Transmitter Patents (Class 375/146)
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Patent number: 7801235Abstract: A wireless communication device that includes more than two antennas considers only two of those antennas for use in receiving any particular wireless packet. During reception of an initial portion of a wireless packet, a quality metric may be measured for each of the two antennas being considered. One of the two antennas may then be selected to receive a payload portion of the wireless packet based on the measured metrics. In at least one embodiment, a different pair of antennas is considered for each successive received packet.Type: GrantFiled: August 30, 2004Date of Patent: September 21, 2010Assignee: Intel CorporationInventors: Ashim Biswas, Xintian E. Lin
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Patent number: 7796675Abstract: A device for site monitoring is disclosed. The device may include a communication interface configured to receive site monitoring data from a site monitoring system. The communication interface may also be configured to wirelessly transmit the site monitoring data to a base station. The site monitoring data may include a device identification. The device also may include a processor and memory. The memory also may include two pseudonoise (PN) codes, namely a first PN code and a second PN code. The site monitoring data may be received from the site monitoring system. The site monitoring data may be spread using the first PN code to provide first spread site monitoring data. The first spread site monitoring data may be spread using the second PN code to provide second spread site monitoring data. The second spread site monitoring data may be transmitted using a burst direct sequence spread spectrum radio signal.Type: GrantFiled: March 12, 2008Date of Patent: September 14, 2010Assignee: Recon Dynamics, LLCInventors: David Carter, Sy Prestwich, James R. Baker, Scott Bevan
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Patent number: 7796676Abstract: A signalling system is provided which can be used to update the prices of goods which are electronically displayed on supermarket shelves. The signaling system may include a first signalling device having an input terminal for receiving electrical message data received from a central computer system, a spread spectrum encoder for encoding the received message data and an electroacoustic converter for converting the encoded data into corresponding acoustic signals and for transmitting the acoustic signals from the transmission medium and for converting the received acoustic signals into corresponding electrical signals, a spread spectrum decoder for decoding the received signals and a message regenerator for regenerating the message data transmitted by the first signalling device from the signals output by the decoder.Type: GrantFiled: October 21, 2004Date of Patent: September 14, 2010Assignee: Intrasonics LimitedInventor: Michael John Barclay
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Patent number: 7792179Abstract: An efficient scheme for CDMA coding constructs codes by generating longer code sequences (430) via concatenation, from an existing set of short sequences (410, 420). The sequences may be spreading, scrambling and or training or channel estimation (such as midamble) sequences. The invention allows extension of sequences without performing an exhaustive search for sequences with optimal desired properties, as well as extension of the sequence duration to improve the detection of wanted signals via the use of a conventional matched filter, a multi-user detector or an adaptive filter/equaliser.Type: GrantFiled: November 3, 2003Date of Patent: September 7, 2010Assignee: IPWireless, Inc.Inventors: Peter Bruce Darwood, Alan Edward Jones
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Publication number: 20100220768Abstract: The embodiments of the present invention disclose an apparatus for transmitting multi-ary error-correcting codes, an apparatus for receiving multi-ary error-correcting codes, a data transmission system, and relevant methods to simplify operations. The apparatus for transmitting multi-ary error-correcting codes includes: a multi-ary channel encoder, adapted to perform multi-ary coding for source data frames of a user to obtain encoded sequences; a symbol mapper, adapted to perform symbol mapping for the encoded sequences to obtain symbol sequences; and a spreading and interleaving unit, adapted to spread and interleave the symbol sequences. Moreover, a corresponding apparatus for receiving multi-ary error-correcting codes, a data transmission system, and relevant methods are provided.Type: ApplicationFiled: April 30, 2010Publication date: September 2, 2010Inventors: Yanxing Zeng, Raymond W.K. Leung, Ying Jin, Chao Zhang
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Patent number: 7787519Abstract: With the object of efficiently transmitting a variety of different information signals by utilizing the multi-carrier characteristics of Multi-carrier/DS-CDMA, the present invention is characterized in that, when, in an uplink transmission from a plurality of mobile stations to a base station, the mobile stations transmit a preamble to the base station before transmitting an information symbol sequence, the mobile stations individually select a carrier from among a plurality of carriers, and, up until receiving a preamble receipt confirmation signal from the base station with a prescribed maximum number of preamble transmissions serving as an upper limit number; the mobile stations repeatedly transmit a preamble by means of the selected carrier and vary the transmission power used for the transmissions of each carrier.Type: GrantFiled: November 8, 2002Date of Patent: August 31, 2010Assignee: NTT DoCoMo, Inc.Inventors: Shingo Suwa, Hiroyuki Atarashi, Mamoru Sawahashi
