Abstract: A system for wireless remote control of a gateway and ordering or invocation of services provided by a headend. The remote control includes a video display and user input device or keyboard and can decompress and display compressed streaming video in some embodiments. Some species of the remote control can act as web browsers, appliance control, TIVO function control, an IP telephony telephone, a cellular telephone and/or an MP3 player. In some embodiments, the gateway and/or headend can implement TIVO-like functions under control from a wireless remote of custom design or implemented on a Personal Digital Assistant.

Abstract: Motion graphics keying in the compressed domain may be accomplished by receiving a compressed video stream comprising one or more source macroblocks, receiving a keyed graphics stream, determining which of the one or more source macroblocks overlaps with the keyed graphics stream, decoding only the one or more overlapping macroblocks to create one or more decoded macroblocks, combining the keyed graphics stream with the one or more decoded macroblocks to create a composited video stream, encoding the composited video stream to create an encoded composited video stream, and restoring the encoded composited video stream in the compressed video stream in place of the one or more overlapping macroblocks.

Abstract: Motion graphics keying in the compressed domain may be accomplished by receiving a compressed video stream comprising one or more source macroblocks, receiving a keyed graphics stream, determining which of the one or more source macroblocks overlaps with the keyed graphics stream, decoding only the one or more overlapping macroblocks to create one or more decoded macroblocks, combining the keyed graphics stream with the one or more decoded macroblocks to create a composited video stream, encoding the composited video stream to create an encoded composited video stream, and restoring the encoded composited video stream in the compressed video stream in place of the one or more overlapping macroblocks.

Abstract: A process for grouping cable modems by type/modulation profile and/or throughput ability into different logical groups. Each logical group is commanded to transmit on an upstream which has a burst profile set to effectively use the throughput ability of the cable modem. Some species monitor initial ranging bursts and separate CMs with inadequate power onto a lower throughput upstream. Some species monitor post registration data transmissions for various factors and subdivide groups into subgroups of overperformers and underperformers.

Abstract: Method and apparatus to determine the channel to which a TV tuner is tuned from a return loss ratio measurement circuit in a set top decoder. The method comprises generating a plurality of probe signals having frequencies spread throughput the TV channel band, preferably using harmonics of a zero order hold D/A converter. The return loss ratio of the reflected probe signals is then determined and stored as a signature for the TV channel and the signatures can subsequently be used along with new return loss ratio measurements to determine the TV channel to which a TV or VCR tuner is tuned.

Abstract: An improved ingress cancellation filter comprising a Fast Fourier Transform circuit which replaces the analysis filter bank of the prior art to break the incoming signal down into sub bands, an ingress cancellation filter that weights each sub band based upon the probability that the sub band is corrupted by noise, and an inverse Fast Fourier Transform circuit to put the weighted sub bands back together into an output signal and replacing the synthesis filter bank of the prior art. Also, an improved predictor filter which can be used with CDMA circuitry by initializing the predictor filter at the beginning of each spreading interval using the samples received on the first L unused codes of the spreading interval.

Abstract: A cable modem termination system is disclosed with flexible mapping of upstreams to downstreams and flexible mapping of downstreams to optical nodes and optical nodes to upstream receivers and the ability to add singe upstreams or downstreams as needed for load balancing. Multiple downstreams can share the same upstream. Multiple receivers can be coupled to the same upstream. Monitoring of upstream performance for overperforming or underperforming modems can be carried out, and new upstreams with higher and/or lower throughtput can be created to service the overperformers and/or underperformers. Modems can be grouped into logical groups with different performance levels and serviced by different upstreams or different upstream logical channels on the same upstream physical channel.

Abstract: A method and apparatus transfer digital data between a coder/decoder circuit and a signal processor. The transfer of the digital data includes (a) obtaining, at a first circuit, a block of data values having certain statistical characteristics, the first circuit being one of the coder/decoder circuit and the signal processor, (b) generating, at the first circuit, a data stream by encoding the block of data values based on the statistical characteristics thereof, (c) transferring the data stream to a second circuit via a data bus connecting the first circuit and the second circuit, the second circuit being the other of the coder/decoder circuit and the signal processor, and (d) reconstructing, at the second circuit, the block of data values by decoding the data stream received from the first circuit.

