Abstract: A multicarrier transmission system (100) routes data symbols from a data source (142) to a multicarrier modulator (145). Each modulator (201, 202, 203) within the multicarrier modulator (145) is coupled to a corresponding gain adjuster (211, 212, 213) that distributes the available transmit power across various subcarriers. Power distribution, is determined in part, upon the noise sensitivity of the transmitted information. In accordance, data stream symbols of like sensitivity are grouped (520) and transmitted during defined time intervals. Each such group is assigned a unique transmission power level (530). At any given moment in time, all subcarrier transmission power levels will have an identical amplitude, thereby mitigating the impact of subchannel-to-subchannel interference.

Abstract: An apparatus and method is described for transmitting, receiving and communicating program data signals which are combined with digital data signals. Preferably, the present invention compresses 30 digital audio signals, multiplexes them with title, track, artist, record label, year, etc., program information, and transmits the combined signals via satellite to a receiving station. The receiving station demultiplexes the signals and sends them via a cable distribution system to a subscriber's digital music tuner. This tuner further demultiplexes and decodes the signals so that the digital audio signals may be converted to analog and output for listening, while the corresponding data signals are communicated to the subscriber. In an alternative preferred embodiment, the program data signals are transmitted to a remote control receiver where they are displayed. The system described in the present invention may be used for transmitting video, software or games with program data to subscribers.

Abstract: A swept frequency communication system includes a modulator that multiplies a frequency sweep signal with one or more underlying modulated communication signals to produce a swept frequency signal having a number of headerless tracks located directly adjacent one another in the swept frequency/time domain. A demodulator receives the swept frequency signal after that signal has been passed through a wireless channel, isolates a particular track of the received swept frequency signal to prevent a near/far problem, A/D converts the isolated track, resweeps the digitized isolated track, and then equalizes the isolated track using a blind channel equalizer to eliminate time-varying amplitude/phase impairments caused by transmission of that track through the wireless channel. The demodulator then removes the sweep signal from the equalized swept frequency track and decodes or demodulates the underlying modulated communication signal.

Abstract: A switching system for integratedly switching voice, data, image information and the like. The switching system comprises a plurality of front-end modules each adapted to perform a switching processing in association with a subscriber line or a trunk line, and a single or a plurality of central modules for interconnecting the plurality of front-end modules in star-type fashion and switching information prevailing between the front-end modules, in unit of block accommodating the information and a header added thereto to contain connection control information and in accordance with the contents of the header. The front-end modules are connected to the central module via inter-module highways each having frames occurring at a predetermined period and time slots contained in each frame to carry blocks.

Abstract: A system interconnect architecture and associated arbitration scheme that provides for the interleaving of multiple accesses to a shared system resource by multiple components on a data block by data block basis. According to one embodiment, an access request is granted "immediately" upon receipt such that the effective access latency between an access request and the transfer of a first data block (e.g. a byte. a word, a long word, and a double long word as determined by the width or throughput of the data path) for the access is the minimum access latency to the shared system resource. If a second access request is received while a first access is being performed, the second access request is granted immediately, and the first and second access are thereafter interleaved such that data blocks of the accesses are alternately transferred by the system interconnect.

Abstract: A method and apparatus is provided within a system having a total bandwidth divided into multiple segments. The segments are preferably frequency segments in a frequency division multiplexing environment or time slot segments in a time division multiplexing environment. The system transmits first downstream information from a head end to a router within a first bandwidth segment and transmits second downstream information from the head end to the router within a second bandwidth segment. The router sends the first downstream information to a first destination and sends the second downstream information to a second destination. First upstream information is transmitted from the first destination and through the router to the head end within a bandwidth segment used for downstream transmission other than the first bandwidth segment.

Abstract: A digital audio radio system that employs transmitting multiple time-separated versions or legs of the same or substantially the same source signal to accommodate signal blockage problems while using no or little additional bit data rate. In one embodiment, a first leg transmits only right channel data and a second leg transmits only left channel data when no blockage occurs, the two legs can be combined to provide a complete signal and perfect reception. If one of the legs is blocked, then a cloning technique is used to clone the existing channel as the non-existing channel to provide either a combination of two right channels or two left channels. In another embodiment, a first leg transmits a sequence of the even frames including both right and left channel data and leaves the odd frames blank, and a second leg transmits a sequence of the odd frames including both the right and left channel data and leaves the even frames blank.

