Title :
Analyzing spectral regrowth of QPSK and OQPSK signals
Author :
Raich, Raviv ; Zhou, G. Tong
Author_Institution :
Sch. of Electr. & Comput. Eng., Georgia Inst. of Technol., Atlanta, GA, USA
Abstract :
A comparison is made between the spectral regrowth of quadrature phase shift keyed (QPSK) and offset QPSK (OQPSK) signals as they go through nonlinear amplifications. Contrary to existing approaches that assume the power amplifier input is Gaussian, our analysis is carried out without the Gaussian assumption, by using higher-order statistics. We show that it is possible to assess quantitatively whether and how much OQPSK is beneficial in reducing spectral regrowth. Simple closed form formulas are obtained when the pulse shape filter is time-limited. A particular measure of spectral broadening is also provided
Keywords :
UHF power amplifiers; digital radio; higher order statistics; mobile radio; nonlinear filters; pulse shaping; quadrature phase shift keying; spectral analysis; IS-95; OQPSK; closed form formulas; higher-order statistics; nonlinear amplification; offset QPSK; power amplifier; quadrature phase shift keying; spectral broadening; spectral regrowth; time-limited pulse shape filter; Filters; High power amplifiers; Higher order statistics; Particle measurements; Pulse amplifiers; Pulse shaping methods; Quadrature phase shift keying; Shape; Signal analysis; Spectral analysis;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 2001. Proceedings. (ICASSP '01). 2001 IEEE International Conference on
Conference_Location :
Salt Lake City, UT
Print_ISBN :
0-7803-7041-4
DOI :
10.1109/ICASSP.2001.940552