Abstract: One or more upstream line cards each include a digital or analog multiplexer front end circuit for a Cable Modem Termination System. Each upstream line card has only upstream receivers and allows a CMTS to share one or more receiver chips to receive and recover data from a larger number of input cables coupled to the front end multiplexer. A control circuit for the multiplexer uses MAP data and burst assignment data and upstream mini-slot counts for each of the input cables to determine when a burst is about to arrive on a cable and cause appropriate switching by the multiplexer or crossbar switch. In some embodiments, there is only one RF channel circuit coupled to the output of the multiplexer, so the multiplexer is controlled to couple the input cable upon which the burst is expected to the single RF channel.

Abstract: A process for grouping cable modems by type/modulation profile and/or throughput ability into different logical groups. Each logical group is commanded to transmit on an upstream which has a burst profile set to effectively use the throughput ability of the cable modem. Some species monitor initial ranging bursts and separate CMs with inadequate power onto a lower throughput upstream. Some species monitor post registration data transmissions for various factors and subdivide groups into subgroups of overperformers and underperformers.

Abstract: A process for automatically monitoring the packet error rate of a logical channel in a cable television DOCSIS data transmission system and automatically altering the bit rate on the channel or sending a message to a cable operator recommending a change in burst profile and bit rate. The preferred embodiment of the process comprises determining the dominant noise type and SNR of the channel and selecting a set of burst profiles best adapted for the dominant noise type and selecting an initial burst profile based upon the SNR. Then the packet error rate of the channel is monitored and compared to one or more thresholds to decide whether a change in bit rate is required to bring the packet error rate within limits. If a change is bit rate is indicated, automatically selecting a new burst profile with an appropriately changed bit rate and automatically generating and sending a UCD message defining the channel's new burst profile.

Abstract: A process and apparatus for sharing an upstream between multiple downstreams. A automatic discovery process carried out by the CMTS using ranging messages is used to build routing tables that define which cable modems are coupled to each downstream. The downstreams are coordinated in timestamps, MAP messages and UCD messages, and symbol clock frequency if synchronous code division multiplexed bursts are allowed upstream. Also disclosed is a flexible mapper/splitter/combiner that can electronically control switching, combining and splitting as necessary to couple multiple downstreams that share the same upstream onto the same optical nodes or split downstreams that share the same upstream among multiple optical nodes and combine upstreams from multiple HFC systems onto a single upstream input to a CMTS receiver so the CMTS receiver can be fully utilized.

Abstract: A system for bidirectional communication of digital data between a central unit and a remote unit wherein the need for tracking loops in the central unit has been eliminated. The central unit transmitter generates a master carrier and a master clock signal which are used to transmit downstream data to the remote units. The remote units recover the master carrier and master clock and synchronize local oscillators in each remote unit to these master carrier and master clock signals to generate reference carrier and clock signals for use by the remote unit receiver. These reference carrier and clock signals are also used by the remote unit transmitters to transmit upstream data to the central unit. The central unit receiver detects the phase difference between the reference carrier and clock signals from the remote units periodically and adjusts the phase of the master carrier and master clock signals for use by the central unit receiver to receive the upstream data.

Abstract: A control word generator comprised of circuitry to generate a control word to control an attenuator. The control word generator includes a counter that increments at a clock rate much higher than the refresh rate at which the error signal is recalculated. The counter is controlled by a comparator which compares the error signal to a reference value, which, starting from a programmable upper limited is decremented in the counter's incrementation rate by a programmable step size. When the reference value equals the error signal, the comparator changes state and the counter stops incrementing. The count at that time is the control word, which if everything operated instantaneously, would be the control word that would alter the attenuation sufficiently to achieve nominal power.