Abstract: Apparatus provides time division multiplex (TDM) transmissions of interrupt requests between a plurality of shelves to a microprocessor mounted on one of the shelves. The shelves are interconnected with a cable wherein one lead is dedicated for the transmission of interrupt data signals to the microprocessor. Each shelf includes a plurality of ports or elements that are monitored and initiate interrupt request signals when a request for an action occurs therein for processing by the microcomputer. A separate encoder is mounted on each of the shelves for converting an interrupt request signal from an element on the same shelf into an X-bit interrupt data signal identifying that element. The bits of the X-bit interrupt data signal are serially transmitted over the one lead of the cable during a separate plurality of at least X clock cycles forming a timeslot assigned to the shelf originating the interrupt request within a frame period.

Abstract: A secondary packetized data stream, such as a commercial, is spliced with a primary packetized data stream, such as a network television program. The system does not require decompression of the data in the primary data stream, and is particularly suitable for use at a cable system headend to allow the insertion of commercials from local businesses into a nationally broadcast television program. When a start signal is received, a pre-splicing packet of the primary stream is determined. The pre-splicing packet is the packet closest to the start time which carries an anchor frame (e.g., I or P frame) start code. To prevent a potential discontinuity at the decoder, the pre-splicing packet is processed to discard the anchor frame data, and to insert a number of stuffing bytes which is equal to the number of bytes discarded into an adaptation field of the pre-splicing packet.

Abstract: A communications system is set forth comprising a plurality of remote receivers numbering M for receiving and demodulating respective PSK symbols received from a transmission medium. A central transmitter transmits periodically occurring frames of data to the plurality of receivers over the transmission medium. Each frame of data contains L total symbols including a subset of X.sub.m symbols designated for each one of the M plurality of remote receivers. The transmitter interleaves the X.sub.m symbols in a given frame into a plurality of periodic, non-consecutive groups of R symbols per group, wherein R<X.sub.m. In accordance with one embodiment of the invention, each of the remote receivers includes an equalizer implemented as a digital filter having N taps. In such instances, the transmitter interleaves the X.sub.m symbols in a given frame into a plurality of periodic, non-consecutive groups of R symbols per group, wherein R.ltoreq.N.

Abstract: A programmable data link module is used on a time division multiplex data bus. The module is functional as an input device, an output device, or both as an input or output device. It can receive data from the data bus during a selected time slot for selected number of frames to control output devices connected to it. The data link module includes an input circuit for generating a data output signal data to the data bus in response to input signals from in input device coupled to the module. The input circuit includes a programmable input communication mode selector, allowing the data bus and the data link module to function with or without a host computer. The mode selector provides simplex or duplex.

Abstract: A device for transferring binary data between a time-division multiplex and a RAM includes circuitry for assigning, for each time slot of the multiplex, a logical channel number. This enables two HDLC controllers, respectively for transmission and reception, to be shared between all the channels of the multiplex.

Abstract: A telecommunications system and method for minimizing interruptions to voice transmissions due to the transmission of overriding control signals is disclosed. Since FACCH and other control signals replace or block-out speech data, the quality of speech transmissions deteriorates the longer the control transmission. Through modifications to the FACCH protocol, lengthy sequential FACCH or other control transmissions are divided into a plurality of discrete control segments, which are transmitted non-sequentially throughout a speech transmission, and queued at the receiving end. After receipt of all of the control segments, the original control message is reconstructed and forwarded for processing.

Abstract: In a discrete multitone spread spectrum system, a base station receives a transmission burst from a remote unit being installed that includes delay compensation pilot tones that are uniformly spread throughout the transmission bandwidth. The arrival time transmission burst is not synchronized with the other remote units transmitting to the base station. The base station measures the phase delay of each tone and calculates the delay of the remote unit from the slope of the line of phase angle versus tone frequency. The base station transmits a signal to the remote unit that includes the magnitude and direction of the delay, which allows the remote unit to adapt the timing of its transmission to be synchronized with the other remote units.

Abstract: A method and device for communicating private application data, along with audio data (e.g., MPEG-2 encoded audio data) and video data (e.g., MPEG-2 encoded video data), from a first location to a second location. The private application data is either stuffed into a header portion of packets of encoded audio or video data, or packetized and multiplexed with packets of encoded audio or video data. The multiplexed packets form a packet stream which is communicated to the second location.

Abstract: An apparatus is disclosed consisting of one or more machine monitors which attach to one or more machines to sense a physical characteristic of the machine, such as vibration or temperature, and produce wireless transmissions corresponding to the sensed characteristic, and a command station which receives the transmissions from the machine monitors and processes the information to give an indication of the condition of the machine. The machine monitor incorporates a wireless transmitter to transmit the sensor data, and the command station incorporates a wireless receiver to receive the sensor data. In the preferred embodiment of the invention, the machine monitors are not continuously on, but turn on only at preprogrammed times according to turn-on commands generated by a timer circuit within each machine monitor. In another preferred embodiment, each machine monitor includes a receiver and the command station includes a transmitter to enable the command station to send commands to each machine monitor.

