TELEVISION RECEIVER HAVING EACH INTERMEDIATE FREQUENCY AMPLIFIER FOR DIGITALLY-SYNCHRODYNED VSB AND QAM DIGITAL TELEVISION SIGNALS

摘要

PURPOSE: A television receiver having each IF amplifier for digitally-synchrodyned VSB(Vestigial SideBand) and QAM(Quadrature Amplitude Modulation) digital television signals is provided to receive the digital television signals regardless of whether the digital television signals are transmitted by using a QAM mode of a main carrier or by using VSB amplitude modulation mode of the main carrier. CONSTITUTION: The first and the second IF amplifier chains provide the first and the second final IF response signals for received digital television signals. The first and the second ADCs(19, 29) digitally convert the first and the second final IF response signals. If a selected DTV(Digital Television) signal is a QAM signal, a QAM synchrodyning circuit(4) synchrodynes the first final IF signal to a baseband signal, to generate a real number sample stream and an imaginary sample stream of an interleaved QAM symbol code. If the selected DTV signal is a VSB signal, a VSB synchrodyning circuit(5) synchrodynes the first final IF signal to a baseband signal, to generate a real number sample stream and an imaginary sample stream of an interleaved VSB symbol code.