SU756606A1 - Piezoelectric filter of complex phase-manipulated signal - Google Patents

Description

The invention relates to electronics and can be used in devices for processing complex phase maiipulirovannyh signals. d

Piezoelectric filters for processing complex phase-shifted signals are known. They are made on the basis of a multi-branch delay line of surface acoustic waves, containing a sound conductor and transmitting and receiving transducers of surface acoustic waves located on it. [R]. ⁰

The disadvantage of these filters is -. There is a small number of taps and, therefore, limited opportunities for the complexity of the processed signals.

A piezoelectric filter of a complex phase-manipulated signal-20 la is known, containing a suction duct and a transmitting transducer of surface acoustic waves located on it, consisting of η sections located in η parallel 25 acoustic channels shifted relative to each other by. the distance corresponding to the duration of the sampling of the signal, and the receiving transducer of surface acoustic waves, made 30

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1st in the form of a converter matrix of p columns and η rows, where η, p = 1, 2, Zit. e. The pitch of the sections in the columns in this filter is η times the pitch of the sections of the transmitting transducer; the sections of the receiving transducer are electrically connected

among themselves with the possibility of changing the polarity of each of the nr taps from the sections.

The disadvantage of this filter is the small base of the signal being processed. When several such filters are turned on electrically in parallel to increase the base of the signal being processed, distortions of the filter’s electrical characteristics appear, caused by unavoidable technological errors in the manufacture and joining of several partial filters.

The purpose of the invention is to increase the base of the processed signal while maintaining the permissible level of distortion of the electrical characteristics of the piezoelectric filter.

This is achieved by the fact that the piezoelectric filter of a complex phase-manipulated signal, containing 3

756606

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transducer and transducer transducer located on it, surface acoustic waves consisting of η sections located in η parallel * acoustic channels displaced relative to each other by a distance corresponding to the duration of the signal sampling, and a transducer of surface acoustic waves made in matrix form of converters of p columns and η rows, where p, η =

= 1, 2, 3, etc., contains m - 1 additional evukoprovodov with receiving and transmitting transducers of surface acoustic waves located on them, and transmitting transducers contain n - 1 additional sections that are displaced relative to each other in the direction of propagation of surface acoustic waves a distance, η times the offset between the acoustic channels, receiving transducers in each acoustic channel are located with a step of a factor of more than the magnitude of this offset, with sections of each m columns of transmitting transducers on one of m evukoprovodov electrically connected in parallel with the corresponding column sections in the other acoustic lines, and receiving transducers are interconnected electrically in accordance with a predetermined code, where m = 1, 2, 3,. d.

The drawing shows a block diagram of the filter.

The filter consists of individual partial filters. On the surface of each of the piezoelectric t tubes, 1 are located transmitting transducers 2 and receiving transducer 3 of matrix design. Each transmitter transducer 2 consists of η sections located in η parallel acoustic channels and displaced relative to each other in the direction of propagation. an acoustic wave at a distance ϊ _ο , corresponding to the discrete signal duration b, and in the direction of wave propagation, the transducers are shifted by a distance of η · Е _о . Receiving transducers 3 form a matrix of p columns and η rows, with the step between the transducers constituting the columns of the matrix being m-P ′ £ ₀ .

On both sides of each of the columns there are two vertical summing tires 4, combined in turn by two common horizontal summing tires 5 of the filter. The phase of each of the n · p taps is determined by the polarity of connecting the transducer to the vertical summing tires. The input converters of each of the w partial filters are combined in such a way that on each from 30

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A separate sound duct is connected to the common bus 6 only one of those similar transducers, and on different sound ducts; various input converters are combined. Output converters are combined with a common summing bus 7.

The filter of the complex phaeomanipulated signal works as follows.

When the input signal to the transmitting converters in η parallel channels with a shift? determined by the spatial step of the sections of the transmitting transducer, a surface acoustic wave is formed. Reaching the group of transducers of the first column, the acoustic wave forms a partial response of η samples η · C at the output of the combining vertical summing buses 4, the phases of the discretes are determined by the polarity of the connection of the corresponding transducers. Similarly, merge the next columns. The summing response on tires 5 and 7 has a duration T = t · η · p.

The use of a volume-matrix filter design makes it possible to reduce the number of taps in one acoustic channel by a factor of t. This in turn reduces the distortion of the electrical characteristics of the filter caused by the reflections of the signals in the transducers and the parasitic modulation of the impulse response of the filter. In addition, reducing the number of taps in one acoustic channel allows the use of longer piezoelectric evukoprovoda without significant distortion of the electrical characteristics of the filter. This increases the duration of the processed FM signal and, therefore, its base.

The proposed filter allows to process signals with a large base with a rather low level of distortion of the electrical characteristics.

Claims (2)

Claim A piezoelectric filter of a complex phase-shift keyed signal containing a sound pipe and a transmitting transducer of surface acoustic waves located on it, consisting of η sections arranged in η parallel acoustic channels offset from each other by a distance corresponding to the duration of the signal sampling, and a receiving transducer of surface acoustic waves made in the form of a matrix of converters i p columns and η rows, where η = 1, 2, 3, etc., P = 1 ,. 2, Sit.d., characterized in that, with the aim of increasing 756606 6 the base of the signal being processed while maintaining the permissible level of distortion of electrical characteristics, it contains w - 1 additional sound lines with receiving and transmitting transducers of surface acoustic waves located on them, and transmitting converters contain t − 1 additional sections, - offset from each other in the direction of propagation of surface acoustic waves by ^and distance, n times the magnitude of the offset between the acoustic channels, The receiving transducers in each acoustic channel are arranged in increments of n times greater than this displacement, while the sections of each of the ιη columns of transmitting transducers are connected electrically in parallel with the sections of the corresponding column on the other sumps, and the receiving transducers are connected between themselves electrically according to the given code, where w = 1, 2, 3, etc.