SU999153A1 - Digital phase detector with sinusoidal characteristic - Google Patents

Description

The invention relates to the field of radio engineering and can be used in digital signal processing systems in radiolocation, radio navigation.

It is known that the phase detector with sinusoidal characterization is the main element of the optimum. phase discriminator.

An analog phase detector with a sinusoidal characteristic is included, which includes an analog input voltage multiplier for the voltage supplied from the output of the harmonic reference voltage generator, and an analog low-pass filter for rejecting side high-frequency components occurring during multiplication 1.

Such a phase detector has low stability and reproducibility, flexibility and versatility, and complexity of interface with computers.

Closest to the invention is a digital detector, which includes a voltage converter, a 1-code, a digital multiplier, and a digital low-pass filter (averaging unit), with the first input.

voltage converter code B is the input of a digital phase detector, converter output is a code - the code is connected to the first input of a digital multiplier, the output of which is connected to the input of a low-pass digital filter (averaging unit), codes are supplied to the second input of the digital multiplier,

10, VL, reference oscillation readings 2.

A disadvantage of the known digital phase detector is a large complexity and low speed,

15 caused by the need to implement the multiplier operation before the filtering operation.

The purpose of the invention is to simplify cxefoi and increase the speed of digital

20 phase detector with sinusoidal characteristic.

This goal is achieved by the fact that a digital phase detector containing a voltage converter is. code,

25 is a digital low-pass filter, the voltage converter input — the code is the input of the digital phase detector, the output of the digital filter is the output of the digital phase

30 detectors, additionally introduced are M stack storage elements, the output of each of which is connected to the input of the same stack Storage element; outputs of the stack storage elements of subsodes (innes to the digital filter inputs with numbers 2,3, ..., M + 1; output of the converter This code is connected to the first digital filter input. In this digital phase detector, there is no unit for multiplying the counting of the input signal by the reference oscillation samples, which is the most complex and determines the speed and magnitudes The drawing shows a block diagram of a digital phase detector with a sinusoidal characteristic. The digital phase detector includes a voltage converter 1 - KQtf, digital filter 2 low frequencies, stack-down elements 3-1}, berth input voltage converter 1 - the code is the input of a digital phase detector, the output of the voltage converter 1 is the code connected to the first input of the digital filter 2, the course of which is the output of the digital phase detector, the outputs are stackable x storage elements 3-1 7 3-M are connected to the inputs of the digital filter 2 with 2.3, 2.3. .., M-t-i, in addition, the output of each stack storage element is connected to the input of the same stack element. Digital Phase1 & The detector with a sinusoidal characteristic works as follows. The signal acting at the input of the digital phase detector of the detector has the form x (-fe) aU) siMCwt 4a)), (1) -de d W - the amplitude of the signal sh - carrier angular frequency; iKi) signal phase. Converter 1 voltage code generates a sequence of samples from the input signal) (1 ()), (2) where T is the sampling interval (period of the clock generator), k is the clock number. The stack memory element is a sequence of N registers. Information is available for reading from this stack memory element, containing only cd in the first register of the stack storage element. For recording information into this stack storage element, only the register of this stack storage element with number N is available. In each stack storage element, the information is transferred from the i-flо register to 1. Before starting a digital phase detector, the registers of the stackable memory elements record the numbers associated with specifying the reference signal and the filter, in the form -. . a4 | a cosCci-J Ou T3, (3) where i -i is the register number of the stack storage element I-1, ..,. J - koMep of the stack recording element J a. - coefficients that determine the type of frequency response of a digital low-pass filter. The clock pulse generator (not shown) synchronizes the operation of converter 1 voltage code, 3-1 t 3-M stackable storage elements and digital filter 2. In each processing step of the input signal, into registers u: front filter 2 of stack storage elements 3-1 3-M, coefficients are transmitted. Digital filter 2 operates in accordance with the equation where bc are the digital filter feedback coefficients that are not changed during the operation of the digital filter, and y are the samples of the output sequence of the digital phase detector. If we denote У., УЦ4ч 5 5) then the samples of the output sequence have vi; e. (6) In view of expression (2), relation (5) is reduced to a form. (7) V4.j4.rO, 6U (() T) siwlvK {-3 ") T)} is a useful component of the signal, containing information about the phase of the signal, ach", bi (C1 -} - ID) 5 -1and |; () l (wT-v4 () T) 11 represents the working high-frequency component of the signal. Digital lowpass filter 2 Passing the component V with the least distortion, suppresses component W to a considerable degree. We assume that d (t) D const and 4 (t) V const, we obtain a sinusoidal dependence of the axial output on fCt). rt -% 4its + e, -, (io) where P - digital filter transmission coefficient at zero frequency; , hSo is the remainder after the rejection of the secondary high-frequency component. Thus, the digital FD detector has a sinusoidal character, which is obtained without the use of a digital audio sensor, the absence of an intermixer increases the speed of the digital phase detector. The formula of the invention A digital phase detector with a sinus rd characteristic V VC-htion converter gigabyte - low-pass filter code, and the input of the voltage converter - code is the input of the digital phase detector, the output of the digital filter is the output of the digital phase detector, with the same , with the aim of adjusting the circuit and increasing the detector's speed, 7 M stacked 3 apomyiaqudia elements are inserted into its composition, the output of which is connected to the input of the same stack, the outputs of the stack of memory elements are connected to the inputs of a 1-filter with ns ceramics 2,3, ..., M + 1, a transistor of the voltage converter - the code pszsdoe inn to the first input of the module. Sources of information taken into consideration by the expert 1.Clean Y.I.I., Sidorov.V.M. I am glad to have a device, M., Svyaz 1974, p. 233. 2. Likharev V.A. Digital methods and devices in the library. M., Soviet rgzdio, 1973, p. 247 (prototype).

xm

JJ JI

9i

Claims (1)

Claim A digital phase detector with a sinusoidal characteristic, containing? 5 in that, for the purpose of "simplifying the circuit and increasing the speed of the detector ^- , M stacked 'memory elements are introduced into its composition, the output of each of which is connected to the input' this is 10 ιό the same stack memory element, you the strokes of the stacked storage elements are connected to the inputs of the digital filter with numbers 2,3, ..., M + 1, the output of the voltage converter is a code connected to the first input of the digital filter.