Phase Shift Keying Patents (Class 375/308)
  • Publication number: 20100061403
    Abstract: A method includes appending a preamble to a data packet and transmitting the preamble and data packet over a communication channel in the network. The preamble may be a Beacon, Admission, Broadcast, or High-Throughput Preamble. The Beacon Preamble includes the following symbols SS, SS, SS, SS, SS, SS, SS, SS, SS, SS, SS, SS, LS1, LS1, LS1, LS1, LS1, LS1, LS1, LS1, CP0, CEBeacon, CEBeacon. The Admission Preamble includes the following symbols SS, SS, SS, SS, SS, SS, SS, SS, SS, SS, SS, SS, LS1, LS1, LS1, LS1, LS1, LS1, LS1, LS1, CP0, CE, CE. The Broadcast Preamble includes the following symbols LS1, LS1, LS1, LS1, CP0, CE, CE. The high-throughput preamble includes the following symbols CP0, CE. The SS symbol includes 64 bits, the LS1, LS2, and CP0 symbols include 192 bits, the CE symbol includes 512 bits, and the CEBeacon symbol is a subset of CE.
    Type: Application
    Filed: September 10, 2009
    Publication date: March 11, 2010
    Applicant: ENTROPIC COMMUNICATIONS, INC.
    Inventor: Arndt MUELLER
  • Patent number: 7671692
    Abstract: The present invention relates to an apparatus and a method for compensating carrier feedthrough in a quadrature modulation system. In order to suppress the carrier feedthrough, and minimize and compensate the carrier feedthrough, differences of baseband differential input DC voltages in an in-phase as well as a quadrature-phase are simultaneously adjusted to 0 or a certain slight voltage difference by a simple analog circuit. Therefore, it is possible to suppress carrier feedthrough using a simple analog type apparatus for compensating carrier feedthrough, and simply achieve an apparatus for carrier feedthrough using a variety of quadrature modulators.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: March 2, 2010
    Assignees: Electronics and Telecommunications Research Institute, Samsung Electronics Co., Ltd.
    Inventors: Heon Kook Kwon, Joon Hyung Kim, Byung Su Kang, Kwang Chun Lee
  • Publication number: 20100046603
    Abstract: The invention describes a method and apparatus for transmitting data using a convolutional code used with a combination of Pulse Position Modulation and Binary Phase Shift Keying which has error rate performance that is as good as the best convolutional code when used with the more common binary phase shift keying (BPSK).
    Type: Application
    Filed: November 3, 2009
    Publication date: February 25, 2010
    Inventor: Michael McLaughlin
  • Publication number: 20100040010
    Abstract: An apparatus and method for transmitting and receiving information through a fast feedback channel in a broadband wireless communications system are provided. The apparatus includes a generator for generating a quasi-orthogonal signal stream corresponding to a codeword to be fed back, a plurality of mappers for mapping the quasi-orthogonal signal stream to a plurality of bundles in the fast feedback channel by using different mapping patterns, and a transmitter for transmitting the quasi-orthogonal signal stream mapped to the plurality of bundles.
    Type: Application
    Filed: August 13, 2009
    Publication date: February 18, 2010
    Applicant: SAMSUNG ELECTRONICS CO. LTD.
    Inventors: Hwa-Sun YOU, Hee-Won KANG, Jae-Hee CHO, Sang-Heon KIM
  • Publication number: 20100034316
    Abstract: Millimeter wave radio with phase modulation. In preferred embodiments each of the two radios in a link uses a single aperture to transmit radiation in one of the two bands, and receive radiation in the other of the bands. The counterpart radio used to form a link preferably is almost identical, except for the interchange of the transmit and receive frequencies. Preferred embodiments utilize a modulation scheme in which the radios each receive on-off keyed data and transmit the on-off keyed data encoded in a millimeter wave carrier wave with binary phase shift keying.
    Type: Application
    Filed: August 7, 2008
    Publication date: February 11, 2010
    Inventor: Eric Korevaar
  • Publication number: 20100027706
    Abstract: A signal transmitter apparatus generates three phase-shifted signals by shifting three transmission signals by predetermined phase shift amounts so that the phase shift amounts of the transmission signals are different from each other by 120 degrees. The signal transmitter apparatus generates three combined transmission signals and outputs the three combined transmission signals to the three transmission conductors, respectively, by combining each of pairs of the phase-shifted signals such that an inverted signal of a first phase-shifted signal is combined with a second phase-shifted signal, when each of the pairs of the phase-shifted signals includes the first and second phase-shifted signals among the three phase-shifted signals and phase shift amounts of the first and second phase-shifted signals are different from each other by 120 degrees.
