New QAM Complementary Sequences for Control of Peak Envelope Power of OFDM Signals

By developing new mathematical descriptions of 4^{q} (integer q\ge 2 ) quadrature amplitude modulation (QAM) constellation, a novel construction producing 4^{q} -QAM complementary sequences (CSs) of length 2^{m} (integer m\ge 2 ) is presented. The proposed sequences include the known 4^{q} -QAM CSs constructed from Cases I to III constructions, proposed by Li, as special cases. For 16-QAM CSs, the number of the resultant sequences is determined precisely. New sequences have a larger family size so as to increase the code rates. When used in orthogonal frequency-division multiplexing (OFDM) systems, new sequences possess the same peak envelope power (PEP) upper bounds as those of the known sequences referred to above.