Abstract: A novel apparatus and method of reduced power consumption for battery backup operation of a communication device such as a cable modem. When the cable modem senses a failure of the external power source it requests from the cable head-end to switch from multi-channel DOCSIS 3.0 operation to single-channel DOCSIS 2.0 operation. In response to approval by the cable head-end, the cable modem shuts down multi-channel circuits in the PHY such as the wideband analog to digital converter (ADC) which is normally used during multi-channel operation. In its place, it activates narrowband circuitry such as a narrowband ADC which consumes far less power. Tuner filter circuits are also swapped to match the reduced bandwidth requirements of battery backup operation. To further reduce power, the narrower bandwidth requirements during battery backup operation permit the linearity of a programmable gain amplifier (PGA) in the upstream path to be reduced.

Abstract: One embodiment of the present invention includes a method for controlling a gain of a wideband signal. The method comprises adding a virtual channel to the wideband signal, the wideband signal comprising at least one channel. The method also comprises monitoring an output power associated with the wideband signal that includes the at least one channel and the virtual channel. The method further comprises setting a gain factor to achieve a predetermined output power of the wideband signal and amplifying the wideband signal based on the gain factor.

Abstract: A novel single chip tuner integrated circuit (IC) for multiple video reception in a cable modem. The tuner circuit is well suited for use in cable modem systems adapted to implement the DOCSIS 3.0 specification which specifies multiple simultaneous video channel reception. The single-chip tuner integrated circuit comprises a plurality of tuner sub-circuits wherein each tuner sub-circuit is operative to generate a single output channel, determined in accordance with a tune commend input. The tune command input is used to generate a frequency reference signal that is input to a corresponding tuner sub-circuit. The frequency reference signal for a tuner sub-circuit is mixed with an input RF receive signal from the CATV input to the cable modem to generate a baseband channel. The baseband channel is subsequently filtered, amplified and input to the PHY circuit wherein undergoes analog to digital conversion (ADC) before being input to a baseband processor.

Abstract: A novel apparatus and method of reduced power consumption for battery backup operation of a communication device such as a cable modem. When the cable modem senses a failure of the external power source it requests from the cable head-end to switch from multi-channel DOCSIS 3.0 operation to single-channel DOCSIS 2.0 operation. In response to approval by the cable head-end, the cable modem shuts down multi-channel circuits in the PHY such as the wideband analog to digital converter (ADC) which is normally used during multi-channel operation. In its place, it activates narrowband circuitry such as a narrowband ADC which consumes far less power. Tuner filter circuits are also swapped to match the reduced bandwidth requirements of battery backup operation. To further reduce power, the narrower bandwidth requirements during battery backup operation permit the linearity of a programmable gain amplifier (PGA) in the upstream path to be reduced.