JPH0371728A - Triple diversity receiver - Google Patents

Abstract

PURPOSE:To reduce a circuit constitution element by providing one band pass filter and an automatic variable gain amplifier on 1st-3rd reception signals, applying phase synchronization and using one synthesizer to synthesize 3 reception signals. CONSTITUTION:The control in phase shifters 4A, 4B is implemented by comparing 1st-3rd intermediate frequency signals subjected to frequency conversion. That is, a part of each intermediate frequency signal is branched and after an undesired wave is filtered by band pass filters 6A-6C, amplified up to a prescribed level by automatic variable gain amplifiers 7A-7C, the phase difference of 1st and 2nd reception signals is detected by a 1st phase difference detector 8A and the difference of 1st and 3rd reception signals is detected by a 2nd phase difference detector 8B. Then the phase shifters 4A, 4B are controlled by 1st and 2nd control sections 9A, 9B based on each phase difference information to execute the in-phase synthesis. Thus, one synthesizer and 3 each of band pass filters and automatic variable gain amplifiers are employed in the receiver.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a microwave radio receiving device, and in particular to a microwave radio receiving device that uses three receiving antennas and synthesizes the receiving power from each of the three receiving antennas.
The present invention relates to a heavy diversity receiving device.

[Conventional technology]

Conventionally, this type of triple diversity receiving device is as follows:
As shown in FIG. 2, the first to third receiving antennas LA
, IB, and IC are frequency converters 3A and 3B using local signals from the local oscillator 2, respectively.

After frequency conversion in 3C, the first received signal and the second received signal are converted to a combiner 5 using a phase shifter 4A.
Synchronous synthesis is performed at A. In addition, 20 Riki Souda and the third
The received signals from the three receiving antennas are synchronously combined in the combiner 5B using the phase shifter 4B, thereby synchronously combining the received signals from the three receiving antennas.

In this case, in phase control in the phase shifter 4A, each of the first and second received signals is passed through the bandpass filters 6A and 6, respectively.
B and automatic variable gain amplifier 7A.

7B, the phase difference between the two is detected by a phase detector 8A, and controlled by a controller 9A. Similarly, phase shifter 5B
In this control, the received signal and the third received signal, which have been combined by the combiner 5A, are passed through bandpass filters 6C, 6D and an automatic variable gain amplifier 7C, respectively.

7D, the phase difference between the two is detected by a phase detector 8B, and controlled by a control section 9B.

[Problem to be solved by the invention]

In the conventional triple diversity receiving apparatus described above, two combiners 5A and 5B are required as a result in order to base the receiving power in two stages. Furthermore, since the phase difference is manually detected in each combiner, four automatic variable gain amplifiers are required to input signals at a constant level to the bandpass filter and the phase detector. Therefore, there are problems in that the number of circuit components increases, the circuit becomes complex, and the receiving device becomes expensive.

An object of the present invention is to provide a triple diversity receiving device in which a combiner and other circuit components are simplified.

[Means to solve the problem]

The triple diversity receiving device of the present invention includes first to third diversity receivers.
first and second phase shifters that respectively control the phase of second and third received signals corresponding to the first received signal among the signals received by the three receiving antennas; and a t-th received signal. and a bottom cover for receiving the phase-controlled second and third reception signals.

Furthermore, first to third bandpass filters that filter a portion of each of the first to third received signals, and first to third automatic variable gain amplifiers that amplify each filtered signal, respectively. and,
A first phase detector detects a phase difference between the amplified first received signal and second received signal, and a second phase detector detects a phase difference between the first received signal and the third received signal. a phase detector, and the first phase detector according to the detected value of the first phase detector.
a first control unit that controls the phase shifter; and a second control unit that controls the second phase shifter in accordance with a detected value of the second phase detector.
It is equipped with a control section.

[Effect]

In this configuration, one bandpass filter and automatic variable gain amplifier are provided for each of the first to third received signals to perform phase synchronization, and one combiner is used to stabilize the three received signals. Therefore, the number of synthesizers, automatic variable gain amplifiers, and bandpass filters can be reduced, resulting in smaller circuits and lower costs.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention.

In the figure, 1. Second. Third three receiving antennas I
The received signals from A, IB, and IC are transmitted to frequency converters 3A, 3B, and 3C by the local oscillator 2, respectively.
is converted to an intermediate frequency band at The second received signal and the third received signal are sent to phase shifters 4A and 4B, respectively.
The phase is changed so that it is in phase with the first received signal, and the synthesizer 5 changes the phase so that it is in phase with the first received signal. Second. Three third received signals are simultaneously bottomed out.

Here, in the phase control in the phase shifters 4A and 4B,
The frequency-converted first . Second. This is done by comparing each third intermediate frequency signal.

That is, a portion of each intermediate frequency signal is branched, unnecessary waves are filtered by bandpass filters 6A, 6B, and 6C, and then amplified to a predetermined level by automatic variable gain amplifiers 7A, 7B, and VC. A first phase detector 8A detects a phase difference between the first and second received signals, and a second phase detector 8B detects a phase difference between the first and third received signals. Then, the first and second control sections 9A and 9B control the phase shifters 4A and 4B based on each phase difference information, thereby performing in-phase synthesis.

Therefore, in this example, the synthesizer can be configured with one piece, and the bandpass filter and the automatic variable gain amplifier can each be configured with three pieces, so that the circuit configuration can be simplified.

〔Effect of the invention〕

As explained above, the present invention provides phase synchronization by providing one bandpass filter and an automatic variable gain amplifier for each of the first to third reception signals, and performs phase synchronization for each of the first to third reception signals. Since the signals are combined, it can be configured with one combiner, three automatic variable gain amplifiers, and a bandpass filter.
Achieve smaller size and lower cost by reducing the number of circuit components.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional triple diversity receiver. IA, IB, IC...first to third receiving antennas,
2... Local oscillator, 3A, 3B, 3C... Frequency converter, 4A, 4B... Phase shifter, 5.5A, 5B...
Combiner, 6A to 6D...Band filter, 7A to 7D...
・Automatic variable gain amplifier, 8A, 8B...phase detector,
9A, 9B...control section.

Claims (1)

[Claims] 1, three receiving antennas, first, second, and third, and three frequency converters connected to these antennas and converting the frequency of each received signal using the same local signal;
first and second phase shifters that respectively control the phase of second and third reception signals in response to the first reception signal; and second and third reception signals whose phases are controlled by the first reception signal. one combiner that combines signals; first to third bandpass filters that filter a portion of each of the first to third received signals; and a first bandpass filter that amplifies each of the filtered signals. a third automatic variable gain amplifier; a first phase detector that detects a phase difference between the amplified first received signal and second received signal;
a second phase detector that detects a phase difference between the first received signal and the third received signal; and a second phase detector that controls the first phase shifter according to a detected value of the first phase detector. 1 control unit;
and a second control section that controls the second phase shifter according to a detection value of the second phase detector.