During the last years, Wi-Fi wireless local area networks along with cellular mobile systems became the most massive and widespread radio technologies. Advancement and technical development of the Wi-Fi systems continues and are performed by the IEEE 802.11 standards committee. Each new generation of the systems includes new technologies that allow to significantly enhance the technical parameters of Wi-Fi networks. The IEEE 802.11a standard was one first where the OFDM modulation was used that led to essentially improved system performance in wideband frequency selective propagation channels. Multiple antenna arrays at the transmit and received sides of the radio link were for the first time used in the IEEE 802.11n systems to realize the MIMO-OFDM concept. Afterwards, in 2008-2009, two perspective directions of further development for Wi-Fi systems were identified by the IEEE 802.11 committee. The first direction being developed within the IEEE 802.11ac standard framework further advances the MIMO-OFDM system concept with application of the multi-user MIMO modes in the traditional frequency bands of 2-5 GHz. The second direction, to be implemented by the IEEE 802.11ad standard, assumes exploitation of the new 60 GHz frequency band, which allows using ultra-wideband frequency channels with the frequency of a single channel of up to 2 GHz and achieving the throughputs of up to several Gbps.

The presentation considers basic physical layer technologies of the above mentioned Wi-Fi standards. An overview of the standardization process for those technologies is provided including the participation of the Nizhny Novgorod Lab of Intel Corporation and the University of Nizhny Novgorod.