    Type: Application
    Filed: October 3, 2007
    Publication date: February 4, 2010
    Inventors: Shin-ichi Tanimoto, Seiji Hamada, Hirotsugu Fusayasu, Ryo Matsubara
  • Patent number: 7656966
    Abstract: This invention provides a receiver for use in a SDAR system which includes a receiving unit having satellite signal detection means for detecting a first transmit signal transmitted from a first communication satellite and a second transmit signal transmitted from a second communication satellite, the first transmit signal produced when the transmitter modulates a primary data stream with a secondary data stream on a first carrier wave associated with the first communication satellite and the second transmit signal produced when the transmitter modulates the primary and secondary data streams on a second carrier wave associated with the second communication satellite, and an encoder re-encodes the primary and the secondary data on a third carrier wave, forming a third transmit signal which is re-transmitted to a receiver using a terrestrial repeater. This invention also provides a method of receiving transmitted data.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: February 2, 2010
    Assignee: Delphi Technologies, Inc.
    Inventors: Glenn A. Walker, Eric A. Dibiaso, Michael L. Hiatt, Jr.
  • Patent number: 7653349
    Abstract: A method and apparatus for adaptively transmitting an uplink signal comprising information from a ground station to a satellite is disclosed. The method comprises the steps of receiving a transmitted downlink signal at a ground station from the satellite; measuring the quality of the transmitted signal; computing a prediction of a degradation of the uplink signal using the quality of the received signal, and transmitting the uplink signal according to the predicted degradation of the uplink signal.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: January 26, 2010
    Assignee: The DIRECTV Group, Inc.
    Inventor: Harish N. Patel
  • Patent number: 7653148
    Abstract: A method and apparatus for modulating an input signal comprised of an ordered series of samples separated by a substantially constant period T comprising the steps of providing a carrier signal, the carrier signal comprised of a series of samples separated by a substantially constant period T, wherein one of the carrier samples corresponds to each of the input signal samples, selecting a plurality of N successive samples from the series of input signal samples, the series of samples having an input order, for each of the N selected samples in parallel, multiplying the selected sample by the corresponding carrier sample and recombining the N multiplied samples while maintaining the input order.
    Type: Grant
    Filed: January 28, 2009
    Date of Patent: January 26, 2010
    Assignee: Liquid Xstream Systems Inc.
    Inventors: Jean-Francis Kisovec, Benoit Dufresne
  • Publication number: 20100014611
    Abstract: Disclosed is a binary signal modulator for minimizing deterioration of receiving performance caused by phase error. The binary signal modulator receives binary signals, and converts the binary signals into complex symbols according to a predetermined mapping relation. Here, the mapping relation is generated when a plurality of mapping symbols are arranged on a plurality of trajectories so that the distance between the mapping symbols is greater than or equal to a predetermined distance and the phase between the mapping symbols is greater than or equal to a predetermined angle from among the trajectories starting from a plurality of points on the complex plane, and a distance between the trajectories is greater than or equal to the minimum distance from among the distances between the points.
    Type: Application
    Filed: December 14, 2007
    Publication date: January 21, 2010
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Byung-Jae Kwak, Nah-Oak Song, Dong-Seung Kwon
  • Publication number: 20100014610
    Abstract: A Ka-band transmitter. The transmitter is in a self-contained module that contains a radio frequency (RF) channel. A phase lock oscillator drives an RF signal path in the RF channel at a fundamental frequency. In-phase data (I-data) and Quadrature data (Q-data) difference signals are converted to single ended signals and filtered in a pair of low pass filters and passed as inputs to a Quadriphase Shift Keying (QPSK) vector modulator in the RF signal path, e.g., an in-line even-harmonic modulator. The output of the QPSK vector modulator, is a Ka-band signal that is passed to a driver which may drive a load, e.g., an antenna.
