BG65994B1 - Coherent system for signals synchronization by stepwise changes of the carrier frequency - Google Patents

Abstract

The invention relates to a coherent system for monitoring signals by delay with stepwise changes in the carrier frequency, which can find application in the radio engineering systems for connection and control with coherent pseudorandom changes of the operating frequencies. According to the invention, a device has been made for accurate and independent (coherent) reproduction of the phase in the transmitter and the receiver of signals with stepwise changes of the carrier frequency and on this basis û a coherent device for synchronization, serviceable during arbitrary fluctuations of the delay. The frequency synthesizer comprises source of standard (reference) signal (1), primary signal generator (2), switching circuit (3) and frequency divider (4). Generator (2) generates signals with thesame spectral frequency as the source of the reference signals (1) and as a result of the fact that the switching circuit (3) is synchronized with one of the primary signals, the selected signal withthe same phase appears every time when the synthesis is started. In this way the phase of the synthesized signal is controlled and is reproduced independently in transmitter (5) and receiver (8), connected in a circuit for following by delay (6) and delay extrapolator (7).

Description

Technical field

The invention relates to a coherent signal synchronization system with a carrier frequency hopping, which is used in radio communication and control systems with a coherent pseudorandom operating frequency change.

BACKGROUND OF THE INVENTION

Coherent delay monitoring systems are known for radio frequency hoops with frequency hopping comprising two control circuits: frequency and phase, and the presence of a frequency and phase discriminator and smoothing circuits. A signal proportional to the phase difference derivative of the input signal and the tuning generator signal is taken from the input of the frequency discriminator, so the effect of the frequency circuit on the dynamics of the combined system corresponds to the input to the control signal of the mismatch derivative [1, 2] .

The disadvantages of these systems are the need to use a coherent synchronization signal (pilot signal) and their ability to operate only with minimum delay values, ie. if the condition that the delay is much less than the length of the frequency element of the signal with a sudden change in the carrier frequency is fulfilled.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a system for synchronization with accurate and independent (coherent) phase reproduction in the transmitter and receiver with a sudden change in carrier frequency, operable in random fluctuations of the delay.

The problem is solved by creating a frequency synthesizer including a source (standard) signal, a primary signal generator and a switching circuit. The series of primary signals with an angular frequency corresponding to the reference signal is fed to the output of the switching circuit in the form of a phase shifted line. The switching circuit is synchronized with one of the primary signals and the switching can be controlled by selecting the number of cycles of the primary signal.

The advantage of the proposed frequency synthesizer is that the primary signal generator generates them with the same spectral purity as the reference signal source, and because the switching circuit is synchronized with one of the primary signals, the selected signal with the same phase is obtained each time the synthesis, which allows the phase of the synthesized signal to be controlled and reproduced independently in the transmitter and receiver.

Examples of carrying out the invention

An exemplary embodiment of the proposed frequency synthesizer is shown in the accompanying figure 1, representing its block diagram.

According to the invention, the frequency synthesizer consists of a reference signal source

1, primary elementary signal generator

2, in the form of a multivariate delay line with N terminals, switching circuit 3, frequency divider 4, synchronized with one of the simple signals of the generator and connected to the clock input of the switching circuit.

The action of the synthesizer is as follows. The signal from the reference generator 1 with an angular frequency of omega ₀ is fed to the input of the reference signal generator 2 (multivariate delay line with N terminals). The switching circuit 3 is synchronized through the frequency divider 4 and switches after every k cycles of the primary signal. If the time interval between two switches is T, then the phase difference between the synthesized signal and the reference signal increases with phase 0 over time T. Since 0 = 2Πη / Ν, then the synthesized signal can be maintained for arbitrary multiple use times of the N primary signals and the frequency of

65994 The synthesized omega _c signal will be omega _c = omega ₀ + kO / T ₅ . By controlling the switching circuit (selecting k), the phase of the output signal can be changed.

Based on the proposed synthesizer, a system for signal synchronization with coherent hopping of the carrier frequency is obtained, comprising an adjustable transmitter 5, a receiver 8, a delay monitoring circuit 5, a delay extrapolator 7, and a source signal carrier 1, a primary prime generator signals 2, switching circuit 3, frequency divider 4.

The advantage of the proposed system is that, based on the extrapolation of the delay estimation, the moment of synthesis of the desired signal in the receiver correlator is determined to produce the same phase as that used in the transmitter.

An exemplary embodiment of the coherent synchronization system according to the invention is shown in FIG. 2.

The synchronization system comprises an adjustable transmitter 5, a receiver 8, a delay monitoring circuit 6, a delay extrapolator 7 and a reference signal source 1, a primary simple signal generator 2, a switch circuit 3, a frequency divider 4.

The operation of the system is as follows. The standard delay monitoring scheme estimates the current value of the delay. To compensate for the delay, the extrapolator determines the value Tay * (t) and hence the time override, i.e. Tay * (t) = t-Tay (t) of radiation in the transmitter, which is performed by signaling the input of the reference signal generator (multi-delay line).

Claims (1)

Claims CLAIMS 1. Coherent signal synchronization system with hopping carrier comprising an adjustable transmitter (5), a receiver (8), a delay monitoring circuit (6), and a delay extrapolator (7), characterized in that the adjustable transmitter transmitter (5) and receiver (8) include a frequency synthesizer consisting of a reference signal source (1), the output of which is coupled to a simple signal generator (2), made in the form of a multivariate delay line with N terminals, which are connected to a switching circuit (3) such that clock the hundredth multivariate circuit is synchronized with the reference signal period, and the switching circuit (3) is synchronized to one of the elementary signals of the generator (2) by a frequency divider (4) which is connected to the clock input of the switching circuit (3 ), wherein the delay monitoring circuit (6) is connected to the output of the transmitter (5) and to the input of the extrapolator (7), the output of which is connected to the input of the transmitter elementary signal generator (2) (5) . Attachment: 2 figures Literature