Patents
Sitemap › H04 - Electric communication technique › H04L - Transmission of digital information, e.g. telegraphic communication › H04L 27 - Modulated-carrier systems
Patents for H04L 27 - Modulated-carrier systems (89,721)
01/1992
01/07/1992US5079512 Quadrature demodulation of a data sequence following a particular signal sequence with a local reference carrier signal having a frequency different from a received carrier signal
01/07/1992CA1294073C Tdma radio system employing bpsk synchronization for qpsk signals subject to random phase variation and multipath fading
01/02/1992EP0463625A2 Device operable with an excellent spectrum suppression
01/02/1992EP0463469A2 Interpolative digital-analogue converter for passband signals
01/02/1992DE4020192A1 Phase error compensation system for quadrature phase modulated carrier - uses correction signals obtained from control signals related to sum of sine and cosine of phase errors
01/02/1992DE4020191A1 Error compensation system for quadrature phase modulated carrier - uses control signals representing sine and cosine of phase error
01/02/1992DE4018911A1 Frame synchronisation procedure for phase keying and AM - recognising symbol position of sub-alphabet in symbol train by selection of signal alphabet lower quantities
12/1991
12/31/1991US5077757 System for synthesizing a modulated signal
12/31/1991US5077755 Digital signal processing system in modem
12/31/1991US5077542 Transmission system with suppressed carrier signal amplitude modulation preserving the polarity of the transmitted signal, and corresponding transmitter and receiver
12/31/1991US5077531 PSK signal demodulation system
12/31/1991CA1293778C Digital premodulation filter
12/27/1991EP0434689A4 Synchronous receiver for minimum shift keying transmission
12/26/1991WO1991020145A1 Signal acquisition
12/26/1991WO1991020142A1 Maximal ratio diversity combining technique
12/26/1991WO1991020140A1 Quadrature amplitude modulation synchronization method
12/24/1991CA1293534C Decision-directed control circuit
12/18/1991EP0461721A1 Transmitter comprising an electronic arrangement for generating a modulated carrier signal
12/18/1991EP0461720A1 Electronic arrangement for receiving a modulated carrier signal
12/18/1991EP0263845B1 Improvements relating to communication systems
12/17/1991US5073904 Digital signal processing type demodulation method and demodulation circuit
12/17/1991US5073903 Information transmission arrangement using frequency modulation
12/17/1991US5073901 Method for correcting waveform data in digital signal modulation and base band signal generator using data provided by this method
12/17/1991US5073331 Modulation method for use in a semiconductor laser and an apparatus therefor
12/13/1991WO1991020137A1 Communication signal having a time domain pilot component
12/12/1991WO1991019360A2 Method and apparatus for transmission of data over power lines
12/12/1991CA2084403A1 Method and apparatus for signalling
12/11/1991EP0461022A1 Apparatus for carrier recovery with means for preventing a false frequency lock
12/10/1991CA1293030C Qam demodulator with rapid resynchronization function
12/09/1991WO1991019362A1 Method and apparatus for mapping an eight dimensional constellation of a convolutionally coded communication system
12/04/1991EP0459968A1 Digital demodulator for multi-phase shift keyed signals
12/04/1991EP0459524A2 Error control coding arrangement for communication using convolutionally encoded QAM or PSK
12/04/1991EP0459339A1 Apparatus to measure the power, compensate the DC component and translate a GMSK signal to baseband
12/04/1991EP0459058A2 Inband coding of secondary data
12/04/1991CN1056787A Cable television radio frequency subscriber data transmission apparatus and calibration method
12/03/1991US5070516 Method and apparatus for reducing noise on a signal encodable on a plurality of predetermined levels
11/1991
11/30/1991CA2043353A1 Multi-state phase shift keying modulated signal digital demodulator
11/28/1991WO1991018455A1 A multilevel coherent optical system
11/27/1991EP0458695A1 Method for equalizing a received burst signal
11/27/1991EP0458385A2 Wholly digital process for the generation of multi-level modulation signals
11/27/1991EP0185758B1 A data frequency modulator with deviation control
11/26/1991US5068876 Phase shift angle detector
11/26/1991US5068875 Adaptive loop gain phase filter
11/26/1991US5068874 Spectrally efficient digital fm modulation system
11/26/1991US5068544 Fsk data waveform shaping circuit
