The modulation and decoding algorithms for OFDM-MSK signals. Abstract.

Abstract. The orthogonal frequency division multiplexing signals (OFDM) suffer from high sidelobes level. The sidelobes of the OFDM-modulated tones cause the out-of-band power which can induce large interference to the incumbent communication systems. The modulation and decoding algorithms for OFDM signals with sidelobe suppression or out-of-band emission reduction are presented in the article. The proposed method is Minimum Shift Keying in each subcarriers (OFDM-MSK). The developed algorithm for signal modulation is described by means of waveform trellis associated with the trellis of information bit sequence. It is base for iterative decoding of effective block and convolutional codes (turbo-codes, Low-Density Parity Check Codes). The base of modulation and decoding algorithms for OFDM-MSK is Discrete Fourier Transform. The simulation results for developed algorithms are presented. The simulation results show high power spectral efficiency of OFDM-MSK - the largest sidelobe of OFDM-MSK is around 12.7 dB less than OFDM.

Key words: signals, side-lobe spectrum, minimum shift keying, decoding, OFDM-MSK, error performance.

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