Patent application number | Description | Published |
20100066917 | Multi-Tuner Variable Low IF Receiver for Multi-Channel Applications - Systems and methods for demodulating a plurality of contiguous channels contained within a bandlimited portion of a radio-frequency (RF) input signal are provided. In an embodiment, the bandlimited portion of the RF input signal is down-converted to baseband. After down-conversion, the bandlimited portion overlaps at baseband with a mirror image of the bandlimited portion. The plurality of contiguous channels within the down-converted signal similarly overlap at baseband and subsequently occupy a bandwidth substantially equal to half that required before down-converting. Image rejection is performed in the digital domain to recover each of the plurality of overlapping channels. | 03-18-2010 |
20100067630 | Variable Low IF Receiver for Multi-Channel Applications - Systems and methods for demodulating a plurality of contiguous channels contained within a bandlimited portion of a radio-frequency (RF) input signal are provided. In an embodiment, the bandlimited portion of the RF input signal is down-converted to baseband. After down-conversion, the bandlimited portion overlaps at baseband with a mirror image of the bandlimited portion. The plurality of contiguous channels within the down-converted signal similarly overlap at baseband and subsequently occupy a bandwidth substantially equal to half that required before down-converting. Image rejection is performed in the digital domain to recover each of the plurality of overlapping channels. | 03-18-2010 |
20100197244 | Direct coupled radio frequency (RF) transceiver front end - A method and apparatus is disclosed to couple a transmission amplifier and a reception amplifier to a shared medium. An output of the transmission amplifier is directly coupled to an input of the reception amplifier to form a common connection. The transmission amplifier and the reception amplifier may receive a first amplifier bias via the common connection. In response to the first amplifier bias, the transmission amplifier provides a first communication signal to the shared medium and the reception amplifier does not provide a second communication signal from the shared medium. Alternatively, the transmission amplifier and the reception may receive a second amplifier bias via the common connection. In response to the second amplifier bias, the reception amplifier provides the second communication signal from the shared medium and the transmission amplifier does not provide the first communication signal to the shared medium. | 08-05-2010 |
20100264984 | System and Method for Over-Voltage Protection of a Power Amplifier - A system and method for over-voltage protection of a power amplifier is provided. A power amplifier is typically employed in a transmitter to amplify signals prior to transmission via a load; the load may include an antenna or a cable. As a result of an impedance mismatch between the power amplifier and its load, excess power from the power amplifier output fails to reach the load and must be dissipated by one or more transistors in the power amplifier. In severe impedance mismatch conditions, this dissipated power may damage or destroy the transistor(s). An automatic gain control (AGC) is provided for detecting a gain difference between the power amplifier and a replica power amplifier. A gain difference may signal an over-voltage situation. The AGC may be configured to adjust the gain of the power amplifier if a gain difference exists to prevent device damage. | 10-21-2010 |
20110193625 | Amplifier for Cable and Terrestrial Applications with Independent Stage Frequency Tilt - A system comprises a first amplifier stage including a first amplifier, a second amplifier stage including second and third amplifiers, and a fourth amplifier. The first amplifier stage includes an input and an output. The second amplifier stage is coupled between the output of the first amplifier stage and a first output node. The fourth amplifier is coupled between the input of the first amplifier stage and a second output node. | 08-11-2011 |