N.A. Vorobev1, V.I. Djigan2, P.V. Luferchik3, P.V. Shtro4

1,3,4 JSC «SPE «Radiosvyaz» (Krasnoyarsk, Russia)

2 National Research University «MIET» (Moscow, Russia)

1 vorobev_na@krtz.su, 2 djigan@org.miet.ru, 3 lpv@krtz.su, 4 shtro_pv@krtz.su

It is known that intersymbol interference appears due to the multipath propagation of the radio signal when data are transmitted through a tropospheric radio channel. The interference can lead to a significant distortion in the quality of received information. To reduce this phenomenon, the adaptive equalizers are often used in the receiver. An equalizer is used to equalize the amplitude-frequency characteristics of the communication channel. There are different structures of the adaptive equalizer, so there is a problem of the most effective equalizer structure selection for use in tropospheric radio communication systems.

A software platform has been developed for the investigation and the prototyping of the adaptive equalizers. It also includes the main elements of the communication system equipment. The simulation of the various equalizer structures under the conditions of a specific tropospheric channel (the number of the impulse response rays is 4, the maximal delay between the rays is 530 ns, the fast fading frequency is 15 Hz) demonstrates that the best results in terms of the equalized amplitude-frequency response ripple (±0,5 dB) under these conditions provides an equalizer with a fractional delay and feedback based on a Recursive Least Squares algorithm.

The selection of the most effective adaptive equalizer allows to increase the efficiency of the tropospheric radio communication system, which in turn increases its throughput and operation distance. The developed software platform can be used to determine the optimal structure of the adaptive equalizer, the number of its weights and the algorithm for the weights calculation for the usage in the specified operational conditions of a communication system.

Vorobev N.A., Djigan V.I., Luferchik P.V., Shtro P.V. Estimation of the effectiveness of using adaptive equalizers with different structures in troposcatter communication systems. Achievements of modern radioelectronics. 2023. V. 77. № 12. P. 114–123. DOI: https://doi.org/10.18127/j20700784-202312-14 [in Russian]

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