Abstract: A programmable data link module for use with a time division multiplex data bus includes an input and a high voltage protection circuit to prevent outputting of data to the data bus under several different operation conditions. These include programming of the data link module and verification of the programming. The data link module also inhibits the outputting of data signals to the data bus in response to changes of the input signals from a local input device until the power to the data link module has stabilized for a preselected period of time. The high voltage protection circuit protects the data link module from excessive overvoltage from other devices connected to the data bus.

Abstract: A video teleconferencing system uses digital transcoding to obtain algorithm transcoding, transmission rate matching, and spatial mixing. The video teleconferencing system comprises a multipoint control unit (MCU) for allowing multiple audiovisual terminals, which send and receive compressed digital data signals, to communicate with each other in a conference. The MCU has a video processing unit (VPU) that performs algorithm transcoding, rate matching, and spatial mixing among the terminals within a conference. The VPU includes a time division multiplex pixel bus and a plurality of processors. Each processor is assignable to an audiovisual terminal in the conference and is coupled to the pixel bus. In a receive mode, each processor receives and decodes compressed video signals from its assigned terminal and puts the decoded signal onto the pixel bus. In a transmit mode, each processor receives from the pixel bus uncompressed video signals from any terminal in the conference.

Abstract: In a subscriber loop equipment (10) having a subscriber bus (26), there is provided an odd data stream carrying a first set of data time slots of an E1 signal and a first set of signaling and control time slots of the E1 signal, and an even data stream carrying a second set of data time slots of the E1 signal and a second set of signaling and control time slots of the E1 signal. The odd and even data streams are bit-interleaved and transported on the subscriber bus (26).

Abstract: An apparatus for driving electrical loads provided at a vehicle by feeding power to the electrical loads, includes a power source for feeding power to a plurality of the electrical loads provided at a vehicle. The plurality of electrical loads are divided into more than one group. Each of the groups is driven by each of a plurality of load drive circuits by feeding power to each of the load drive circuits from the power source, provided at the vicinity of each of set places in the vehicle at which a group of the electrical loads are concentratedly arranged. A power line is connected to the battery, wherein each of the load drive circuits has a pair of power input terminals, and the power line connected to the battery is branched into two branch power wires. Each of the branch power wires is connected to a power input terminal of each of a first two load drive circuits of the load drive circuits.

Abstract: A communication system include a communication unit comprising first and second optical interfaces 2 and 3, a lower order interface 4, an active selecting circuit 5, and a spare selecting circuit 6. The active selecting circuit 5 include a selector 13 which selects one of transmission signals from the first optical interface and a selector 17 to supply the one of transmission signals to a active transmission path 10 of the lower order interface 4. The spare selecting circuit include a selector 15 and the selector 17. The selector 15 selects one of transmission signals from the first optical interface and the selector 17 to supply the one of transmission signals to a spare transmission path 11 of the lower order interface 4. The selector 17 is connected to input and output terminals 19 and 20 connected to each other. The selector 17 selects transmission signal from the first optical interface to supply the transmission signal to the selectors 13 and 15.

Abstract: An audio system has an attacher station for attaching to and decoding an audio representation channel, which also has a first auxiliary information sub-channel. A user station is fed by the attacher station through a unidirectional interface and receives the auxiliary information in an application context under control of a user interface for selective displaying. The attacher station extracts the auxiliary information from the channel. The system also has a framework data generator that is instantiatable by information from the information sub-channel, and a framework packetizer fed by the generator for supplementing the audio representation channel on said unidirectional interface in a second auxiliary information sub-channel by packetized and instantiated application information for the user station.

Abstract: A novel finite impulse response filter apparatus and method. A multiplexed data stream composed of two or more data streams is provided as an input to a tapped delay line. Weight and sum operators are connected to the even or odd delay line taps and generate a filtered output. The filter operates on one data stream per cycle and generates a multiplexed output. In another form, odd weight and sum operates are connected to and odd taps generating two filtered outputs. The filter operates on both data streams in each cycle and generates two multiplexed outputs. A crossbar switch is disclosed for parsing the multiplexed outputs into the constituent filtered data streams. The filter stages may be cascaded.