11/26/1991CA1292525C2 Digital demodulation system
11/26/1991CA1292516C Time-varying trellis-coded modulation formats which are robust in channels with phase variations
11/22/1991WO1991018464A1 Hybrid modulation apparatus
11/21/1991EP0457602A2 Data security in multi-carrier communication systems
11/21/1991EP0457542A2 Transceiver with Doppler correction
11/19/1991WO1991018445A1 Frequency converter for a radio communications system
11/19/1991US5067141 Interpolator for varying a signal sampling rate
11/19/1991US5067140 Conversion of analog signal into i and q digital signals with enhanced image rejection
11/19/1991US5067139 Coherent detector for QPSK modulation in a TDMA system
11/19/1991US5067137 Adjacent channel interference canceller with means for minimizing intersymbol interference
11/19/1991US5066923 Linear transmitter training method and apparatus
11/19/1991US5066922 Stabilizing circuit for feedback RF amplifier
11/13/1991CN1056197A Multi-carrier high speed modem
11/12/1991US5065409 Fsk discriminator
11/12/1991US5065107 Phase-locked loop bandwidth switching demodulator for suppressed carrier signals
11/06/1991EP0455140A1 Apparatus for estimating frequency offset
11/06/1991EP0455089A1 Carrier recovery method for modulation with a large number of phase/amplitude states
11/06/1991EP0454913A1 Compensating for distortion in a communication channel
11/05/1991US5063574 Multi-frequency differentially encoded digital communication for high data rate transmission through unequalized channels
11/05/1991US5063387 Doppler frequency compensation circuit
11/05/1991US5063361 Serrodyne modulator
10/1991
10/31/1991WO1991016770A1 Data communication system
10/30/1991EP0454266A2 Receiver comprising a circuit for estimating frequency offset
10/30/1991EP0454021A1 Method for deactivating a resonant tag and circuit for carrying out this method
10/30/1991EP0453734A2 Modem comprising saw filters having opposite pass band delay characteristics
10/29/1991US5062155 Modulated light wave demodulator
10/29/1991US5062123 Kalman predictor for providing a relatively noise free indication of the phase of a carrier laden with noise
10/29/1991CA1291545C Data modem receiver
10/28/1991WO1991017606A1 Digital automatic gain control
10/24/1991DE4012265A1 Schaltungsanordnung fuer einen ausgangstankkreis einer mit frequenzumtastung betriebenen sender-endstufe Circuit arrangement for an output tank circuit powered by a frequency shift keying transmitter-power amplifier
10/23/1991EP0453203A2 Method and apparatus for correcting for clock and carrier frequency offset, and phase jitter in multicarrier modems
10/23/1991EP0400027A4 Method and apparatus for quadrature modulation
10/22/1991US5060088 Adaptive equalization for recording systems using partial-response signaling
10/22/1991CA1291280C Phase-coherent tdma quadrature receiver for multipath fading channels
10/18/1991WO1991016762A1 Circuit for an output resonant cavity in a frequency-shift transmitter output stage
10/17/1991WO1991015925A1 Transmission and reception in a hostile interference environment
10/17/1991WO1991015911A1 Communication system
10/17/1991WO1991015900A1 Trellis precoding for fractional bits/baud
10/17/1991CA2085728A1 Reception of orthogonal frequency division multiplexed signals
10/16/1991EP0451289A1 Digital demodulator
10/15/1991US5058136 Coherent detection for QPSK modulation
10/15/1991US5058135 Modulating arrangement for phase and amplitude modulation of a wave
10/15/1991US5058134 Process of synchronizing a receiving modem after a training on data
10/15/1991US5056235 Signal transmission system for machine tools, inspection machines, and the like
10/15/1991CA1290841C Electromagnetic identification system
10/09/1991EP0450476A2 Telemetry transmitter
10/09/1991EP0450148A2 Decoding circuit for inhibiting error propagation
10/09/1991EP0450001A1 Fully integrated digital fm discriminator
10/09/1991EP0344213A4 Viterbi decoder with reduced number of data move operations
10/09/1991EP0224556B1 Ensemble modem structure for imperfect transmission media
10/08/1991US5056122 Phase-shift keyed demodulation apparatus
10/08/1991US5056117 Decision feedback equalization with trellis coding
10/08/1991US5056115 Device for the division, at an optimum sampling rate, of a passband signal into its components on two carriers in quadrature
10/08/1991US5056112 Interleaving in coded modulation for mobile radio
10/08/1991US5056111 Integrated terahertz electromagnetic wave system
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