    Type: Application
    Filed: July 15, 2008
    Publication date: January 21, 2010
    Applicant: USA as represented by the Administrator of the National Aeronautics and space
    Inventor: Jeffrey M. Jaso
  • Patent number: 7649956
    Abstract: A modulation and demodulation system capable of minimizing a bit error rate in a six-phase phase modulation method. A senary signal phase-modulated and outputted by a modulator is received and phase-modulated by a destination demodulator to a binary signal before conversion by the modulator. The modulator assigns (0, 0), (0, 1), (0, 2), (1, 2), (1, 1) and (1, 0) which are senary signals (bi, ti) to first to sixth phases respectively. The demodulator performs a conversion process from the senary signals to the binary signals, for instance, by storing transmitted senary signals and sequentially converting every senary signal of length m to binary signal of length b so as to output them. The process of the demodulator assigns the first to sixth phases as the senary signals (bi, ti) to (0, 0), (0, 1), (0, 2), (1, 2), (1, 1) and (1, 0) respectively.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: January 19, 2010
    Assignee: NEC Corporation
    Inventors: Seiichi Noda, Shinichi Koike
  • Patent number: 7649959
    Abstract: A method is provided for specifying a transmission mode for each signal portion of a multi-carrier signal transmitted between a first and second device. The method includes defining an adaptive modulation and coding set divided into a plurality of subsets, each of the plurality of subsets including a plurality of transmission modes for transmitting a signal portion. The method further includes selecting a transmission mode subset from the plurality of subsets for transmission of the multi-carrier signal from a first to a second device, selecting a signal portion transmission mode for each signal portion from the plurality of transmission modes of the selected transmission mode subset, defining semantic bits that indicate the selected transmission mode subset, defining an indicator bit for each signal portion indicating the selected sub-carrier transmission mode, and transmitting the semantic bits and the indicator bit for each signal portion from a first to a second device.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: January 19, 2010
    Assignee: Nokia Corporation
    Inventors: Olav Tirkkonen, Paolo Priotti, Ulrico Celentano
  • Publication number: 20090323782
    Abstract: Provided is a non-federated multi-function exciter. The non-federated multi-function exciter includes a waveform generator subsystem operable to provide waveforms programmable in time, duration, slope and frequency. A transmission subsystem is coupled to the waveform generator, the transmission subsystem having a first upconverter and a second upconverter coupled to the first upconverter. A communication modulation subsystem is coupled to the second upconverter of the transmission subsystem. A reference clock subsystem coupled to the waveform generator subsystem, the transmit subsystem and the communication modulation subsystem. The non-federated multi-function exciter is operable to generate interleaved radar and communication signals.
    Type: Application
    Filed: April 21, 2008
    Publication date: December 31, 2009
    Inventors: David W. Baker, Joel C. Blumke, Ralston S. Robertson, Chester Lo
  • Publication number: 20090323863
    Abstract: A phase-shift based pre-coding scheme used in a transmitting side and a receiving side that has less complexity than those of a space-time coding scheme, that can support various spatial multiplexing rates while maintaining the advantages of the phase-shift diversity scheme, that has less channel sensitivity than that of the pre-coding scheme, and that only requires a low capacity codebook is provided.
    Type: Application
    Filed: September 4, 2009
    Publication date: December 31, 2009
    Inventors: Moon-Il Lee, Bin-Chul Ihm, Jin-Young Chun, Jae-Won Chang, Jin-Hyuk Jung
  • Publication number: 20090323862
    Abstract: A mobile telecommunication device includes a digital baseband processing unit and an analog baseband processing circuit. The digital baseband processing unit is configured to extract a difference value of current ramping data of ramping data of ramping samples of a ramping profile from previous ramping data, the current ramping data and the previous ramping data having a first bit number, and to transmit the difference value to the analog baseband processing unit as sample difference ramping data having a second bit number which is smaller than a first bit number. The analog baseband processing unit configured to receive the sample difference ramping data, and to generate a ramping up/down signal of the first bit number based on the sample difference ramping data, wherein the ramping up/down signal controls an output power level of the mobile telecommunication device.
    Type: Application
    Filed: June 29, 2009
    Publication date: December 31, 2009
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Jung-Hun Heo
  • Patent number: 7639766
    Abstract: A circuit including an analog to digital converter and a processor is disclosed. The analog to digital converter may be configured to generate a plurality of samples from a received signal in response to a reference signal. The processor may be configured to designate one of an early sample of the samples and a late sample of the samples as an ideal sample in response to a first timing error of an on-time sample of the samples being greater than one-half a sample period of the received signal.
    Type: Grant
    Filed: September 27, 2004
    Date of Patent: December 29, 2009
    Assignee: VIA Telecom Co., Ltd.
    Inventor: Paul Chun-Hsiung Wei
  • Publication number: 20090316828
    Abstract: An apparatus, and an associated methodology, for facilitating communication of data in a wireless communication systems. Binary data are modulated to form modulated symbols on parallel paths. The symbols formed on one of the parallel paths are phase-offset by a phase rotator to form phase-offset symbols. The parallel paths of symbols provide the symbols, both the phase-offset symbols and the symbols that are not phase-offset, to an Alamouti encoder. As a result, the dynamic range of the transmitted RF signals is reduced due to the introduction of the phase offset between the symbols of the parallel paths applied to the Alamouti encoder.