Abstract: This invention relates to methods and apparatus for extracting data of a channel from and for inserting low speed input data into a channel of time division bit multiplex. An optical data transmission system is used for distribution of video signals or information services. A variable frequency divider generates a timing signal by frequency dividing a clock signal by N. The resulting timing signal is phase shifted by M clock periods by inserting one cycle of 1/(N+M) frequency dividing in accordance with a synchronous command signal. With the timing signal, data of a channel is extracted from the time division multiplexed data of N channels by an extracting circuit, such as a D-type flip-flop. With a synchronous signal generated from the timing signal having the same pulse width of the multiplexed data, a low speed input data is inserted into a channel of the multiplexed data of N channels by a selector.

Abstract: A data multiplexing system which includes a plurality of data multiplexing buses through which a plurality of low-speed digital signals are collected into, and distributed from, a multiplexer/demultiplxer. In a data multiplexing mode, the low-speed digital signals entered from a plurality of low-speed transmission lines have their signal format converted by respectively corresponding low-speed interface circuits, and the resulting signals are multiplexed in time slots designated within a multiplexed signal of primary level on the up bus line of the corresponding data multiplexing bus. The high-speed multiplexer multiplexes the collected signals up to a predetermined signal level and sends the resulting secondary multiplexed signal to a high-speed interface module having a high-speed transmission line interface. The high-speed interface module converts the received secondary multiplexed signal and sends the resulting signal to the high-speed transmission line.

Abstract: In a system for transmitting information via a time-varying transmission channel, learning information is transmitted in addition to wanted information to enable the transmission channel to be estimated at the receiving end. The system estimates if it is necessary to transmit learning information given the current variations of the transmission channel and transmits learning information only if this is deemed necessary.

Abstract: In a mobile telephone set, a speech coder is provided for converting an analog speech signal to a digital speech signal. A voice activity sensor determining whether the analog speech signal is present or not. A storage level detector determines the amount of a data signal waiting for transmission from a non-telephonic communications apparatus. A switching control logic determines the rate for the speech coder according to the outputs of the voice activity sensor and the storage level detector. When the analog speech signal is present and the amount of the waiting data signal is zero, the data rate is set at a high rate and a digital speech signal from the speech coder is transmitted along with an indication of the high data rate.

Abstract: A switching system for integratedly switching voice, data, image information and the like. The switching system comprises a plurality of front-end modules each adapted to perform a switching processing in association with a subscriber line or a trunk line, and a single or a plurality of central modules for interconnecting the plurality of front-end modules in star-type fashion and switching information prevailing between the front-end modules, in unit of block accommodating the information and a header added thereto to contain connection control information and in accordance with the contents of the header. The front-end modules are connected to the central module via inter-module highways each having frames occurring at a predetermined period and time slots contained in each frame to carry blocks.

Abstract: A switching system for integratedly switching voice, data, image information and the like. The switching system comprises a plurality of front-end modules each adapted to perform a switching processing in association with a subscriber line or a trunk line, and a single or a plurality of central modules for interconnecting the plurality of front-end modules in star-type fashion and switching information prevailing between the front-end modules, in unit of block accommodating the information and a header added thereto to contain connection control information and in accordance with the contents of the header. The front-end modules are connected to the central module via inter-module highways each having frames occurring at a predetrmined period and time slots contained in each frame to carry blocks.

Abstract: An information transmission system includes a base station with a base transmitter and a plurality of satellite stations. Each satellite station includes a satellite receiver for receiving a transmission from the base station and a satellite transmitter including a transmitter amplifier, the transmitter amplifier requiring a preparation period of time to prepare the transmitter amplifier for operation. The transmission of information between and satellite station and the base station occurs during a transmission portion of a selected time slot within a succession of time slots. The amplifier in each of the satellite stations is prepared for transmission during a preparation portion of a same time slot having a duration at least equal to the preparation period for the satellite station transmitters and occurring prior to the transmission portion of the selected time slot.

Abstract: A dual priority switching apparatus for making input port to output port connections on a requested basis quickly and dynamically, in a standard mode from any one of the input ports to a fixed number of subsets of multiple output ports simultaneously, or in a broadcast mode from any one of the input ports to all output ports simultaneously. The apparatus permits multiple broadcasts to be queued at the individual switching apparatus which resolves the broadcast contention on a synchronous priority driven basis that permits one broadcast to follow the other at the earliest possible moment and the quickest possible speed. The apparatus permits multiple multi-cast operations to occur simultaneously within the network. The multi-cast function permits subsets of nodes assigned to the same tasks to communicate among themselves without involving other nodes that are not in its own subset. Hardware circuitry detects and corrects deadlock conditions in the multi-stage network.

