Optimum loop bandwidth of phase-locked modulators

For the purposes of the paper, ´modulation coding´ is a generic term used to indicate the direct upward frequency translation of a unipolar baseband signal to that of a bipolar or higher-bipolar bandpass signal within the theoretical minimum bandwidth, or a sub-multiple thereof, by means of a single modulation process: the quasi-analogue nature of the resulting intersymbol interference waveform being eminently suitable for transmission media characterised by Doppler shift and fading due to multipath propagation. Data recovery is from a reconstituted three-level waveform derived from the structural information content of the received bandpass spectrum. Extrapolation of the results obtained with an experimental model is used to identify the inherent potential of the technique for achieving operational data capacities indeterminately greater than the theoretical maximum within the Nyquist bandwidth.<>