A Flexible Radio Transmitter for TVWS Based on FBMC

In this paper a flexible radio approach for opportunistic access to the television white space (TVWS) is presented. Requirement stems from the coexistence scheme used in this band between opportunistic transmission and TV broadcast signals (or wireless microphones). To ensure non harmful interference of the TVWS signal on the incumbent services, a high adjacent leakage power ratio (ACLR) is expected. Also, flexibility is required to address the vacant channels in the UHF spectrum. Flexibility and low ACLR specifications are difficult to obtain simultaneously. The approach proposed in this paper is based on filter bank multi-carrier modulation (FBMC) scheme and a flexible hardware platform that combines RF agility and the digital filtering capability of FBMC. The hardware implementation validates that both flexibility and ACLR performance of the system are preserved even when off-the-shelf components impairments are considered. An experimental setup validates the coexistence with a TV broadcast signal and a comparison with a classical approach shows the gain in performance.