SU921108A2 - Device for synchronizing noise-like signals - Google Patents

Description

(54) DEVICE FOR SYNCHRONIZATION OF NOISE-LIKE

SIGNALS

one

The invention relates to radio engineering and can be used in communication systems with noise-like signals requiring accelerated synchronization.

According to the main author. St. No. 576669, a device for synchronizing noise-like signals is known, which contains multipliers connected to the first input, to the second inputs of which are connected the outputs of the carrier frequency generator, and the outputs of the multipliers through the serially connected top modules of the signals and integrators are connected to the inputs of the first and second adders, the outputs of which are connected to the inputs of the third adder, the output of which is connected through the serially connected converter and the threshold unit to the input of the control unit, the output to This is connected to one of the inputs of the modulator of signals and the second input of the threshold unit 1.

However, the known device has a long time for the coaxing of noise-like signals due to the fact that there is no assessment of the state of the communication channel.

The purpose of the invention is to reduce the search time for noise-like signals.

The goal is achieved by the fact that a noise-like signal synchronization device containing multipliers integrated at the first input, to the second inputs of which are connected the outputs of a carrier frequency generator, and multipliers that connect through serially connected signal modulators and integrators are connected to the inputs of the first and second adders, the outputs of which through the quadrants are connected to the inputs of the third adder, the output of which is connected through a series-connected converter and a threshold unit to

15 the input of the control unit, the output of which is connected to one of the inputs of the modulator of signals and the second input of the threshold block, is entered in series with a key element, analog-code converter, shift register, addition unit, element

20 memories, a divider and a deflator, while the outputs of the third adder and threshold unit are connected to the inputs of the key element, and connected to the second and third inputs of the adder unit

the second output of the memory element and the output of the analog-code converter.

The drawing shows a block diagram of the device.

The synchronization device for noise-like signals contains multipliers 1 and 2, carrier frequency generator 3, quadrants 4 and 5, third adder 6, converter 7, threshold unit 8, modulator 9 signals, integrators W and 11, first and second adders 12 and 13, unit 14 control, key element 15, converter 16 — analogue code, shift register 17, addition unit 18, memory element 19, divider 20, decoder 21.

The device works as follows.

The signal and interference mixture input to the device (or only the noise in the search mode multiplies in multipliers 1 and 2 with the carrier voltage and with the voltage shifted in phase by JI / 2 received from the carrier frequency generator 3. Signal from the multipliers 1 and 2 are manipulated in the modulator of 9 signals according to the law of pseudo-random sequences (SRP), displaced among themselves by the length of the SRP element (or more in the case of searching for sequences in the temporal uncertainty zone), and the resulting convolution of the signal is integrated integrators 10 and 11. The integration result in integrators 10 and 11 are combined into one channel by the first 12 and second 13 adders, respectively, to form a sequence of values, the direct and quadrature components of the correlation function. The values obtained are squared by quadrs 4 and 5 and are summed in pairs by the third adder 6, the square root in converter 7 is extracted from them and the results are compared with the adjustable threshold of the threshold unit 8. When the threshold is exceeded, the signal from the control unit 14 controls the threshold in the pores govom unit 8, as well as modulating CAP modulator 9 signals. The control unit 14 determines the operation modes of the synchronization device, i.e. search mode and tracking mode for the SRP signal.

In the PSP search mode, the analog values of the quadrature mutual correlation function (KBK.F) interference and signal copies obtained in the third adder 6 are transmitted through the open key element 15 to the analog-code converter 16, where they are digitized. The signals from the analog-code converter 16 are digitally fed to the shift register 17 and to the second input of the addition unit 18. In block 18 of addition, on each clock cycle, the current value KB KF with the number written in memory element 19 is added, and the previously obtained value KB KF is subtracted, I enter

from the output of the register 17 shift. The result of this summing is rewritten in the memory element 19. The divider 20 normalizes the root-mean-square value of the responses of the integrators 10 and 11 by dividing the number of the summation accumulated in the memory element 19 by the number n and the number n of the processed responses KB KB and the number of bits shift register 17 n / 2 is determined by the required accuracy of the evaluation of the quality of the state of the communication channel and is limited by the specified promptness of obtaining the estimate. Averaged over the interval Tk ToP where n is the length of the element of the SRP signal arrives at the decipheror 21, which is a multi-level threshold device and the deciding unit. When the Kth level is exceeded by a threshold value set in the decoder 21 by a signal from the output of divider 20, an estimate of the state of the binary channel is formed in the form of the probability of the ROCK error in the reception of a single element. The search stage ends with the output of a signal from the threshold block 8; by KorofWiMy, the control block 14 changes, in part., The sequence frequency in

5 modulator 9 signals, which is monitoring the parameters of the SRP. At the same time the signal from the threshold unit 8 closes the key element 15.

Thus, the use of this device allows to reduce the search time for a noise-like signal, evaluate the quality of the channel at the poker stage, and if the communication system provides for control over the monitoring results, then you should refuse this channel and switch to the backup channel if it does not satisfy quality requirement, i.e. ROCK Rotre6. Formula of the invention

0 Synchronous signal synchronization device for auth. St. No. 576669, characterized in that, in order to reduce the search time for noise-like signals, key connected in series are introduced

5 element, analog-code converter, shift register, addition block, memory element, divider and decoder, while the outputs of the third adder and threshold block are connected to the inputs of the key element, and the second output of the memory element are connected to the second and third inputs of the addition block TI and the output of the converter analog-code.

Sources of information taken into account in the examination 1. USSR author's certificate № 576669, cl. H 04 L 7/04, 1975 (prototype).

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Claims (1)

Claim Synchronization device noise-like signals auth. St. No. 576669, characterized in that, in order to reduce the search time for noise-like signals, a serially connected key element, an analog-code converter, a shift register, an addition unit, a memory element, a divider and a decoder are entered, while the outputs of the third adder and threshold unit are connected to the inputs of the key element, and the second output of the memory element and the analogue code converter output are connected to the second and third inputs of the addition unit, respectively.