Wideband TV White Space Transceiver Design and Implementation

For transceivers operating in television white space (TVWS), frequency agility and strict spectral mask fulfillments are vital. In the U.K., TVWS covers a 320-MHz-wide frequency band in the UHF range, and the aim of this brief is to present a wideband digital up- and downconverter for this scenario. Sampling at radio frequency (RF), a two-stage digital conversion is presented, which consists of a polyphase filter (PPF) for implicit upsampling and decimation, and a filter-bank-based multicarrier approach to resolve the 8-MHz channels within the TVWS band. We demonstrate that the up- and downconversion of 40 such channels is hardly more costly than that of a single channel. Appropriate filter design can satisfy the mandated spectral mask and control the reconstruction error. A field-programmable gate array implementation is discussed, capable of running the wideband transceiver on a single Virtex-7 device with sufficient word length to preserve the spectral mask requirements of the system.