Abstract: A system is presented having a graphical indicator in an interface screen of an electronic program guide. The graphical indicator is configured to focus a user's attention on a selectable program instance field. The indicator has a length that depends on the duration of the selectable program instance, thereby conveying the start and stop times of the selectable instance. At least one indicator attribute is controllable by the user. For example, the user may control the indicator height, weight, width or brightness.

Abstract: A rate controller in run-level domain transcoder, which receives a stream of compressed frames carried in a bit stream, selectively determines whether to quantize and/or threshold portions of a frame carried in the stream of frames. The rate controller determines the input size of the frame and based at least in part upon at least a desired size, requantizes and/or thresholds the frame such that the output size of the frame is approximately the desired size.

Abstract: A method of providing network access across a shared communications medium between competing users pursuant to SLAs of the users includes the steps of: (a) monitoring network access usage by each user during a time interval; (b) comparing the monitored network access usage by each user with a predetermined threshold value; and (c) soliciting a user to modify the user's SLA if the user's monitored network access usage varies from the predetermined value by a predetermined tolerance. The solicitation is conducted via email, instant messaging, redirection of a web browser of the user to a solicitation web page, generation and mailing of literature, telephonic communication, or other communication avenue.

Abstract: Systems and methods for dynamically allocating bandwidth in a digital broadband delivery system are disclosed. One example method includes receiving information describing subscriber requests for content delivery, receiving bandwidth allocation criteria, and processing the information describing subscriber requests and the bandwidth allocation criteria according to a statistical model. The bandwidth allocation criteria comprise at least one of subscriber pricing information, content delivery mode information, and program content information. The processing produces a bandwidth allocation schedule in which one of a plurality of content delivery modes is assigned to each of a plurality of digital transmission channels for each of a plurality of time periods.

Abstract: Systems and methods for training voice activation control of electronic equipment are disclosed. One example method includes receiving a selection corresponding to at least one command used to control the electronic equipment. The method further includes instructing a user to speak, and responsive to the instruction, receiving a digitized speech stream. The method further includes segmenting the speech stream into speech segments, storing at least one of the speech segments as an entry in a dictionary, and associating the dictionary entry with the selected command.

Abstract: In a subscriber television system with a host terminal, the present invention allows the identification of the individual packets from two separate MPEG transport streams that have been multiplexed together for decoding by a single external conditional access or point-of-deployment (POD) module. The decoding of individual packets from two separate MPEG transport streams supports the use of multiple tuner host terminals for such functions as picture-in-picture (PIP) program viewing and the viewing of one program while recording a second program.

Abstract: A cable television system (100) having forward and reverse paths includes, in the reverse path, a digital optical transmitter (200) for receiving an RF signal, converting it to a digital signal, and adding a digital pilot tone thereto. A laser is driven in accordance with the summed digital signal to generate a digital optical signal representative of the pilot tone and the RF signal. The cable television system (100) also includes an optical receiver (305) for receiving the digital optical signal and recovering therefrom the RF signal and the pilot tone. The optical transmitter (200) and receiver (305) are coupled by fiber optic communication media (110).

Abstract: An apparatus for providing close captioning in a digital program services delivery system comprises: a rate converter circuit for receiving video codes and outputting video data; a video decoder circuit for receiving the video data and outputting digital Y, U, V data; a digital to analog converter/analog encoder circuit for converting the Y, U, V data into an analog video signal in a prescribed format; a line 21 former circuit for receiving close captioning digital data and forming a line 21 analog signal; and a multiplexor for inserting the line 21 analog signal into the analog video signal.

Abstract: Vector quantization of a data vector proceeds through successive stages of a multi-stage vector quantization encoder until either (i) a measure of distortion between the vector input to a given stage and the codevector selected at that stage satisfies a threshold value or (ii) the last stage of the encoder is reached. The threshold value varies according to the fullness of a buffer which stores vector quantized data to be transmitted. Consequently, the last stage reached may differ from data vector to data vector. Compression efficiency therefore improves. Preferably, the mean value of each data vector is removed prior to vector quantization.

Abstract: A system and method for multiplexing a plurality of digital programs for transmission to a plurality of remote locations is claimed. An encoder is provided that first generates a plurality of subframe data streams each comprising a continuous sequence of subframes. Each subframe in each subframe data stream comprises at least a transport layer region and a program data region. For each subframe data stream, portions of the program data region of each of the subframes in that subframe data stream are allocated to selected ones of the plurality of programs. Mapping information is provided in the transport layer region of each subframe for use by a decoder in extracting a selected program from each subframe. A multiplex data stream is then generated at the encoder that comprises a continuous sequence of superframes. Each superframe comprises a superframe transport layer region and a subframe data region.

