Antenna Diversity of Wi-Fi Signals Using a Switched Antenna Array

Relevance. The active use of wireless technologies requires the development of controls for wireless networks, in particular Wi-Fi networks. Radio monitoring services solve the tasks of detecting, identifying and localizing unauthorized access points and clients. An effective tool for bearing radio signals is correlation interferometric direction finders based on two-channel receiving equipment and a multi-element antenna system. The development of methods of joint identification and bearing makes it possible to separate the bearings of a large number of signal sources operating in the same frequency range with time division. In this work, the emphasis is placed on the detection of target signals and the identification of source features from them. The indicators of the quality of bearing will also significantly depend on the success of these operations. The aim of the work is to investigate the possibilities of increasing the interference resistance of detecting and identifying Wi-Fi signals through the combined use of two channels of a correlation interferometric detector. Methods. The paper uses statistical computer modeling methods that take into account the presence of fading due to multipath propagation channel and the correlation of radio signals caused by the proximity of receiving antennas. Decision. Algorithms of detection, time-frequency synchronization and demodulation of Wi-Fi signals are considered. Methods of combining receiving channels in signal processing are proposed. The noise immunity of the proposed two-channel signal processing algorithms in the presence of quasi-stationary Relay fades and correlation of receiving channels is investigated. Novelty. Algorithms for two-channel detection, time-frequency synchronization and demodulation of Wi-Fi signals have been developed. Practical significance. The combined use of two reception channels for the detection and identification of Wi-Fi signals allows you to increase the reliability of radio monitoring systems by 4‒7 dB, even if there is a correlation between the channels.