Abstract: A system and method for collecting, integrating, and distributing video, data, and telephony signals in a fiber optic communications network for transmission along a twisted copper pair to a customer location. The video, data, and telephony signals are received by a digital subscriber loop access multiplexer and are superimposed onto the twisted copper pair using a service area interface. The system and method enables a customer to receive video, data, and telephony communication data along a single twisted copper pair at relatively high data transfer rates. Additionally, since portions of the existing communication infrastructure are used the cost of implementation is reduced.

Abstract: The present invention is embodied in a method an apparatus for reducing the number of leased E1 lines needed to backhaul communication traffic in a satellite communication situation. The present invention receives and decompressed a satellite signal. A copy of the compressed signal is then encoded into the least significant bits (LSBs) of the decompressed signal. The decompressed signal having the embedded information may be routed to an international PSTN network over leased communications lines. However, the compressed information is extracted from the decompressed signal and sent across the E1 lines, thereby conserving communication bandwidth and reducing the number of leased lines required. After passing through the E1 lines the information is decompressed and connected to the international PSTN network. Alternatively, the decompressed signal having the embedded information may be distributed to local PSTN networks, which interpret decompressed signals.

Abstract: A data stream (DS) comprises a time multiplex of coded data (D) and control data (C). The data stream (DS) may be, for example, of the MPEG type representing a sequence of pictures. The coded data (D) is transcoded (T) so as to obtain transcoded data (DT) which differs in size from the coded data (D). The control data (C) is adapted for the transcoded data (DT) so as to obtain adapted control data (CA) which does not substantially differ in size from the control data (C). The transcoded data (DT) and the adapted control data (CA) are written into a transcoder output buffer (TOB) and read from the transcoder output buffer (TOB) so as to obtain a transcoded data stream (DST). This allows an efficient use of a transmission channel via which the transcoded data stream (DST) is to be transmitted and, consequently, it allows a satisfactory transcoding quality.

Abstract: The invention relates to a coding method of signalling information in a packet radio system and to a packet radio system, which comprises at least one base station and subscriber terminal, in which signals to be transmitted on a radio connection between the base station and the subscriber terminal form blocks, which comprise bursts consisting of symbols, the burst comprising a training sequence in which modulation information is included. The invention is characterized in that signalling information is coded together with the modulation information relating to the whole block into the training sequences of the block. Coding enables e.g. a higher data transmission rate because it is not necessary to reserve data bits for coding of uplink state flags, for example.

Abstract: A timing technique for a Quantization-Level-Sampling (QLS) modem puts timing information in a downstream pulsed signal transmitted from the public switched telephone network (PSTN) to the QLS modem. In response to this timing information, the QLS modem synchronizes to the network sampling clock in the PSTN. In particular, the pulsed signal includes data-bearing samples, which were provided by a far-end QLS modem, and at least one non-user-data-bearing (NUDB) sample in which the level of this NUDB sample periodically alternates. The QLS modem extracts timing information from this periodic alternating signal level to synchronize the QLS modem to the network sampling clock.

Abstract: A field apparatus which allows for migration from an analog signal transmission system to a field bus transmission system without a need to change the configuration of the field apparatus and performs a self diagnosis. The field apparatus includes a receiving unit which receives a field bus oriented signal from another apparatus connected to the transmission line, an analog signal transmitting unit which transmits a measured magnitude of a measurement object through the transmission line as an analog signal, a field bus signal transmitting unit which transmits a measured magnitude of a measurement object through the transmission line as a field bus oriented signal, and a switch which selects either the analog signal transmitting unit or the field bus signal transmitting unit which transmits an analog signal or a field bus oriented signal respectively through the transmission line.

Abstract: A radio based access network type Digital European Cordless Telecommunication DECT in which powerful and simply-built up network components, such as repeaters are an integral part. The device makes possible a signaling which makes digital decoding and adding a special capacity to the system unnecessary.

