Matches 151 - 200 out of 257 < 1 2 3 4 5 6 >
Match Document Document Title
5982819 Modulation format adaptive messaging receiver and method thereof  
A messaging receiver (400) and corresponding system (100b) and method adaptable to a plurality of modulation formats including; a processor (401) having flexible resources (404), preferably...
5956328 Spread spectrum communications system  
In a data transmission system, transmission data is modulated based on π/4-shift QPSK modulation according to two spreading code sequences which are generated according to a chip timing signal in...
5946292 Method and digital receiver for receiving orthogonal frequency-division multiplexed signals  
A digital receiver uses a local oscillator to down-convert an orthogonal frequency-division multiplexed signal that has been modulated by differential phase-shift keying, and performs further...
5898739 QPSK demodulator for obtaining phase by arithmetic operation  
A QPSK demodulator that is smaller in size and lower in cost by restricting a storage capacity needed for a TAN -1 ROM to a minimum. Values of I and Q channel base band signals obtained by...
5887023 Method and apparatus for a frequency hopping-spread spectrum communication system  
The spread spectrum communication system of the present invention is intended to equalize link capacity by taking deterioration of link quality so as to enable reliable communication which enhances...
5815497 Method of transmission by packets between a plurality of transmitters and at least one receiver and transmitter and receiver implementing this method  
The disclosure relates to the transmission of data by packets on carrier frequencies with spreading and de-spreading of the data elements. In order to reduce the risks of overlapping among packets...
5805567 Orthogonal modulation scheme  
The modulation scheme has two versions that can transform two data streams into two mutually orthogonal modulated signals within the same carrier-frequency band. In one embodiment, the modulation...
5729570 Orthogonal code division multiple access communication system having multicarrier modulation  
An orthogonal code division multiple access (OCDMA) communication system having multicarrier modulation. The incoming input data stream is broken into multiple parallel streams, each of which...
5706275 Data transmission method, transmitter, and receiver  
A receiver, and a data transmission method in a system wherein the CDMA multiple access method in a system wherein the CDMA multiple access method is utilized and wherein each data signal to be...
5537398 Apparatus for multi-rate simulcast communications  
A messaging system (500) for transmitting a message to a subscriber unit (312). The messaging system (500) includes a plurality of geographically distributed messaging transmitters (302-310), each...
5533004 Method for providing and selecting amongst multiple data rates in a time division multiplexed system  
In a Radio Frequency (RF) communication system using Time Division Multiple Access (TDMA) having time slots of a common duration, a quantity of information bits to be transmitted is provided. Based...
5420868 Suppression of brillouin scattering in lightwave transmission system  
Optical nonlinear effects, such as stimulated (Brillouin) scattering, cause disproportionate attenuation of transmitted optical signals and usually occurs only when the optical power exceeds a...
5396484 Diversity communication method of time-division, time-compressed multiplexing telephone signal for mobile communication system  
In a mobile communication system in which signals are temporally compressed into time slots of a frame structure, a composite signal such as a telephone signal or data signal is hybrid-modulated...
5314450 Dual channel telemetry for implanted medical device  
A method of and apparatus for telemetering both analog and digital data transcutaneously between an implantable medical device and an external receiver, such as between an external programmer and...
5126998 Method and apparatus for transmitting and receiving a carrier signal which is simultaneously frequency and phase modulated  
A method and apparatus for transmitting and receiving a carrier signal which is simultaneously frequency and phase modulated, including a carrier signal, a frequency modulator for imposing on the...
5079525 Audio-video modulator system on IC chip  
An RF modulator comprising an FM modulator supplied with an audio signal, and AM modulator supplied with the FM modulator output and a video signal, an oscillator for generating a sound subcarrier...
4962496 Transmission of data via power lines  
A method for transmitting data in the form of a sequence of data words according to PLBus communications protocol in a channel (20) carrying data transmitted, according to a different protocol, in...
4908819 Integrated data voice multiplexer supporting handshake and loop-back protocols  
An integrated data voice multiplexer (IDVM) capable of simultaneously supporting loop-back and communication handshake protocols with no performance degradation. This allows the IDVM to be used in...
4885737 Echo canceler having simplified calculation circuits  
Echo canceler associated with a modem utilizing amplitude and phase modulation of a carrier, the echo canceler comprising adaptive filters (16-1) to (16-p) producing signals which are combined in...
4882725 Multiplex transmission method and apparatus  
A multiplex transmission method using especially a vestigial-sideband amplitude-modulated carrier modulated by a video signal. The method includes modulating a carrier having a quadrature phase...
4864637 FMX stereophonic broadcast receiver  
An improved FMX sterophonic broadcast receiver provided with countermeasures against transient noises, which includes a level detection circuit for detecting level of a detected stereo difference...
4723237 Signal transmission arrangment, a transmitter and a receiver for such an arrangement and a communication system including such an arrangement  
A communication system comprises a plurality of subscriber stations (51-1 to 51-n) each of which comprise a transmitter (3) and a receiver (4). A switching network comprising a selection switch...
4719616 Communication method and apparatus  
A method of communicating data between first and second communication apparatus having the steps of transmitting line current from the first communication apparatus to a transmission line...
4680749 Duplex radio transceiver having improved data/tone and audio modulation architecture  
A novel circuit architecture is disclosed for achieving audio, tone, and digital data signal modulation in a full duplex radio transceiver. A single signal source is utilized to generate both...
