Phase jitter sensitivity of rotationally invariant 8 and 16 point trellis codes

Prabhu (1976) examined the sensitivity of uncoded PSK modulations to carrier phase jitter. A Gaussian phase jitter model was assumed. The same study is conducted for trellis coded PSK and QAM modulations. Rotationally invariant codes are considered and an explicit design procedure is included. Through digital computer simulation it was found that for practical values of RMS phase jitter coding gains for rotationally invariant codes are either maintained or enhanced through trellis coding. Four examples are presented which represent the design procedure. The phase jitter sensitivity is given in each case. Analytic expressions are also derived for the differential encoding rules to be used in the 8 and 16 point examples presented.<>