Plural Separate Transmitters Or Channels Patents (Class 455/103)
  • Publication number: 20040259508
    Abstract: A radio communication apparatus for transmitting and receiving modulation signals of a plurality of channels in the same frequency band via a plurality of antennas. A communication method is based on information on electric wave propagation environment corresponding to each antenna of the communication partner and transmission is performed by selecting a transmission method for transmitting modulation signals of channels in the same frequency band from a plurality of antennas or a transmission method for transmitting a modulation signal of one channel from one antenna. Thus, it is possible to multiplex a plurality of modulation signals so as to be transmitted and to demultiplex and demodulate the transmitted multiplexed modulation signals at a reception unit, thereby improving the data transmission rate.
    Type: Application
    Filed: February 17, 2004
    Publication date: December 23, 2004
    Inventors: Yutaka Murakami, Masayuki Orihashi, Akihiko Matsuoka
  • Publication number: 20040235433
    Abstract: The present invention relates to a method for determining transmit diversity order and branches for a transmitter having at least two transmit diversity branches. The transmit diversity branches for use are determined based on estimated channel properties of transmit diversity branches. A network element and a radio transmitter, where transmit diversity branches are determined using estimated channel properties, are also discussed.
    Type: Application
    Filed: December 11, 2003
    Publication date: November 25, 2004
    Applicant: Nokia Corporation
    Inventors: Klaus Hugl, Juha Laurila, Werner Weichselberger
  • Patent number: 6823177
    Abstract: A radio station including two antennas combined with respective first and second hybrid transmission polarization couplers is disclosed. Each antenna is arranged to generate two orthogonal electric field components in response to two respective quadrature radio signals from the corresponding polarization coupler. The station further includes at least one hybrid distribution coupler with a first output connected to a first input of the first polarization coupler and a second output connected to a first input of the second polarization coupler and at least one radio signal source delivering a radio signal to a first input of the distribution coupler.
    Type: Grant
    Filed: January 25, 1999
    Date of Patent: November 23, 2004
    Assignee: Nortel Matra Cellular
    Inventor: Thierry Lucidarme
  • Patent number: 6823196
    Abstract: There is provided a communication apparatus including a plurality of radio transmitter sections, which is capable of suppressing unnecessary radiowaves from being generated due to mutual modulation distortion without increasing the size and weight of the whole apparatus. When the communication apparatus receives a signal from a radio base station and it coincides with the ID of a station when one transmitter section is operative, it rejects a process for the incoming call request. Therefore, no transmission is made simultaneously by the different radio transmitter sections, and the quality of the radiowaves transmitted may be kept high.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: November 23, 2004
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Taizoh Itoh, Yoshitsugu Moriwaki, Yoshiro Nakano, Kenji Edo, Takashi Maemura, Kouji Tashima
  • Publication number: 20040229576
    Abstract: The input side and the output side of a first bandpass filter circuit BPF1a are magnetically coupled to each other in a jump-coupling manner by the first mutual inductance (L31a, L41a) for connection between an input port IN and the input side of the first bandpass filter circuit BPF1a and connection between an output port OUT and the output side of the bandpass filter circuit BPF1a. The input side and the output side of a second bandpass filter circuit BPF2a whose center frequency is higher than that of the first bandpass filter circuit BPF1a are magnetically coupled to each other in a jump-coupling manner by the second mutual inductance (L32a, L42a) for connection between the input side of the first bandpass filter circuit BPF1a and the input side of the second bandpass filter circuit BPF2a and connection between the output side of the first bandpass filter circuit BPF1a and the output side of the second bandpass filter circuit BPF2a.
    Type: Application
    Filed: May 13, 2004
    Publication date: November 18, 2004
    Inventor: Yoshihisa Amano
  • Publication number: 20040224648
    Abstract: Systems and methods for optimizing the efficiency of each of a plurality of power amplifiers that amplify a corresponding one of a plurality of radio frequency signals for transmission by a corresponding one of a plurality of antennas. Using transmit beamforming, the power of each amplified signal output by the power amplifiers may not be the same for all the power amplifiers, and may vary with changes in the communication channel between the transmitting device and receiving device. Each of the plurality of power amplifiers is controlled to operate with one or more operating parameters that optimize the efficiency for an output power level of corresponding ones of the radio frequency signals. By adjusting one or more operating parameters of each power amplifier according to changing requirements (e.g., the destination device and channel conditions), the efficiency of each power amplifier can be optimized.
