Proposal and Hardware Implementation of a Partial Bandwidth Based Feature Detection Method for Sensing under Adjacent Channel Interference

Considerable efforts have been made by research entities in the world to develop sensing prototypes for digital TV (DTV) signals that can fulfill the FCC sensing requirement. FCC official test results for some sensing prototypes have shown that adjacent channel interference (ACI), which truly exists in real sensing world for DTV signals, has significantly increased the difficulty of fulfilling the FCC sensing requirement. In this work, we aim at developing a real-time sensing prototype that achieves robust sensing under ACI. A partial (channel) bandwidth based feature detection (PB-FD) method is proposed, which not only exploits identical features of DTV standards, namely the DVB-T and ISDB-T, to produce high process gain in detection, but also significantly mitigates the ACI produced by transmission power leakage. The PB-FD is specified to the center segment based FD when it is implemented into a sensing prototype to detect ISDB-T. Computer simulation results verify that PB-FD achieves superior performance over the optimal conventional sensing method, especially when sensing is performed under ACI. The PB-FD is then implemented into a sensing prototype. Hardware performance tests are performed to detect ISDB-T at FCC required threshold level of -114 dBm/6MHz under a moderate level of ACI. The test results indicate that above 0.9 detection probability and below 0.01 false alarm probability are achieved by the sensing prototype.