Abstract: A communication control apparatus, provided with an echo back comparison detecting unit (30) detecting something abnormal of communication data from itself or an abnormal state generated at a data line (4), by starting transmission of communication data from itself following a detection of a line state detecting unit (29), when the line state detecting unit (29) detects that transmission of communication data from another communication apparatus to a data line (4) is started in a transmission permissible section, and by taking in communication data at the data line (4) and by comparing it with communication data having been transmitted from itself, and further provided with a transmission mark generating unit (23) shortening a bit width of data indicating a start of communication data transmitted from itself, prevents an abnormal waveform from being transmitted to the data line (4) because accuracy of echo back comparison is improved and delay tolerance of the data line (4) is eased.

Abstract: A billing system for use in a chargeable program broadcasting is capable of reliably billing a subscriber for program reception while preventing unauthorized reception thereof. A receiving terminal includes a primary terminal 100 and a secondary terminal 150. The primary terminal 100 receives a compressed video signal and confirms by an error checker 113 thereof whether there is a transmission error and bills, by means of a billing device 114 thereof, the receiving subscriber on the basis of an error information and a program information, etc., separated from the video signal by a separation circuit 112. The compressed video data is time-axis multiplexed with a terminal identifying code and a key signal and transmitted to the secondary terminal 150. In the secondary terminal 150, a bill for the subscriber is confirmed by the terminal identifying code and the compressed data is decoded by a decoder circuit 166 thereof.

Abstract: A method of transmitting data to a plurality of receivers is provided wherein an identifier is assigned to each of the receivers that cannot be ascertained once assigned, a subset of receivers is selected to receive data, and an encrypted board identifier corresponding to each receiver of the subset is transmitted, wherein a receiver of the subset becomes enabled upon receipt of the encrypted board identifier and data is transmitted with an indication that the data is only for receivers that have been enabled.

Abstract: A method of communication between a master unit and a slave unit, including the steps of: sending at least a command byte from the master unit to the slave unit including data byte counter bits to be interpreted by the slave unit according to the following rule set; if said data byte counter bits belong to a first set, then said data byte counter bits contain information representing a number of associated data bytes, which is the expected number of data bytes; if said data byte counter bits belong to a second set, then said data byte counter bits contain information representing a number which must be decoded before the expected number of data bytes is obtained; receiving at least the command byte; interpreting the command byte; and receiving the number of data bytes required by the rule set.

Abstract: An auxiliary data signal is transported with a primary data signal by hiding the auxiliary data signal in the form of colored noise. The colored noise has a spectrum that simulates the spectrum of the primary data signal. By adjusting the gain of individual spread spectrum signal carrier(s) and the power of the colored noise, the auxiliary information stream(s) can be rendered at any desired level below or above an interference threshold in the primary data signal. The power of the colored noise is further compensated to account for a cross-correlation between the primary data signal and the auxiliary data signal to enhance the recovery of the auxiliary data at a decoder.

Abstract: Auxiliary data is transported in a primary data signal by hiding the data in the form of colored noise. The colored noise has a spectrum that simulates the spectrum of the primary data signal. The data to be transported is first converted to a spread spectrum signal. The primary data signal is analyzed to determine its spectral shape. The same spectral shape is imparted to the spread spectrum signal, which is then combined with the primary data signal for transmission. The spectral shaping can be performed using time domain modeling and synthesis such as linear predictive coding or by using subband coding techniques such as fast Fourier transforms. A plurality of different auxiliary information streams can be transported on the primary data signal. By adjusting the gain of individual spread spectrum signal carrier(s) and the power of the colored noise, the auxiliary information stream(s) can be rendered at a desired level at, below or above an interference threshold in the primary data signal.

Abstract: A signalling packet for a communication system has a reference signal to support time and frequency synchronization. The reference signal is modulated so that it varies with time according to a predetermined modulation law. The variation is with respect to both the I and Q channels. Because of the variation with time, receivers can synchronize in frequency and in time with a base station in a simplified manner. Doppler shift can be determined and compensated.

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 compound transmission system compounds signals from a LAN communication device and other communication devices without multiplex them. A first LAN communication device is connected to a second LAN communication device through two line pairs (10, 20). A first signal transmission device such as an exchanger (111) is connected to center taps of windings of transformers (50, 51) on the side of the line pairs to superpose a communication signal from the first signal transmission device on the LAN signal and separate a telephone communication signal from the LAN signal at the center taps. The transformers (50, 51) constitute a first superpose/separate circuit. A second signal transmission device such as an exchanger terminal (112) is connected to center taps of windings of transformers (60, 61) on the side of the line pairs to superpose a communication signal from the second signal transmission device on the LAN signal and separate the communication signal from the LAN signal at the center taps.

