JPH01106614A - Multiplier - Google Patents

Abstract

PURPOSE:To simplify the adjustment and circuit constitution by adjusting the level of a high frequency signal path depending on the level adjustment of a base band signal. CONSTITUTION:A high frequency signal decomposed into the real component and the imaginary component by a pi/2 demultiplexer 1 is given respectively to 0-pi linear phase shifters 2, 3, and the real component and the imaginary component of a base band signal from pots 11, 12 are given respectively to the phase shifters 2, 3 via interfaces 7, 8 and variable amplifiers 20, 30. The phase shifter 2, 3 multiplies the respective input and gives the result to a multiplexer 6. Each gain of the amplifiers 20, 30 is set so that a desired waveform is obtained from a port 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multiplier used in non-line-of-sight communication systems and the like.

[Conventional technology]

In non-line-of-sight communication systems, maximum ratio combining of Guivasity and adaptive matched filters (Adaptive Matched Filter) are used.
alter) and decision feedback equalizer (Deci-sion
Feedback Evaluator) is adopted, and a multiplier is used in it.

, FIG. 2 is a pull diagram of a conventional multiplier of this type. The input signal from the high-frequency signal input port 9 is separated into a real component and an imaginary component having a difference of π/2 by a π/2 splitter 1, and is applied to O-π linear phase shifters 2 and 3, respectively. On the other hand, the signals of the real component and imaginary component of the baseband signal are also transmitted from the real port 11 and the imaginary port 12 to the interface circuits 7 and 8, respectively.
(performs voltage shift, etc.) through O-π linear phaser 2
and 3. The above-mentioned two forces applied to the 0-π linear phase shifters 2 and 3 are multiplied and sent to the attenuators 4 and 5, respectively.

The 0-π linear phase shifters 2 and 3 output a signal whose output level changes linearly with respect to the amplitude of the baseband signal, and whose output phase changes by O-π according to the polarity of the baseband signal. For example, the attenuators 4 and 5, which can be configured with a ring modulator or the like, attenuate the input signal so as to eliminate the level difference between the real component and imaginary component paths, and provide it to the multiplexer 6. The multiplied equal-level real components and imaginary components applied to the multiplexer 6 are multiplexed and output from the signal output port 10.

[Problem that the invention seeks to solve]

In the conventional multiplier described above, an attenuator is inserted in the high frequency signal path after multiplication to adjust the level.
Adjustment is difficult and the circuit is complicated.

An object of the present invention is to provide a multiplier with easy level adjustment and a simple circuit configuration.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention provides a branching filter that branches high-frequency signals into two signals having a phase difference of π/2 (or the same phase), and each branched signal of the branching filter. first and second phase shifters that multiply the output of the baseband signal by the real component and the imaginary component of the baseband signal, respectively; In the multiplier equipped with a multiplexer that performs multiplexing (by giving a phase difference), there is obtained a multiplier characterized in that it includes means for varying the gain of at least one of the real component and the imaginary component of the baseband signal.

〔Example〕

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

FIG. 1 is a block diagram of an embodiment of the invention. As in the conventional example, the high frequency signals separated into real components and imaginary components by the π/2 splitter 1 are applied to 0-π linear phase shifters 2 and 3, respectively. On the other hand, the real component and imaginary component of the baseband signals from the real port 11 and the imaginary port 12 pass through interface circuits 7 and 8, respectively, and are amplified by variable amplifiers 20 and 30, and are amplified by O-π linear phase shifter 2 and given to 3. o
The -π linear phase shifters 2 and 3 multiply the above-mentioned two-power inputs and supply the multiplication results to the multiplexer 6. The multiplexer 6 is 2
The human power is combined and a combined signal is output to the output port 10.

Here, the gains of the variable amplifiers 20 and 30 are set so that a desired waveform can be obtained from the signal output port 10.

Note that instead of the π/2 demultiplexer 1 and the multiplexer 6, a demultiplexer that branches into two signals in the same phase and a multiplexer that multiplexes the signals with a phase difference of π/2 may be used.

〔Effect of the invention〕

As explained above, according to the present invention, the level adjustment of the high frequency signal path is performed by the level adjustment of the baseband signal, which facilitates the adjustment and also simplifies the circuit configuration.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example. 1...π/2 splitter, 2, 3...Q-
π linear phase shifter, 4, 5... Attenuator, 6...
...Multiplexer, 7゜8...Interface circuit, 9...High frequency signal input port, 10...
...Signal output port, 20°30...Variable amplifier. Agent Patent Attorney Susumu Uchihara

Claims (1)

[Claims] A splitter that splits high-frequency signals into two signals having a phase difference of π/2 (or the same phase), and the split outputs of this splitter and the real and imaginary components of the baseband signal. the first and second to multiply respectively
and a multiplexer that combines the outputs of the first and second phase shifters in the same phase (or with a phase difference of π/2), in which the base A multiplier comprising means for varying the gain of at least one of a real component and an imaginary component of a band signal.