and the coupler 14 and the oscillation detector 15 are provided.

  A BPF 5 is directly connected to the output side of the amplifying unit 3. A coupler 14 is connected to the output side of the amplifying unit 11. The coupler 14 has the same function as the coupler 4, and the output side of the coupler 14 is connected to the BPF 12 and the oscillation detector 15. The output side of the oscillation detector 15 is connected to the arithmetic processor 8. The arithmetic processing unit 8 provides a channel designation signal to the oscillation detection unit 15. Other configurations are the same as those of the first embodiment.

FIG. 9 is a block diagram illustrating a configuration of the oscillation detection unit 15.
The oscillation detection unit 15 includes a mixing unit 151, a synthesizer unit 152, and a reference signal generation unit 153.

A part of the uplink radio signal (for example, operation band 1920 to 1930 MHz) supplied from the coupler 14 is input to one input terminal of the mixing unit 151.
The reference signal generator 153 generates a reference signal. The synthesizer unit 152 is connected to the output side of the reference signal generator 153.

  The synthesizer unit 152 generates a local signal of, for example, 1870 to 1880 MHz having a frequency specified by the channel specifying signal supplied from the arithmetic processing unit 8 with reference to the reference signal from the reference signal generating unit 153. The local signal generated by the synthesizer unit 152 is input to the other input terminal of the mixing unit 151.

  A BPF 154 is connected to the output side of the mixing unit 151. The mixing unit 151 outputs, for example, 50 MHz of the frequency difference component between the local signal and the downlink radio signal. The frequency difference component is band-limited to a narrow band by the BPF 154 and then detected by the detection unit 155. The pass band of the BPF 154 is the same as the BPF 64 in FIG. 3, the center frequency is 50 MHz, and the pass band width is 100 KHz. An output terminal of the detection unit 155 is connected to the arithmetic processing unit 8.

This relay amplification device also performs the same operation as the relay amplification device of the first embodiment.
When the coupling amount α (dB) between the antenna 1 and the antenna 10 is larger than the total gain β (dB) of the uplink system of the relay amplification device, for example, in a normal state where the coupling amount α is −80 dB and the total gain β is 70 dB Does not match the equation of −α <β, and therefore does not enter an abnormal oscillation state.

  Here, the total gain β is a value obtained by subtracting the insertion loss of DUP2, BPF12, and DUP9 from the gain obtained by adding the amplification unit 11 and the variable amplification unit 13. As shown in FIG. 5 (a) and FIG. 6 (a), the frequency characteristics of the thermal noise in the upstream operation band are flat. Therefore, the 51 noises sent from the oscillation detection unit 15 to the CPU 81 of the arithmetic processing unit 6 are displayed. There is almost no level difference (voltage difference) in the data DATA, and it is 0.5 V or less. For this reason, as shown in the flowchart of FIG. 7, the main loop (the normal flow in steps S1 to S10) is in a circumstance, and no alarm is sent.

  On the other hand, when the coupling amount α (dB) between the antenna 1 and the antenna 10 is smaller than the total gain β (dB) of the uplink system of the relay amplification device, for example, the coupling amount α is −60 dB and the total gain β is 70 dB. In this case, since it matches the expression of -α <β, an abnormal oscillation state is set. In the abnormal oscillation state, as in the first embodiment, as shown in FIG. 5B and FIG. 6B, the frequency characteristics of the thermal noise in the operating band of the upstream amplification unit are in the oscillation state (pseudo Sinusoidal state).

  Since a level difference occurs in the data DATA sent from the oscillation detection unit 15 to the CPU 81, the MAX value-MIN value of the data DATA becomes 0.5 V or more, and the frequency difference between the MAX value and the MIN value is 1 MHz ± 0. If the frequency matches 2 MHz, it is determined that the oscillation is abnormal due to the deterioration of the coupling amount between the antennas 1 and 10, and the control voltage is supplied to the variable amplifiers 7 and 13 via the D / A converters 84 and 85 by the CPU 81 and an alarm is given. Is sent out. The respective gains of the variable amplifying units 7 and 13 are reduced from 30 dB to 20 dB, so that the total gain β of the upstream system becomes 60 dB and the abnormal oscillation state is avoided.

  Monitoring is continued even after the gains of the variable amplifiers 7 and 13 are set to 20 dB. When the difference between the MAX value and the MIN value is 0.5 V or more, the gain of the variable amplifiers 7 and 13 is changed from 20 dB to 10 dB. Can be reduced,

  As described above, also in the second embodiment, the function of detecting the frequency characteristic variation of the thermal noise in the upstream operation band of the relay amplification device and the frequency component of the pseudo sine wave generated in the operation band are calculated. The abnormal oscillation state due to the deterioration of the coupling amount between both antennas 1 and 10 is accurately detected, and the gains of the upstream and downstream amplification units are controlled to small preset values, and the abnormal oscillation state is determined. By avoiding this, it is possible to avoid deterioration or failure of the upstream system and downstream system amplifier due to a decrease in the subscriber capacity of the mobile phone system or an excessive output state for a long time, and an alarm can be issued.

  A part or all of the above-described embodiment can be described as in the following supplementary notes, but is not limited thereto.

