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: An analog multiplexer front end circuit for a Cable Modem Termination System receiver to utilize one or a handful of CMTS receiver chips to receive and recover data from a larger number of input cables coupled to the analog multiplexer. A control circuit for the multiplexer uses MAP data and upstream mini-slot counts for each of the input cables to determine when a burst is about to arrive on an cable. 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. In other embodiments, there are multiple RF channels so the multiplexer is controlled to connect each input cable on which a burst is expected to an available W channel. In some embodiments, the sample data generated by each RF channel is buffered and an arbiter picks one burst at a time for application to the input of a CMTS receiver.

Abstract: A DOCSIS 2.0 compatible sniffer which can receive legacy DOCSIS 1.x TDMA bursts as well as DOCSIS 2.0 SCDMA bursts. One embodiment uses two cable modems in the sniffer, one to capture downstream data bursts and the other to capture downstream messages and to recover the downstream symbol clock and generate an upstream reference clock which is phase coherent with the recovered downstream symbol clock. The reference clock is used by a cable modem termination system to capture upstream SCDMA DOCSIS 2.0 bursts. DOCSIS 1.x TDMA bursts may also be captured. Other embodiments use a DOCSIS 2.0 compatible modem in the sniffer to lock onto a downstream, register as a cable modem in the system and capture downstream messages in order to derive the correct timing to generate control signals to control burst capture circuitry in the sniffer to capture DOCSIS 1.x and 2.0 upstream bursts.

Abstract: Circuitry and processed carried out thereby are disclosed for transmitting video-on-demand and interactive service data and other service data on an MPEG multiplex and sending management and control data including conditional access EMM key data in-band in said MPEG multiplex in MPEG packets having the DOCSIS PID. Processes to send conditional access data by sending ECM messages containing control words encrypted with session keys in said MPEG multiplex and sending EMM messages containing session keys encrypted with private set top box users keys are disclosed. The EMM messages are sent in-band in MPEG packets having the DOCSIS PID to only the set top boxes that request them and which have ordered an encrypted service. A head end with routing/switching capability to route MPEG transport streams encapsulated in IP packets is also disclosed.

Abstract: Circuitry and processes carried out thereby are disclosed for implementing simple single tuner set top box decoders which do not require a separate tuner for an out of band management and control channel. Removable smart card conditional access circuitry and replaceable modules having decoding circuitry for different compression schemes and encoding circuitry for different format television circuits is disclosed. An embodiment with a single tuner and a full DOCSIS compatible modem which can interface to personal computers, etc. is also disclosed to make the set top box a simple, inexpensive home gateway is also disclosed.

Abstract: A multichannel, mixed mode cable modem termination system receiver capable of receiving multiple channels of digital data transmitted on one or more hybrid fiber coaxial cable systems, each the channels being either single mode or mixed-mode. Mixed mode channels are time division multiplexed and have overlapping bandwidth and each sub-channel of a mixed mode channel can have a different center frequency, symbol rate and/or multiplexing type. The receiver is comprised of a plurality of analog front end circuits coupled to the various HFC systems, each selective coupled to any one of a plurality of digital front end receivers. Control circuitry controls these circuits to receive multiple mixed-mode or single mode channels, simultaneously if necessary. An arbiter decides which bursts get processed first in a back end shared demodulator which recovers the data from each burst.

Abstract: A gateway for coupling a local area network coupled to a plurality of peripheral devices at a customer premises to one or more external networks that deliver analog signals bearing analog video such as regularly scheduled CATV, terrestial or satellite C-band broadcasts, or modulated with digital video-on-demand data, or IP packets bearing IP telephony data or data from the internet. The preferred construction is modular so that single expansion modules to interface only to DSL lines or only to a satellite dish or only to HFC, or some combination thereof may be added as needed. The gateway may be a standalone circuit also with hardwired interfaces to one or more external network types. The incoming analog signals are either digitized, compressed and distributed on the local area network or the digital data thereon is recovered and packetized as an IP packet if not already so packetized and distributed via a router process to the device that requested the data via the local area network.

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 process for refurbishing analog set top tuner/decoders which are not compatible with digital cable to convert same into a digital set top tuner/decoder which can tune any channel on a digital cable system and convert the digital data received on that channel into a video signal. The process comprises forming a replacement circuit and mounting said replacement circuit on the motherboard of the target set top tuner/decoder and then making circuit breaks at the appropriate points on the motherboard of said target set top tuner/decoder and connecting the appropriate points on the replacement circuit to the appropriate circuit breaks to complete the conversion.

