##### From Digital Communication Systems Using SystemVue

## MULTILEVEL (M-ARY) FREQUENCY SHIFT KEYING

Multilevel (M-ary) frequency shift keying (FSK) transmits a symbol than represents *N*= log _{2} Mbits of information. An M-ary FSK signal *keys* the carrier frequency to one of M discrete frequencies during the symbol time *T _{s}* for the representation of

*N*binary logic signals for the transmission of information. The modulated sinusoidal signal has an amplitude of

*A*V, a carrier frequency of

*f*Hz, and a 0 reference phase angle, as given by the analytical expression in Equation 3.54.

_{c}(3.54) | |

### SystemVue Simulation of M-ary FSK

** On the CD ** An M-ary FSK coherent digital communication system with AWGN and optimum receiver implemented as a correlator is shown in Figure 3.17 (see Fig3-17.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 Fig3-17DT. As described in Chapter 1 the SystemVue Textbook Edition does not permit tokens to be deleted.

Figure 3.17: A 4-FSK coherent digital communication system with BER analysis.

The SystemVue simulation presented here is for an *M* = 4, 4-FSK, but can be easily extended to any 2 * ^{N}*-FSK (

*N*= log

_{2}M) digital communication system. This M-ary FSK system is similar to the Gray-coded M-ary ASK system shown in Figure 3.13. The 4-FSK signals are assumed to have equal apriori probabilities of occurrence (

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MULTILEVEL (M-ARY) PHASE SHIFT KEYING A multilevel (M-ary) phase shift keying (PSK) signal shifts the phase angle of the carrier frequency to one of M discrete values during the symbol time T s for...

BINARY FREQUENCY SHIFT KEYING Binary frequency shift keying (FSK) shifts the carrier frequency to one of two discrete frequencies during the bit time T b for the representation of binary logic...

BINARY PHASE SHIFT KEYING Binary phase shift keying (PSK) shifts the phase angle of the carrier frequency to one of two discrete phases during the bit time T b for the representation of binary logic...

BINARY AMPLITUDE SHIFT KEYING Binary amplitude shift keying (ASK) keys the carrier frequency as one of two discrete levels during the bit time T b for the representation of binary logic signals for...

OVERVIEW Bandpass modulation techniques encode information as the amplitude, frequency, phase, or phase and amplitude of a sinusoidal carrier. These bandpass modulation schemes are known by their...