Continuous phase modulation: Difference between revisions

Revision as of 13:17, 27 November 2009

Revision as of 19:00, 17 February 2010

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not continuous. The spectral efficiency of CPM can be further improved by using a smooth phase trajectory.

This is typically accomplished by filtering the phase trajectory prior to modulation, commonly using a Raised Cosine

or a [[Gaussian filter]]. The raised cosine filter has azero strictlycrossings finiteoffset durationby exactly one symbol time, and so can yield a ''full-response'' CPM

waveform that prevents [[Intersymbol interference|Intersymbol Interference (ISI)]].