A Generalization of Minimum-Shift-Keying (MSK)-Type Signaling Based Upon Input Data Symbol Pulse Shaping

In recent years, minimum-shift-keying (MSK) has gained increasing popularity as a modulation technique because of its desirable spectral properties. Quite often, the spectral concentration provided by MSK is not sufficient to meet requirements on out-of-band energy spillover. In these situations, one might apply additional input pulse shaping m such a way as to still maintain constant envelope signals. The properties of such MSK-type signals are the subject of this paper. Specific examples are included as illustrations of the theory both for the binary and
M
-ary cases.