Channel estimation field design for the single carrier modulation in ieee 802.11ay

This paper describes structure of a channel estimation field for the single carrier (SC) modulation based on the IEEE 802.11ad standard supporting transmission of radio signals between devices with multiple antennas for transmission and reception (MIMO – Multiple Input Multiple Output). Channel estimation field design uses a developed set of reference sequences based on complementary Golay pairs having similar statistical characteristics. All sequences are orthogonal to each other and each complementary pair has a pair in the set with zero cross-correlation property between them. Usage of this property allows to cancel out interstream interference during channel estimation procedure. A key property of the developed set is a common hardware architecture for a generator and correlator. Proposed structure of the channel estimation field is flexible and can be extended to arbitrary number of spatial streams for transmission. To analyze influence of the proposed channel estimation field on system performance, dependence of packet error rate on signal to noise ratio (SNR) was simulated for MIMO configuration with two transmit and two receive antennas for real and ideal channel estimations. System performance is analyzed in two channel models: the line of sight channel and the Rayleigh channel corresponding to the best and worst case of the signal propagation. It was shown that degradation of the SNR operating points depending on a modulation-coding scheme is in range 0.6-1.1 dB for the line of sight channel model and 0.7-1.5 dB for the Rayleigh channel model. This solution is already adopted by the IEEE 802.11ay standardization group.