Abstract: A subchannel within a CDMA signal is provided together with a system for receiving and decoding this subchannel. A message is transmitted over the subchannel by applying a sequence of phase rotations to the user data. A single subchannel message can be transmitted during each 1.25 ms segment of user data, resulting in a transmission rates of up to 800 messages per second over the subchannel. Each message corresponds to a fixed sequence of phases, called a phase codeword, used to rotate the user data each time that message is sent. When only two phase codewords are used, the effective data rate for the subchannel is 800 bits per second, but higher data rates may be achieved by increasing the number of codewords used by the subchannel. The subchannel may be decoded by correlating the user data with each of the possible phase codewords.

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 first phase change is introduced to an analog signal based on a symbol specified by a data signal, where the symbol is one of a plurality of symbols in a symbol constellation. The analog signal is added to the data signal to form a combined signal which is transmitted over a communication channel that introduces a channel phase change to the analog and data signals. After transmission through the communication channel, the combined signal comprises a phase changed analog signal and a phase changed data signal. A received symbol is specified by the phase changed data signal, and a phase shift is introduced to the phase changed analog signal based on the identity of the received symbol.

Abstract: A method and system for controlling uplink power for signal transmission in a satellite communication system employing on-board demodulation and remodulation and having a plurality of user terminals that are linked by and that communicate with each other by way of a satellite relay system. A downlink error rate of the data in a downlink data stream is determined based on known data bits. An end-to-end error rate of the uplink data stream and the downlink data stream is determined. An error rate of the signal transmission is then determined based on the downlink error rate and the end-to-end error rate. The signal transmission is then controlled based on the error rate of the signal transmission.

Abstract: A method and an apparatus are disclosed for combining information from two sources and for separating the combined information after transmission over one physical channel. A mask which represents a specified piece of information such as a control command or logic state of an input is exclusively ORed with an encoded input signal, thereby inducing a violation of an error control code. At the receiving end of the system, each of a set of masks is exclusively ORed with the received data stream. One of the masks is the same as the mask initially combined with the encoded input signal. Accordingly, once that mask is combined with the received data stream and so indicated by the favorable outcome of an error control code check, the original encoded input as well as the specified piece of information are recreated and produced.

Abstract: Methods and apparatus for detecting the presence of a particular signal among all the channels of interest in a cellular or similar type system are disclosed. A first method detects CDPD signals, and a second method detects DQPSK signals used in digital control channels in accordance with the IS-136 standard. These methods include the steps of sampling a received signal in at least one channel to obtain a predetermined number of samples for the at least one channel; computing an error value for each sample; determining a minimum error value; determining a ratio of the minimum error value to a reference value; and making a decision as to whether the received signal is the prescribed signal on the basis of at least the ratio, wherein the decision is made by comparing the ratio to a threshold value.

Abstract: A network topology allowing distributed sensing, control and communication, comprising a power source and a plurality of line-Powered, Serially connected Intelligent Cells (PSICs) coupled to the power source and to each other via respective communication channels comprising at least two electrical conductors. Each of the PSICs is uniquely addressed, preferably "on the fly" in real time, and at least one payload element is coupled to one of the PSICs for operating in accordance with control logic embedded in or fed to the corresponding PSIC. The communication channels allow for data transfer between adjacent PSICs in either or both directions independent of a simultaneous communication between another pair of adjacent PSICs.

Abstract: A timing technique for a Quantization-Level-Sampling (QLS) modem puts timing information in a downstream pulsed signal transmitted from the public switched telephone network (PSTN) to the QLS modem. In response to this timing information, the QLS modem synchronizes to the network sampling clock in the PSTN. In particular, the pulsed signal includes data-bearing samples, which were provided by a far-end QLS modem, and at least one non-user-data-bearing (NUDB) sample in which the level of this NUDB sample periodically alternates. The QLS modem extracts timing information from this periodic alternating signal level to synchronize the QLS modem to the network sampling clock.

