Viterbi IP Core User Guide

ID 683280
Date 11/06/2017
Document Table of Contents BER Estimator

The BER estimator option uses a re-encode and compare approach for estimating the number of errors in the input data.
Figure 13. BER Block Diagram

In cases where the signal-to-noise ratio is sufficiently high to allow the decoder to decode an error-free output, the BER estimation is very close to the actual channel BER. When the decoder is not decoding an error-free output, the estimated BER is higher and more random than the actual channel BER, which introduces a degree of uncertainty directly proportional to the output errors.

Note: For a TCM code, the BER block does not produce a meaningful output (numerr) because the BER block does not compute errors at the input for TCM codes.
Figure 14. Graph Comparing Actual BER with Estimated BER