    Type: Application
    Filed: June 14, 2004
    Publication date: November 11, 2004
    Inventors: Gary L. Sugar, Chandra Vaidyanathan, Sifen Luo
  • Publication number: 20040219892
    Abstract: Techniques to correct for phase and amplitude mismatches in a radio device in order to maintain channel symmetry when communicating with another device using MIMO radio communication techniques. Correction for the amplitude and phase mismatches among the plurality of transmitters and plurality of receivers of a device may be made at baseband using digital logic (such as in the modem) in the receiver path, the transmitter path or both paths of that device. In a device, amplitude and phase offsets are determined among the plurality of radio transmitter and radio receiver paths by measuring phase and amplitude responses when supplying a signal to a transmitter in a first antenna path of the device and coupling the radio signal from a first antenna to a second antenna path of that device where the signal is downconverted by a receiver associated with the second antenna path, and similarly coupling a signal from the second antenna path to the first antenna path.
    Type: Application
    Filed: June 2, 2004
    Publication date: November 4, 2004
    Inventors: Chandra Vaidyanathan, Gary L. Sugar
  • Patent number: 6810239
    Abstract: An automated transmit combiner monitoring system (100) for an RF radio transmitter system includes a transmitter (101) for providing a primary source of radio frequency (RF) energy and an isolator network (105,107) for isolating the output of the transmitter (101) from secondary sources of RF energy. A transmitter combiner junction (109) is used for enabling the transmitter (101) to provide RF energy to a single antenna (111) while a dummy load (113) is used for loading any unwanted RF energy from the transmitter (101) that is received from the isolator network (103,105). An RF detector (115) is then used for measuring RF energy from the dummy load and an alarm reporting device (119) then monitors the system to provide an alert based on RF energy measured outside a predetermined threshold.
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: October 26, 2004
    Assignee: Motorola, Inc.
    Inventor: Steven M. Riddle
  • Publication number: 20040209579
    Abstract: A system and method for vector wireless radio communication (multiple modes or signal streams) between a first communication device and a second communication device using radio frequency (RF) communication techniques. At each communication device, signals are received at a plurality of antennas representing a plurality of modes simultaneously transmitted by the other communication device, wherein each mode is a signal stream. A transmit matrix is computed from signals received at the plurality of antennas. The transmit matrix distributes a plurality of modes among a plurality of antenna paths each associated with a corresponding one of the plurality of antennas of the first communication device, and is applied to the plurality of modes to be simultaneously transmitted from the plurality of antennas of one communication device to the other communication device.
    Type: Application
    Filed: February 13, 2004
    Publication date: October 21, 2004
    Inventor: Chandra Vaidyanathan
  • Publication number: 20040209580
    Abstract: In one aspect, the invention is a method for allocating channels. The method includes determining a communication standard used by a message and determining available channels. The method also includes allocating a channel based on the available channels and the communication standard used by the message. The method may also include sending an instruction to use the channel.
    Type: Application
    Filed: November 17, 2003
    Publication date: October 21, 2004
    Inventors: Vanu Bose, John M. Chapin, Steve Muir, Jeffrey Steinheider, Victor Lum
  • Patent number: 6807402
    Abstract: A device for generating a radio frequency electrical signals, delivering at least two separate signals having different frequencies, in the form of signals delivered by different primary sources and amplified with a predetermined gain. The device comprises a combining circuit (3), combining the signals delivered by the primary sources (2), a single channel power amplifier (4) and a multi-channel selection and routing unit (5) with a parallel structure. Each channel delivers at the output an amplified signal (S) at a frequency (F) characteristic of one of the primary sources (2) and comprises a filter circuit (6) adjusted to be passing for one of the different characteristic frequencies (F) of the different primary sources (2), an impedance adaptation circuit (7) and a rejection circuit (8) for frequencies other than the passing frequency of the filter circuit (6) of the channel in question.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: October 19, 2004
    Assignee: Bruker Biospin SA
    Inventors: Michel Weiss, Jean-Max Tyburn, Christian Brevard, Laurent Martinache
  • Publication number: 20040198406
    Abstract: A mobile wireless terminal (MWT) includes multiple wireless modems. The multiple modems have their respective transmit outputs combined to produce an aggregate transmit output. The multiple modems can concurrently transmit data in a reverse link direction and receive data in a forward link direction. The MWT is constrained to operate under an aggregate transmit power limit. Each of the multiple modems has an individual transmit limit related to the aggregate transmit power limit. An MWT controller controls the total number of modems that transmit data at any given time, based on an average energy-per-transmitted bit, or alternatively, individual energy-per-transmitted bits of the modems.
