Minimum shift keying (MSK) is an important concept to learn in digital communications. It is a form of continuous phase frequency shift keying . In minimum phase shift keying, two key concepts are used.
(a) The frequency separation of the sinusoidals used for representing bits 1’s and 0’s are 1/2T, where T is the symbol period.
(b) It is ensured that the resulting waveform is phase continuous.