Abstract: A process for refurbishing analog set top tuner/decoders which are not compatible with digital cable to convert same into a digital set top tuner/decoder which can tune any channel on a digital cable system and convert the digital data received on that channel into a video signal. The process comprises forming a replacement circuit and mounting said replacement circuit on the motherboard of the target set top tuner/decoder and then making circuit breaks at the appropriate points on the motherboard of said target set top tuner/decoder and connecting the appropriate points on the replacement circuit to the appropriate circuit breaks to complete the conversion.

Abstract: A process for refurbishing cable modems which are not compliant with DOCSIS 2.0 to create a cable modem which is compliant with DOCSIS 2.0 and which reuses many of the components and circuits of the non compliant target modem in the circuitry which is compliant with DOCSIS 2.0. A replacement circuit board is mounted on the PCB of the target modem and connected to predetermined points to replace the functionality that is not DOCSIS 2.0 compliant with functionality that is.

Abstract: An impulse detector which can detect both low and high levels of impulse noise in a CDMA system is comprised of circuitry to calculate the background noise level in unused codes. Another circuit calculates the average noise power in the unused codes of each spreading interval to output the noise power per spreading interval. This average is continuously averaged over spreading intervals by another circuit which outputs the average background noise power. A comparator compares the noise power in the current spreading interval with the background noise power plus a programmable threshold and generates an erasure indication if the background noise power plus a discrimination threshold is exceeded.

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 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 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 method of determining when cable modems in a distributed digital data delivery service over cable TV hybrid fiber coaxial cable network have a headroom problem and resolving said problem. The method involves measuring the burst power from each cable modem, and if the burst power is too low, requesting the cable modem whose burst power is too low to increase its transmit power, and keeping track of which modems have been requested to increase their power. If a predetermined number of requests to increase power have not resulted in the cable modem transmitting with sufficient power for reliable reception, the cable modem is listed as having a headroom problem. Subsequent requests for upstream bandwidth from all modems with headroom problems are analyzed to determine if the requested burst size is too large and will result in a headroom problem. If so, a calculation as to the maximum number of spreading codes that each modem with a headroom problem can simultaneously transmit on without a headroom problem.

Abstract: A signal distribution system to save on the cost of cable modems for cable TV headend operators who wish to deliver broadband digital data services, DSL, video-on-demand or POTS service over their HFC CATV delivery networks. All species within the genus have a shared cable modem and a filtration and combining circuit comprised of a plurality of diplexer filters or junction boxes or both which mix baseband packet data with analog CATV signals onto coax drop lines coupled to the various subscribers and connect POTS or DSL signals onto twisted pair portions of siamese cables. Various species have the cable modem feeding digital data or packets of DOCSIS or other data or digitized DSL signals sent over the HFC to the cable modem or digitized POTS signals send over the HFC to the cable modem to either a packet switch, a DSL concentrator, a voice-over-IP gateway or some combination of the above.

Abstract: A pipelined digital data receiver for a cable TV headend which is capable of receiving DOCSIS 1.0 or 1.1 or advanced PHY TDMA or SCDMA bursts having programmable symbol rates and programmable modulation types as well as a host of other burst parameters such at Trellis code modulation on or off, scrambling on or off, various values for Reed-Solomon T number and codeword length. The receiver has an RF section to filter and digitize incoming RF signals. It also has an input section to detect impulse noise and do match filtering and despread SCDMA bursts. A timing recovery section recovers the symbol clock and detects the start of bursts and collisions. A rotational amplifier and equalizer calculate and track gain, phase and frequency offsets and correct symbols and calculates equalization coefficients. A decoder section decodes TCM and non TCM bursts, and a Reed-Solomon decoder section reconstructs RS codewords and uses them to error correct the payload data.

Abstract: A method and apparatus for interleaving symbols from a one dimensional TDMA 802.14 or MCNS minislot or other TDMA stream into two dimensional arrays in code and time for transmission on a code division multiplexed digital data transmission system. There are two methods disclosed. The first calculates i and j values for storage in RAM as a function of the symbol index in the TDMA stream, the number of codes to be employed, the column space design parameter representing the number of columns in the array, i.e., symbol times, that could be adversely affected by burst noise, and a calculated total number of columns in the array. The result is an array in which no indices of two symbols within any column or between columns of the column space are closer together than a design parameter vertical distance.

Abstract: A method for allowing upstream channels having the same multiplexing type but different symbol rates or the same symbol rates but different multiplexing types to be transmitted on the same frequency band without interfering with each other. In particular, a method for allowing DOCSIS 1.0 TDMA only cable modems to coexist on a digital data delivery distributed system with advanced PHY TDMA or SCDMA mode cable modems without the need for modification of the DOCSIS 1.0 cable modems or the need for the DOCSIS 1.0 modems to transmit on a different frequency.