The performance of a range of 1, 2 and 4 bit/symbol pilot symbol assisted modulation (PSAM)1, 3 arrange- ments employing first-order linear, low pass, polynomial and optimum higher-order linear interpolation schemes is analysed in contrast to that of the equivalent non- coherent modems. Both the non-coherent modems as well as the coherent PSAM schemes exhibited a residual bit error rate (BER), but the best compromise in terms of performance, system delay and complexity was at- tributable to the first-order linear interpolator. In case of short interpolation buffers the polynomial interpolator slightly outperformed the low-pass and the higher-order linear optimum interpolators, but this advantage eroded in case of longer buffers. The higher complexity of the minimum mean squared error interpolator is not justifi- able in terms of performance improvements. The low- complexity linearly interpolated PSAM schemes have an improved performance in comparison to the differential schemes in case of higher order constellations, such as 4- and 16-level quadrature amplitude modulation (QAM).