Digital television receiver digitizes the final intermediate frequency signal by three-stage conversion

摘要

The receiver of the DTV signal digitizes the final IF signal supplied from the 3-stage radio receiver and synchronizes the digitized final IF signal to baseband. The three-stage conversion radio receiver selects one of a plurality of DTV signals for upconversion to an electronic frequency spectrum portion over channels used for TV broadcasting, and selects one of the first IF bands generated by the upconversion. Generated by amplifying a first IF signal, amplifying a second IF signal of a second IF band generated by downconverting the amplified first IF signal, and also downconverting the amplified second IF signal The third IF signal of the third IF band is supplied. The third IF signal is the final IF signal, which is supplied to an A / D converter for linear conversion into a digitized third IF signal. The digital synchrodinning circuit synchronizes the digitized third IF signal to baseband and generates at least a real component of the digital baseband signal. Circuitry responsive to at least the real component of the digital baseband signal recovers digital data sequences representing the video and audio portions of TV programming.