JPH0435236A - Monitor system for reception booster amplifier - Google Patents

Abstract

PURPOSE:To monitor a gain fluctuation of a reception booster amplifier accurately at a receiver apart via a high frequency coaxial line by providing a pilot detection means which detects a level of an obtained high frequency pilot signal and monitors the gain of the reception booster amplifier with respect to level fluctuation in response to a switching timing of a time division switch circuit. CONSTITUTION:High frequency pilot signals SOP, SPQ whose frequency differs from that of a received high frequency signal are alternately inserted to an input terminal and an output terminal of a reception booster amplifier 15 amplifying the received high frequency signal and the result is sent to a receiver 19 via a high frequency coaxial line 17 together with the high frequency signal. Thus, the high frequency pilot signal amplified by the reception booster amplifier 15 and the high frequency pilot signal not subject to any change are detected alternately by a pilot detection means 31 of the receiver 19 to measure the gain of the reception booster amplifier 15 corresponding to the level fluctuation. Thus, the receiver 19 surely discriminates the operating state including the gain of the reception booster amplifier 15 placed at a remote location.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to wireless reception facilities, broadcasting facilities, etc. where the antenna and the receiver are located remotely via a high frequency coaxial line, and which are installed near the antenna. The present invention relates to a method for monitoring a receiving booster amplifier for monitoring the gain of a receiving booster amplifier for high frequency amplification on the receiver side.

[Prior Art] Conventionally, in order to monitor the operating status of an amplifier placed far away from the receiver, such as a receiver booster amplifier, it has been necessary to connect a monitoring line separate from the signal path and connect it to a separate system. This method was common.

However, this method requires construction work to install a monitoring line, which increases costs. Therefore, as a method for directly monitoring without using a monitoring line, a method of monitoring the power supply state of an amplifier as shown in FIG. 4 is used.

In FIG. 4, a high frequency signal received by an antenna 11 is input to a band pass filter 13, and a high frequency signal of a predetermined frequency is extracted. This high frequency signal is amplified by a reception booster amplifier 15, transmitted through a high frequency coaxial line 17, and inputted to an input terminal of a receiver 19.

On the other hand, the configuration for supplying power to the reception booster amplifier 15 is that the reception booster amplifier 15 of the high frequency coaxial line 17
This is realized by a power source separation filter (PSF) 41 inserted on the receiver 19 side, a power source separation filter 43 inserted on the receiver 19 side, and a power source circuit 45 that outputs a predetermined direct current.

That is, the DC current output from the power supply circuit 45 is inserted into the high frequency coaxial line 17 via the power supply isolation filter 43, the DC current is extracted by the power supply isolation filter 41, and the DC current is connected to the power supply path 47 which is separate from the signal path. The signal is supplied to the reception booster amplifier 15 via the signal.

Note that the power supply separation filters 41 and 43 each have a function of allowing a high frequency signal to pass through as is and inserting or extracting a direct current.

In such a configuration, a current monitor circuit 49 is inserted between the power supply circuit 45 and the power supply isolation filter 43, and the current supplied to the reception booster amplifier 15 is passed through the current monitor circuit 4.
By detecting at 9, the operating state of the receiving booster amplifier 15 is monitored.

[Problems to be Solved by the Invention] However, the current monitor circuit 49 monitors the power supply current supplied to the transistors that constitute the reception booster amplifier 15, and in reality can only monitor the quality of the functional state of the transistors. Ta.

Furthermore, it has not been possible to determine the gain of the receiving booster amplifier 15 only from changes in current.

Therefore, it has been difficult for the receiver side to accurately judge the operating state of the receiving booster amplifier installed at a remote location.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for monitoring a receiving booster amplifier, which allows the receiver side to accurately determine the operating status of a receiving booster amplifier installed at a remote location, including its gain.

[Means for Solving the Problems] The monitoring method according to claim 1 includes a reception booster amplifier that amplifies a high frequency signal received by an antenna and sends it to a receiver connected via a high frequency coaxial line. a pilot signal generation circuit that generates a high frequency pilot signal with a frequency different from that of the signal; a time division switch circuit that alternately outputs the high frequency pilot signal to two output terminals;
Two combining circuits insert the high-frequency pilot signal taken out from each output terminal into the input and output ends of the receiving booster amplifier, respectively, and the high-frequency pilot signal is separated from the input end of the receiver, and the level of the high-frequency pilot signal obtained is and pilot detection means for monitoring the gain of the receiving booster amplifier from level fluctuations corresponding to the switching timing of the time division switch circuit.