    Type: Application
    Filed: October 29, 2002
    Publication date: October 7, 2004
    Inventors: Aziz Gholmieh, Douglas A. Gerecht, Francis M. Ngai, Jon J. Anderson, William R. Panton
  • Publication number: 20040192232
    Abstract: An interference canceller 200 and corresponding method thereof operates to reduce the level of an interfering signal and includes a circulator 202 comprising a transmitter port, a receiver port and an antenna port, a transmission line 210 comprising a first end coupled to the transmitter port and a second end for coupling to a signal source; and a circuit 216, having an input coupled to the receiver port 206 and an output coupled 220 to the transmission line, for providing a phase shifted version of a signal coupled to the input at the output, wherein an interfering signal at the antenna port is reverse coupled to the transmission line by the circulator and coupled to the input of the circuit so as to reduce an amplitude of the interfering signal at the second end 212 of the transmission line. The interference canceller concepts may advantageously be used in a single transmitter version or in a multiple transmitter version (FIG. 4).
    Type: Application
    Filed: March 31, 2003
    Publication date: September 30, 2004
    Applicant: MOTOROLA, INC.
    Inventors: Robert Szopko, Justin N. Annes, Gregory T. Nash
  • Patent number: 6799020
    Abstract: An improved method and apparatus for using parallel amplifiers to efficiently amplify an information signal are disclosed. The improved apparatus utilizes digital signal manipulation techniques in optimizing the phase of the upconverted input signals provided to each of the parallel amplifiers. The phase and amplitude of the input signals are adjusted such that the power measured at the output of a combiner is maximized as compared to the sum of the power of combiner input signals.
    Type: Grant
    Filed: July 20, 1999
    Date of Patent: September 28, 2004
    Assignee: Qualcomm Incorporated
    Inventors: Peter D. Heidmann, Joseph P. Burke
  • Publication number: 20040180633
    Abstract: The radio communication apparatus comprising an antenna, a transmitting circuit of outputting a transmitting signal in a first frequency band, a duplexer, connected to the antenna and having a single-phase input terminal and a balanced output terminal, of conveying the transmitting signal inputted to the single-phase input terminal to the antenna and outputting a receiving signal in a second frequency band different from the first frequency band received from the antenna substantially as a differential signal from the balanced output terminal, and a receiving circuit connected to the balanced output terminal and having a circuit in which a gain of a signal of a differential component is higher than that of a signal of an in-phase component, or a loss of the signal of the differential component is lower than that of the signal of the in-phase component.
    Type: Application
    Filed: December 17, 2003
    Publication date: September 16, 2004
    Inventors: Toshifumi Nakatani, Atsushi Yamamoto, Hisashi Adachi
  • Patent number: 6792255
    Abstract: A wireless communication apparatus according to the present invention is composed of a first section for carrying out wireless communication with a multichannel signal and a second section having a plurality of channel units each process a predetermined frequency signal as a channel signal. The wireless communication apparatus is arranged to have a plurality of variable attenuators each provided for corresponding one of the channel signals received from each channel unit of the second section, a combiner for combining outputs from the respective variable attenuators together and outputting the resultant combined signal to the first section, and a control unit for controlling the degree of attenuation of the individual variable attenuators according to the variation of the number of the channel signals.
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: September 14, 2004
    Assignee: Fujitsu Limited
    Inventors: Yasuhiro Shibuya, Koji Hirai, Hiroyuki Kiyanagi
  • Publication number: 20040157567
    Abstract: Techniques for predicting weights used for closed-loop transmit diversity. In a channel prediction scheme, channel gains for multiple transmit antennas are initially estimated (e.g., based on pilots received from these antennas) and used to derive predicted channel gains for a future time instant. The predicted channel gains are then used to derive predicted weights that are deemed to be “optimal” at the future time instant. Optimality may be determined based on one or more criteria, such as maximizing a received SNR for the received signals. In a weight prediction scheme, the channel gains for the multiple antennas are estimated and used to compute optimal weights for the current time instant. The current optimal weights are then used to predict the optimal weights at the future time instant. For both schemes, the prediction may be performed based on an adaptive filter (e.g., LMS or RLS filter) or a non-adaptive filter.
    Type: Application
    Filed: February 10, 2003
    Publication date: August 12, 2004
    Inventors: Jittra Jootar, Da-Shan Shiu, Parvathanathan Subrahmanya
  • Publication number: 20040157555
    Abstract: A wireless audio distribution system having a wireless transmitter, responsive to a plurality of audio input channels, for transmitting a encoded digital bitstream serially combining each of the audio input channel, the encoded digital bitstream further including control data disbursed therein, a receiver, responsive to the transmitted encoded digital bitstream, for decoding and demultiplexing the digital bitstream, a manual selector switch, connected to the receiver device for selecting one or more of the audio input channels to be reproduced, and a sound producing device for selectively reproducing the one or more selected audio channels in accordance with the control data.