Abstract: Auxiliary data is transported in a conventional audio signal by hiding the data in the form of colored noise. The colored noise has a spectrum that simulates the spectrum of the primary audio signal. The data to be transported is first converted to a spread spectrum signal. The primary audio signal is analyzed to determine its spectral shape. The same spectral shape is imparted to the spread spectrum signal, which is then combined with the primary audio signal for transmission. The spectral shaping can be performed using time domain modeling and synthesis such as linear predictive coding or by using subband coding techniques such as fast Fourier transforms. A plurality of different auxiliary information streams can be transported on the audio signal. By adjusting the gain of individual spread spectrum signal carrier(s) and the power of the colored noise, the auxiliary information stream(s) can be rendered inaudible in the primary audio signal, or at any desired level below or above an audible threshold.

Abstract: Multiplex broadcast receiving method and receiver which can easily update the preset contents of classification information, such as a program type, in an RDS broadcasting. The RDS receiver is constituted by a memory control section for storing the classification information (PTY code) demodulated from RDS broadcast waves which are being received into a PTY memory; the PTY memory for storing the classification information; and a station selecting section for selecting a station of the multiplex broadcast waves regarding the classification information by reading out the classification information from the PTY memory. This enables the use of the classification information of the broadcasting station being received as it is, so that the user can store the favorite program type by a simple operation.

Abstract: In accordance with the operation of an operating section 14, a control section 12 performs a reception control operation and demodulates a signal passing through a band pass filter 7 for extracting a multiplex signal using a multiplex signal demodulating section 8 when receiving a broadcast signal. A block synchronization circuit 16 of a synchronization circuit 9 carries out block synchronization processing on the demodulated signal. When block synchronization is established, a synchronization determination signal is supplied to a detecting section DET and the detecting section DET determines that a broadcasting station whose radio waves are currently being received is a multiplex broadcasting station.

Abstract: A method and simultaneous voice/data transmission of signals through a single communications channel wherein the transmitted voice and data signal quality is greatly enhanced over current practice. A time-varying stream of coded voice and data signals is simultaneously transmitted and the sequence of transmitted data signals is determined only after receiving data signals for a predetermined period of time. The received signals are buffered and a received coded data signal sequence is compared to a predetermined plurality of permissible coded data signal sequences to correlate the received coded data signal sequence with the particular permissible coded signal sequence with which the data signal was coded prior to transmission. The correlated data signal sequence is then separated from the combined voice and data signal to recover the coded voice signal.

Abstract: A video signal is supplied from a digital VTR 1 and is encoded by an MPEG encoder 8. The encoded video signal is recorded as a compressed video signal in an HDD 9. A plurality of compressed video signals are recorded in the HDD 9 and addresses of the compressed video signals are stored in a controller 6. MPEG decoders 12 and 14 decode the compressed video signals which are read out from the HDD 9. After a video signal processing apparatus 3 executes an editing process on the decoded video signals, a synthesized video signal is supplied to a digital VTR 10 through a switch 7. The synthesized video signal recorded in the digital VTR 10 is supplied to the video signal processing apparatus 3 for further processing through a switch 13 without being decoded.

Abstract: A system for combining AM and FM transmissions. In-band, On-channel, FM Digital Audio Broadcast (IBOC FM-DAB) allows simultaneous transmission of DAB and FM over existing FM allocations without interfering with conventional analog FM signals. The utility of existing FM spectrum allocations is therefore enhanced.

Abstract: Apparatus and method are provided for adaptively modulating or combining a first signal with a second signal. A series of values of the first signal are taken and sequentially stored in a shift register. The maximum absolute value of the oldest N values (where N is an integer) stored in the shift register is then determined. Before, during or after that determination, the maximum absolute value of the remaining (newer) series of values of the shift register is also determined. The lesser of those two maximum absolute values is then determined. This lesser maximum absolute value is then multiplied by a gain factor representing the desired gain to produce a scale factor. The gain factor can be a preset constant, or can be based on the steady-state ratio of the power of the second signal to the power of the first signal. The second signal is then multiplied by the scale factor to produce a scaled signal.

