Performance of the deliberate clipping with adaptive symbolselection for strictly band-limited OFDM systems

摘要

The performance of the strictly band-limited OFDM systems withndeliberate clipping is examined in terms of the peak-to-average powernratio (PAPR) and the resultant bit error performance. The clipping isnperformed on the OFDM signals sampled at the Nyquist rate, followed bynthe ideal low-pass filter, Since the low-pass filter considerablynenlarges the PAPR, there is a severe limitation in PAPR reductionncapability. Thus, in order to achieve further reduction of the PAPR, thenapplication of the adaptive symbol selection scheme is also considered.nIt is shown that the significant PAPR reduction with moderate complexityncan be achieved by the combination of the clipping and the adaptivensymbol selection. The price to be paid for PAPR reduction by this schemenis its performance degradation. The paper theoretically analyzes the bitnerror rate performance of the OFDM system with the Nyquist-rate clippingncombined with the adaptive symbol selection, and considers the use ofnthe forward error correction for compensation of the degradation. It isnshown that even though the clipping scheme causes severe loss innrequired signal-to-noise ratio, the use of a powerful channel codingnscheme such as turbo codes significantly alleviates the bit error ratenperformance degradation