    Type: Application
    Filed: October 22, 2003
    Publication date: August 12, 2004
    Inventors: Lawrence Richenstein, Michael A. Dauk, Robert J. Withoff
  • Patent number: 6771940
    Abstract: A multi-channel transmission system and method provide peak power smoothing without additional in-band interference. The system includes a multi-carrier waveform generator for reducing peak amplifier power required to transmit a digital multi-carrier waveform based on a plurality of digital carrier waveforms. A signal conversion system generates an analog multi-carrier waveform based on the digital multi-carrier waveform. The analog multi-carrier waveform has a center frequency and a desired gain over the original signal. A bandpass filter is coupled to the signal conversion system for restriction of the analog multi-carrier output waveform to a desired transmission bandwidth. The multi-carrier waveform generator has a nulling waveform generator coupled to a plurality of single carrier waveform modules for generating a digital nulling waveform based on the retrieved data. The nulling waveform reduces a peak power of the multi-carrier waveform and results in a reduced signal envelope.
    Type: Grant
    Filed: March 27, 2001
    Date of Patent: August 3, 2004
    Assignee: Northrop Grumman Corporation
    Inventor: Andrew D. Smith
  • Patent number: 6765929
    Abstract: An FM transmitter forms a Digital Audio Broadcasting (DAB) signal comprising a digital FM signal and an analog FM signal. The FM transmitter comprises an RF nonlinear amplifier coupled to a first antenna and an RF linear amplifier coupled to a second antenna. The RF non-linear amplifier and antenna transmit the analog FM signal. The RF linear amplifier and antenna transmit the digital FM signal. The FM transmitter controls the signal transmissions such that the transmitted analog FM signal and the transmitted digital FM signal are combined, or multiplexed, together in the channel itself (here, the atmosphere) to form the DAB signal.
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: July 20, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Robert Louis Cupo, E Anthony Hinds
  • Patent number: 6763195
    Abstract: A hybrid wireless optical and radio frequency (RF) communication link utilizes parallel free-space optical and RF paths for transmitting data and control and status information. The optical link provides the primary path for the data, and the RF link provides a concurrent or backup path for the network data, as well as a reliable and primary path for the control and status information. When atmospheric conditions degrade the optical link to the point at which optical data transmission fails, the hybrid communication link switches to the RF link to maintain availability of data communications. The switch may occur automatically, based on an assessment of the quality of the optical signal communicated through the optical path.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: July 13, 2004
    Assignee: LightPointe Communications, Inc.
    Inventors: Heinz Willebrand, Maha Achour
  • Publication number: 20040132494
    Abstract: This invention relates to a method for use in a communication system comprising at least one transmitter and at least one receiver, said at least one transmitter comprising a plurality of transmitting antennas, said method comprising the steps of transmitting from at least one but not all of said transmitting antennas a reference signal on a respective first channel; transmitting data from said transmitting antennas on respective second channels, wherein the second channels transmitted by said at least one but not all transmitting antennas are supported by the respective first channel and the second channels transmitted by the other of said transmitting antennas are supported by a reference signal provided in the respective second channel.
    Type: Application
    Filed: January 3, 2003
    Publication date: July 8, 2004
    Inventors: Olav Tirkkonen, Markku Kuusela, Yrjo Kaipainen
  • Publication number: 20040116078
    Abstract: An iterative multistage detection system and method for orthogonally multiplexing K channels onto a signal processing chain using N orthogonal sequences of length N. The K channels include a first set of N channels and a second set of M channels (the M channels being separate and distinct from the N channels), where K=N+M. In a first iteration, interference from the first set of N channels imparted on the second set of M channels is removed from the multiplexed signal, thereby enabling the symbol values associated with the second set of M channels to be reliably estimated. In a second iteration, interference from the second set of M channels imparted on the first set of N channels is removed from the first set of N channels, thereby enabling the symbol values associated with the first set of N channels to be reliably estimated.
    Type: Application
    Filed: August 28, 2003
    Publication date: June 17, 2004
    Inventors: Pieter van Rooyen, Danie van Wyk
  • Publication number: 20040116079
    Abstract: Disclosed is a method of selecting a transmission antenna in a radio communication system. The present invention includes the steps of transmitting data through a sequentially selected antenna and if error occurs in the transmitted data, retransmitting corresponding erroneous data. Therefore, present invention presumes what channel state of antennas is better based on the response signal (ACK or NACK) of the reception party and then transmits data through the presumed antenna, thereby enabling to improve transmission performance more.
    Type: Application
    Filed: October 30, 2003
    Publication date: June 17, 2004
    Applicant: LG Electronics Inc.
