Title :
TFO Q2PSK: a multi-dimensional spectrally efficient modulation scheme
Author :
Waldeck, B.H. ; Swanepoel, S.A. ; Linde, L.P.
Author_Institution :
Dept. of Electr. & Electron. Eng., Pretoria Univ., South Africa
Abstract :
This paper investigates various pulse shaping techniques aimed at increasing the spectral efficiency of a Q2PSK system. It will be shown that, other than matched filter based schemes, time orthogonal modulation schemes can also be used to increase the spectral efficiency of the modulation schemes. Expressions for the spectra and impulse responses of the different pulse shapes used in the various techniques will be presented. The spectral efficiency of the different pulse shaping techniques will be compared using the percentage power captured as a function of bandwidth. Further numerical results will include the maximum intersymbol interference (ISI) and cross-symbol interference (CSI) experienced for the different techniques. It is concluded that there exists a large number of pulse shaping techniques which can be used to increase the spectral efficiency of multi-dimensional modulation schemes
Keywords :
intersymbol interference; matched filters; modulation; pulse shaping; quadrature phase shift keying; radiofrequency interference; transient response; CSI; ISI; TFO Q2PSK; cross-symbol interference; impulse responses; matched filter based schemes; maximum intersymbol interference; multi-dimensional modulation scheme; pulse shaping techniques; spectrally efficient modulation scheme; time orthogonal modulation schemes; time-frequency orthogonal; Bandwidth; Decoding; Finite impulse response filter; Frequency; Interference; Phase shift keying; Pulse shaping methods; Sampling methods; Shape; Transmitters;
Conference_Titel :
Communications and Signal Processing, 1998. COMSIG '98. Proceedings of the 1998 South African Symposium on
Conference_Location :
Rondebosch
Print_ISBN :
0-7803-5054-5
DOI :
10.1109/COMSIG.1998.736918