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Patent number: 7787517Abstract: Accordingly, a method and apparatus are provided to convert received content into a first stream and a second stream, to transmit said first stream using a first tone and to transmit said second stream using an orthogonal scheme. A layering scheme is used to transmit the base stream covering a smaller area and an enhanced stream is used to cover a large utilizing orthogonal scheme.Type: GrantFiled: January 28, 2005Date of Patent: August 31, 2010Assignee: QUALCOMM IncorporatedInventors: Ashok Mantravadi, Anand D. Subramaniam, Krishnamurthy Viswanathan, legal representative, Dhananjay Ashok Gore
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Publication number: 20100215079Abstract: OFDM symbols are generated using data from one or more users or from one or more data sources represented on a number of sub-carriers. To inhibit multiple-access interference on application of the CDMA principle, the data are transformed in a data-source specific manner and only subsequently allocated to the sub-carriers, independently of the transformation.Type: ApplicationFiled: May 3, 2010Publication date: August 26, 2010Inventors: Elena Costa, Dirk Galda, Harald Haas, Hermann Rohling, Egon Schulz
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Publication number: 20100215080Abstract: A transmission apparatus according to the present invention includes: an encoding section; a modulation section; a variable-SF spreading section that performs spreading with variable SF according to control information A from a control section; an IDFT section that performs IDFT on output from the spreading section; a GI inserting section; a parallel/serial conversion section that converts output from the GI inserting section into a serial data sequence; a digital/analog conversion section; and an RF section that transmits a signal from an antenna after converting the signal to a frequency band for analog signal transmission and controlling it to an appropriate transmission power. The control section is configured to generate control information A for determining the variable SF and input the information A to the variable-SF spreading section and the RF section. In control information A, SF is varied depending on transmission power required.Type: ApplicationFiled: September 12, 2008Publication date: August 26, 2010Applicant: SHARP KABUSHIKI KAISHAInventors: Yasuhiro Hamaguchi, Minoru Kubota, Hideo Namba, Shimpei Toh, Kazunari Yokomakura
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Patent number: 7782925Abstract: An ultra wideband direct sequence code division multiple access (UWB DS-CDMA) (101) transmitter is provided. It includes a first multiplier (125) receiving two input signals, where the input signals are selected from a multi-level code signal (117), a transmit data signal (123), and a radio frequency (RF) center frequency signal (121), and responsive to the two input signals, generating a combined signal (127). Further included is a network (119) receiving a code-clock signal (113) aligned with the multi-level signal (117), multiplying the frequency of the code-clock signal (113) by a factor, and responsive thereto, producing the RF center frequency signal (121). Also provided is a second multiplier (129) receiving the combined signal (127) and the other of the input signals (117, 123, 121), and responsive thereto, generating an output signal (131).Type: GrantFiled: August 31, 2005Date of Patent: August 24, 2010Assignee: Freescale Semiconductor, Inc.Inventors: John W. McCorkle, Phuong T. Huynh
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Patent number: 7782923Abstract: A wireless communication system, to control a peak power to an average power ratio because an amplifier characteristic of the wireless communication system include non-linear characteristic if input signal large the amplifier makes distortions. A wireless communication system comprises for suppressing a peak power to an average power ratio to process known signal like a pilot signal.Type: GrantFiled: January 13, 2006Date of Patent: August 24, 2010Assignee: Fujitsu LimitedInventors: Daisuke Ogawa, Takashi Dateki, Hideto Furukawa, Nobukazu Fudaba
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Publication number: 20100208771Abstract: A system and method for spreading and de-spreading a signal at an antenna. A Direct Spatial Antenna Modulation (DSAM) system makes use of the spatial characteristics of a radiating antenna structure to directly alter a signal transmitted or received by the radiating structure. When used for transmitting data, a data stream maps a carrier to different spatial points of excitation in the antenna structure, where each chosen configuration has different radiating characteristics including phase, amplitude, and polarization, which can be used represent data symbols. A code spreading sequence is applied to switch the output of the DSAM antenna to spatial points in the antenna to spread an input signal. The code spreading sequence is applied to a receive antenna to de-spread a previously spread signal. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this Abstract.Type: ApplicationFiled: March 17, 2010Publication date: August 19, 2010Inventors: Brecken H. Uhl, Arthur D. Hurtado, Daniel A. Law
