Abstract: A guide member for accommodating a removable module is formed from a thermally conductive material having at least one thermally conductive element to provide a new primary heat dissipation path to manage thermal energy generated by operation of the module. The guide member may also be used to guide the module into proper connection with a module connector which electrically connects the circuit on the module with other circuitry. A plurality of thermally conductive elements, such as spring fingers, ribs and fins, provide additional thermal heat dissipation paths and enhance the rigidity of the guide members.

Abstract: The performance of a multiphase and/or multiple amplitude receiver, such as a 64/256 quadrature amplitude modulation (QAM) receiver, is improved in the presence of single and multiple echoes. A moving window adaptive decision feedback equalizer (DFE) is provided according to the adaptive equation Cn(k+1)=Cn(k)−&Dgr;·W(k)·En(k)·Xn(k), where &Dgr; (delta) is the step size, Cn(k) is the tap value of tap n for the k symbol, En(k) is the error output at the symbol k, Xn(k) is the received signal for pre-cursor taps (FFE) and past decision output for post-cursor taps (DFE), and W(k) is the sliding window function at symbol k. In the adaptation process, some coefficients are fixed while other taps are being adapted. In particular, the adaptation is focused on a group of taps which correspond to received echoes.

Abstract: A semiconductor-based gain equalization device, method and apparatus. In one aspect of the present invention, an apparatus according to an embodiment of the present invention includes a semiconductor material. An optical path is included through the semiconductor material and is optically coupled to receive and transmit an optical beam. The gain equalization device is disposed in the semiconductor material. The optical gain equalization device includes a plurality of Bragg gratings disposed in the semiconductor material optically coupled to receive and transmit the optical beam. Each of the plurality of Bragg gratings have a different Bragg wavelength. The optical beam is to be directed from plurality of Bragg gratings with a non-uniform spectral response to compensate for the spectral non-uniformity of optical amplifiers.

Abstract: A semiconductor-based tunable optical dispersion compensation method and apparatus for multiple channels. In one aspect of the present invention, an apparatus according to an embodiment of the present invention includes a semiconductor material. An optical path through the semiconductor material is included. The optical path is optically coupled to receive an optical beam. A nonlinearly chirped Bragg grating is disposed in the semiconductor material. The optical path includes the nonlinearly chirped Bragg grating to substantially reduce chromatic dispersion in the optical beam.

Abstract: If the circuitry for processing television and other data signals conventionally contained in a set-top terminal is incorporated directly into a television set, heat from a removable point-of-deployment module inserted into the television set to connect with that circuitry can be primarily dissipated by providing a guide of a thermally conductive material that is in contact with both the module and the electromagnetic interference shield of the television set. This applies in either a cathode ray tube television set or a flat panel display television set. In a flat panel television set, the interference shield takes the form of a shield bracket, which is also used to support the flat panel display. In either case, heat generated by the module is conducted to the shield or shield bracket and then released by convection. Alternatively, the module can, in either case, be installed in direct physical contact with the shield or shield bracket.

Abstract: A method and system for enhancing digital video transmission to set-top boxes improves the performance of a hybrid analog and digital video transmission system, for example, an AM-VSB QAM video transmission system, by selecting a digital channel map based on the relative magnitude and frequency locations of CSO and CTB distortions and the analog channel frequency plan. A variable interleaver may also be implemented in the video transmission system to further reduce the CSO and CTB distortions.

Abstract: The port for a removable module of a set-top box in a cable television system incorporates guide members of a thermally conductive material to provide a new primary heat dissipation path to manage thermal energy generated by operation of the module. The guide members may also be used to guide the module into proper connection with a module connector which electrically connects the circuit on the module with the circuitry of the set-top box. The guide members may be attached to the chassis of the set-top box or integrally formed in the chassis. Thus, heat from the module is provide directly to the chassis of the set-top box from which it is released by convention into the ambient environment.

Abstract: A method is presented comprising tuning a receiver of a broadband signal to a channel within the broadband signal to receive information including one or more cable modem operating parameters, and updating one or more operating parameters of the cable modem in accordance with the received information.

Abstract: A method is presented comprising tuning a receiver to a first of a plurality of channels within a received broadband signal, searching for a pilot tone within the tuned channel, and updating one or more operating parameters of a cable modem to denote the tuned channel is a data channel if the pilot tone is detected.

Abstract: A method is presented comprising receiving a broadband signal at a receiver in accordance with a first modulation technique, tuning the receiver to a channel within the broadband signal, and modifying one or more operational parameters of the receiver to demodulate the channel in accordance with a second modulation technique to determine whether the channel is a data channel.

Abstract: A method is provided for transporting variable length packets such as IP packets and fixed length packets of length N, such as MPEG video packets, in standard digital transmission frames such as DS-3 frames. Each frame comprises a plurality P of sections having a fixed length M which is greater than N. A fixed length trailer is added to each of the variable length packets. Each variable length packet with the added trailer is segmented into an integer number of segmented packets of length N. Padding bits are added if necessary to provide the integer number of segmented packets. A header and trailer are added to each of the segmented packets and fixed length packets to expand them into an expanded packet length M. P of the expanded packets are combined into a frame for transmission.

Abstract: Interference and/or nonlinear distortions are reduced in a signal communicated from a transmitter to a receiver. To reduce interference, the transmitter is momentarily disrupted, during which time the receiver analyzes interference on the communication path to determine the frequency of at least one peak thereof. Information is communicated from the receiver to the transmitter identifying the frequencies of the interference peaks. Based on this information, the transmitter pre-distorts the signal to accentuate the signal magnitude at the identified frequencies. The pre-distorted signal is then communicated to the receiver, where it is filtered to attenuate the signal magnitude at the identified frequencies. An adaptive scheme periodically determines the interference peak frequencies. For nonlinear distortion cancellation (e.g., CSO/CTB), there is no need to disrupt the transmitter since the frequencies of the distortion are already known.

Abstract: Interference and/or nonlinear distortions are reduced in a signal communicated from a transmitter to a receiver. To reduce interference, the transmitter is momentarily disrupted, during which time the receiver analyzes interference on the communication path to determine the frequency of at least one peak thereof. Information is communicated from the receiver to the transmitter identifying the frequencies of the interference peaks. Based on this information, the transmitter pre-distorts the signal to accentuate the signal magnitude at the identified frequencies. The pre-distorted signal is then communicated to the receiver, where it is filtered to attenuate the signal magnitude at the identified frequencies. An adaptive scheme periodically determines the interference peak frequencies. For nonlinear distortion cancellation (e.g., CSO/CTB), there is no need to disrupt the transmitter since the frequencies of the distortion are already known.