Abstract
Accurate channel estimation is essential in enhancing the performance and spectral efficiency of an Orthogonal Frequency Division Multiplexing (OFDM) system especially in high mobility environment. This paper presents a Physics-Guided Graph Attention Network (PG-GAT mini v2) to be used in pilot-based channel estimation through combining the concepts of wireless channel physics and graph attention learning. Multi-head graph attention, residual learning, and Layer Normalization are used in order to optimize initial channel estimates by means of LS interpolation as well as to ensure stability of training procedure. Performance of the method is estimated in terms of NMSE, BER and standard deviation in the conditions of the high mobility Rayleigh fading channel with the carrier frequency of 2 GHz, SNRs from 0 to 30 dB and receiver velocities from 0 to 300 km/h. According to experimental results, PG-GAT mini v2 decreases the total NMSE from 0.7846 to 0.3079, which corresponds to 60.76% performance gain compared to LS interpolation.References
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