SU1195272A1 - Apparatus for probability inspection of noise-immune radio receivers - Google Patents

Description

This invention relates to radio measurements and can be used to monitor the noise immunity of radio receivers.

The purpose of the invention is to expand the functionality of the device due to the fact that it is noise-tolerant. The radio receiver under investigation is estimated by the total probability of correct reproduction of the shape of the test signal, with. As a condition for correct reproduction of the instantaneous values of the signal, the inequality is used

(z (t) -s (t + t), jt)

where S (t) and Z (t) - test and. signals played by receiver T - signal delay in the radio receiver under study;

c .. .k is the instantaneous value of the permissible reproduction error caused by the simultaneous action of the specified maximum permissible values of multiplicative jU and additive interference. The drawing shows a functional diagram of the device for the likelihood of monitoring the noise immunity of radio receivers,

The device contains a signal generator 1, the output of which is connected to the input of the delay element 2 and the input of the carrier oscillator 3, the output of which is connected to the first input of the first adder 4, the second input of which is connected to the output of the interference regenerator 5, the output of the adder 4. connected to the input of the studied radio receiver 6, the output of which is connected to the input of the amplifier 7, the output of which is connected to the first signal input of the two-threshold comparator 8, the second signal input of which and the input of the detector 9 is connected to the output of the delay element 2, the output of the detector 9 is connected to the input of the attenuator 10 , the output of which is connected to the first input of the second adder P, the second

the input of which is connected to the output of the potentiometer 12, the output of the second adder 11 is connected to the installation input of a two-port gag. cocharator 8,

the output of which is connected to the first input element And 13, the output of which is connected to the first input of the transmitter. 14 ratios, the second input of which and the second input of the element And 13 is connected to

generator output 15 clock pulses.

The device works in the following way.

Signal S (t) from generator 1 output

the signal performs amplitude-frequency or phase modulation of the carrier oscillator of the generator 3. The received radio signal is summed with the radio interference from the generator 5 of the interference and is fed to the input of the radio receiver 6. The signal reproduced by the radio receiver 6 is transmitted through the amplifier 7. to the first signal input of the two-threshold comparator 8, to the second signal input of which a delayed signal S (t + T) is fed. The two-threshold comparator 8 compares the difference module Z (t) and S (t + t) with the voltage of the permissible error:

V (t) (-1) /. 8a + G) L | „,

where | (Xp |, is the attenuator transfer coefficient 10;. the voltage at the output of the potentiometer .12.

At the output of the two-threshold comparator 8, a signal is generated

1, if / Z (t) -S (t + r). (T);

silt

)

oh, otherwise.

The logical I signal U (t-) opens the access of clock pulses through

ment And 13 at the first input of the calculator 14 of the ratio, on the second, the input of which is continuous, the pulses come from the output of the generator 15. The calculator. 14 of the ratio calculates the number N, and

Pulses passed to its first measurement input T in those time intervals t for which the condition / Z (t) -S (t +.) / Rf | (t) was fulfilled for the correct reproduction of the instantaneous values of the test signal. passed to the second input of the calculator 14 of the ratio during the measurement time T, and the ratio CD / No is calculated, which is the desired value of the total probability of correct reproduction of the shape of the test signal. Indeed, the probability of correct reproduction of the shape the signal is determined by the expression w (S, Z) dsdlz. where A is the region of the correct reproduction of the waveform, given by the inequality / z (t) -s (t + r) (- i) s (t + r) / H- (2) in the two-dimensional space s, z. The two-dimensional density of probabilities is determined by the relation E52lsc§s + 4Sj. L z 4 s w (s, -z) where P, z are specific values of random variables; about where where in t Sla where the prevalence is tat | its Ro is the probability of the simultaneous fulfillment of the conditions indicated in brackets. For stationary ergodic processes S (t) and Z (t), the decrease is 4t | - time intervals during which the conditions are simultaneously fulfilled: S S (t + T): s + 4S (t) z + the duration of the observation interval T. ovitelno P fi (s, z) ıh c / z. And dsdisfiw ds- are time intervals during which a point with coordinates S (t, + T), Z (t) J on the plane S, Z is located inside region A, in other words,. 4C are those points in time when condition (2) is satisfied. The sum is calculated within the range I1 of the measurement interval T. Thus, the device makes it possible to measure the total probability of reproducing the test signal form, which expands the functionality.

Claims (1)

(57) A PROBABILITY CONTROL DEVICE FOR RADIO RECEIVERS, comprising a signal generator, the output of which is connected to the input of the carrier oscillator, the output of which is connected to the first input of the first adder, the second input of which is connected to the output of the interference generator, the radio receiver under study, nuator, characterized in that , in order to expand national capabilities, the output is connected to and with the function — the input element has a delay element, amplifier, two-threshold comparator, detector, second -.... a swarm adder, an And element, a ratio calculator and a clock pulse generator, the output of the radio receiver being studied by the signal input of the parator, the second signal input of which is connected to the output of the delay element, the input of which is connected to the output of the signal generator, and the input of the detector, the output of which is connected to the input of the attenuator whose output is connected to the first input of the second adder, the second input of which is connected to the output of the potentiometer, and the output to the installation input of a two-threshold comparator, the output of which is connected to the first input element. And, the output of which is connected to the first input of the ratio calculator, the second input of which is connected to the output of the clock pulse generator and the second input of the element I.