SU813702A2 - Digital band-pass filter - Google Patents

Description

one

The invention relates to radio engineering and can be used to filter the measurement results of a physical parameter expressed by a digital code.

According to the main author. St. No. 499647 is a non-linear digital filter comprising a series-connected comparison unit, a two-sided limiter, an adder, and a non-recursive filter, the output of which is connected to the additional inputs of the adder and comparison unit fl.

A disadvantage of this device is the relatively low filtering accuracy with variable measurement accuracy and the presence of bursts of abnormal intent errors.

The purpose of the invention is to increase the accuracy of filtration.

For this, in a non-linear digital filter containing a series-connected comparison unit, a two-sided limiter, an adder and a non-recursive filter, the output of which is connected to

Additional inputs of the adder and comparison unit, between the output of the double-sided limiter and the additional input of the accumulator are connected in series to the quad, additional non-recursive filter and random number sensor, the other input of which is connected to the additional output of the double-sided limiter, the additional non-recursive filter is connected to the additional input of

The drawing shows a structural electrical circuit of a non-linear digital filter.

It contains a series-connected comparison block 1, a two-sided limiter 2, an adder 3, and a non-recursive filter 4, the output of which is connected to other inputs of the comparison block 1 and the adder 3, as well as a series-connected quad 5, an additional non-recursive filter 6 into the random number generator 7, output This is connected to the second additional input of the adder 3, and the input of the quarantor 5 is connected to the full output of the bilateral limiter 2, and the output of the additional non-recursive filter 6 to the additional the input of the two-sided limiter 2, the auxiliary output of which is connected to the input of the random number sensor 7. The non-linear digital filter works as follows. In the steady state mode, in the absence of anomalous distortions and constant measurement accuracy, the measurement results through the comparator unit 1, the two-way limiter 2 and the adder 3 are fed to the non-recursive filter 4, which works as a normal averager. At the same time, negative feedback from the non-recursive filter 4 to the comparison unit 1 is compensated by positive feedback from the non-recursive filter 4 to the adder 3. In this case, at the output of the non-recursive filter 4, we have a sliding interval estimate of the value of the measured parameter by the result of a certain number measurements. At the same time, however, the signal from the additional output of the two-way limiter 2 is supplied to the input of quadrant 5, in which the measurement results are squared. The signal from the output of the quadrant 5 enters an additional non-recursive filter 6, the output of which has a short interval estimate of the dispersion of measurements, which is fed to the additional input of the two-way limiter 2 and to the input of the random number sensor 7. When measuring the value of the dispersion of measurements, i.e., when measuring the measurement accuracy, the threshold values of the limits of the gel 2 are adjusted in accordance with the signal supplied to its auxiliary input from the output of the additional non-recursive filter G. Thus, the adaptation Respect for variable precision measurement that leads to improved filtering accuracy. At the same time, if the result of measurements with an anomalous error arrives at the filter input, then in double-sided limiter 2, the input signal of the upper or lower threshold of limiter 2 is exceeded. In this case, the second additional output of limiter 2 random number sensor 7, which launches this sensor. The signal from the output of the latter is fed to the input of the adder 3. Thus, the abnormal error is replaced by a signal from the random number sensor and, since the signal from the additional non-recursive filter 6 is received at the input of the sensor 7, the statistical characteristics of the signal at the output of the sensor 7 coincide with the statistical characteristics measurement results. In this case, the corresponding US-to-vice in the measurement result with an anomalous error does not come to the input of the adder 3 from the two-sided limiter 2. As a result, when filtering subsequent measurements on the results of interval estimates, anomalous errors will not be reported. The formula is found Nonlinear digital filter auth.St. No. 499647, characterized in that, in order to improve the accuracy of the fraction, between the output of the other-sided limiter and the cumulative input of the dispenser are included a quadrant additional non-recursive filter and a random number sensor connected to an additional input connected to the additional output of the two-sided limiter, the additional input of which is connected non-recursive filter. Sources of information taken into account during the examination 1. USSR author's certificate No. 499647, cl. And OZ N 7/28, 1972 (prototype).

Claims (1)

Claim Nonlinear digital filter by auto Ν "499647, characterized in that, in order to increase the filtering accuracy, a quadrator ', an additional non-recursive filter and a random number sensor, the other input of which is connected to the additional output of the two-way limiter, to the additional input of which are connected between the output of the two-way limiter and the additional input of the adder the output of an additional non-recursive filter is connected.