Bit-Interleaved Coded Modulation: Fundamentals, Analysis and Design

Chapter 1Introduction

1.1 Coded Modulation

The main challenge in the design of communication systems is to reliably transmit digital information (very often, bits generated by the source) over a medium which we call the communication channel or simply the channel. This is done by mapping a sequence of bits to a sequence of symbols . These symbols are then used to vary (modulate) parameters of the continuous-time waveforms (such as amplitude, phase, and/or frequency), which are sent over the channel every seconds, i.e., at a symbol rate . The transmission rate of the system is thus equal to

1.1

where the bandwidth occupied by the waveforms is directly proportional to the symbol rate