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Publication number: 20100208772Abstract: A wireless communications system employs code-division multiple access information transmission techniques where the uplink and downlink transmission bandwidths are unequal. The higher bandwidth is an integer multiple of the lower bandwidth. The present system requires a base station and a subscriber unit to have two pseudo-random code generators which can be clocked separately. Alignment of the uplink and downlink pseudo-random spreading codes is achieved by truncating the code sequence for the lower speed link at the conclusion of a complete code sequence for the higher speed link.Type: ApplicationFiled: April 30, 2010Publication date: August 19, 2010Applicant: INTERDIGITAL TECHNOLOGY CORPORATIONInventor: Fatih Ozluturk
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Patent number: 7778352Abstract: A polar transmitter includes a digital processor coupled to receive a complex modulated digital signal and a feedback signal produced from the complex modulated digital signal and that is operable to compare the complex modulated digital signal to the feedback signal to determine an error signal indicative of a difference between the complex modulated digital signal and the feedback signal. The digital processor is further operable to produce a correction signal from the error signal and to add the correction signal to the complex modulated digital signal to produce a corrected complex modulated digital signal.Type: GrantFiled: December 21, 2006Date of Patent: August 17, 2010Assignee: Broadcom CorporationInventors: Henrik T. Jensen, Hooman Darabi, Alireza Zolfaghari
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Publication number: 20100202495Abstract: A transmitter has a portion that sets a parameter about the transmitter itself based on a parameter made to correspond to a condition for selecting a receiver with which the transmitter communicate with, a portion that generates a spread code based on the set parameter, and a sending portion that spreads transmit-data to form a spread signal by the generated spread code, and that sends the spread signal. The receiver has a portion that receives the signal transmitted by the transmitter, a portion that sets a parameter about the receiver itself based on the parameter made to correspond to the condition, a portion that generates a despread code based on the set parameter, a portion that performs a correlation computation of the received signal and the generated despread code, and a portion that selects a transmitter with which the receiver communicates, based on a result of the correlation computation.Type: ApplicationFiled: August 28, 2008Publication date: August 12, 2010Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kazunori Kagawa, Norimasa Kobori, Yukinori Fujita
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Patent number: 7773661Abstract: A method for monitoring a redundant (passive) transmitter, being, for example, part of a base station of a point-to-multipoint radio communications system transmits, during normal operation, a spread-spectrum signal over the redundant transmitter, the spread-spectrum signal being of low spectral power in comparison with data signals being transmitted by the active transmitter of the base station. One or more receivers are associated, for example, with terminal stations in communication with the base station and detect the presence of the spread-spectrum signal. If the spread-spectrum signal is not found to be present, the receivers provide an indication of this, and from this indication, a decision is made as to the integrity of the redundant transmitter.Type: GrantFiled: June 27, 2002Date of Patent: August 10, 2010Assignee: Ericsson ABInventors: Heike Hofmann, Thomas Alberty, Khaled Fazel, Volker Hespelt
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Patent number: 7773696Abstract: A transmitter is configured to transmit a time of arrival (TOA) message to a receiver applying a quadrature multiple frequency ranging (QMFR) algorithm for separating multiple path signal components. The transmitter includes (1) a modulator for generating a quasi-band limited minimum shift keyed (QBL-MSK) signal, (2) a serial formatter for generating a serial QBL-MSK (SQBL-MSK) signal, and (3) a switch for disabling the serial formatter, during a time that the TOA message is being transmitted to the receiver.Type: GrantFiled: December 22, 2006Date of Patent: August 10, 2010Assignee: ITT Manufacturing Enterprises, Inc.Inventor: Donald John Rasmussen
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Patent number: 7773659Abstract: Disclosed herein is an Ultra WideBand (UWB) M-ary Code Shift Keying (MCSK)/Binary Pulse Position Modulation (BPPM) wireless communication system and method. The system includes a transmitter and a receiver. The transmitter selects a specific TH code using MCSK according to an additional data stream, performs BPPM on a desired signal according to the selected TH code, and transmits the modulated signal via a channel. The receiver receives the signal transmitted from the transmitter via the channel, and estimates the transmitted signal, which is transmitted from the transmitter, through detection of a Maximum Likelihood (ML) sequence.Type: GrantFiled: June 20, 2005Date of Patent: August 10, 2010Assignees: INHA-Industry Partnership Institute, Simon Fraser UniversityInventors: Dong In Kim, Serhat Erkucuk, Kyung Sup Kwak