Abstract: Methods and apparatus for encoding compressed data streams efficiently, and methods and apparatus for decoding the encrypted data streams efficiently and inexpensively, are disclosed. In an encoder 10', an incoming data stream is fed to a Huffman coding block 10 that performs data compression. The output codewords of the Huffman coding block are fed to a forward error correction block 30, the output of which is a series of data blocks and associated parity data. The data blocks are fed to an error insertion block 32, which inserts a one-bit error in each data block. The parity data is fed to a first encryption block 34 that produces encrypted parity data. The output of the error insertion block 32, the encrypted parity data, and a synchronization word output by a sync generator 50 are fed to a multiplexer 48. A seed generator block 36 generates random numbers for use by the first encryption block 34 as seeds for encrypting the parity data.

Abstract: A link utilization control mechanism for a demand assignment satellite communication network employs a modified point-to-point communications protocol (X.25) in order to simulate point-to-point communication ports and thereby interface what is effectively a multidrop network with point-to-point landlink communication resources. Through an acknowledgement reservation mechanism the return link channel is subdivided into interleaved data and (preassigned) acknowledgement time slots, in order to substantially obviate overhead and throughput penalties encountered in the use of large data packets to transmit reduced size acknowledgement messages. In addition, the normal contention mode of operation of the return link is augmented with a data time slot reservation mechanism through which, during periods of increased message input density at a remote station, transmission throughput is facilitated, so that congestion at the remote station is reduced.

Abstract: A link utilization control mechanism for a demand assignment satellite communication network employs a modified point-to-point communications protocol (X.25) in order to simulate point-to-point communication ports and thereby interface what is effectively a multidrop network with point-to-point landlink communication resources. Through an acknowledgement reservation mecahsnism the return link channel is subdivided into interleaved data and (preassigned) acknowledgement time slots, in order to substantially obviate ovrhead and throughput penalties encountered in the use of large data packets to transmit reduced size acknowledgement messages. In addition, the normal contention mode of operation of the return link is augmented with a data time slot reservation mechanism through which, during periods of increased message input density at a remote station, transmission throughput is facilitated, so that congestion at the remote station is reduced.

Abstract: An apparatus and method is disclosed which phase locks a frequency-agile modulated output signal to any selected channel of a comb generated output. The phase error of an input signal is tracked, the input signal is modulated up to a carrier output frequency, and the modulated output frequency is locked to the comb generator output by subtracting the input signal and negating the phase error.

Abstract: Compensation for rain fades in a VSAT communications network is obtained by a uplink power control mechanism incorporated in a master station, which maintains the power output level of the satellite transponder constant without incorporating excessive static margins into the link power budget. A variable attenuator, which controls the output power of the master station's high power amplifier is initially set at a prescribed level which will produce the intended satellite amplifier EIRP for a `clear sky` condition. The master station monitors the output of the satellite amplifier and derives a measure of the signal-to-noise ratio of downlinked signals. Knowing the variable attenuator setting and the signal-to-noise ratio of the downlinked signals, the magnitude of attenuation of outlink carrier frequency signals transmitted from the master station to the satellite is determined.

Abstract: Accurate tuning of a satellite system's burst demodulator to a signal which is subject to frequency offset in the course of its transmission over the satellite link is achieved without the use of high precision oscillators at remote sites, or the transmission of a dedicated pilot tone. Instead, a dedicated high precision clock is used for the purpose of establishing both the outlink carrier and the return channel carrier. The modulation of the data on the outlink carrier is also derived from the precision clock source. At each remote station, the outlink channel is monitored to recover the high precision clock. This recovered clock is then used as a reference for generating the return channel carrier. The burst demodulator equipment at the master station monitors both the outlink channel continuous carrier and burst mode transmissions from the remote stations.

Abstract: Scrambling and descrambling systems utilizing jamming signals provide improved pictures with minimal distortion due to ghosts and artifacts. The television signal is combined with a jamming signal or signals located preferably in the vestigial sideband (VSB) of the modulated picture carrier and at about a null in the spectrum of the modulation of the picture carrier by the horizontal sync. The jamming signal or signals also preferably are placed between the harmonic components of the horizontal sync which define the horizontal sync spectrum and at frequencies which comply with governmental regulations respecting frequency locations of strong signals of CATV purposes. The jamming signals are generated by phase locking to the horizontal sync signals of the television signals or to a submultiple of the horizontal sync frequency.