Abstract: A signal transmitter for sending a radio signal is made up of an input for receiving input data and a first circuit for generating an inphase signal and a quadrature signal from the input data. A second circuit produces a first signal associated with a cosine of a first frequency and a third circuit that produces a second signal associated with a sine of the first frequency. A first modulator, coupled to the first circuit and the second circuit, upconverts the inphase signal with the first signal and produces a first upconverted signal. A second modulator, coupled to the first circuit and the third circuit, upconverts the inphase signal with the second signal and produces a second upconverted signal. A third modulator, coupled to the first circuit and the second circuit, upconverts the quadrature signal with the first signal and produces a third upconverted signal.

Abstract: A system for bidirectional communication of digital data between a central unit and a remote unit wherein the need for tracking loops in the central unit has been eliminated. The central unit transmitter generates a master carrier and a master clock signal which are used to transmit downstream data to the remote units. The remote units recover the master carrier and master clock and synchronize local oscillators in each remote unit to these master carrier and master clock signals to generate reference carrier and clock signals for use by the remote unit receiver. These reference carrier and clock signals are also used by the remote unit transmitters to transmit upstream data to the central unit. The central unit receiver detects the phase difference between the reference carrier and clock signals from the remote units periodically and adjusts the phase of the master carrier and master clock signals for use by the central unit receiver to receive the upstream data.

Abstract: A system for providing video-on-demand service, broadband internet access and other broadband services over T-carrier systems including a pull multiplexer cherrypicker at the head end is disclosed. The pull multiplexer receives upstream requests and cull out MPEG or other compressed video packets, IP packets and other data packet types to satisfy the requests or to send pushed programming downstream. The downstream can be DSL or HFC. Each customer has a cable modem, DSL modem or a gateway which interfaces multiple signal sources to a LAN to which settop decoders, digital phones, personal computers, digital FAX machines, video cameras, digital VCRs etc. can be attached. Each gateway can coupled the LAN to a DSL line or HFC through a cable modem or a satellite dish through a satellite transceiver. A PSTN and conventional TV antenna interface is also provided.

Abstract: A method and apparatus for optimizing the data transfer rate over a transport layer (i.e., communication link) such as the Internet is provided. Initially the data is prepared for transmission by a transfer rate controller, then the data is encoded by a Forward Error Correction (FEC) encoder. After the data has been transferred over the transport layer, the quality of the data transfer link is assessed by an FEC decoder that determines if any errors occurred during data transfer and if errors are detected, the magnitude of the errors (i.e., FEC-correctable packets, FEC-uncorrectable packets). This information is used to generate a feedback message which is used by the transfer rate controller to adjust and optimize the data transfer rate for the link quality as determined at that point in time. By continually monitoring and assessing link quality and providing feedback to the transfer rate controller, the transfer rate can be continually adapted to the varying link quality.

Abstract: A control word generator comprised of circuitry to generate a control word to control an attenuator. The control word generator includes a counter that increments at a clock rate much higher than the refresh rate at which the error signal is recalculated. The counter is controlled by a comparator which compares the error signal to a reference value, which, starting from a programmable upper limited is decremented in the counter's incrementation rate by a programmable step size. When the reference value equals the error signal, the comparator changes state and the counter stops incrementing. The count at that time is the control word, which if everything operated instantaneously, would be the control word that would alter the attenuation sufficiently to achieve nominal power.

Abstract: A headend or central office or satellite uplink facility for receiving upstream video-on-demand requests and MPEG transport streams containing video program data and packetizing said video data into TCP/IP or UDP/IP packets and LAN packets and routing them through a switch to one or more cherrypicker multiplexers. Each cherrypicker multiplexer receives LAN packets, depacketizes the MPEG data, partially or fully decompresses the data and recompresses the data to another smaller bandwidth, and repacketizes the data into MPEG packets or TCP/IP or UDP/IP packets. The repacketized TCP/IP or UDP/IP packets are transmitted directly to the customer as TCP/IP or UDP/IP packet data. MPEG packets generated by the cherrypicker multiplexer are, optionally, encapsulated in LAN packets addressed to an IP dewrapper circuit. There, they are depacketized back to MPEG packets and transmitted to the appropriate transmitter or modem for transmitting to a customer.