Abstract: A transmission system includes a transmitter and a receiver and transmits a data signal with an analog passband signal through an analog transmission line. The data signal is transformed to a signal representing a descrete data signal point in a vector signal space. The transmitter includes a data signal point generation unit and a vector signal superimposing unit. The analog passband signal is transformed to a base band signal, and the base band signal is superimposed on the signal representing a descrete data signal point. A signal representing the superimposed data signal point is modulated and transmitted through the analog transmission line. The receiver includes a demodulator unit and a decision unit, wherein the data signal point is decided from the signal representing the superimposed data signal point, and the superimposed base band signal is extracted in a subtracter unit by subtracting the decided result from the signal representing the superimposed data signal point.

Abstract: A CPU enables an FM tuner, a tuning controller and an FM multiplex decoder, after which the CPU is disabled. The FM tuner, tuning controller and FM multiplex decoder receives frame data including emergency information transmitted from a broadcasting station. When a packet coincidence circuit determines that the received block is a specific block which may include emergency information, the FM multiplex decoder causes an emergency information determining circuit to determine if the associated packet contains emergency information. If this packet contains emergency information, the emergency information determining circuit sends an interrupt signal to the CPU to enable the CPU. The CPU then reproduces the emergency information in the received data and displays it on a display section.

Abstract: A novel code division multiple access (CDMA) system and apparatus is provided which permits a plurality of encoded modulated data messages to be transmitted simultaneously on the same channel in one frequency band as a composite CDMA signal. An identification signal is generated and spread by a spreading signal having a duty cycle less than fifty percent to produce a combined signal which is transmitted to a receiver having a tapped delay with a plurality of taps each of which produce a replica of the received combined signal delayed by an odd multiple of the duty cycle of the spreading signal. Each of the replica signals is multiplied by a predetermined weighted value to produce weighted delayed signals and a controller responsive to the received combined signal, is employed for controlling individual weighted delayed signals which are then combined to suppress the spreading signal leaving the identification signal.

Abstract: The object of the present invention is to provide a wireless modem that performs detection with high reliability even in the case of carrier detection by analogue level, and whereby a large decrease in power consumption in standby mode can be obtained. Control unit 80 controls synthesizer 100 during transmission mode so that it transmits from antenna 200 one or two or more unmodulated carriers that have not been subjected to spectrum dispersion, at the head of the transmission preamble signal; in addition it performs on/off control of the output transmission clock pulse and reception clock pulse of clock pulse generating control unit 90, and changeover control of transmission/reception switch 53. Control unit 80 outputs a carrier detection enable signal to level comparator 75. Controlling its operation. In standby mode, control unit 80 controls synthesizer 100 and IF unit 40 such that the received unmodulated carrier can be detected by level detector 60 and level comparator 75.

Abstract: A cellular telephone system having three or more cell sites with each cell site having a source of cellular communication signals and an RF transmitter and antenna for broadcasting the cellular communication signals. A direct sequence spread spectrum waveform carrying navigation signals is embedded in the cellular communication signals, including controlling the signal strength of the navigation signals so that the combined energy of the navigation signals from all cell sites at any location is at least a predetermined energy level below the energy level of the cellular communication signals. Each cell site includes timing for timing the operation of a GPS receiver.

Abstract: In multiplex serial data communication circuit network and method, a clock information is always output from a single transmission control apparatus having an oscillation source onto a single signal transmission line. Any one of the other transmission control apparatuses carries out a serial data transmission with the clock pulse signal superposed on the data to be transmitted via the single transmission line. In addition, any one of the transmission control apparatuses extracts the clock information from the clock information superposed data signals on the single transmission line and takes an operation timing within all transmission control apparatuses from the extracted clock pulse signal. Furthermore, a remote DC motor control system and method using the multiplex serial data communication circuit network described above are exemplified. Master station and slave stations in the DC motor control system can be integrated into each plurality of ICs.

Abstract: A multiplex broadcasting station selecting method which can execute a station selecting operation in group units is provided. A PTY code to be compared and a channel are set to one set of large classification information. The user sequentially calls out the PTY codes to be designated to one group and depresses the same channel key or the like each time the desired PTY code is called, thereby storing into memory the large classification information in which a plurality of PTY codes are made correspond to a same channel number. When executing a retrieving operation, the user depresses one operation key. The large classification information corresponding to the channel number is consequently selected and the group having a similar genre can be retrieved as set. The user can receive either one of or all of the broadcasting stations in the large classification information of the group.

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.