Abstract: A robust integer carrier frequency offset estimation method for OFDM systems is disclosed. Compared with conventional methods which use either two consecutive OFDM symbols or only one training symbol, the method is insensitive to the timing offset as long as the channel spread is shorter than the OFDM cyclic prefix length. Most importantly, it does not require any information on the scrambling code used in systems such as STiMi. The method improves the accuracy of integer carrier frequency offset, especially in channels with long and strong echoes. It offers the receiver more freedom in setting the FFT window since it is insensitive to the timing offset.

Abstract: A robust integer carrier frequency offset estimation method for OFDM systems is disclosed. Compared with conventional methods which use either two consecutive OFDM symbols or only one training symbol, the method is insensitive to the timing offset as long as the channel spread is shorter than the OFDM cyclic prefix length. Most importantly, it does not require any information on the scrambling code used in systems such as STiMi. The method improves the accuracy of integer carrier frequency offset, especially in channels with long and strong echoes. It offers the receiver more freedom in setting the FFT window since it is insensitive to the timing offset.

Abstract: For digital TVs, transmission parameter signaling (TPS) data are normally required to be decoded and checked in every signal frame. In the Chinese DTV-T standard, these TPS data are transmitted over subcarriers in a contiguous frequency band of width 72 kHz, with the result that the SNR for these subcarriers may drop to a very low value due to lack of frequency diversity. The TPS data decoding error rate may rise significantly, severely impacting the DTV performance. A reliability detector is used to provide a reliability indication of the decoded TPS data. If this indication indicates that the decoded TPS data are likely to be incorrect, the receiver may discard the presently decoded TPS data and use the previously decoded ones (obtained when the reliability measure was high) or may take other appropriate actions. The reliability detector may include an SNR estimator, a comparator, and possibly storage.