Formation and reception of signals of a high-speed wireless data transmission system of short range in an urban area against the background of interference

Formulation of the problem: the use of high-speed short-range wireless data transmission systems in an urban area imposes immunity requirements on these systems with respect to small-scale fading arising from multipath propagation of radio waves in an urban area, besides it is used requirements for immunity against in-band interference arising from the simultaneous operation of these systems in the same frequency range at a small distance from each other. Along with these requirements, a short range system must meet the growing requirements for spectral and power efficiency, which leads to restrictions on the occupied frequency bandwidth and signal crest factor.

Purpose: to develop recommendations for the formation and reception of signals for high-speed short-range wireless data transmission systems operating in an urban area against the background of additive in-band interference, taking into account restrictions on the occupied frequency band and signal crest factor.

Results: a signal structure is defined for use in short-range data transmission systems, taking into account the imposed restrictions. Existing methods for receiving a selected signal structure under conditions of simultaneous exposure to small-scale fading and additive in-band interference are considered. A practical acceptance algorithm based on the considered methods has been developed. It is proposed to use four-position phase modulation with the maximum possible expansion of the spectrum when forming a signal. The recommended reception algorithm includes matched filtering combined with in-band interference suppression using the proposed additive in-band interference suppression algorithm, and inter-symbol distortion correction with primary symbol synchronization using a fractional interval equalizer.

Practical significance: these recommendations make it possible in practice to develop signal-code structures and methods for their reception for digital radio communication systems operating in a complex signal-interference environment while ensuring their spectral and energy efficiency. The reliability of the results was confirmed by mathematical modeling.