SU594593A2 - D-sequence retrieval device - Google Patents

Description

one

The invention relates to radio and can be used in devices whose modulating signal is changed according to the D-sequence law.

From the main. auth. Certificate No. 438130 knows a D-sequence search device containing a search and delay tracking circuit, its input and output are connected to the inputs of a multiplier whose output is connected to the input of another search circuit, and delay tracking.

However, this device has a relatively large search time (synchronization).

The purpose of the invention is to shorten the search.

This is achieved by inserting a series of impulse circuit, counter and switch in the device, the input of the pulse exclusion circuit is connected to the clock output of the first search and delay tracking circuit, and the key output is connected to the clock input of the second search and delay tracking circuit, the output of which is connected to the unitary enterprise) is usl at the key input, and the second

the output of the counter is connected to the second input of the pulse elimination circuit.

The drawing shows a structural electrical circuit of the device.

The B-sequence search device contains the search and tracking circuit 1, the input to the output is connected to the inputs of the multiplier 2, the output of which is connected to the input, another search and delay tracking circuit 3, and successively connected, an impulse exclusion circuit 4, a counter 5 and the key 6, the input of the pulse elimination circuit 4 is connected to the synchronizing 1 output of the search 1 and delay tracking circuit 1, and the output of the key 6 is connected to the synchronizing input of the search 3 and delay tracking, the output of which is connected control input key 6. The second output of the counter 5 is connected to the second input circuit 4 eliminating pulse,

Scheme 1 of searching and tracking the delay of the sosgrhit delay tracking unit 7 and the Generator 8, and the other circuit 3 of searching and tracking the delay contains the block

9 aa delay tracking, reference detection generator 11 11.

The device works as follows.

The reference generator 10 of the search circuit 3 | And the tracking is synchronized by pulses, which in the search mode arrive at the synchronization input of the reference generator of the generator from the output of the key 6 and reset it to the initial state. In this case, the control input of the key 6 does not receive a control pulse from the output of the detection unit 11.

The incoming clock pulses have a period equal to.

k-1

.P

+ 2

tu

;

L

where 2 (J is the period of the input sequence, 2.ff- is the sampling duration

vpornoy VG - sequence. Therefore, from period to period, the reference L / sequence is shifted by the time

L i -.Lrs

paBHoeZj in relation to the P-sequence at the input of the search and tracking circuit 3.

The synchronizing pulses are formed by dividing the frequency of sync pulses from the output of the sync pulse of the generator 8 of the circuit 1 for searching and tracking the reference i-J3 sequence and exclusion.

from the input of the counter 5 of one pulse within the counting time equal to P. to -1

tu n :.

flepno / i- pulses at the input of the pulse exclusion circuit 4 is 2, -, The number of digits of the counter 5 is equal to nk-vl. Poets My pulse period at the output of counter 5 is equal to

k-1

 .

. + 2 ty tu

The search process goes on until the output pulse of the detection unit 11 is detected. The search & tracking circuit 3 & is led to the tracking mode, and the output of the counter 5 is disconnected from the clock input of the reference generator 10 of the reference sequence.

Claims (1)

Invention Formula ZJ search device - sequences by aut. St. No. 438130, which differs from the fact that, in order to reduce the search, serially connected pulse exclusion & are introduced, a counter and a key, with the input of the pulse exclusion circuit connected to the clock output of the first circuit, search and tracking delay, and the key output connected to the synchronizing input of the second search and tracking circuit for the delay, the output of which is connected to the control, the key input, and the second output of the counter is connected to the second input of the pulse suppression circuit.