Abstract: In a two way cable system that includes a controller and a plurality of user terminals, a method of granting rights for upstream data transmission from the user terminals includes processing contention requests to generate contention grants and maintaining a list of connections, each connection having specified therefor a predetermined bit rate. The controller sends a downstream data stream to the user terminals and receives an upstream data stream from the user terminals. The downstream data stream includes a plurality of grant fields, and the upstream data stream includes upstream data slots and upstream control slots.

Abstract: A communication system (100) includes a tap (120) that has an input port (202) for receiving a signal and output ports (225) coupled to the input port (202) for providing the signal to subscriber equipment (125). Each of the output ports (225) has a programmed status comprising either an enabled status or a disabled status. After the statuses have been programmed and the output ports (225) have been set, a controller (210) coupled to the output ports (225) periodically restores the programmed status of the output ports (225) after programmed period of time, thereby automatically resetting inadvertent status changes.

Abstract: A terminal that facilitates efficient, flexible and user-friendly navigation of a plurality of program services provided by an associated television network. The terminal may be embodied in a home communication terminal (HCT) or other suitable device externally connected to a television or monitor, or as an integral component of a television or a computer. The terminal receives a user input identifying a user selected ordering scheme for the program services provided by the associated television system. The terminal either generates a display table or utilizes a previously generated display table, which in either case maps (i.e., orders) the program services as defined by a service table according to the selected ordering scheme for browsing by the subscriber. The ordering scheme is based upon at least one service attribute of the service information, such as the short description, long description, or service application associated with each program service.

Abstract: The present invention describes a method for transmitting reverse analog signals within a specific portion of a reverse band in an HFC communications system. Subscriber equipment (305) receives input defining the specific portion of the band for transmitting reverse analog signals. An optical transmitter (315) then converts the received reverse signals to digital reverse signals and transmits the digital reverse signals at a specified clock rate. Due to shifting of the digital reverse signals within the reverse bandwidth, shifting of the received digital signals reflect the specific bandwidth within which the reverse signals were originally transmitted.

Abstract: A subminiature time delay fuse device (300) that is capable of withstanding higher current ratings includes at least one time delay fuse (310) for receiving a power signal and for providing an open circuit when the power signal is determined to be excessive for a predetermined period of time. The subminiature time delay fuse device (300) has a high-temperature housing (320) that has a plurality of vent holes formed therein, and wherein the housing partially encloses at least one time delay fuse (310). There are two conductive terminals (305) with an upper end for mounting the time delay fuse (310) and a lower end for mating into a socket (235) on an electrical device, such as an amplifier (125).

Abstract: A cable television system (100) includes ahead end section (105) for processing information provided from subscriber equipment via a reverse path within the system (100). The reverse signal is provided from subscriber equipment in the form of a broadband RF signal, which can include voice, data, and/or video information. The broadband RF signal is provided from a plurality of subscribers to a node (200) that pulse width modulates the RF signal to generate a reverse optical signal. The pulse width modulated optical signal is then provided to the head end section (105) for processing to recover the information contained therein.

Abstract: A bypass switch (155) for use in an electronic device (125) includes a substrate (205) on which first, second, and third terminals (215, 220, 235) are mounted and an electrically conductive primary element (250), having first and second opposing ends, mounted to a bottom surface of the substrate (205) and electrically coupled to the first terminal (215) at its first end and to the second terminal (220) at its second end. The switch (155) also includes an electrically conductive bypass element (255), having first and second opposing ends, mounted to the bottom surface of the substrate (205) and electrically coupled to the third terminal (235) at its first end and vertically aligned, at its second end, with the second end of the primary element (250). A switch actuator (225) is mechanically coupled to the bypass element (255), extends through the substrate (205), and has an actuating surface (290) accessible at a top surface, opposite the bottom surface, of the substrate (205).

Abstract: A node (200) for receiving analog signals transmitted within a broadband communication system (100) includes a summer (205) for summing the analog signals to generate a summed analog signal and an analog-to-digital (A/D) converter (210) coupled to the summer (205) for converting the summed analog signal into a digital electrical signal. The node (200) also includes a digital signal processor (DSP) (220) coupled to the A/D converter (210) for filtering the digital electrical signal in accordance with a filter algorithm to generate a filtered digital signal. The DSP (220) including a control port for receiving a control signal (215) indicative of the filter algorithm that is to be used. The filtered signal is then transmitted upstream within the system (100) by a transmitter (240) coupled to the DSP (220).