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Patent number: 7769077Abstract: A diversity transmitting/receiving apparatus and method is provided, which is implemented using space-time trellis codes (STTC) constructed from a Pseudo Noise (PN) sequence set in a Direct Sequence (DS) CDMA system. The transmitter comprises a PN sequence generator, a space-time encoder, first and second modulators, and first and second multiple transmit antennas. The space-time encoder selects two of the multiple PN sequences to construct STTC, and space-time encodes data from a data source according to the STTC to output an Wary data symbol. The two modulators modulate the space-time encoded data according to the STTC. The two multiple transmit antennas wirelessly transmit outputs of the two modulators, respectively. By applying a method using space-time coding in a DS CDMA system including multiple transmit antennas, it is possible to achieve both diversity and additional coding gain and also to reduce multiple user interference by increasing the PN sequence length.Type: GrantFiled: December 21, 2004Date of Patent: August 3, 2010Assignee: Electronics and Telecommunications Research InstituteInventors: Dong-Woon Bai, Woo-Yong Lee, Hyun-Seo Oh
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Patent number: 7764725Abstract: A wireless communication system performs high-speed transmission of information signals by using a multi-band approach. Each band spans about 500MHz. A flexible modulation scheme within each band employs time, amplitude and phase modulations, allowing adaptation of the data rate to the sub-band conditions. In addition, pseudo-random frequency sequence is employed to provide sufficient multi-user interference reduction.Type: GrantFiled: February 10, 2004Date of Patent: July 27, 2010Assignee: Koninklijke Philips Electronics N.V.Inventor: Dagnachew Birru
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Publication number: 20100183052Abstract: Provided is a method and apparatus for transmitting and receiving a signal in a multi-antenna communication system. A method of transmitting a signal via a multipath channel in the multi-antenna communication system may include: generating continuous orthogonal spreading codes; spread-modulating a user signal using the continuous orthogonal spreading codes to generate a spread signal; performing pre-rake combining of the spread signal to generate a pre-rake synthesized signal; and transmitting the pre-rake synthesized signal via multiple antennas.Type: ApplicationFiled: November 24, 2009Publication date: July 22, 2010Applicant: Electronics and Telecommunications Research InstituteInventor: Kyeong Mun Geon
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Publication number: 20100183051Abstract: A spread spectrum cellular network (FIG. 1) mobile unit transmitter (30) that enables communication via protocols having different bandwidth (372) and baseband signal generation (260), the transmitter including a phase locked loop and an amplitude control loop.Type: ApplicationFiled: May 22, 2006Publication date: July 22, 2010Inventor: Mihai Margarit
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Patent number: 7760813Abstract: By assigning a plurality of subcarriers 31 to a data channel 33 and assigning fewer subcarriers 32 than the plurality of subcarriers 31 to a control channel 34, and in addition locating the control channel 34 at the center frequency fc of a frequency band used to transmit the data channel 33, on the radio receiving apparatus side, the frequencies of a local signal by which the received signal is multiplied share the same value, thereby speeding up the switching between the control channel and the data channel.Type: GrantFiled: April 2, 2008Date of Patent: July 20, 2010Assignee: Panasonic CorporationInventor: Kenichi Miyoshi
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Patent number: 7760698Abstract: A forward link design is provided employing CDMA (code division multiple access) technologies in which time division multiplexing is employed between data and control information on the forward link to service multiple users per slot. Another forward link design employing CDMA (code division multiple access) technologies is provided in which code division multiplexing between data and control information is employed on the forward link to service multiple users per slot, which is preferably backwards compatible with legacy standards such as IS2000A. A reverse link design is also provided.Type: GrantFiled: October 13, 2006Date of Patent: July 20, 2010Assignee: Alcatel LucentInventors: Xixian Chen, Neil N. McGowan, Muhammad Khaled Islam, Ning Guo, Hong Ren, Litong Li
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Patent number: 7756219Abstract: A WLAN transmitter capable of transmitting data signals modulated in accordance with an individual one of at least two different modulation schemes and corresponding methods and integrated circuit chips are provided. The WLAN transmitter contains a front end section having a low-IF topology and including a digital front end unit and an analog front end unit. The digital front end unit contains a first signal processing branch for processing transmission data signals modulated in accordance with a first one of said at least two different modulation schemes. The digital front end unit further contains a second signal processing branch for processing transmission data signals modulated in accordance with a second one of said at least two different modulation schemes. The analog front end unit contains one single signal processing branch for processing transmission data signals modulated in accordance with any one of said at least two different modulation schemes.Type: GrantFiled: July 14, 2005Date of Patent: July 13, 2010Assignee: GLOBALFOUNDRIES Inc.Inventors: Sascha Beyer, Wolfram Kluge, Michael Schmidt
