V.V. Kiryushkin − Ph.D. (Eng.), Associate Professor, Head of Department, 

JSC SPE «PROTEK» (Voronezh, Russia)

E-mail: kiryushkin.vlad@mail.ru

A.V. Zhuravlev – Dr.Sc. (Eng.), Senior Research Scientist, MainDesigner – Deputy General Director, JSC SPE «PROTEK» (Voronezh, Russia)

E-mail: protek@protek-vrn.ru

S.I. Babusenko − Ph.D.(Eng.), Associate Professor, Leading Research Scientist,

JSC SPE «PROTEK» (Voronezh, Russia)

E-mail: sergbs@mail.ru

A.V. Shuvaev – Leading Engineer, 

JSC SPE «PROTEK» (Voronezh, Russia)

Е-mail: protek@protek-vrn.ru

Target statement. Considering next to non elevel of signals reflected from air targets, one of the critically significant problems for multipositional radar system is the problem of signal-to-noise ratio enhancement. When the transmitter’s power margin is fixed, this problem can be solved by signal storage time prolongation in optimal receiver of pseudorandom sequence over the sequence length extension. Conversely, during hardwear implementation of receiver’s preliminary processing system on programmable logic devices the rearestrict limitations of cells resource necessary for implementation of multichannel matched filters tuned to receive pseudorandom sequence. A compromise can be reached by using a quasi-optimal transmitter with coherent processing of shortlength pseudorandom sequence in a matched filter following exponential digital coherent signal storage. 

Objective. Foundation of a scheme of digital quasi-optimal coherent pseudorandom sequence transmitter based on a matched filter with following exponential digital coherent signals to rage necessary to reach the required signal-to-noise ratio level and definition of signals to rage time necessary to reach the required signal-to-noise ratio level in signal storage device. 

Results. The suggested scheme of digital quasi-optimal coherent pseudorandom sequence transmitter allows to exponentially increase the coherent signal storage time without significant increase of hardware resources. The study showed that the signal storage time should be set so that it provides the equality of the average level of the total cross correlation function lateral peaks and the receiver’s thermal noise. Further signal storage time prolongation is inappropriate as it doesn’t essentially enhance signal-to-noise ratio in the receiver. 

Practical implication. The suggested scheme of digital quasi-optimal coherent pseudorandom sequence transmitter can be used in hardware implementation of preliminary signal processing system in a receiver based on programmable logical devices when register cells resource is strictly limited. 

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