Abstract: An apparatus and method is described for transmitting, receiving and communicating program data signals which are combined with digital data signals. Preferably, the present invention compresses 30 digital audio signals, multiplexes them with title, track, artist, record label, year, etc., program information, and transmits the combined signals via satellite to a receiving station. The receiving station demultiplexes the signals and sends them via a cable distribution system to a subscriber's digital music tuner. This tuner further demultiplexes and decodes the signals so that the digital audio signals may be converted to analog and output for listening, while the corresponding data signals are communicated to the subscriber. In an alternative preferred embodiment, the program data signals are transmitted to a remote control receiver where they are displayed. The system described in the present invention may be used for transmitting video, software or games with program data to subscribers.

Abstract: A method of transmitting real time digital video, audio and composite signals along existing delivery circuit and transmission pathways that takes advantage of unused bandwidth in existing transmission spectrums and circuit pathways. The invention permits the delivery of messages, commands and data files which may be presented later to the consumer at a predefined time and place and in a predefined format allowing the transmission of CD quality digital sound, digital video and bitmap files to a consumer, group of consumers or consumer population. The method and apparatus described transmits information and data to the consumer in a non real-time background mode which may be stored in a local repository for future presentation. Presentation parameters are transmitted either concurrently with or subsequently to information and data. The method may be employed on a wide variety of platforms including television, cable, satellite, telephone networks, private and public data networks and dedicated lines.

Abstract: A serial bit stream is first connected to two parallel bit streams using two half rate clocks. The 2-way parallel bit stream is then converted into a five-way parallel bit stream. Therefore, the clock rate of the five-way parallel bit stream is 1/5 of the clock rate of the input bit stream. The input bit stream contains a unique bit sequence or comma to identify the byte and word boundaries. The comma is detected in five way bit stream. Since the clock rate at the five-way bit stream is five times slower than at the input bit stream, substantially slower circuits which operate at lower power can be used to detect the byte boundaries. Therefore, substantially less expensive circuits can be used to adjust the byte boundaries. Quarter rate clocks in combination with two port latches can provide the same bit rate as half-rate clocks, but reduce the lifetime of CMOS circuits substantially less.

Abstract: A recording/reproducing apparatus for a data packet stream having an extractor for extracting data packets of a selected type from an input packet train in which different types of data packets have been time-division multiplexed together. The apparatus also has a recording circuit for recording the extracted data packets, and a reproducing circuit for reproducing the recorded extracted data packets. A dummy packet producer, which produces dummy packets that correspond to data packets that have not been extracted, is also provided. Further, the apparatus has an output circuit that outputs an output data packet train. The output data packet train is produced by combining the reproduced extracted data packets and the dummy packets in accordance with the order in which the different types of data packets are positioned within the input packet train.

Abstract: A method and apparatus for single signal, multiple channel digital information transfer through waves with time slot allocation. The apparatus consists of one or more transmitting devices and one or more receiving devices. Multiple source signals are each allocated a unique time slot between successive synchronization waves. Digital signals from each source are converted to analog information waves having a positive wave segment and a negative wave segment. The ratio of the amplitude of the positive wave segment to the amplitude of the negative wave segment, the positive-to-negative ratio, for each signal source, is a function of the magnitude of the source digital. The sum of the amplitude of the positive wave segment and the absolute value of the amplitude of the negative wave segment, the positive-to-negative offset, is maintained at a pre-set value at transmission.

Abstract: In a communication system, isochronous data can be continuously received without any interruption, and also asynchronous data irregularly transmitted can be received in a signal receiving apparatus. The signal receiving apparatus is arranged by comprising isochronous data being regularly transmitted; asynchronous data being irregularly transmitted; a common bus for transferring the isochronous data and the asynchronous data thereon; and temporary storage means for writing therein the received isochronous data and the received asynchronous data, respectively.

Abstract: In order to automatically renew data using a modem which can simultaneously transmit/receive audio and data signal, there is disclosed an apparatus having a modem which can simultaneously transmit/receive audio and data signal (4 in FIG. 2), a discrimination circuit (flow chart in FIG. 5B) for discriminating if a communication partner is a specific partner, and a control CPU (flow charts in FIGS. 4A and 4B) for controlling the modem to perform a predetermined data communication together with an audio call on the basis of the discrimination result of the discrimination circuit.

Abstract: A communication unit (103) transmits a concurrent monitoring request to a base station (102). Responsive to the concurrent monitoring request, the base station provides multiple communications from at least one dispatch position (101) and at least one other communication unit (104) to the communication unit. Upon reception of the multiple communications, the communication unit simultaneously renders the multiple communications audible, allowing an operator of the communication unit to concurrently monitor the multiple communications.