The invention set forth in claim 2 is the receiving booster amplifier monitoring method set forth in claim 1, in which a reference signal insertion means for inserting a reference signal into the high frequency coaxial line is provided on the receiver side in place of the pilot signal generation circuit. The receiving booster amplifier side is equipped with pilot signal generating means for detecting a reference signal transmitted via a high frequency coaxial line and generating a predetermined high frequency pilot signal from the obtained reference signal.

[For production]

The invention according to claim 1 inserts a high frequency signal and a high frequency pilot signal having different frequencies alternately into the input end and the output end of a receiving booster amplifier that amplifies the received high frequency signal, and transmits the high frequency signal through a high frequency coaxial line. It is transmitted to the receiver side along with the high frequency signal.

Therefore, the pilot detection means on the receiver side receives the high frequency pilot signal amplified by the reception booster amplifier,
The intact high-frequency pilot signal is detected alternately, and the gain of the receiving booster amplifier corresponding to the level fluctuation can be measured.

The invention according to claim 2 transmits a reference signal from the receiver side to the reception booster amplifier side via a high frequency coaxial line, detects this reference signal on the reception booster amplifier side and generates a high frequency pilot signal, and the like. The gain of the receiving booster amplifier can be measured in the same manner by making the configuration the same as that of the invention described in claim 1.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the invention as set forth in claim 1.

In the figure, the arrangement of the antenna 11, bandpass filter 13, reception booster amplifier 15, high frequency coaxial line 17, and receiver 19 is similar to the conventional configuration described above.

The feature of the present invention is that in this embodiment, the pilot signal generation circuit 21 generates a predetermined high frequency pilot signal S0, and the high frequency pilot signal S0 is alternately outputted to two output terminals P and Q. A high frequency pilot signal S is taken out to the split switch circuit 23 and the output terminal P. 2 to the output of the bandpass filter 13, a synthesis circuit 27 that synthesizes the high frequency pilot signal S0° taken out at the output terminal Q to the output of the receiving booster amplifier 15, and A high frequency pilot signal S is inserted. A branching circuit 29 that separates P and high-frequency pilot signal S0°, a receiving booster amplifier 15 that detects the separated high-frequency pilot signal
A pilot detection circuit 31 is provided to measure the gain of the pilot detector.

Note that the high-frequency pilot signal S0 is set to a frequency that is outside the frequency band of the high-frequency signal extracted by the band-pass filter 13 or that does not match that frequency.

In addition, the time division switch circuit 23 here alternately outputs the high frequency pilot signal S every one second. shall be switched. Therefore, for example, 0 to 1 second is 1. High frequency pilot signal S. 2 is combined into a high frequency signal on the input side of the reception booster amplifier 15, amplified together with the high frequency signal, and taken into the pilot detection circuit 31 via the high frequency coaxial line 17 and the branching circuit 29. In addition, for seconds t~2, the high frequency pilot signal S0° is synthesized with the high frequency signal amplified on the output side of the receiving booster amplifier 15, and is passed through the high frequency coaxial line 17 and the branching circuit 29 to the pilot detection circuit 3.
1.

Here, if the gain of the receiving booster amplifier 15 is A, then
High frequency pilot signal S OF combined with high frequency signal
is multiplied by A in the reception booster amplifier 15, and the high frequency pilot signal S0° combined with the high frequency signal output from the reception booster amplifier 15 is transmitted as is.

Further, if the loss from the output terminal P of the time division switch circuit 23 to the pilot detection circuit 31 is α1, and the loss from the output terminal Q of the time division switch circuit 23 to the pilot detection circuit 31 is αQ, then the pilot detection circuit 31 detects the loss. level S' of each high frequency pylond signal. 6, S'.

. is S'. p = A-S or α2
...(1)S. . -S,,cxo
...(2).

FIG. 2 shows level fluctuations according to each high frequency pilot signal SL, P, S0° detected by the pilot detection circuit 31.

That is, ■ is a high frequency pilot signal S. P's level S
'. , where ■ is the level S' of the high frequency pilot signal s0°. . shows.

Therefore, the level S' of each high frequency pilot signal. 2
, S'. . Taking the ratio of , we get SOP・αP=SOO・αo −(4
), each high frequency pilot signal SOP, So.

If we adjust the level of A=β...(5)
Therefore, the gain A of the receiving booster amplifier 15 (Fig. 2, ■
) can be measured.

Incidentally, level fluctuations in the high frequency pilot signal S0 outputted by the pilot signal generation circuit 21 are canceled out by the process of taking the ratio of the high frequency pilot signals SOP and S6Q, making it possible to accurately and stably measure the gain of the receiving booster amplifier 15. can.

