Patent ID: 8499328
Filing Date: 2013-07-30
Classification: H04N

Abstract:
1. Apparatus for signal modulation for transmission on a CATV cable comprising: a plurality of ports for receiving input data; each port having associated therewith a respective one of a plurality of signal generators each arranged for generating from the input data signals to be transmitted on the CATV cable to recipients; each generator including a pre-distortion component for applying a distortion to the signals to effect cancellation of distortion and noise arising in the CATV cable between the modulation and the recipient; each generator being associated with a respective one of a plurality of upconversion paths, where each upconversion path includes an output for transmission on the cable; a plurality of monitoring points defined in each of the plurality of upconversion paths; a single feedback path; a time division multiplexer arranged to switch the single feedback path between the plurality of monitoring points; the single feedback path including a downconversion path, for receiving and downconverting the signal from the selected monitoring point, and a signal processing block; the signal processing block being arranged to analyze the signal from the downconversion path and create real-time pre-distortion and noise cancellation data for use in the pre-distortion component of the signal generator.