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Publication number: 20100172395Abstract: Systems and methodologies are described that facilitate synthesizing a single baseband waveform from digital signals related to multiple carriers. Digital signals can be received relating to a plurality of carriers. The digital signals can result from spreading data symbols from transport blocks to create chip sequences, which can additionally be pulse shaped. The digital signals can be rotated in a positive or negative direction, such as according to a complex sinusoid or a negative representation thereof. The rotated signals can be combined or added to generate a single baseband waveform. The single baseband waveform can be converted to an analog signal, which can be up-converted and centered at a plurality of frequency carriers, which can be adjacent, assigned for transmitting the signal. In addition, optimizations can be provided to ensure threshold power ratio over the plurality of carriers for effectively transmitting jointly encoded signals.Type: ApplicationFiled: January 4, 2010Publication date: July 8, 2010Applicant: QUALCOMM, IncorporatedInventors: Sharad D. Sambhwani, Zae Yong Choi, Heechoon Lee, Arjun Bharadwaj
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Publication number: 20100172394Abstract: Provided are a method and apparatus for transmitting and receiving a signal at a variable data rate in human body communications. The apparatus includes a header generator, a data generator, a spreader, and a multiplexer. The header generator generates header information including a data rate. The data generator generates transmission data by repeating each data bit to be transmitted 0 to several times according to the data rate. The spreader spreads the transmission data using a spreading code in a desired frequency band. The multiplexer multiplexes the header information and the spread data.Type: ApplicationFiled: May 27, 2008Publication date: July 8, 2010Applicant: Electronics and Telecommunications Research InstituteInventors: In-Gi Lim, Hyung-Il Park, Tae-Wook Kang, Sung-Weon Kang, Jung-Hwan Hwang, Chang-Hee Hyoung, Kyung-Soo Kim, Jung-Bum Kim, Duck-Gun Park, Sung-Eun Kim, Jin-Kyung Kim, Park Ki-Hyuk
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Publication number: 20100165828Abstract: Methods for code-division multiplex communications. The method involve generating orthogonal or statistically orthogonal chaotic spreading codes (CSC1, . . . , CSCK) having different static offsets using a set of polynomial equations (f0(x(nT)), . . . , fN?1(x(nT)) and/or f0[x((n+v)T+t)], . . . , fN?1[x((n+v)T+t)]). The methods also involve forming spread spectrum communications signals respectively using the orthogonal or statistically orthogonal chaotic spreading codes. The methods further involve concurrently transmitting the spread spectrum communications signals over a common RF frequency band. The spreading codes are generated using different initial values for a variable “x” of a polynomial equation f(x(nT)) and/or different acc-dec values for a variable “v” of a polynomial equation f[x((n+v)T+t)]. The static offsets are defined by the different initial values for a variable “x” and/or different acc-dec values for a variable “v”.Type: ApplicationFiled: December 29, 2008Publication date: July 1, 2010Applicant: Harris CorporationInventors: Alan J. Michaels, David B. Chester
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Publication number: 20100166043Abstract: A MC-CDMA transmitter and an MC-CDMA receiver are provided, which use a novel orthogonal spreading code that allows an effect by a delay wave to appear in only a specific user. An MC-CDMA system includes: a transmitter which multiplies a transmitting signal by a sinusoidal signal which has an amplitude of r and is orthogonal as a result that the frequency periods are different among users, in a frequency domain to be spread and split into orthogonal sub-carriers, and multiplexes the sub-carriers; and a receiver for receiving a transmitting signal from the transmitter in a manner that a sinusoidal signal, which has an amplitude of r and is orthogonal as a result that the frequency periods are different among users, is multiplied by the transmitting signal in a frequency domain, and the resultant is inversely spread.Type: ApplicationFiled: January 17, 2007Publication date: July 1, 2010Inventors: Hideichi Sasaoka, Hisato Iwai, Yusuke Miyamoto
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Publication number: 20100166041Abstract: Methods for code-division multiplex communications. The methods involve generating orthogonal or statistically orthogonal chaotic spreading codes (CSC1, . . . , CSCK) using different sets of polynomial equations (f0(x(nT)), . . . , fN-1(x(nT))), different constant values (C0, C1, . . . , CN-1) for the polynomial equations, or different sets of relatively prime numbers (p0, p1, . . . , pN-1) as modulus (m0, m1, . . . , mN-1) in solving the polynomial equations. The methods also involve forming spread spectrum communications signals using the orthogonal or statistically orthogonal chaotic spreading codes, respectively. The method further involve concurrently transmitting the spread spectrum communications signals over a common RF frequency band.Type: ApplicationFiled: December 29, 2008Publication date: July 1, 2010Applicant: Harris CorporationInventors: Alan J. Michaels, David B. Chester