    Inventors: Min-Jung Kim, Seung-Hoon Hwang
  • Patent number: 6747565
    Abstract: A remote control signal from a remote controller (2) is received by one of remote control optical reception parts (4a to 4d), and the respective reception signals are decoded by decoders (11a to 11d). At this moment, the decoders (11a to 11d) extract an address code included in the reception signals received by the remote control optical reception parts (4a to 4d). Based on this address code, an effective-ineffective signal showing effectiveness or ineffectiveness of the decode signal is created. When the effective-ineffective signal shows effectiveness, a decoder selection part (12) adopts a decoder signal of the corresponding decoder.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: June 8, 2004
    Assignee: NEC Viewtechnology, Ltd.
    Inventor: Kazuo Mochizuki
  • Publication number: 20040102161
    Abstract: The wide bandwidth transceiver includes a receiver section, a transmitter section, and a local oscillation module. The receiver section includes a 1st receiver intermediate frequency (IF) stage, a receiver switch module, and a 2nd receiver IF stage. The 1st receiver IF stage is operably coupled to convert a 1st inbound radio frequency (RF) signal into a 1st inbound IF signal based on a 1st local oscillation of the local oscillation module. The receiver switch module passes either the 1st inbound IF signal or a 2nd inbound RF signal, which have similar carrier frequencies, to the 2nd receiver IF stage. The 2nd receiver IF stage receives the selected signal from the receiver switch module and based on a 2nd local oscillation converts the selected signal into a low intermediate frequency signal. The transmitter section includes a 1st transmitter intermediate frequency (IF) stage, a 2nd transmitter IF stage, a power amplifier and a transmitter switch module.
    Type: Application
    Filed: November 27, 2002
    Publication date: May 27, 2004
    Inventor: Ahmadreza Rofougaran
  • Patent number: 6741838
    Abstract: A transmission side device combines two independent transmission signals (S1, S2) together to produce two combined signals, i.e., a sum signal (S1+S2) and a difference signal (S1−S2), and transmits the produced signals over two radio wave propagation paths, respectively. After the sum signal and the difference signal are received by the reception side device, the sum signal and the difference signal, as received, are subjected to an AGC control operation and a complex-level multiplication operation with a weighting coefficient based on correlation control, and then separated into two, restored, independent signals.
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: May 25, 2004
    Assignee: NEC Corporation
    Inventor: Ichiro Tsujimoto
  • Publication number: 20040097201
    Abstract: An apparatus and method for improving the efficiency of a power amplifier operating on the basis of a signal of a large peak-to-average power ratio (PAR). A main amplification part detects envelope values of an input baseband signal, reduces a peak value of the envelope values of the baseband signal to generate a peak reduced signal, amplifies the generated peak reduced signal, and outputs a first amplified signal. An error correction amplification part amplifies an error signal indicating a difference between the baseband signal and the peak reduced signal, and outputs a second amplified signal. A summing part combines the first amplified signal from the main amplification part and the second amplified signal from the error correction amplification part, such that high amplification efficiency is produced and an amplified output signal with reduced spectral regrowth in which an error is corrected can be outputted.
    Type: Application
    Filed: November 18, 2003
    Publication date: May 20, 2004
    Inventor: Hyun-Su Yoon
  • Publication number: 20040087283
    Abstract: An electronic radio system multifunction slice (100) for a electronic radio system (400). The slice (100) includes an antenna interface (102), several multi-band transceivers (106-112), a processor (104), and an avionics interface (114). The antenna interface (102) couples to the antenna preconditioners of the aircraft. The processor (104) is coupled to the multi-band transceivers (106-112) and antenna interface (102), and controls the transceivers (106-112) and antenna interface (102) to provide signal and data processing for at least two independent radio function threads. The processor (104) is also coupled to the avionics interface (114), which connects to the avionics network of the aircraft. Each multifunction slice 100 provides a programmable multifunction radio.
    Type: Application
    Filed: June 25, 2003
    Publication date: May 6, 2004
    Inventors: Gregory O. Jones, Michael E. Campbell
  • Publication number: 20040087275
    Abstract: A composite beamforming technique is provided wherein a first communication device has a plurality of antennas and the second communication has a plurality of antennas. When the first communication device transmits to the second communication device, the transmit signal is multiplied by a transmit weight vector for transmission by each the plurality of antennas and the transmit signals are received by the plurality of antennas at the second communication device. The second communication device determines the best receive weight vector for the its antennas, and from that vector, derives a suitable transmit weight vector for transmission on the plurality of antennas back to the first communication device. Several techniques are provided to determine the optimum transmit weight vector and receive weight vector for communication between the first and second communication devices so that there is effectively joint or composite beamforming between the communication devices.