(Appendix 1)
A downlink amplification unit that amplifies the downlink radio signal received by the first antenna and supplies the amplified signal to the second antenna;
An upstream amplification unit that amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna;
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detecting means for detecting;
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detecting means for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection means for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
A relay amplifying device comprising:

(Appendix 2)
The relay amplifying apparatus according to appendix 1, wherein the state detecting unit includes an alarm unit that generates an alarm when the downstream system amplifying unit and the upstream system amplifying unit detect that it is in an abnormal oscillation state.

(Appendix 3)
The state detection means comprises gain reduction means for reducing the gain of the downlink amplification section and the uplink amplification section when it is detected that the downlink amplification section and the uplink amplification section are in an abnormal oscillation state. The relay amplification device according to Supplementary Note 1 or 2.

(Appendix 4)
A downlink amplifying unit that amplifies the downlink radio signal received by the first antenna and supplies it to the second antenna, and amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna For a relay amplification device comprising an upstream amplification unit,
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detection processing to detect,
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detection processing for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection process for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
A method of controlling a relay amplifying apparatus comprising:

(Appendix 5)
5. The relay amplifying apparatus control method according to appendix 4, wherein an alarm process is performed to generate an alarm when the state detection process detects that the downstream system amplification unit and the upstream system amplification unit are in an abnormal oscillation state. .

(Appendix 6)
When the state detection process detects that the downstream system amplification unit and the upstream system amplification unit are in an abnormal oscillation state, a gain reduction process is performed to reduce the gain of the downstream system amplification unit and the upstream system amplification unit. The relay amplifier control method according to appendix 4 or 5.

(Appendix 7)
On the computer,
A downlink amplifying unit that amplifies the downlink radio signal received by the first antenna and supplies it to the second antenna, and amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna For a relay amplification device comprising an upstream amplification unit,
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detection processing to detect,
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detection processing for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection process for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
A program characterized by having

(Appendix 8)
The program according to appendix 7, wherein an alarm process is performed to generate an alarm when the state detection process detects that the downstream system amplification unit and the upstream system amplification unit are in an abnormal oscillation state.

(Appendix 9)
When the state detection process detects that the downstream system amplification unit and the upstream system amplification unit are in an abnormal oscillation state, a gain reduction process for reducing the gain of the downstream system amplification unit and the upstream system amplification unit is performed. The program according to appendix 7 or 8, which is characterized.

1,10 antenna 2,9 DUP
3,11 Amplifying part 4,14 Coupler 5,12 BPF
6, 15 Oscillation detection unit 7, 13 Variable amplification unit 8 Arithmetic processing unit

Claims (9)

A downlink amplification unit that amplifies the downlink radio signal received by the first antenna and supplies the amplified signal to the second antenna;
An upstream amplification unit that amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna;
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detecting means for detecting;
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detecting means for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection means for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
A relay amplifying device comprising:   2. The relay amplification device according to claim 1, wherein the state detection unit includes an alarm unit that generates an alarm when the downstream system amplifying unit and the upstream system amplifying unit detect that the system is in an abnormal oscillation state.   The state detection means comprises gain reduction means for reducing the gain of the downlink amplification section and the uplink amplification section when it is detected that the downlink amplification section and the uplink amplification section are in an abnormal oscillation state. The relay amplification device according to claim 1 or 2. A downlink amplifying unit that amplifies the downlink radio signal received by the first antenna and supplies it to the second antenna, and amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna For a relay amplification device comprising an upstream amplification unit,
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detection processing to detect,
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detection processing for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection process for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
A method of controlling a relay amplifying apparatus comprising:   5. The relay amplifying device control according to claim 4, wherein the state detection processing performs alarm processing for generating an alarm when the downstream amplification unit and the upstream amplification unit are detected as being in an abnormal oscillation state. Method.   When the state detection process detects that the downstream system amplification unit and the upstream system amplification unit are in an abnormal oscillation state, a gain reduction process is performed to reduce the gain of the downstream system amplification unit and the upstream system amplification unit. The relay amplifier control method according to claim 4 or 5. On the computer,
A downlink amplifying unit that amplifies the downlink radio signal received by the first antenna and supplies it to the second antenna, and amplifies the uplink radio signal received by the second antenna and supplies the amplified signal to the first antenna For a relay amplification device comprising an upstream amplification unit,
The frequency characteristic of the thermal noise within the operating band of the downstream amplification unit or the upstream amplification unit is monitored, and the amplitude of the pseudo sine wave when the frequency characteristic of the thermal noise changes from a flat state to a pseudo sine wave is obtained. Amplitude detection processing to detect,
The frequency characteristic of the pseudo sine wave when the frequency characteristic of the thermal noise in the operation band of the downstream system amplification unit or the upstream system amplification unit is changed from a flat state to a pseudo sine wave is monitored. Frequency component detection processing for detecting
When the detected amplitude of the pseudo sine wave exceeds a predetermined value, and the detected frequency component matches the value calculated from the absolute group delay amount of the downlink amplification unit and the uplink amplification unit, A state detection process for detecting that the downstream amplification unit and the upstream amplification unit are in an abnormal oscillation state;
A program characterized by having   8. The program according to claim 7, wherein an alarm process for generating an alarm is performed when the state detection process detects that the downstream system amplification unit and the upstream system amplification unit are in an abnormal oscillation state. 9.   When the state detection process detects that the downstream system amplification unit and the upstream system amplification unit are in an abnormal oscillation state, a gain reduction process for reducing the gain of the downstream system amplification unit and the upstream system amplification unit is performed. The program according to claim 7 or 8, characterized in that the program.

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