soft decision and hard decision
Soft and hard decision is channel characterstic, and u can never send bits directly through channel u must have to do modulation & demodulation ( mapping / demapping stuff mentioned in spweda post)....
if we talk in cellular arena..... Hard/ Soft decision is taken for handover
Hard Handover-- Perform "break before make"-- current channel with the old BS is released b4 the new channel with the new BS is setup. its used in FDMA/TDMA and GSM system
Soft Handover-- Perform " make before break"-- new channel with the new BS is setup in paralled with the current channel with old BS. Both new and old channel are used simultaneously for the communciation. used in IS-95, CDMA2000 and WCDMA