    Type: Application
    Filed: June 23, 2008
    Publication date: December 24, 2009
    Applicant: RESEARCH IN MOTION LIMITED
    Inventor: Shouxing Qu
  • Publication number: 20090310708
    Abstract: A transmitter, channel coder, and method for coding and transmitting a sequence of symbols in a digital communication system utilizing soft pilot symbols. In one embodiment, the transmitter transmits a set of soft pilot symbols with higher reliability than the remaining symbols in the sequence by modulating the soft pilot symbols with a lower order modulation such as BPSK or QPSK while modulating the remaining symbols with a higher order modulation such as 16 QAM or 64 QAM. The transmitter shares the modulation type and location (time/frequency/code) of the soft pilot symbols with a receiver. Unlike traditional fixed pilots, the soft pilots still carry some data. Additionally, the soft pilots are particularly helpful in establishing the amplitude reference essential in demodulating the higher order modulation symbols. In another embodiment, soft pilot symbols are inserted by low-level puncturing of channel encoded bits and replacing the punctured bits with known bit patterns.
    Type: Application
    Filed: September 29, 2008
    Publication date: December 17, 2009
    Inventors: Jung-Fu Cheng, Tracy Fulghum, Douglas Cairns
  • Publication number: 20090310707
    Abstract: A transmitter, channel coder, and method for coding and transmitting a sequence of symbols in a digital communication system utilizing soft pilot symbols. In one embodiment, the transmitter transmits a set of soft pilot symbols with higher reliability than the remaining symbols in the sequence by modulating the soft pilot symbols with a lower order modulation such as BPSK or QPSK while modulating the remaining symbols with a higher order modulation such as 16 QAM or 64 QAM. The transmitter shares the modulation type and location (time/frequency/code) of the soft pilot symbols with a receiver. Unlike traditional fixed pilots, the soft pilots still carry some data. Additionally, the soft pilots are particularly helpful in establishing the amplitude reference essential in demodulating the higher order modulation symbols. In another embodiment, soft pilot symbols are inserted by low-level puncturing of channel encoded bits and replacing the punctured bits with known bit patterns.
    Type: Application
    Filed: September 29, 2008
    Publication date: December 17, 2009
    Inventors: Jung-Fu Cheng, Tracy Fulghum, Douglas Cairns
  • Patent number: 7630455
    Abstract: In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: December 8, 2009
    Assignee: Panasonic Corporation
    Inventors: Yutaka Murakami, Shinichiro Takabayashi, Masayuki Orihashi, Akihiko Matsuoka
  • Patent number: 7630456
    Abstract: An apparatus comprising a first circuit and a second circuit. The first circuit may be configured to generate an MPEG packet data stream. The second circuit may be configured to (i) scramble the data stream to generate a scrambled data stream, (ii) encode the scrambled data stream to generate an encoded data stream, (iii) interleave the encoded data stream, (iv) encode the interleaved data stream, (v) modulate the encoded data stream, and (vi) filter the modulated data stream.
    Type: Grant
    Filed: September 9, 2002
    Date of Patent: December 8, 2009
    Assignee: LSI Corporation
    Inventors: Advait M. Mogre, Atousa Haj-Shir-Mohammadi, Toshiyaki Yoshino
  • Patent number: 7630453
    Abstract: Disclosed is a method and a system for performing N-ary modulation in which bit errors may be reduced against symbol error. A binary signal, a bit length thereof being n, is associated with N-ary signals arranged in first and second phase planes respectively for transmission, wherein N is not a number belonging to powers of 2 but is a number belonging to a series beginning from 12 and sequentially doubled, that is, any one of 12, 24, 48, 96, . . . , and wherein n is such that, if the bit length n is 7, 9, 11, 13, . . . , the number N is 12, 24, 48, 96, . . . , respectively, two out of the n bits are allocated for identifying four quadrants of the first phase plane, two out of the remaining (n?2) bits are allocated for identifying four quadrants of the second phase plane. The binary signal of three out of the n bits is converted into two digits of ternary signals (T1, T2). The ternary signals are mapped to the first and second phase planes with rotational symmetry of 90° or with axial symmetry.
    Type: Grant
    Filed: March 8, 2005
    Date of Patent: December 8, 2009
    Assignee: NEC Corporation
    Inventor: Seiichi Noda
  • Publication number: 20090296853
    Abstract: A transmitter architecture and method of modulation that include a rotation-direction control circuit for varying the direction of rotation of phase transitions of a phase modulation based on the occurrence of a predetermined pattern of input data. This variation of rotation direction by the rotation-direction control circuit maintains the output spectrum of a modulated signal within the spectral mask requirements of an associated communications standard and thereby enables the use of non-linear power amplifiers in applications that generally require linear amplifiers.
    Type: Application
    Filed: May 30, 2008
    Publication date: December 3, 2009
    Applicant: ZEROG WIRELESS, INC.