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Patent number: 7746916Abstract: A method of generating a code sequence in a wireless communication system is disclosed. More specifically, the method includes recognizing a desired length of the code sequence, generating a code sequence having a length different from the desired length, and modifying the length of the generated code sequence to equal the desired length. Here, the step of modifying includes discarding at least one element of the generated code sequence or inserting at least one null element to the generated code sequence.Type: GrantFiled: November 28, 2006Date of Patent: June 29, 2010Assignee: LG Electronics Inc.Inventors: Seung Hee Han, Min Seok Noh, Yeon Hyeon Kwon, Hyun Hwa Park, Hyun Woo Lee, Dong Cheol Kim
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Patent number: 7742517Abstract: A modulator includes a first input configured to input a first bit string; a first modulating device configured to modulate the inputted first bit string at a first bit rate; a second input configured to input a second bit string; a second modulating device configured to modulate the inputted second bit string at a second bit rate which is lower than the first bit rate; and an output configured to output a modulated signal including the modulated first bit string and the modulated second bit string.Type: GrantFiled: February 24, 2006Date of Patent: June 22, 2010Assignee: Kabushiki Kaisha ToshibaInventors: Koji Akita, Tomoya Horiguchi, Koji Ogura
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Patent number: 7742516Abstract: A modulator, and more particularly an HPSK modulator, is disclosed that enables the circuit scale to be reduced and also enables power consumption to be reduced. An HPSK modulator 209 incorporated in a radio communication apparatus or the like is equipped with a spreading code multiplication section 11, a complex arithmetic section 101, a coefficient determination section 51, and raised COS filters 41 and 42. Spreading code multiplication section 11 multiplies transmit data DPDCH1 by a spreading code Cd1. Complex arithmetic section 101 performs complex arithmetic on an output signal output from spreading code multiplication section 11 and a scrambling code Sn, and performs conversion to complex data. Coefficient determination section 51 determines a filter coefficient Ad1n based on a gain factor ?d1 that determines transmission power. Raised COS filters 41 and 42 band-limit the complex data using the filter coefficient.Type: GrantFiled: July 1, 2005Date of Patent: June 22, 2010Assignee: Panasonic CorporationInventors: Masahiko Sagisaka, Yusaku Tada
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Patent number: 7742543Abstract: A transmission circuit alleviates the frequency characteristics of a group delay and an attenuation amount in a transmission signal band and expands a dynamic range to a high frequency band. A ladder-type resistance-type attenuator includes switching elements, 2R resistor elements and R resistor elements. The 2R and R resistor elements are respectively connected to variable capacitor elements in parallel. The variable attenuator having such a connection structure is connected to an amplitude modulation loop of the transmission circuit. By controlling the capacitance value of the variable capacitor elements using the capacitance value control section when the switching elements are ON/OFF switched based on the transmission power control signal, the influence of parasitic capacitances of the variable capacitor elements is suppressed and the group delay between the amplitude modulation and the phase modulation is reduced.Type: GrantFiled: January 3, 2007Date of Patent: June 22, 2010Assignee: Panasonic CorporationInventor: Masakatsu Maeda
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Publication number: 20100150211Abstract: A plurality of data signals are separated into parallel bit streams with each parallel stream having a bandwidth characteristic such that the combined cumulative effect of all the individual bandwidths produces a spectral characteristic of the data signals that match the spectral high speed data characteristic of a twisted pairType: ApplicationFiled: December 29, 2009Publication date: June 17, 2010Inventors: Diakoumis Parissis Gerakoulis, Evaggelos Geraniotis
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Patent number: 7738528Abstract: A generator of repetitive sets of spreading sequences includes an element for counting and for forming an address and a table containing L sets of S sequences. The address contains q+log2S bits. The q bits are used for selecting one set among L (L=2q) sets. The log2S bits are used for selecting one sequence among the S sequences in the set.Type: GrantFiled: July 31, 2006Date of Patent: June 15, 2010Assignee: Commissariat a l'Energie AtomiqueInventors: Norbert Daniele, Dominique Noguet, Rosolino Lionti, Jean-René Lequepeys
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Publication number: 20100142595Abstract: A communication system generates a continuously orthogonal spreading code for a user, a user signal is spreading-modulated by using the continuously orthogonal spreading codes, and then the spread signal is pre-rake combined and transmitted. A receiver processes the received signal by using a matched filter for one path.Type: ApplicationFiled: November 30, 2007Publication date: June 10, 2010Applicant: Electronics and Telecommunications Research InstituteInventors: Mun-Geon Kyeong, Woo-Goo Park, In-Cheol Jeong, Jae-Sang Cha
