Abstract:
A system for providing interactive services in a subscription television system comprises a system network controller (28) for controlling the interactive services having controller memory for storing subscriber terminal identification data, transaction identification data and transaction return data, and a processor, coupled to the controller memory, for generating a transaction having interactive transaction data and transaction identification data. The processor also correlates received transaction return data with at least said transaction identification data and calculates summary data therefrom.
Abstract:
A packet of data, which contains a timestamp value and which is to be transmitted through an ATM network, is encapsulated in a convergence sublayer protocol data unit (92) having a header (96) and a payload (94). The CS-PDU is then segmented into successive segments (106, 108, 110 and 112) with one segment (106) containing the CS-PDU header (96). The segments (106, 108, 110 and 112) are inserted in respective ATM cells (114, 116, 118 and 120) and transmitted through the ATM network. At each node in the ATM network, any variable delays imposed on the cell (114) that contains CS-PDU header (96) are added to a time reference correction field (100) in the CS-PDU header (96). At a destination node, the accumulated delay value in the TRC field (100) of the CS-PDU header (96) can be added to the timestamp value of the packet to compensate for the variable delays imposed by the ATM network.
Abstract:
A flexible architecture for a digital data receiver including a demultiplexer (612) is provided which allows modular addition of data processors (630, 620, 618, 622) with low complexity and minimal memory requirements. The demultiplexer operates on a scalable frame-based multiplex signal, and interprets the multiplex control data at the start of the frame. With the information interpreted from the control data, the demultiplexer separates individual data services and optionally decrypts them. Data, a data clock and an error flag signal are presented to the demultiplexer input. According to a service requested by a user, the demultiplexer outputs decrypted data clock, error flag and service enable signals in a flow-through manner (610) to an appropriate data processor without data storage.
Abstract:
A multiplex frame format for transmitting digital data in a data transmission system comprises a PACKETS portion comprising a highly error-protected region, a region having only Reed Solomon encoding as an error protection measure, and a portion including low speed data. The frame format also comprises portions for transmitting medium (AUDIO) and high speed (VIDEO) data streams following the PACKETS portion. Prior to transmission, the composed frame comprising the PACKETS, AUDIO and VIDEO portions is interleaved and the BLOCK SYNC and FRAME SYNC are added (110). A multiplex structure control packet word of the PACKETS portion immediately follows FRAME SYNC. Thus, the FRAME SYNC word defines where interleaving begins. A demultiplexer (156) in concert with a microcontroller (158) of a decoder (154, 155) decodes the multiplex structure control word and related PACKETS and outputs digital data streams to related output peripheral processors (157).
Abstract:
A teletext system provides teletext services and teletext support services in a multiservice communication system. Multiplex data streams for a plurality of services, including teletex data, are transmitted in a sequence of frames between a transmitter location and a receiver location. Teletext information is transmitted in the format of a header packet and a data packet. The header packet contains information identifying the teletext information according to page number as well as other filter fields, such as language (filter 4), time zone (filter 2), etc. By appropriate selection of the values of the filter fields, the operator is afforded greater flexibility in providing a variety of classes of service and service support to subscribers. In addition, the system may easily be reconfigured to support the addition of services or the cancellation of services.
Abstract:
A transmitter site (100) with an encoder and a receiver site (150) are in the context of a satellite communication system. The transmitter site (100) includes: audio/video compressors (101(l) to 101(m)); low-speed data formatters (105(l) to 105(n)); a multiplexer (110); a control computer (120); a modulator/upconverter (130); and, an antenna (140). The signal from the transmitter site (100) goes through a satellite (160) to the receiver site (150). The receiver site (150) includes: an antenna (151); a tuner/demodulator (154); a clock-plus-data receiver (155); a demultiplexer (158); data processors (152); subscriber equipment (159); a display control processor (153); a digital compression in-board security element (157); and, a selector (156).
Abstract:
A digital video, audio and data distribution system which enables a set top terminal (STT) (30) associated with a customer's television set or the information presentation device to request interactive digital video, audio and data control system messages transmitted via a bi-directional signalling path. The requested interactive service is transmitted from the service provider over a portion of the banwidth of a broadband transmission network (128) which is dedicated to interactive digital services. A video Session Connection (VSC) is provided for setting up and maintaining interactive sessions between the set-top terminal and a video service provider during the time the interactive programming is provided to the customer. The set top terminal (30) and service provider (20) establish the Video Session Connection via a two way signalling path within the bandwidth of the transmission medium into the customer's home.
Abstract:
A plug (2) and socket (3) form a simple and compact electrical connector (1) for selectively distributing an electrical signal along different paths (21a, b, c). The plug (2) and socket (3) are symmetrically arranged so that they are engageable with each other in different positions to achieve different electrical connections. The electrical connector (1) saves printed circuit board space (19), minimizes parts, and improves switching flexibility in an RF signal amplification device (Figure 2) for amplifying an RF (e.g., CATV) signal transmitted along an RF cable (41), and in a power coupler (Figure 3) coupling an AC power signal (53) into an RF cable (41).
Abstract:
A display system for providing programmable on-screen displays for a subscriber terminal, includes a control processor (128) and a display processor (127) which generates such displays from stored display information and display attributes. The control processor (128) executes display routines to configure the display processor (127) and to load the display data into a display memory. The display routines, display attributes and display data are programmable and can be varied for optimal use of the display processor. In one implementation, such information can be modified by changing the programming in non-volatile memory of the subscriber terminal, either by switching ROM (134) or Flash EPROM ICs (326) or by a plug in module (138). Another implementation includes downloading the information with other executable code and data in the read/write portions of the non-volatile memory. A third implementation provides specialized display transactions for the information which, in a preferred embodiment, envisions a high level screen definition language whose commands can be compiled into the formats of the display routines, display attributes and display data.
Abstract:
An apparatus for providing close captioning or text insertion in a digital program service delivery system comprising: a rate converter circuit (130) for receiving video codes and outputting video data, a video decoder circuit (132) for receiving the video data and outputting digital component video data, a digital to analog converter/analog encoder circuit (148) for converting the component video data into an analog video signal in a prescribed format; a line former circuit (142) for receiving close captioning digital data and forming a line of analog signal; a multiplexor (150) for inserting the line of analog signal into the analog video signal.