    Inventors: Meng-Chang Doong, Jia-Yi Chen, Thomas Lee
  • Patent number: 7627058
    Abstract: A method of performing alternating quadratures differential binary phase shift keying modulation involves limiting phase changes between adjacent in time modulator output symbols to ±90 °, and transmitting modulator input data by 0° and 180° phase differences between non-adjacent in time modulator output symbols.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: December 1, 2009
    Assignee: Teledyne Licensing LLC
    Inventor: Yefim Samuilovich Poberezhskiy
  • Publication number: 20090290631
    Abstract: Methods and apparatus for reducing the bandwidth of modulation signals in a phase path of a polar modulation transmitter. An exemplary method includes generating a phase difference modulation signal for a phase path of a polar modulation transmitter, and filtering the phase difference modulation signal using a linear-phase filter. Filtering the phase difference modulation signal may be performed by first detecting samples in the phase difference modulation signal that have phase difference values in excess of a phase difference threshold and then filtering samples in the vicinity of the threshold-violating samples to remove the threshold-violating events. Alternatively, all samples may be filtered, i.e., without regard as to whether any given sample exceeds a phase difference threshold, to remove large phase difference changes in the phase difference modulation signal, or a combination of linear-phase and nonlinear filters may be used to remove the large phase difference changes.
    Type: Application
    Filed: May 20, 2008
    Publication date: November 26, 2009
    Inventors: Wayne S. Lee, Tony L. Wong
  • Patent number: 7623000
    Abstract: The invention is directed at a hybrid modulation apparatus which combines a polar modulation circuit and a linear modulation circuit. The hybrid apparatus allows a communications device to function as a polar or a linear modulation circuit with less components as the output of the linear modulation circuit is an input of the polar modulation circuit.
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: November 24, 2009
    Assignee: Icera Canada ULC
    Inventors: Tajinder Manku, Abdellatif Bellaouar
  • Publication number: 20090285319
    Abstract: A method for generating a preamble of a data unit for transmission via a communication channel includes generating a first field of the preamble using one of a first sequence or a second sequence, such that the first sequence and the second sequence are complementary sequences such that a sum of out-of-phase aperiodic autocorrelation coefficients of the first sequence and the second sequence is zero; generating, using the other one of the first sequence or the second sequence, an indicator of a start of a second field of the preamble, the second field associated with channel estimation information, such that the indicator of the start of the second field immediately follows the first field; and generating the second field of the preamble.
    Type: Application
    Filed: May 15, 2009
    Publication date: November 19, 2009
    Inventors: Hongyuan Zhang, Rohit U. Nabar, Songping Wu, Hui-Ling Lou, Quan Zhou
  • Publication number: 20090280758
    Abstract: A wireless communication unit comprises a transmitter having an analogue feedback power control loop having a power control function arranged to set an output power level of the transmitter. The power control function comprises a predictor sub-system arranged to reduce sensitivity to loop latency of the analogue feedback power control loop. The use of a predictor sub-system provides reduced sensitivity to loop latency, gain variations and delay.
    Type: Application
    Filed: December 23, 2004
    Publication date: November 12, 2009
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Patrick J. Pratt, Michael A. Milyard, Daniel B. Schwartz, Philip C. Warder
  • Patent number: 7606321
    Abstract: The system and method enable simpler analog processing in a transmitter by reducing the number of bits in a digital signal through delta sigma modulation. Selection of current sources in a digital to analog converter of the transmitter is done using a randomization circuit.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: October 20, 2009
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Publication number: 20090257476
    Abstract: A transmission device of the present, invention includes a baseband waveform generator to generate a transmission signal by using a transfer function H0(f) that is in a relation of a matched filter with a transfer function H1(f) in an analog domain of a transmission side and a reception side connected through a wireless channel, and transmits the transmission signal generated fay the baseband waveform generator.
    Type: Application
    Filed: April 8, 2009
    Publication date: October 15, 2009
    Inventor: Katsumi WATANABE
  • Patent number: 7599446
    Abstract: A modulation device comprises a modulation unit (2) that modulates data in a hierarchical manner using multiple types of modulation techniques, and a transmission unit (3) that transmits the hierarchically modulated data. A demodulation device comprises a receiving unit (4) that receives the hierarchical modulation data having been subjected to hierarchical modulation using multiple types of modulation techniques, and a demodulation unit (6) that demodulates the hierarchical modulation data using a demodulation technique corresponding to a specific hierarchy of the hierarchical modulation data.
    Type: Grant
    Filed: September 15, 2003
    Date of Patent: October 6, 2009
    Assignee: NTT DoCoMo, Inc.
    Inventors: Sung Uk Moon, Takahiro Hayashi, Toshiyuki Futakata
  • Publication number: 20090245421
    Abstract: Aspects describe maximizing a Euclidean distance for an ACK transmission as a function of the number of bits in a HARQ-ACK and a modulation order. Encoding includes placing escape sequences in the HARQ-ACK, wherein the number of escape sequences is based on the number of bits and the modulation order. Multiple encoded ACK blocks are combined to obtain a vector sequence that is multiplexed with the encoded data and interleaved, such as on a “time-first” manner. Scrambling is performed as a function of the size and the modulation order. For a 1-bit ACK, the scrambling is performed to achieve any two corners in any constellation for transmission for the ACK. For a 2-bit ACK, the scrambling is performed to achieve any four corners in any constellation for transmission for the ACK.
