Reducing the Complexity of Tone Injection Scheme by Suboptimum Algorithms

OFDM is a modulation scheme which is effective against multipath distortion. It has also high bandwidth efficiency. OFDM is, in fact, a multicarrier modulation method in which the available bandwidth of the channel is divided into subcarriers, and data symbols are modulated and transmitted on each subcarrier simultaneously. However, one of the most important drawbacks of this system is the large peak-to-average-power ratio (PAPR) of the transmit signal. A large PAR increases the complexity of the DAC and ADC converters and reduces efficiency of the RF power amplifier. Tone Injection is a promising technique for PAR reduction based on general additive method. This algorithm doesn´t reduce transmission rate but increase the average power of transmit signal. Furthermore, the complexity of TI method is high. To reduce the complexity, two new algorithms are proposed in this paper.