    Type: Application
    Filed: October 28, 2003
    Publication date: May 6, 2004
    Inventors: Gary L. Sugar, Chandra Vaidyanathan, Yohannes Tesfai
  • Publication number: 20040087284
    Abstract: A search and rescue beacon includes a main transmitter transmitting a Cospas-Sarsat signal at a main frequency and an auxiliary homing transmitter transmitting a homing signal at a homing frequency close to the main frequency. Advantageously both the Cospas-Sarsat signal and the homing signal are generated by a single synthesizer switching between a main Cospas-Sarsat burst transmission and a continuous homing frequency transmission of the homing signal. The Cospas-Sarsat signal is advantageously transmitted at a higher power than the homing signal. The single synthesizer may use a single amplifier chain. The single synthesizer and amplifier chain may use a single antenna.
    Type: Application
    Filed: June 30, 2003
    Publication date: May 6, 2004
    Inventor: William A. Street
  • Publication number: 20040087294
    Abstract: An improved receiving phased array communication system supplies oscillating waveform signals with different phase delays to downconverting mixers in the processing channels of the receiving phased array communication system to compensate for phase difference in the received signal over the antenna elements therein. Similarly, an improved transmitting phased array communication system supplies oscillating waveform signals with different phase delays to the upconverting mixers in the processing channels of the transmitting phased array communication system to introduce phase difference in the transmit signal for transmission over the antenna elements therein. The oscillating waveform signals with different phase delays are preferably derived from a local oscillator that generates a local oscillating signal, and a delay line network having a plurality of fixed delay lines arranged in a serial manner to introduce increasing fixed phase delays in the local oscillating signal.
    Type: Application
    Filed: November 4, 2002
    Publication date: May 6, 2004
    Applicant: TIA Mobile, Inc.
    Inventor: James June-Ming Wang
  • Patent number: 6731615
    Abstract: The invention relates in particular to a TDMA transmission system including transmitters synchronized to a single receiver, each of the transmitters being able to transmit to the receiver on a given carrier frequency bursts with lengths which are all multiples of that of a unit burst including a guard time, the unit bursts including at least one guard time and the receiver being adapted to receive simultaneously bursts from different transmitters. According to the invention, each transmitter includes means for inserting a filler sequence into each burst to be transmitted at each location of the burst that is likely to correspond to a guard time in a burst received simultaneously on a different carrier frequency. The invention reduces the harmful effects of interference if the time of reception of the guard time of a burst on a first carrier frequency corresponds to the time of reception of information symbols in another burst received simultaneously on another carrier frequency.
    Type: Grant
    Filed: April 18, 2000
    Date of Patent: May 4, 2004
    Assignee: Alcatel
    Inventors: Jacques Bousquet, Francois Durnez, Christophe Gerrier
  • Patent number: 6728309
    Abstract: Disclosed is an architecture and method for high speed transmission over a four-wire subscriber line. Each modem in the present invention includes a V.90 transmit section and a V.90 receive section. The V.90 transmit section is dedicated to transmitting data over one pair of a four-wire subscriber line, while the V.90 receive section is dedicated to receiving data over the other pair of the four-wire subscriber line. The present invention permits full-duplex transmission at 56 Kbps over a four-wire subscriber line.
    Type: Grant
    Filed: January 14, 2000
    Date of Patent: April 27, 2004
    Assignee: 3Com Corporation
    Inventor: Earl Turner
  • Patent number: 6728307
    Abstract: An adaptive transmit antenna array having a reduced pilot set is disclosed. The adaptive transmit antenna array utilizes a decision-directed mechanism for the estimation of maximal ratio combining (MRC) weights to be used at a receiver rather than requiring a user-specific pilot to provide estimation information.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: April 27, 2004
    Assignee: Nokia Mobile Phones Ltd
    Inventors: R. Thomas Derryberry, Balaji Raghothaman
  • Patent number: 6714525
    Abstract: A CDMA PCS telecommunications cell (40) of increased capacity includes a plurality of sectors (42, 44, 46) controlled by a base station (14) using a defined set of CDMA codes for each sector. Capacity is increased by configuring the base station to operate at two different, non-interfering frequencies within each sector of the cell.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: March 30, 2004
    Assignee: Sprint Communications Company, L.P.
    Inventor: Nagi A. Mansour
  • Publication number: 20040053583
    Abstract: A method for improving the use of a transmission spectrum in a multi-sector wireless communication system includes generating a first signal, processing a first signal with a first Auto Tune Combiner, transmitting the first signal on an antenna associated with a first sector, sampling the first signal with a radio frequency test device, generating a second signal, processing the second signal with a second Auto Tune Combiner, transmitting the second signal on an antenna associated with a second sector, and sampling the second signal with the radio frequency test device.