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Publication number: 20100142592Abstract: A wireless network (20) with at least a first radio communication unit (24) and a second radio communication unit (26) transmits and receives signals with minimal interference from the surrounding environment of the first unit (24) and second unit (26). The first radio communication unit (24) determines frequencies (54) having power level above a threshold (52), and creates a list of these frequencies (50) to be transmitted to the second radio communication unit (26). The second radio communication unit (26) places notches (140) in its transmission band (88) based on frequencies (54) in the list (50), reserved frequencies (132), and local frequencies (92) having signal energy above a threshold (90). When transmitting a signal (42), the second radio communication unit (26) avoids transmitting in frequencies that have notches (140).Type: ApplicationFiled: December 9, 2008Publication date: June 10, 2010Applicant: General Dynamics C4 Systems, Inc.Inventors: Scott David Blanchard, Randall K. Bahr
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Patent number: 7729410Abstract: A system for and method of converting successive bits of digital data into BPSK symbols using one or more BPSK symbol constellations such that orthogonal BPSK constellations are referenced to successive bits of the digital data. The system and method may toggle between referencing first and second orthogonal constellations as successive bits of the digital data are encountered. Alternatively, the system and method may successively rotate by 90° the constellation to be referenced as successive bits of the digital data are encountered. The reversal of the systems and methods described can be used to decode a transmission made by the methods described or specifically to reference a succession of orthogonal BPSK constellations to convert a succession of BPSK symbols to a succession of bits of digital data. Furthermore, a standard quadrature receiver can be used to perform the conversion.Type: GrantFiled: March 31, 2008Date of Patent: June 1, 2010Assignee: NXP B.V.Inventor: Donald Brian Eidson
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Patent number: 7729409Abstract: Apparatuses for achieving high bit densities in a direct-sequence CDMA spread spectrum communication system are disclosed. A table of orthogonal pseudo-noise codes is stored. This table is then partitioned into multiple codebook. Then, the codebook is assigned to a user. The pseudo-noise code contained within the codebooks are used to spread information signal. Information signal for a first user is spread by a pseudo-noise code contained within the codebook assigned to the first user. Multiple bits of information signal may be sent at a time by using the location of the pseudo-noise code within the codebook such that the value of the information signal corresponds the location of the pseudo-noise code within the codebook. The information signal is then despread by using the same pseudo-noise code.Type: GrantFiled: October 30, 2007Date of Patent: June 1, 2010Assignee: Intel CorporationInventor: David Horne
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Patent number: 7729408Abstract: A spread spectrum slip time encoding scheme encodes data values with one or more Pseudo Noise (PN) codes and generates a corresponding PN encoded data stream. Other data values are encoded into the PN encoded data stream by varying a slip time between the PN-encoded data values.Type: GrantFiled: February 9, 2004Date of Patent: June 1, 2010Assignee: Cypress Semiconductor CorporationInventors: Robert Mack, Stephen O'Connor
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Publication number: 20100128757Abstract: Sequence generation in wireless communication is provided for sequences having good aperiodic correlation properties. In particular, dual window quasi-Barker sequences are generated that possess at least some properties of Barker sequences. In addition, the sequences can be orthogonal to mitigate multiple access interference. Dual windowing allows the sequences even after being phase modulated by data to be recognized, provided that delay in transmission is large as compared to the correlation zone. In this regard, the sequences can be utilized in quasi-synchronous spread spectrum and/or code division multiple access (CDMA) signal communication to provide orthogonality while substantially eliminating inter-user and inter-symbol interference. In addition, unlike the single window low periodic correlation sequences, system overheads, such as cyclic prefix, need not be utilized in transmission as the data modulation effect can be accounted for by the dual windowing.Type: ApplicationFiled: February 12, 2009Publication date: May 27, 2010Applicant: THE HONG KONG UNIVERSITY OF SCIENCE AND TECHNOLOGYInventors: Wei Hsiang Wu, Ho Yin Chan, Wai Ho Mow
