摘要:
An apparatus (20) such as a television signal receiver provides an AGC function by using multiple feedback sources which provide both narrow band and wide band AGC signals in an adaptive manner. According to an exemplary embodiment, the apparatus (20) includes a tuner (10, 15, 20, 25, 30) operative to generate first and second IF signals. A first demodulator (40) is operative to generate a first AGC signal responsive to the first IF signal. A second demodulator (50) is operative to generate a second AGC signal responsive to the second IF signal. A wide band AGC detector (60) is operative to generate a third AGC signal responsive to at least one of the first and second IF signals. A switch (70) is operative to selectively provide one of the first, second and third AGC signals to the tuner (10, 15, 20, 25, 30) responsive to a predetermined condition.
摘要:
An apparatus such as a television signal receiver employs an efficient and cost-effective signal processing architecture which enables, among other things, the reception and processing of both analog and digital signals from multiple signal sources, such as but not limited to, terrestrial and cable signal sources. According to an exemplary embodiment, the apparatus includes a first tuner operative to generate a first IF signal corresponding to a first RF signal. A first demodulator is operative to generate a first demodulated signal corresponding to the first IF signal. A second tuner is operative to generate a second IF signal corresponding to a second RE signal. A second demodulator is operative to generate a second demodulated signal corresponding to the second IF signal. A third demodulator is operative to generate a third demodulated signal corresponding to one of the first and second IF signals.
摘要:
The present invention provides a method and apparatus for processing a received television signal comprising one of a first type of television signal and a second type of television signal. Specifically, the method comprises amplifying the received television signal in response to a control signal. If the received television signal comprises the first type of television signal, the RF amplifier gain is reduced when the received television signal exceeds a first signal level. If the received television signal comprises the second type of television signal, the RF amplifier gain is reduced when the received television signal exceeds a second signal level. The second signal level is greater than the first signal level. A concomitant apparatus is also provided. As the first signal level is lower for the first type of television signal, reception of the first type of television signal is improved.
摘要:
An IF signal processing arrangement for processing both analog and digital signals is disclosed in the present application. The signal processing arrangement includes a signal source for providing one of digital and analog IF signals, a first SAW filter having an output for filtering the IF signal, digital signal processing circuitry coupled to the output for processing a filtered digital IF signal, and analog signal processing circuitry coupled to the output for processing which includes filtering a filtered analog signal.
摘要:
A tuner includes a tunable filter for selecting a desired RF signal in response to a tuning control signal and a tunable image trap for rejecting the undesired image signal corresponding to the desired RF signal responsive to the tuning control signal coupled in cascade between an RF amplifier and a mixer. The tunable trap also serves as an impedance transformation element between the tunable filter and said mixer. The arrangement is particularly useful in a tuner in which the frequency range of the local oscillator signal is below the frequency range of the received RF signals.