OFDM 통신 시스템을 위한 경량 SNR 추정 알고리즘 = A Low-complexity Time-domain SNR Estimation Algorithm for OFDM Communication Systems

다국어 초록 (Multilingual Abstract)

Orthogonal Frequency Division Multiplexing technology is a multi-carrier modulation technique that uses multiple narrowband subcarriers for high speed data transmission, wherein each subcarrier carrying corresponding data bit, among which are orthogonal to each other. Because of its strong resistance to frequency selective fading, it is indispensable for broadband digital communication systems such as 4G and 5G, and wireless local area networks. However, since the unified symbol detector and channel estimation suitable for all channel environments are difficult in practical cases, algorithms using estimated SNR are used in each block of the communication system. Therefore, SNR estimation accuracy has become a major performance factor in an important OFDM wireless communication system. In this paper, we propose a simplified method of time-domain based SNR estimation based on the representative IEEE802.11 standard among OFDM communication systems. The proposed method is approximated based on time-domain SNR estimation, presented as a simple implementation without square or division, and its performance is shown by simulation. Compared with the time-domain SNR estimation without approximation, it shows low and constant errors of about 0.5 dB and 0.2 dB in the frequency fading channel environment of AWGN and channel model D, respectively. And, it is shown that the proposed method can be effectively used compared to the existing approximation method in the low SNR region that influences the performance of the communication system.

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