    Type: Application
    Filed: March 25, 2009
    Publication date: October 1, 2009
    Applicant: QUALCOMM INCORPORATED
    Inventors: Juan Montojo, Peter Gaal
  • Patent number: 7595702
    Abstract: A modulation apparatus 24 comprises a monitoring section 207 operable to monitor information about a control voltage applied to a VCO 201 as control voltage information, during any period, when a low-frequency signal having a frequency within a loop band of a PLL circuit is input at least before an LPF 209, a correction table storing section 206 operable to associate the control voltage information monitored by the monitoring section 207 as information about a control voltage after correction with information about a control voltage before correction, and store the associated information as a correction table, and a correction section 204 operable to correct a control voltage applied to the VCO 201 based on the correction table stored in the correction table storing section.
    Type: Grant
    Filed: July 5, 2007
    Date of Patent: September 29, 2009
    Assignee: Panasonic Corporation
    Inventor: Masakatsu Maeda
  • Patent number: 7596187
    Abstract: A mixer circuit accumulates I signal (digital signal of first channel) having its band limited by low-pass filter and first carrier signal to perform two-phase shift keying modulation thereon. An adder adds fundamental-wave component of bit clock signal BCK into Q signal (digital signal of second channel) having its band limited by the another low-pass filter to obtain a resultant added-up signal. Another mixer circuit accumulates the added-up signal and second carrier signal to perform two-phase shift keying modulation thereon. Output signals of the mixer circuits are input to another adder so that they may be added up to obtain a QPSK signal as a modulated quadrature signal. The QPSK signal contains frequency signals whose frequencies are a sum of bit clock frequency and carrier frequency and a difference between them. When demodulating, the carrier signal and the bit clock signal are reproduced using the frequency signals.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: September 29, 2009
    Assignee: Sony Corporation
    Inventors: Kazuji Sasaki, Masaya Takano
  • Patent number: 7586293
    Abstract: Provided is a digital modulation circuit constructed with only a digital circuit. The digital modulation circuit includes: a clock generator which generates a reference clock pulse having a predetermined period; an up/down counter which generates a count value having predetermined bits by up-counting or down-counting the reference clock pulse and outputs a bit in the count value as a transmission signal; a controller which determines a counting start/end time point of the up/down counter and determine which one of the up-counting operation and the down-counting operation of the up/down counter is to be performed, according to a value of digital transmission data that is to be transmitted; and a band-pass filter which converts a waveform of the transmission signal output from the up/down counter into a sine waveform.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: September 8, 2009
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Man Suk Seo, Hyung Cheol Park, Seong Soo Lee, Sang Yub Lee, Chang Soo Yang, Wan Cheol Yang
  • Publication number: 20090220027
    Abstract: Data symbols, transmitted by OFDM radio using at least two transmission antennae, are coded by a DSTBC coding and a DSTFBC coding. Two adjacent data symbols of a selected sub-carrier are provided for initializing a DSTFBC coding in a sub-carrier direction and are used for DSTFBC coding of similarly positioned data symbols in further sub-carriers in the sub-carrier. The DSTFBC coding is carried out from the data symbols of the first sub-carrier direction. In each sub-carrier the two data symbols formed by DSTFBC coding are used for initializing a DSTBC coding in the OFDM symbol direction. In the reverse direction, two sequential DSTBC coded data symbols on a first sub-carrier for initializing a DSTFBC coding in a sub-carrier direction and are used for DSTFBC coding of similarly positioned data symbols in further sub-carriers for DSTFBC coding from the data symbols of the first sub-carrier over the adjacent sub-carriers.
    Type: Application
    Filed: December 15, 2006
    Publication date: September 3, 2009
    Inventors: Rüdiger Halfmann, Cornelius Heckrott, Martin Weckerle
  • Patent number: 7583894
    Abstract: Methods and apparatus are described for modulating an optical signal using electroabsorption in conjunction with an optical interferometer. Phase-shift keying modulation can be achieved with lower amplitude modulator drive signals than conventional methods by splitting the signal to be modulated into multiple optical modes and interferometrically combining the modes after modulating at least one of the modes with an EAM. Using the present invention, the extinction ratio performance of ASK can be significantly improved for a given drive voltage or a desired extinction ratio can be achieved with a substantially lower drive voltage. Hence, the elecro-optic bandwidth of EAMs can be enhanced by overcoming the trade-off relationship between extinction ratio and bandwidth. Furthermore, the present invention can be used to generate other modulation formats, such as QPSK or QAM, with much lower drive voltages, thereby reducing the cost and power consumption of the high-speed drive electronics for the modulation.
