M.V. Khoroshailova – Assistant, 

Department Radio Equipment Engineering and Manufacturing, Voronezh State Technical University E-mail: pmv2205@mail.ru

I.V. Sviridova – Senior Lecturer, 

Department Radio Equipment Engineering and Manufacturing, Voronezh State Technical University

This article presents an OFDM system with LDPC coding for analyzing performance indicators, such as the additional cumulative distribution function (from the English Complementary Cumulative Distribution Function, CCDF), bit error rate (from the English Complementary Cumulative Distribution Function, BER), vector magnitude errors (from the English. Error Vector Magnitude, EVM), the modulation error rate (Modulation Error Rate, MER) in the channel AWGN using irregular LDPC codes. The simulation results show that the LDPC code in the OFDM system improves the CCDF, as well as the BER performance compared to the uncoded OFDM system. Simulation results also show that when modulating a signal on fixed subcarriers, EVM decreases, while MER increases with increasing signal-to-noise ratio (SNR) function. Hence the advantage of LDPC, which allows it to work in applications with low BER, such as wired communications, communications in deep space, etc.

An analytical description of the performance of the coded and uncoded OFDM system is presented. Compared to uncoded OFDM, simulation results show that an LDPC-encoded OFDM system has a higher modulation error rate and less EVM. Simulation results show that the LDPC-encoded OFDM system is superior to the uncoded OFDM system. In addition, when examining performance parameters in OFDM with LDPC coding, simulation results showed that a 4.4 dB reduction in PAPR was achieved in an OFDM system with LDPC coding, compared with coded OFDM, it was also shown that the OFDM LDPC system is much better than OFDM without LDPC in terms of BER, EVM and MER functions.

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