3.4.3. Viterbi Parameters
| Parameter | Value | Description | 
|---|---|---|
| Maximum constraint length (LMAX) |   5 to 9 (hybrid) 3 to 9 (parallel)  |  
       The maximum constraint length LMAX. . | 
| ACS Units (A) | 1, 2, 4, 8, or 16 | The number of ACS units, which adds a degree of parallelism (hybrid architecture only). The range of values available depends upon the value of maximum constraint length LMAX. | 
| Traceback (v) | 8 (minimum) | The traceback length, which is the number of stages in the trellis that are traced back to obtain a decoded bit. It is typically set to 6 × L for unpunctured codes, and up to 15 × L for highly punctured codes. | 
| Softbits (softbits) | 1 to 16 | The number of soft decision bits per symbol. When softbits is set to 1 bit, the decoder acts as a hard decision decoder, and still allows for erased symbols to be entered using the eras_sym input. | 
| Bmgwide | – | The precision of the state metric accumulation. The parameter editor selects and displays the optimum value, which depends on NMAX, LMAX and, softbits. |