Abstract: A cable television system (100) includes forward and reverse paths. In the reverse path, an optical transmitter (405), which could be located in an optical node (115), receives an analog information signal from subscriber equipment (130) and transmits in accordance therewith a digital optical signal. The optical transmitter (405) digitizes its incoming signal, compresses the signal, and generates therefrom the digital optical signal. The cable television system (100) also includes an optical receiver (500) for receiving the digital optical signal, decompressing information included in digital optical signal, and recovering therefrom an analog signal representative of the analog information signal. The optical receiver (500) could be included in a hub or headend equipment (105) of the cable television system (100).

Abstract: Techniques for determining an output rate for a bit stream, the output rate being determined by applying information read from the bit stream to a model of a receiver for the bit stream. The techniques are employed to construct a statistical multiplexer that multiplexes varying bit-rate MPEG-2 bit streams onto a satellite up-link. Minimum and maximum output rates for each MPEG-2 bit stream are determined such that neither a queue for the bit stream in the multiplexer nor the bit stream's decoder will underflow or overflow. The rates with regard to the decoder are determined using timing information read from the bit stream and a general model of an MPEG-2 decoder. The multiplexer first allocates each bit stream its minimum bandwidth and then allocates any remaining bandwidth to the bit streams in proportion to the difference between the minimum and maximum output rates for the bit streams, with no bit stream receiving more than its maximum output rate.

Abstract: A cable television system (400) includes a transmitter (200) for generating a digital optical signal and a receiver (201) for receiving such digital optical signal and converting it to an analog signal. The receiver (201) includes a digital filter (300) disposed between a deserializer (225) and a digital-to-analog converter (230), which digital filter conditions the digital electrical signal received from the deserializer (225). 1o The digital filter (300) is employed as a digital noise mitigation block so as to improve the quality of the signals in the reverse path, returning to the cable television system (400) headend (105).

Abstract: An electrical connector (305) with a conductive contact (420) that self-aligns via formed notches (425). The contact (420) also includes an opening (503) formed in a central region thereof for mating with a snap protrusion within an insulator (415) and flexibly holding it in place allowing the contact (420) to float within the insulator (415). The connector (305) additionally includes a plug that is inserted and retained into an aperture formed in the insulator (415). The connector (305) is rotated and electrically couples the contact (420) with the conductive member (310), thereby allowing alternating current (AC) power to flow through the connector (305).

Abstract: A cable television system provides conditional access to services. The cable television system includes a headend from which service “instances”, or programs, are broadcast and a plurality of set top units for receiving the instances and selectively decrypting the instances for display to system subscribers. The service instances are encrypted using public and/or private keys provided by service providers or central authorization agents. Keys used by the set tops for selective decryption may also be public or private in nature, and such keys may be reassigned at different times to provide a cable television system in which piracy concerns are minimized.

Abstract: A plastic housing for enclosing electronic circuitry that includes connectors for receiving and transmitting RF signals and power. The connectors include a center conductor and a shield, whereby a conductive liner within the plastic housing is connected to the shield of each connector. The conductive liner is capable of passing a minimum of 15 amperes of current through ground and also shields the enclosed electronic circuitry from EMI and RFI. Additionally, the plastic housing is capable of withstanding a significant amount of heat that is internally generated by the enclosed electronic circuitry.

Abstract: A broadband communication system (60), such as a cable television system, includes a forward path for transmitting information from headend equipment to subscribers and a reverse path for transmitting information from the subscribers to the headend equipment. The reverse path includes a transmitting station (65) that receives a first analog signal, converts the first analog signal to a first digital signal having a first number of bits, encodes the first digital signal to generate a second digital signal having a second number of bits less than the first number of bits, then optically transmits the second digital signal. A receiving station (70), also located in the reverse path, receives the second digital signal, decodes the second digital signal to generate a third digital signal having a third number of bits greater than the second number of bits, then converts the third digital signal to a second analog signal that approximates the first analog signal.

Abstract: Techniques for determining an output rate for a bit stream, the output rate being determined by applying information read from the bit stream to available bandwidths. The techniques are employed to construct a statistical multiplexer that multiplexes varying bit-rate bit streams onto a satellite up-link. Minimum and maximum output rates for each bit stream are determined such that neither a queue for the bit stream in the multiplexer nor the bit stream's decoder will underflow or overflow. The multiplexer looks at the fullness of the memory buffers and correlates the fullness with the likelihood of a condition in which output will exceed bandwidth. If there is not enough bandwidth to give every bit stream its minimum rate, glue frames may be inserted, or low priority channels dropped.