A Frequency-Domain Iterative Cancellation Algorithm for Single-Tone Interference in OFDM systems

To solve the single-tone interference problem in orthogonal frequency division multi- plexing(OFDM) systems, an efficient frequency domain iterative interference cancellation algorithm was proposed. Firstly, the proposed algorithm made accurate estimates and reconstruction for the interference in frequency domain, and then the interference was subtracted from the raw data. To achieve a more accurate estimation of coarse interference frequency, a new method of spectrum peak search which combined with zero padding interpolation was proposed. The method effectively avoided the misjudgment of spectral peak position which was caused by spectrum leakage when interference located between the subcarriers. The accurate estimation of interference frequency was implemented by iteratively adopted a combination of frequency conversion, low pass filtering, weighted phase average(WPA) algorithm, the estimation error decreased at each iteration. The simulation results show that for the jamming to signal ratio(JSR) of -20dB above , the proposed algorithm can ensure the accurate estimation of interference parameters, make the system to achieve the bit error rate(BER) performance without interference.