    Type: Application
    Filed: September 13, 2002
    Publication date: March 18, 2004
    Inventors: David Bogart, Richard Bruno, Martin Chang, Christopher Scott Erwin, Kraig Keys
  • Publication number: 20040048584
    Abstract: Techniques to correct for phase and amplitude mismatches in a radio device in order to maintain channel symmetry when communicating with another device using MIMO radio communication techniques. Correction for the amplitude and phase mismatches among the plurality of transmitters and plurality of receivers of a device may be made at baseband using digital logic (such as in the modem) in the receiver path, the transmitter path or both paths of that device. In a device, amplitude and phase offsets are determined among the plurality of radio transmitter and radio receiver paths by measuring phase and amplitude responses when supplying a signal to a transmitter in a first antenna path of the device and coupling the radio signal from a first antenna to a second antenna path of that device where the signal is downconverted by a receiver associated with the second antenna path, and similarly coupling a signal from the second antenna path to the first antenna path.
    Type: Application
    Filed: June 9, 2003
    Publication date: March 11, 2004
    Inventors: Chandra Vaidyanathan, Gary L. Sugar
  • Patent number: 6701135
    Abstract: A multi-carrier transmitter has combination means for receiving and combining a plurality of carriers including a first modulated carrier for transmission in a first channel and a second modulated carrier for transmission in a second channel, to create a multi-carrier signal. Power control means are arranged to individually vary the power of each of the plurality of carriers before combination.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: March 2, 2004
    Assignee: Nokia Corporation
    Inventors: Harri Posti, Juha Maatta, Andre Dekker
  • Patent number: 6696923
    Abstract: In a transponder application, at least one transponder and at least one interrogating reader, the reader has at least two receiving units so disposed, for instance at different distances, relatively to the transponder, that signals from the same are received at different levels by the receiving units. By combination, e.g. by subtraction, of the received signals, disturbing signals received at practically the same level are eliminated while the difference of useful transponder signals is available. This substantially improves system performance in transponder applications and allows to increase the operating distance between reader and transponder.
    Type: Grant
    Filed: March 7, 2001
    Date of Patent: February 24, 2004
    Assignee: Datamars SA
    Inventors: Takamasa Ishii, Peter Stegmaier, Jean-Marc Jobin
  • Publication number: 20040023621
    Abstract: A system, method and device for MIMO radio communication of multiple signals between a first device having N plurality of antennas and a second device having M plurality of antennas. At the first device, a vector s representing L signals [s1 . . . sL] to be transmitted is processed with a transmit matrix A to maximize capacity of the channel between the first device and the second device subject to a power constraint that the power emitted by each of the N antennas is less than or equal to a maximum power. The power constraint for each antenna may be the same for all antennas or specific or different for each antenna. For example, the power constraint for each antenna may be equal to a total maximum power emitted by all of the N antennas combined divided by N. The transmit matrix A distributes the L signals [s1 . . . sL] among the N plurality of antennas for simultaneous transmission to the second device.
    Type: Application
    Filed: July 25, 2003
    Publication date: February 5, 2004
    Inventors: Gary L. Sugar, Chandra Vaidyanathan
  • Publication number: 20040014435
    Abstract: A multi-band radio frequency (RF) receiving method in a mobile communication system having a reduced size and cost includes receiving RF wave signals for four or more non-overlapping bands, primarily filtering a first wide band including adjacent first and second bands and a second wide band including adjacent third and fourth bands from the received RF wave signals, low-noise amplifying the RF wave signals of the first and second wide bands, respectively, secondarily filtering a third wide band including adjacent second and third bands and a fourth wide band including first and fourth bands from the low-noise amplified RF wave signals of the first and second wide bands, generating two band RF wave signals to be simultaneously received, and frequency-down converting the two band RF wave signals generated in the secondary filtering step into two band intermediate frequency wave signals by means of first and second oscillation frequencies.
    Type: Application
    Filed: July 10, 2003
    Publication date: January 22, 2004
    Inventors: Sang-Hyun Woo, Seong-Soo Lee, Jong-Ae Park
  • Publication number: 20040014434
    Abstract: The invention relates to a method for shaping beams in a radio communication system. The first weighting vectors used for the beam shaping are chosen orthogonal to each other.
    Type: Application
    Filed: April 16, 2003
    Publication date: January 22, 2004
    Inventor: Martin Haardt
  • Publication number: 20040005869
    Abstract: A wireless transceiver includes a transmitter having a harmonic rejection mixer and an RF output phase-locked loop in a two step up-conversion architecture, and a direct conversion receiver. The transmitter includes a local oscillator for producing a signal at a multiple of an intermediate frequency, a quadrature modulator harmonic rejection mixer responsive to the signal at the multiple of the intermediate frequency for modulating in-phase and quadrature-phase base-band signals to produce an intermediate frequency signal, a filter responsive to the intermediate frequency signal for producing a filtered intermediate frequency signal, and an RF output offset phase-locked loop responsive to the filtered intermediate frequency signal and the signal at the multiple of the intermediate frequency for producing an RF transmission signal. The harmonic rejection mixer reduces filtering requirements to facilitate a high level of circuit integration.
