Title :
Construction of spectrally efficient low-crest waveforms for multicarrier CDMA systems
Author :
Ho, T.F. ; Wei, Victor K.
Author_Institution :
Dept. of Inf. Eng., Chinese Univ. of Hong Kong, Shatin, Hong Kong
Abstract :
We study the spectral efficiency and the crest factor of the transmitted signals in multicarrier code division multiple access (MC-CDMA) systems. In this paper, we find a set of spectrally efficient complementary (SEC) sequences {cn} that satisfy Σn=1N(-1)ncn=0, where N is the length of the sequence used. It is shown that not only do the SEC sequences maintain the characteristic of envelope shaping for the transmitted signals, the power spectra of the multitone signals constituted from these sequences also have an advantage of sharp roll-off gradient. Methods of constructing SEC sequences are given and their applications to MC-CDMA are discussed
Keywords :
code division multiple access; frequency division multiplexing; sequences; spread spectrum communication; OFDM-CDMA; applications; code division multiple access; crest factor; envelope shaping; multicarrier CDMA systems; multicarrier modulation; multitone signals; power spectra; sharp roll-off gradient; spectrally efficient complementary sequences; spectrally efficient low-crest waveforms; spread spectrum multiple access; transmitted signals; Baseband; Discrete Fourier transforms; Linearity; Multiaccess communication; Multicarrier code division multiple access; Peak to average power ratio; Pulse shaping methods; Shape; Spread spectrum communication; Transmitters;
Conference_Titel :
Universal Personal Communications. 1995. Record., 1995 Fourth IEEE International Conference on
Conference_Location :
Tokyo
Print_ISBN :
0-7803-2955-4
DOI :
10.1109/ICUPC.1995.497063
