Abstract: A method and an apparatus are employed for individually monitoring the connectivity status of cables connected at a cable modem termination system (CMTS), where the cables conduct upstream and downstream RF communication signals. The monitoring is self-contained within the CMTS. The monitoring is achieved by producing a reference signal having a frequency outside the frequency range of the RF communication signals. The reference signal is injected onto the RF communication signal. The power level of the reference signal is detected within the CMTS, whereby the power level correlates with an expected cable load impedance. A DC control voltage based on the detected power level of the reference signal is generated, which allows a controller to determine the connectivity statuses of the connected cables.

Abstract: A method and an apparatus are employed for individually monitoring the connectivity status of cables connected at a cable modem termination system (CMTS), where the cables conduct upstream and downstream RF communication signals. The monitoring is self-contained within the CMTS. The monitoring is achieved by producing a reference signal having a frequency outside the frequency range of the RF communication signals. The reference signal is injected onto the RF communication signal. The power level of the reference signal is detected within the CMTS, whereby the power level correlates with an expected cable load impedance. A DC control voltage based on the detected power level of the reference signal is generated, which allows a controller to determine the connectivity statuses of the connected cables.

Abstract: In a channelized system having a plurality of channels, an input spectrum having a plurality of signals is received by a receiver (10). A first attenuation value (V1) is applied to a first variable gain device (12) and a second attenuation value (V2) is applied to a second variable gain device (14), wherein the first variable gain device (12) and the second variable gain device (14) are within a common signal path. The receiver (10) is tuned to a desired channel and a first power level is measured within the desired channel. The receiver (10) is selectively tuned to at least one additional channel and a second power level within the at least one additional channel is measured, independent of the first power level. Based on measuring the power levels, a first modified attenuation value is applied to the first variable gain device (12) and a second modified attenuation value is applied to the second variable gain device (14).

Abstract: A loop filter and amplifier (206) is configured to generate a control voltage (VC) by applying low gain to a correction voltage (VP) in response to an input signal (VH/L) indicating that the VCO (202) is to operate at low frequencies and applying high gain to the correction voltage in response to the input signal indicating that the VCO is to operate at high frequencies. A loop filter and amplifier (306) is configured to generate a control voltage (VC) by shifting the control voltage by an amount determined by an offset voltage (VOFF) and by adjusting the control voltage with a correction voltage (VP). An operational amplifier (310) is configured to generate a difference between the amount determined by the offset voltage and the correction voltage.

Abstract: The present invention is a method and system for extracting information from a received signal with minimal loss due to noise. The system comprises of a transformer, for correlating the received signal to a wavelet function and producing wavelet decomposition coefficients, and a threshold circuit, which is responsive to the received signal, for applying predetermined threshold values based on the type of signal. Also included in the system is a filter, coupled to the transformer and threshold circuit, for altering the wavelet decomposition coefficients produced by the transformer using threshold values applied by the threshold circuit to produce altered wavelet coefficients from which the received signal is reconstructed with reduced noise.

Abstract: The present invention is a method and system for extracting information from a received signal with minimal loss due to noise. The system comprises of a transformer, for correlating the received signal to a wavelet function and producing wavelet decomposition coefficients, and a threshold circuit, which is responsive to the received signal, for applying predetermined threshold values based on the type of signal. Also included in the system is a filter, coupled to the transformer and threshold circuit, for altering the wavelet decomposition coefficients produced by the transformer using threshold values applied by the threshold circuit to produce altered wavelet coefficients from which the received signal is reconstructed with reduced noise.

Abstract: A direct down conversion receiver includes a signal filter having a selectable frequency response for receiving an input signal. The filtered signal is amplified by a variable gain amplifier, and the amplified signal is received as input by an analog-to-digital converter. The analog-to-digital converter generates a series of digital samples representative of the filtered signal. A controller measures a corresponding peaking ratio of the filtered signal from the series of digital samples for each of a plurality of frequency bands and selects the frequency response of the signal filter as a function of the measured peaking ratios. The signal filter may include an adjustable highpass filter and an adjustable lowpass filter.

Abstract: A receiver system for rapidly selecting a desired downstream receiver channel from the broad cable frequency bandwidth. The system first makes a coarse scan of the signal spectrum to identify the most probable frequency zones, and subsequently makes a high resolution scan of the selected frequency zones to identify the desired channel.