    Type: Application
    Filed: January 24, 2003
    Publication date: January 8, 2004
    Applicant: QUALCOMM Incorporaton
    Inventors: Puay-Hoe Andrew See, James Jaffee, Steven Mollenkopf, Sandor Szabo
  • Publication number: 20030236076
    Abstract: The invention concerns a method for estimating a plurality of symbols transmitted by a first plurality (M) of transmit antennas at a given emission time or a plurality of symbols subjected to a space-time dispersion coding prior to transmission by said first plurality (M) of transmit antennas over a second plurality (L) of transmission times, the method using the signals received by a third plurality (N) of receive antennas, each symbol belonging to a modulation constellation, and comprising the steps of:
    Type: Application
    Filed: May 21, 2003
    Publication date: December 25, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventor: Loic Brunel
  • Patent number: 6662018
    Abstract: A power control system for a multi-carrier base station transmitter is capable of controlling power levels of individual RF carriers. The power control system has a multi-channel amplification system for converting a plurality of analog input signals into a plurality of amplified carrier signals. The amplification system also generates a plurality of reference signals corresponding to the amplified carrier signals. Furthermore, the amplification system generates a multi-carrier signal, where the multi-carrier signal includes a summation of the amplified carrier signals. A correlating power detection system is connected to the amplification system, where the correlating power detection system generates total power control signals based on the reference signals and the multi-carrier signal.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: December 9, 2003
    Assignee: Northrop Grumman Corporation
    Inventors: Mark Kintis, Donald R. Martin, Vincent C. Moretti
  • Patent number: 6658238
    Abstract: Transmitter systems in which an output signal is obtained by the summation of signals with predetermined discreet levels given by several amplification cells. Given a signal to be sent with an amplitude A and a phase &phgr;0, a control circuit determines (&agr;) a number of amplification cells sufficient to obtain slightly more than the value A with the phase &phgr;0 but to carry out a phase adjustment (&bgr;) such that at least two of the cells are phase-shifted, one in advance and the other delayed with respect to &phgr;0, so that the total sum of the signals delivered by the cells gives the signal A, &phgr;0. Such transmission may find particular application to amplification cell transmitters with discrete output levels.
    Type: Grant
    Filed: January 10, 2001
    Date of Patent: December 2, 2003
    Assignee: Thomson-CSF
    Inventors: François Ursenbach, Arnaud de Grammont
  • Patent number: 6650876
    Abstract: The present invention is related to a terrestrial cellular radio communication network comprising at least a first base station (BS1) in which a common set of multi carrier power amplifiers (409-412) are used to amplify radio signals transmitted by the first base station (BS1) in different cells. The invention enables reductions in the total maximum output power the first base station (BS1) needs to support when downlink power control functions, such as power control or discontinuous transmission, and/or Adaptive Channel Allocation are applied in the cells served by the first base station (BS1).
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: November 18, 2003
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Thomas Östman, Tomas Stolt, Ceylon Utterborn
  • Publication number: 20030203743
    Abstract: A MIMO radio transceiver to support processing of multiple signals for simultaneous transmission via corresponding ones of a plurality of antennas and to support receive processing of multiple signals detected by corresponding ones of the plurality of antennas. The radio transceiver provides, on a single semiconductor integrated circuit, a receiver circuit or path for each of a plurality of antennas and a transmit circuit or path for each of the plurality of antennas. Each receiver circuit downconverts the RF signal detected by its associated antenna to a baseband signal. Similarly, each transmit path upconverts a baseband signal to be transmitted by an assigned antenna.
    Type: Application
    Filed: October 11, 2002
    Publication date: October 30, 2003
    Applicant: Cognio, Inc.
    Inventors: Gary L. Sugar , Robert M. Masucci , David G. Rahn
  • Publication number: 20030203721
    Abstract: In one embodiment, a method for generating an adaptive air interface waveform includes generating a waveform that includes a variable carrier frequency and variable bandwidth signal. The variable bandwidth signal includes one or more subcarriers that are dynamically placeable over a range of frequencies, and each subcarrier is separately modulated according to a direct sequence (DS) spread spectrum (SS) technique. The waveform has an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform. A modulation constellation, a code rate, and a code length of the generated waveform are adapted according to an available spectrum and one or more sub-carrier conditions.
    Type: Application
    Filed: April 22, 2003
    Publication date: October 30, 2003
    Applicant: Raytheon Company
    Inventors: Roberto Berezdivin, Robert J. Breinig, Allan R. Topp, Scott Y. Seidel