    Type: Grant
    Filed: September 21, 2006
    Date of Patent: September 1, 2009
    Assignee: Alcatel-Lucent USA Inc.
    Inventor: Inuk Kang
  • Patent number: 7570702
    Abstract: An apparatus and a system, as well as a method and an article, may include shifting a digital baseband signal upward along a frequency spectrum by an amount greater than its bandwidth to provide an elevated frequency digital baseband signal, which in turn may be selected as a single-sideband signal after an image reject mixer is used to further shift the elevated frequency digital baseband signal, and modest filtering techniques are used to reject unwanted sidebands and any carrier that is present.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: August 4, 2009
    Assignee: Intel Corporation
    Inventors: Alan E. Waltho, Jeffrey Schiffer
  • Patent number: 7564923
    Abstract: A transmitter digital signal processor (DSP) circuit has a transmit frequency represented by n-bit data output from a look up table (LUT). The n-bit data is outputted to an n-bit accumulator structured to overflow at a rate based on the output n-bit data to output a phase. The circuit further has device structured to add an n-bit signed constant to the accumulator to offset the frequency represented by the n-bit data output from the LUT. A transceiver on a semiconductor chip may include as part of a transmitter circuit, a transmit DSP circuit that has the LUT, accumulator and device providing an n-bit signed constant to the accumulator to offset a transmit frequency in order to allow a receiver circuit on the transceiver to communicate directly with the transmitter circuit, and thus allowing testing of the transceiver.
    Type: Grant
    Filed: October 27, 2005
    Date of Patent: July 21, 2009
    Assignee: Cypress Semiconductor Corporation
    Inventors: Mark R. Gehring, Russell R. Moen, Brent R. Jensen
  • Patent number: 7555061
    Abstract: An optical sender is disclosed that operates in a Differential Quadrature Phase Shift Keying modulation scheme for high speed optical transmission and is capable of performing logical calculations at a low speed. The optical sender transmits a Differential Quadrature Phase Shift Keying (DQPSK) signal generated with modulation signals ?k and ?k so that a signal directly output from a signal receiver corresponding to the optical sender is in agreement with data signals Ik and Qk to be transmitted. The signal receiver is capable of modulation by DQPSK, and the modulation signals ?k and ?k are precoded by using the data signals Ik and Qk and the modulation signals one symbol earlier (?k?1 and ?k?1) . The optical sender includes plural precoders that perform logical calculation simultaneously and in parallel on plural data signals one period after another period.
    Type: Grant
    Filed: June 20, 2005
    Date of Patent: June 30, 2009
    Assignee: Fujitsu Limited
    Inventors: Toru Katagiri, Takeshi Hoshida, Tomoo Takahara, Kentaro Nakamura, Naoki Kuwata
  • Patent number: 7551903
    Abstract: A modulator circuit comprises a negative impedance amplifier which is operable such that a signal applied to the amplifier is reflected and amplified. Switching means are provided for switching the impedance of the amplifier between two reflecting states such that the reflected and amplified signal is phase modulated. The impedances of the negative impedance amplifier are selected such that the phase of the reflected and amplified signal in the first reflecting state differs substantially from the phase of the reflected and amplified signal in a second reflecting state. For example, the phase switches by substantially 180 degrees. Preferably the impedances of the negative impedance amplifier in the two reflecting states are selected such that the reflection gain of the amplifier in the two reflecting states is substantially the same such that the reflected and amplified signal is a binary phase shift keyed.
    Type: Grant
    Filed: May 15, 2006
    Date of Patent: June 23, 2009
    Inventors: Adrian N Farr, Ian J Forster
  • Patent number: 7551904
    Abstract: An method and apparatus for power amplification in a mobile communication system, wherein a signal converter for receives signals from a baseband-side, modulates the received signals into oversampled baseband digital signals, and generates signals having a constant envelope with the oversampled base band digital signals, an up-converter up-converts the generated signals having the constant envelope to Radio Frequency (RF) signals for output, and a power amplifier amplifies the RF signals according to system setup levels and outputs envelope signals of a predetermined level.
    Type: Grant
    Filed: October 31, 2005
    Date of Patent: June 23, 2009
    Assignees: Samsung Electronics Co., Ltd, Postech Foundation
    Inventors: Dong-Geun Lee, Bum-Man Kim, Jeong-Hyeon Cha
  • Publication number: 20090154598
    Abstract: A digital modulator in a radio transmitter includes circuitry for switching between Gaussian Minimum Shift Keying (GMSK) and Phase-Shift Keying (PSK) while maintaining spectral mask requirements. The digital modulator of the present invention includes both GMSK and PSK symbol mappers that produce PSK in-phase and quadrature symbols and GMSK symbols, respectively, to a pulse shaping block. Based on opposite phases of a modulation control signal, the symbol mappers produce either modulated data or a steam of logic zeros to the pulse shaping block. The pulse shaping block filters the received data and multiplexes the data so that each modulated data stream receives non-zero data during a guard time to avoid abrupt changes in the modulated signal that would violate the spectral mask requirements.
