3 7 2,1) 4.2) 63) 6,3) (6,3) 4.2 2.1) Figure 4.6.6 Normal graph for trellis representation of(8,4,4)code Any realization may be transformed inta normal realization by simpe in Fi4.7.The conversion from a factor grap toa norma replications and state replications,as shown in Fig.4.6.8.In the normal graph,all graph vertices represent constraints,and the repetition constraints (or,equality constraints)are represented by vertices labeled by the symbol"=". = Figure 4.6.7 Normal graph with observed variables (represented by "dongles"),equality constraints and zero-sum constraints(represented by squares with"+"). Figure 4.6.8 As an example,Fig.4.6.9 shows the normal graph of the(8,4,4)code defined in (4.1). 9 Figure 4.6.6 Normal graph for trellis representation of (8, 4, 4) code Any realization may be transformed into a normal realization by simple conversion shown in Fig. 4.6.7. The conversion from a factor graph to a normal graph involves symbol replications and state replications, as shown in Fig. 4.6.8. In the normal graph, all graph vertices represent constraints, and the repetition constraints (or, equality constraints) are represented by vertices labeled by the symbol “=”. Figure 4.6.7 Normal graph with observed variables (represented by “dongles”), equality constraints and zero-sum constraints (represented by squares with “+”). Figure 4.6.8 As an example, Fig. 4.6.9 shows the normal graph of the (8, 4, 4) code defined in (4.1)