ATSC 3.0 Transmitter Carrier and Timing Offset for Co-Channel Interference Mitigation

The transition from ATSC 1.0 to ATSC 3.0 would most likely be based on the ATSC 1.0 coverage such that ATSC 3.0 stations can provide at least one fixed service with coverage greater than or equal to the replaced ATSC 1.0. However, designed with low SNR thresholds, the ATSC 3.0 robust services embedded in the same channel can be received much further away than the enhanced layer fixed services, and their coverage areas may overlap with those of the neighboring co-channel stations transmitting different programs. Such cochannel interferences (CCI) could be very high in some areas close to the boundary between the neighboring stations. Since the ATSC 3.0 system is designed with only one set of pilot sequences, the low SNR thresholds are more vulnerable to CCIs due to channel mismatch. Currently two sources causing CCIs are observed, one is the pilot overlapping, another is the Bootstrap overlapping. To resolve these problems, in this paper, carrier and timing offset techniques are proposed at the transmitter side to mitigate the CCIs, resulting in no impact to the receivers' implementation.