Furthermore, by measuring each high frequency pilot signal SOP, S.0 in advance, it is also possible to measure the transmission losses (α7, α0) of the high frequency coaxial line 17 and others.

FIG. 3 is a block diagram showing the configuration of an embodiment of the invention according to claim 2.

In the figure, the feature of this embodiment is that instead of two pilot signal generation circuits, a reference signal oscillator 33 that generates a reference signal Sc is installed on the receiver 19 side, and this reference signal S is transmitted to a high frequency coaxial line 17. A combining circuit 35 to be inserted, a receiving booster amplifier 15, a branching circuit 37 to separate the reference signal Sc transmitted through the high frequency coaxial line 17, and a separated reference signal S
A frequency synthesis circuit 39 is provided which takes in the signal S0 and generates a high frequency pilot signal S0. Note that the frequency synthesis circuit 39 can be realized by a frequency multiplier circuit or a synthesizer.

The other configurations are the same as in the first embodiment.

That is, the configuration of this embodiment is such that the reference signal S is sent from the reference signal oscillator 33 on the receiver 19 side to the frequency synthesis circuit 39 on the receiving booster amplifier 15 side via the high frequency coaxial line 17.
The high frequency pilot signal S0 can be generated and inputted to the time division switch circuit 23, and the gain of the receiving booster amplifier 15 can be measured in the same manner.

Note that since the reference signal oscillator 33 is located on the receiver 19 side,
For example, if the reference signal oscillator 33 is used as a source oscillator and a synchronous detection method is applied to the pilot detection circuit 31, even if the high-frequency pilot signal has an extremely low level, it is possible to easily detect the level fluctuation. Accurate and stable gain measurements can be performed.

〔Effect of the invention〕

As described above, the present invention allows the gain fluctuations of the receive booster amplifier to be accurately monitored at the receiver side, which is located remotely via the high frequency coaxial line.

In addition, a high-frequency pilot signal is inserted into the input and output ends of the receiving booster amplifier in a time-division manner, and the level fluctuations of the high-frequency pilot signal are compared and detected on the time axis on the receiver side. Gain fluctuations of the receiving booster amplifier can be accurately measured without being affected by output fluctuations of the signal generating means.

Furthermore, by preliminarily measuring the output level of the pilot signal generating circuit or pilot signal generating means, the overall gain from the input end of the receiving booster amplifier to the input end of the receiver can also be monitored.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the invention according to claim 1. FIG. 2 is a diagram illustrating the principle of gain detection of the receiving booster amplifier according to the method of the present invention. FIG. 3 is a block diagram showing the configuration of an embodiment of the invention according to claim 2. FIG. 4 is a block diagram showing a conventional configuration for monitoring the operating state of a receiving booster amplifier. 11... Antenna, 13... Bandpass filter, 1
5... Reception booster amplifier, 17... High frequency coaxial line, 19... Receiver, 21... Pilot signal generation circuit, 23... Time division switch circuit, 25.27...
・Composition circuit, 29... Branching circuit, 31... Pyro・
detection circuit, 33... reference signal oscillator, 35...
Synthesis circuit, 37... Branching circuit, 39... Frequency synthesis circuit, 41.43... Power separation filter (PSF),
45... Power supply circuit, 47... Power supply route, 49...
Current monitor circuit.

Claims (2)

[Claims] (1) A pilot signal generation circuit that generates a high-frequency pilot signal having a different frequency from the high-frequency signal in a reception booster amplifier that amplifies a high-frequency signal received by an antenna and sends it to a receiver connected via a high-frequency coaxial line. , a time division switch circuit that alternately outputs the high frequency pilot signal to two output terminals, and two combiners that insert the high frequency pilot signal taken out to each of the output terminals into the input terminal and output terminal of the reception booster amplifier, respectively. The circuit separates the high-frequency pilot signal from the input terminal of the receiver, detects the level of the obtained high-frequency pilot signal, and calculates the gain of the receiving booster amplifier from the level fluctuation according to the switching timing of the time division switch circuit. A method for monitoring a receiving booster amplifier, comprising pilot detection means for monitoring. (2) In the receiving booster amplifier monitoring method according to claim 1, the receiving booster amplifier side comprises a reference signal insertion means for inserting a reference signal into the high frequency coaxial line on the receiver side instead of the pilot signal generation circuit. A method for monitoring a receiving booster amplifier, characterized in that the method includes pilot signal generating means for detecting a reference signal transmitted through the high frequency coaxial line and generating a predetermined high frequency pilot signal from the obtained reference signal. .