    Type: Application
    Filed: February 24, 2009
    Publication date: June 18, 2009
    Applicant: BROADCOM CORPORATION
    Inventor: HENRIK T. JENSEN
  • Publication number: 20090154597
    Abstract: A transmitter includes a dual mode modulator and an amplifier coupled to the dual mode modulator. The dual mode modulator implements a linear modulation scheme during a first mode of the modulator to produce a variable envelope modulated signal. The dual mode modulator implements a non-linear modulation scheme during a second mode of the modulator to produce a constant envelope modulated signal. The amplifier is biased as a linear amplifier during the first mode of the modulator and is biased as a non-linear amplifier during the second mode of the modulator. A feed-forward connection between the dual mode modulator and the amplifier is used to indicate a change in modulation mode and to adjust the bias of the amplifier. A power of the constant envelope modulated signal is increased such that an operating point of the amplifier remains substantially constant during the first and second modes of the modulator.
    Type: Application
    Filed: January 5, 2009
    Publication date: June 18, 2009
    Applicant: Broadcom Corporation
    Inventor: Meng-An PAN
  • Patent number: 7545884
    Abstract: A digital baseband modulation apparatus includes: a spread modulation part for complex spreading an I component signal and a Q component signal of a send signal so as to output an output signal; and an amplitude conversion part for decreasing the amplitude component of the output signal to the half when the output signal is output on the I axis or on the Q axis.
    Type: Grant
    Filed: January 14, 2004
    Date of Patent: June 9, 2009
    Assignee: Fujitsu Limited
    Inventor: Kensuke Sawada
  • Patent number: 7542511
    Abstract: Systems and methods for wireless transmission of uncompressed HDTV signals are disclosed. In one embodiment, a method for transmitting an uncompressed HDTV signal over a wireless RF link, comprises providing a stream of regenerated data from the uncompressed HDTV signal; providing a first clock signal synchronized to said stream of regenerated data; encoding said stream of regenerated data, producing a stream of encoded data; providing a second clock signal synchronized to said stream of encoded data; demultiplexing said stream of encoded data, using said second clock signal, into an I data stream and a Q data stream; modulating a carrier with said I data stream and said Q data stream; and transmitting said carrier in a signal over the wireless RF link.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: June 2, 2009
    Assignee: The Boeing Company
    Inventors: Kurt W. Loheit, William A. Salter
  • Patent number: 7543213
    Abstract: To provide a turbo decoding method capable of significantly improving efficiency of a determination as to whether or not to end decoding. If the decoding by a turbo decoder is started, a soft decision value of an element decoder is derived, and an ECR of a current frame is estimated from the soft decision value by an ECR criterion deriving portion. If determined to be an end as a result of an end determination of the decoding by the turbo decoder from a result of comparison with a last ECR value and the maximum number of times of repetition of decoding, a hard decision result and a decoding result are outputted, and if not determined to be the end, the number of times of repetition is counted up so as to repeat the above process.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: June 2, 2009
    Assignee: NEC Corporation
    Inventor: Hua Lin
  • Patent number: 7541864
    Abstract: The invention relates to a power amplifier having a phase amplification path with a phase amplification stage within said phase amplification path. Here the phase amplification stage receives a magnitude component of the power amplified output signal, and the phase amplification stage is responsive to a phase component of the input signal, a magnitude component of the input signal, and the received magnitude component of the power amplified output signal for generating the power amplified output signal. The invention also relates to a power amplifier having a magnitude amplification path for a magnitude component of the input signal with a magnitude amplifier stage within said magnitude amplification path, and with the power amplifier further having a phase amplification path with a phase amplification stage within said phase amplification path.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: June 2, 2009
    Assignee: Silicon Power Devices APS
    Inventor: Carsten Rasmussen
  • Patent number: 7539266
    Abstract: A network device comprises a PSK modulator that PSK modulates a header portion of a data packet at a first effective throughput and that PSK modulates outbound data at a second effective throughput to form a PSK modulated payload. A symbol modulator symbol modulates the outbound data at a third effective throughput to form a symbol modulated payload. A modulation selection unit forms a payload portion of the data packet based on at least one of the PSK modulated payload and the symbol modulated payload.
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: May 26, 2009
    Assignee: Marvell International Ltd.
    Inventor: Yungping Hsu