TABLE OF CONTENTS Multilevel (M-ary) amplitude shift keying (ASK) transmits a symbol that represents N= log 2 M bits of information. An M-ary ASK signal keys the carrier frequency as to one of M discrete levels during the symbol time T s for the representation of N = log 2 M binary logic signals for the transmission of information. The modulated sinusoidal carrier signal has an amplitude of A V, a carrier frequency of f c Hz, and a 0 reference phase angle, as given by the analytical expression in Equation 3.38.
| (3.38) |  |
On the CD An M-ary ASK coherent digital communication system with AWGN and optimum receiver implemented as a correlator is shown in Figure 3.13 (see Fig3-13.svu on the CD-ROM). To facilitate the simulation in SystemVue, all of the Analysis tokens, except that for the BER token output as the Final Value token, are deleted in the simulation model Fig3-13DT. As described in Chapter 1 the SystemVue Textbook Edition does not permit tokens to be deleted.
The SystemVue simulation presented here is for an M = 4, 4-ASK signal, but can be easily extended to any 2 N-ASK ( N = log 2 M) digital communication system. A convenient set of positive, equally spaced amplitudes m j( t) for 4-level ASK is 0 V,...
