Title :
Excess bandwidth is necessary for ISI-free double-filter receivers
Author :
Mengali, Umberto ; Vitetta, Giorgio M. ; Taylor, Desmond P.
Author_Institution :
Dept. of Inf. Eng., Pisa Univ., Italy
Abstract :
Previous work has indicated that highly effective double-filter receivers can be implemented for phase-shift keying (PSK) transmissions over linearly time-selective fading channels provided that the transmitter and receiver filters have root-raised-cosine transfer functions with unity rolloff factor. Revisiting the detection problem within the frame of maximum-likelihood (ML) sequence estimation we prove that this filter design is unique within the class of signaling pulses which are band limited to the symbol rate. It is concluded that some waste of bandwidth is inevitable for achieving ISI-free operation with double-filter receivers.
Keywords :
estimation theory; fading; filtering theory; interference suppression; intersymbol interference; maximum likelihood detection; maximum likelihood estimation; phase shift keying; receivers; telecommunication signalling; transfer functions; transmitters; ISI-free double-filter receivers; PSK transmissions; band limited signaling pulses; bandwidth; detection problem; linearly time-selective fading channels; maximum-likelihood sequence estimation; phase-shift keying; root-raised-cosine transfer functions; symbol rate; unity rolloff factor; Bandwidth; Fading; Filtering theory; Filters; Maximum likelihood estimation; Phase shift keying; Pulse shaping methods; Signal detection; Signal processing; Transmitters;
Journal_Title :
Communications Letters, IEEE
DOI :
10.1109/4234.660800
