SU614517A1 - Pseudorandom signal generator - Google Patents

Description

(54) GENERATOR OF PSEUDICAL SIGNALS

one

The invention relates to radio engineering and can be used in rvdioepektronnyh devices, in particular, in the simulators of the Doppler signals necessary for the combination of the Doppler velocity meters of aircraft.

Lime pseudorandom generator; containing the source of a pseudo-random sequence of pulses, the generator of synchronizing signals shuffy; frequencies whose outputs: are connected to the corresponding penfCTpia shift shells, as well as series-connected ne | the first multichannel multiplier, the first adder, the inverter adder into the low-pass filter; Llj ..

However, such a pseudo-random signal generator has insufficient accuracy in setting the average frequency of the output signal.

The aim of the invention is to improve the accuracy of setting the average frequency of the gate. signal.

g To do this, a pseudo-random signal generator containing a source of a pseudo-random pulse sequence, a generator of variable frequency synchronizing signals, whose outputs are connected to

1 by the corresponding inputs of the shift register, as well as sequentially connected the first multi-channel multiplier, the first adder daiertor, the second adder n

- a low-pass filter, while you do the odd bits of the shift register are connected to the inputs of the first multichannel multiplier, and the outputs of the even bits through the second multicash multiplier to the other inputs of the second adder, having entered

20 cosmic impulse generator (Jcos), interposed between the output of the variable frequency clock signal generator and the reference inputs of the first n second multichannel multiplier & 23 multipliers.

The drawing shows a structural electrical circuit of the proposed pseudo-random signal generator.

The pseudo-random signal generator contains a source of 1 pseudo-random pulse train, a generator of 2 variable frequency clock signals, the outputs of which are connected to the corresponding inputs of the shift register 3, as well as the first multi-channel multiplier 4, the first adder 5, the inverter 6, the second adder 7 and the filter . 8 low frequencies, while the outputs of the odd bits of the Eigod 3 shift are connected to the inputs of the first multichannel multiplier 4, and the outputs of the bits through the second multichannel multiplier 9 with the other inputs of the second adder 7, entered by the cosmicator of the cosine pulse IcosiftJ ij between the output of the generator 2 synchronizing signals of variable frequency and the reference inputs of the first and second multichannel multipliers 4 and 9.

The pseudo-random signal generator works as follows.

From source 1, a pseudo-random sequence of pulses is fed to the input of shift register 13, and its instantaneous values (O and 1) are written to the first bit of shift register 3 with step T defined by shift pulses entering shift register 3 from generator 2. C is even the outputs of the shift register 3 pseudo-random pulse signals X С t - Ш Т), shifted in time with step 2Т, are fed to the first multichannel multiplier 4, in which they are multiplied by the signal | PO2 ООЬЬ and the corresponding discretized values of the bend impulse characteristic H (-t) -e 7

from the even-bit register outputs, 3 shifts, the pseudo-random pulse signals X (4: -111Т)., shifted in time with 2T, are fed to the second multichannel multiplier 9, in which they are multiplied by the JCOS signal. to the corresponding sampled values of the impulse response

H (t) at 4,6.

with the outputs of the first and second multichannel multipliers 4 and. 9, the signal of the form X (i-mT) xe is fed to the inputs of the first and second adders 5 and 7, respectively. Signal from the output of the first

adder 5 is fed to inverter b, from which the adder signal, multiplied by -1, is fed to the input of the second buzzer 7. As a result of summing the signals on the second adder 7, a narrow-band pseudo-random signal is allocated to its input

(t-mT). (i) t | x

tj-1 for even ig and W 0 0} -1 for odd m,

where "1 is the number of the digit, and nt | - the number of bits in register 3 shift.

The set of operations performed in the proposed device implements the functions of convolution of the input signal according to a given impulse response, close to the impulse response of a Gaussian filter.

The proposed pseudo-random signal generator provides a smooth overlap of the working frequency range and a high accuracy of setting the center frequency by eliminating the influence of low-pass filters on it.

Claims (1)

1. U.S. Patent K 3,731,309. Q. 01 S 7/40, 1973.