Modulation Schemes
The predominant schemes for High Speed PLC applications are:-
GMSK - Gaussian Minimum Shift Keying;
DSSS - Direct Sequence Spread Spectrum;
OFDM - Orthogonal Frequency Division Multiplexing.
GMSK is no longer being developed because it is inappropriate for the power line environment. DSSS cannot deliver adequate bandwidth for modern applications and is no longer considered viable above 2.5Mbps.
OFDM is now considered to be the most appropriate modulation scheme for Power Line Communications.
The maximum data rate has now been extended beyond the limits described below by merging the three operational bands into a single contiguous band and simultaneously increasing the maximum bit loading. DS2's OFDM implementation now support a raw data rate of 200Mbps.
