SU834854A1 - Device for shaping shifted copies of pseudorandom signal - Google Patents

Description

(54) DEVICE FOR THE FORMATION OF SLIPPED COPIES OF A PSEUDOM SIGNAL

I

The invention relates to a pulse technique and can be used to search for a pseudo-random phase-shift keyed signal, as well as to simulate random processes.

A device for generating shifted copies of a pseudo-random signal is known, comprising a M-sequence generator, decoders, modulo-two adders, memory blocks and a clock pulse generator 1.

A disadvantage of the known device is that the shifted copies of the segments of M-sequences contain many elements that are different from the recurrent rule of the formation of a sequence, which ultimately leads to a decrease in the reliability of the device.

The purpose of the invention is to increase the reliability of the device.

This goal is achieved in that a device for generating shifted copies of a pseudo-random signal, comprising a clock generator, the output of which is connected to the clock input of the M-sequence generator; pulse counter, decoders and modulo-two adders, an additional M-sequence generator, two shift registers, switching blocks and a reset pulse distributor, the first and second outputs of which are connected via the M-sequence generators to the first and second inputs of the first switching block, and to the first inputs of the first and second shift registers, the bit outputs of which are connected through the corresponding modulo two adders to the first and second inputs of the (n-1) switching blocks, respectively, control The main inputs of which are connected via decoders to the bit outputs of the pulse counter, the output of which is connected to the control inputs of the first switching unit and the reset pulse distributor, and the output of the clock generator of the additional M-sequence, shift registers and pulse counter.

The drawing shows the functional diagram of the device.

The device contains generators 1 - and 2 M-sequences, a distributor of 3 reset pulses, adders 4 modulo two, switching units 5, decoders 6, a counter of 7 pulses, registers 8 and 9, a generator of 10 clocks. Switching unit 5 is made on a trigger, the outputs of which through the corresponding elements AND are connected to the inputs of the OR element, the output of which is the output of switching unit 5, and the second inputs of the AND elements and the counting input of the trigger are inputs of switching unit 5 (execution of block 5 is not shown) .

The device works as follows.

The input of the counter 7 receives clock pulses from the generator 10. The division factor of the counter 7 is equal to the number of elements in the M-sequence segment, resulting in the output of the counter 7 forming a sequence of pulses with a period equal to the duration of the M-sequence segment. Through the distributor 3 of the reset pulses, the even pulses of this sequence are reset to the initial state of the 1 M-sequence generator, and the odd pulses are the generator of the 2 M-sequence. These sequences are fed to the inputs of the first switching unit 5, to the control input of which pulses are fed from the output of counter 7. With the arrival of an odd pulse, this switching unit 5 passes a sequence to the output for a time equal to the specified duration of the M-sequence. After that, the next (even) pulse from counter 7 comes to the control input of the first switching unit 5, and the first unit 5 starts to pass a sequence to the output.

Thus, at the output of the first switching unit 5, a sequence is formed consisting of identical segments of M-sequences.

Sequences from generators 1 and 2 are sent to shift registers 8 and 9, which serve to get the required number of sequences shifted per clock relative to each other from the outputs of generators 1 and 2. From the outputs of the E-shift registers, two inputs are given to the inputs of modulators 4 similar to the sequences from the outputs of the generators I and 2. At the outputs of the adders 4 modulo two, sequences are shifted relative to the sequences at the outputs of the generators 1 and 2, with the shift order is determined by the law of connecting the inputs of adders 4 to registers 8 and 9. From the outputs of adders 4 modulo two shifted sequences are fed to the inputs (p-1) of switching blocks 5, to the control inputs of which are shifted relative to the pulses sequences of counter 7, and the shift value is equal to the shift of the sequences arriving at the same switching unit 5. All blocks 5 work similarly to the first block 5. During the operation of the odd period of the pulse sequence of the counter 7, the signal from the one group of adders 4 is passed to the output, during the even period from the other group of adders 4. As a result, the outputs of the switching blocks 5 form a sequence which is shifted in time relative to the sequential sequence at the output of the first switching unit 5, "it does not contain elements that do not comply with the recurrent rule of formation of the M-sequence. Blocks 5 operate similarly to the first switching unit 5 and are inserted into the device in order to simultaneously receive several copies of a sequence with different shift values.

Claims (1)

Invention Formula A device for generating shifted pseudo-random signal copies, comprising a clock pulse generator, the output of which is connected to a clock input of an M-sequence generator, a pulse counter, decipherors and modulo-two adders, characterized in that entered the M-sequence generator, two registers, shift, switching blocks and the distributor of reset pulses, the first and second outputs of which are connected respectively via the M-terminal generators the first and second inputs of the first switching unit and the first inputs of the first and second shift registers, the bit outputs of which are connected through the corresponding modulo-two adders to the first and second inputs (p-1) of the switching units, respectively, the control inputs of which are connected through delimiters to the bit outputs of the pulse counter, the output of which is connected to the control inputs of the first switching unit and the distributor of the pulse pulses, the output of the clock generator being connected to the clock inputs additional generator of M-sequence, shift registers and pulse counter. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 527012, cl. H 03 K 3/00, 1976.