A TPS decoder for a DVB-T digital television system includes an input signal estimator, a masking device, a vector index determinator and a lookup table device. The input signal estimator receives a plurality of frequency-domain input signals and a plurality of channel measure signals to thereby produce a plurality of estimated input signals. The masking device performs a masking operation on the estimated input signals to thereby produce a plurality of masking signals. The vector index determinator is based on the masking signals to determine a vector index corresponding to the frequency-domain input signals. The lookup table device is based on the vector index to produce a codeword.