Method for limiting the peak factor using an additional compensation signal in a system with orthogonal frequency division multiplexing for a Gaussian channel

Abstract

Objectives. Orthogonal frequency division multiplexing (OFDM) has become the standard for various high-speed wireless communication systems due to its several advantages, one of which is the efficient use of bandwidth. The main disadvantage of OFDM is the high peak-power-to-average-power ratio (PAPR), which is indicated by an increase in the bit error rate due to the nonlinearity of the power amplifier. The paper sets out to evaluate the possibility of reducing the PAPR value using a limitation method developed by the authors involving an additional compensation signal in a channel with white Gaussian noise, as well as to analyze its main parameters.Methods. Statistical radio engineering and computer modeling methods are used according to optimal signal reception theory.Results. The effect of the OFDM signal limitation level and the number of additional signals when using the limitation method with an additional compensation signal on the quality (reduction of transmission losses) of the OFDM signal is analyzed. The results show a decrease in the OFDM signal PAPR value, along with the dependencies of the bit error rate on the signal-to-noise ratio at fixed limitation values and a determined number of additional signals in the channel with white Gaussian noise.Conclusions. The proposed limitation method with an additional signal when transmitting an OFDM signal in a channel with white Gaussian noise provides compensation for information losses due to signal level limitations in the transmission channel. Increasing the limitation level is shown to increase the PAPR value, while varying the number of additional signals changes PAPR insignificantly. In order to ensure the effective implementation of the limitation method with an additional compensation signal, the parameters of the threshold limitation level and number of additional signals should be selected depending on the predicted signal-to-noise ratio in the system.

Keywords

• limitation method with additional signal
• peak power to average power ratio
• bit error rate
• orthogonal frequency division multiplexing
• white gaussian noise