4677608 Method of transferring an additional information channel across a transmission medium  
A method of transferring a service channel over a fibre optic system line is proposed. The system line normally transmits regular data signals with a specific highfrequency (34% Mbits), which are...
4660193 Digital modulation method for standard broadcast FM subcarrier  
A digital transmission system using standard FM broadcast stations employs an SCA subcarrier which is amplitude modulated with a second subcarrier modulated to have different phase orientations...
4660192 Simultaneous AM and FM transmitter and receiver  
A process and apparatus for simultaneously broadcasting a first intelligence signal with a plurality of second intelligence signals is disclosed. The transmitter performs the following steps:...
4642573 Phase locked loop circuit for demodulating suppressed carrier signals  
A phase locked loop circuit for use in a heterodyne receiver for stably demodulating a carrier-suppressed double-sideband signal such as a 2-phase or 4-phase PSK signal. The phase locked loop...
4630282 Frequency-hopping digital data link  
Ordinary digital data is reformed and time shifted such that it may be broadcast over a radio link which periodically shifts its frequency. The system of this invention utilizes timing information...
4584708 Communication system, and transmitter therefor, including special announcement recognition  
FM transmission system in which, besides program content, an auxiliary carrier of, for example 57 kHz, is radiated, which auxiliary carrier is modulated by an announcement recognition (AR) signal...
4525846 Modem in-band secondary channel via radial modulation  
A transmission system for transmitting a first data series, and a second data series from a first modem to a second modem using QAM or PSK type modulation techniques. The first data series is sent...
4521892 Direct conversion radio receiver for FM signals  
A radio receiver for FM signals having a demodulation system to produce an approximation to an analog output by either measuring the time intervals between successive zero crossings in the I.F....
4517562 FM Communication system  
Communication system for either public or private electric power load management and distribution automation, and the like, wherein subcarrier signals are sent to a plurality of remotely located...
4489411 Process and a circuit arrangement for signal transmission using an amplitude-modulated radio broadcasting system  
For the simplified text or picture data signal transmission through a broadcasting system, an additional phase and/or frequency modulation is produced in amplitude modulated transmitters. In a...
4477896 Single-wire data transmission system having bidirectional data synchronization, and D.C. power for remote units  
A communication system is described in which information may be simultaneously transmitted in both directions over a single common wire between a base unit and a plurality of remote units. The...
4476577 Radio transmitter system with special program identification  
To permit mass-production of coders selectively usable in various types of transmitter installations, and regardless of whether designed for stereophonic or monophonic transmission, in which a...
4438511 Packetized ensemble modem  
A high speed digital data modem particularly suited for use on a dial up telephone line is disclosed. For the transmit ensemble, the telephone passband is divided into sixty-four sub-bands each...
RE31510 Signal multiplexing circuit  
The disclosed signal multiplexing circuit (110) makes use of a single pair of wires (T, R) to interface a data and voice communication circuit such as an electronic key telephone (EKT) station set...
4410979 Multiplexed signal receiver  
A multiplexed signal receiver is arranged such that two independent signals are multiplexed on a single carrier by amplitude and frequency modulation or amplitude and or phase modulation. The...
4404532 Modulator having improved bandwidth and power requirements  
A modulator is disclosed for use with digitized multiplexed voice channels in which service bits are transmitted using QPSK modulation while the audio information is transmitted using amplitude and...
4402073 Speech and data communication network  
The network comprises a two-wire bus (coaxial cable) and a source of synchronizing pulses connected to the bus for marking off TDM cycles of about 125 us duration comprising a control slot and 8...
4387455 Apparatus and method for transmission of communications  
Apparatus for transmission of information in digital form comprising apparatus for providing a plurality of signals coded into a multiplicity of digital code elements in accordance with a first...
4381560 Multiplex transmitter apparatus  
Combined amplitude and phase modulation of a multiplexed serial data stream is employed to generate a composite signal for transmission to a receiver. The composite signal includes a prescribed...
4379947 System for transmitting data simultaneously with audio  
An FM broadcasting system is disclosed for transmitting a data signal simultaneously with an auxiliary audio program on the same subcarriers of an FM transmission channel. The main program is...
4361728 Multiplex signal receiver  
A superheterodyne type multiplex signal receiver for multiplex signal transmission systems for receiving two independent signals transmitted by amplitude modulation and angle modulation of single...
4322842 Broadcast system for distribution automation and remote metering  
The inventor discloses a bidirectional communication system for electric power load management and distribution automation application, and the like, wherein outgoing control signals to a plurality...
4310920 Single sideband AM-FM stereo modulation system  
Single sideband modulation system. A first single sideband of radio frequency is generated with first audio modulation on the lower side of an assigned frequency, the first single sideband...
4267591 QPSK Suppressed carrier with rotating reference phase  
A suppressed carrier signal is offset quadrature phase shift key modulated so the reference carrier phase is stepped 90° in the same direction in synchronism with sequential bits of a serial data...
4238849 Method of and system for transmitting two different messages on a carrier wave over a single transmission channel of predetermined bandwidth  
In a radio broadcoast channel, an additional message is superimposed on the normal message so as to be inaudible to the listener. To accomplish this, the additional message, consisting of digital...
4237486 Compatible transmission of an encoded signal with a television  
A method and apparatus of compatibly and simultaneously transmitting and receiving an encoded signal with the normal visual and aural carrier of a television signal is disclosed. The encoded signal...
Matches 151 - 200 out of 257 < 1 2 3 4 5 6 >