SU1058078A1 - Receiving device of communication system - Google Patents

Abstract

RECEPTION DEVICE OF THE COMMUNICATION SYSTEM, containing a series-connected high-frequency amplifier, a mixer, the second input of which is connected to the output of a local oscillator, a band-pass filter, a limiter, a frequency discriminator, a low-pass filter and a decisive unit, characterized in that, in order to improve noise immunity, an amplifier is introduced the first and second filtering units, the first and second Doppler frequency meters and the computing unit, while the output of the amplifier, whose input is connected to the output of the ground filter, is connected to the input Odam first and second filtering blocks, the outputs of which are connected to the inputs of the first and, respectively. of the second measuring Doppler frequency, whose outputs are connected to the first and second inputs of the computational block, respectively, whose output is connected to the second input (L of the frequency discriminator. SP 00 O s X)

Description

This invention relates to technical assistance and is intended to receive information and. measuring the speed of relative movement of the transmitter and receiver on the information signal,

A known receiver of signals with modulation, containing an input device, a converter, a frequency discriminator, a low-pass filter, and an indicator block l | .

However, the known receiver does not have the ability to measure the speed of relative movement.

The closest in technical terms to the present invention is a receiving device of a communication system comprising a series-connected high-frequency amplifier, a mixer, the second input of which is connected to the output of a local oscillator, a band-pass filter, a limiter, a frequency discriminator, a low-pass filter and a decider unit 2} . .

A disadvantage of the known device is low noise immunity.

The purpose of the invention is to improve the 1P9 resistance.

To achieve this goal, the receiver of the communication system, containing a series-connected high-frequency amplifier, a mixer, the second input of which is connected to the output of the local oscillator, a band-pass filter, a limiter, a frequency discriminator, a low-pass filter and a decisive block, is inserted into the amplifier, the first and second blocks filtering, the first and second Doppler frequency meters and the computing unit, while the output of the amplifier, whose input is connected to the output of a bandpass filter, is connected to the inputs of the first and second blocks phi Ltrtions whose outputs are connected to the inputs of the first and second Doppler frequency meters, respectively, the outputs of which are connected respectively to the first and second inputs of the computing unit, the output of which is connected to the second input of the frequency discriminator.

The drawing shows a block diagram of the device.

The device contains a high-frequency amplifier 1, a mixer 2, a band-pass filter 3, a limiter 4, a frequency discriminator 5, a low-pass filter 6, a decision block 7, a local oscillator 8 ,. amplifier 9, first filtering unit 10, first Doppler frequency meter 11, computing unit 12, second filtering unit 13, second meter Doppler frequency meter 14.

The receiver of the communication system operates as follows.

At the input of the high-frequency amplifier 1, a radio signal is supplied with a pulse-frequency-frequency modulation (KHMj-4M), the duration of which pulses coincide with their period

1 corresponding,

 the symbol, frequency i, and

symbol - frequency i-f (). In this case, it is assumed that i is where 4 DL is the pulse signal intensity of the signal, i.e. in practice, radio pulses corresponding to the symbols i and -1 are orthogonal.

The pulse amplitudes of the information sequence are independent

 11 I

and -1

15 and take the value

with a probability of 0.5. The information sequence can be represented as the sum of two sequences: the first, the pulses of which take the value O

I J I I 1 I

when the pulses of the initial information sequence are equal, O in the remaining cases, and the second one, the symbols of which take the values

and -1 - -I

when the pulses of the original information sequence are equal, O in the remaining cases.

Radio pulse sequences corresponding to the first and second sequences can be considered independently due to the practical orthogonality of the radio pulses.

one

matching characters

and -1 source sequence, ty.

from the output of the local oscillator 8 to the second input of the mixer 2, a harmonic signal of frequency i g is supplied. from output 0 of mixer 2, a signal whose symbol corresponds to a radio pulse with a frequency of

) -ire.,

and the symbol is a radio pulse with a frequency of

,

where V is the speed of relative movement of the transmitter and the proposed receiver (positive when approaching); C is the speed of light

is fed to the input of the bandpass filter 3 ,. the bandwidth of which is chosen based on a priori information about the maximum speed value and

- (. Wmax

L) -. amounts to 1D-het.

f,

before

From I,

where the module is the value of the maximum speed of the relative movement of the transmitter and the proposed method -. device.

Claims (1)

SYSTEM RECEIVER (COMMUNICATION, comprising a high-frequency amplifier connected in series, a mixer, the second input of which is connected to the local oscillator output, a bandpass filter, a limiter, a frequency discriminator, a low-pass filter and a resolving unit, characterized in that, in order to increase the noise immunity, an amplifier is introduced ., the first and second filtering units, the first and second Doppler frequency meters and the computational unit, while the output of the amplifier, the input of which is connected to the »» output of the gloss filter, is connected to the inputs the first and second filtering units, the outputs of which are connected to the inputs of the first and second measuring Doppler frequencies, respectively, the outputs of which are connected respectively to the first and second inputs of the computing unit, the output of which is connected to the second input of the frequency discriminator. SU. ,,, 1058078