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Patent number: 7724805Abstract: A system and method are provided for quickly measuring the Root Mean Square (RMS) value of digital quadrature signals (I, Q) input to a Wideband Code Division Multiple Access (W-CDMA) transmitter. In general, in a W-CDMA transmitter such as that in a Universal Mobile Telecommunications System (UMTS), multiple channels are combined to provide the digital quadrature signal (I, Q) input to the transmitter. The RMS value of the digital quadrature signal (I, Q) may be determined using a number of consecutive samples of the digital quadrature signal (I, Q) over a period corresponding to mutually orthogonal segments of the spreading codes used for the transmitted channels. As a result of the mutual orthogonality of the segments of the spreading codes, a residual error of the RMS measurement is equal to zero, thereby providing an accurate RMS measurement in much less time than required by traditional RMS measurement schemes.Type: GrantFiled: September 6, 2006Date of Patent: May 25, 2010Assignee: RF Micro Devices, Inc.Inventors: Nadim Khlat, David Myara
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Patent number: 7720497Abstract: Method and apparatus for determining a transmission configuration for a dedicated channel in a wireless communication system. In one embodiment, an optimum configuration is determined based on minimizing Peak-to-Average Ratio (PAR) of the channel. The configuration is defined as a transmission pair of transmission branch and spreading code. The transmission branch may be the In-Phase (I) branch or the Quadrature (Q) branch. PAR analysis may be performed off-line to determine the optimum configuration. In operation, if the spreading code of the optimum configuration is used by another channel, the next best optimum code is used.Type: GrantFiled: February 14, 2006Date of Patent: May 18, 2010Assignee: QUALCOMM IncorporatedInventor: Serge Willenegger
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Publication number: 20100118920Abstract: Satellite communication transmitter and receiver in a DVB-S2 system are provided. The satellite communication transmitter includes a modulator to modulate a satellite communication signal to be transmitted, and a spread spectrum unit to spread the modulated signal and transmit the spread signal. Accordingly, it is possible to reduce interference with a neighboring channel.Type: ApplicationFiled: August 6, 2009Publication date: May 13, 2010Applicant: Electronics and Telecommunications Research InstituteInventors: Pan-soo KIM, Dae-ig CHANG, Ho-jin LEE, A. VANELLI-CORALLI, G.E. CORAZZA, C. PALESTINI, R. PEDONE, M. VILLANTI
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Patent number: 7715502Abstract: A low-power pulse generator is provided for use in ultra-wideband (UWB) systems. In one embodiment, the UWB pulse generator includes four pulse generators, such as digital triangular pulse generators, that generate Gaussian-like pulses of alternating polarity at different time offsets. The resulting four Gaussian-like pulses are combined to generate a UWB pulse that approximates the fifth derivative of a Gaussian pulse. In other embodiments, different-order derivatives of a Gaussian pulse may be approximated by combining different numbers of Gaussian-like pulses. The UWB pulse generator is preferably implemented with CMOS circuitry to limit power consumption.Type: GrantFiled: September 7, 2006Date of Patent: May 11, 2010Assignee: Arizona Board of RegentsInventors: Hyunseok Kim, Youngjoong Joo
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Patent number: 7715461Abstract: Method and apparatus for high rate code-division multiple access wireless communication is described. Each of a channel encoded data is modulated by an associated code having a small number of pseudo-noise spreading chips per orthogonal waveform period, thus producing a set of streams of modulated symbols. Each of the set of streams of modulated symbols is then gain adjusted, and combined to yield two streams of combined symbols. The combination is the set of streams is carried out to reduce a peak-to-average ratio of the transmission. The resulting two combined symbol streams are modulated by a complex multiplier using a user long code and a pseudorandom spreading code (PN code) and upconverted for transmission.Type: GrantFiled: January 13, 2004Date of Patent: May 11, 2010Assignee: Qualcomm, IncorporatedInventor: Joseph P. Odenwalder
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Publication number: 20100111142Abstract: Disclosed are a radio transmission device and a radio transmission method which can reduce a processing amount or a memory amount while maintaining the randomizing effect of other cell interference. When using as a reference signal, a ZC sequence of the sequence length uniquely correlated to a transmission bandwidth of a reference signal, as the transmission bandwidth becomes smaller and the sequence length of the ZC sequence becomes shorter, the sequence is switched at a shorter time interval and as the transmission bandwidth becomes greater and the sequence length of the ZC sequence becomes longer, the switching is performed at a longer time interval. Thus, a reference signal is generated by using the ZC sequence in accordance with the timing into which the reference signal transmission bandwidth and the sequence are switched.Type: ApplicationFiled: March 14, 2008Publication date: May 6, 2010Applicant: PANASONIC CORPORATIONInventors: Takashi Iwai, Daichi Imamura, Sadaki Futagi, Yoshihiko Ogawa, Tomofumi Takata, Atsushi Matsumoto
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Patent number: 7711033Abstract: The present invention provides a method and apparatus for generating SIR estimates early in a time interval that include the benefits of interference suppression without requiring the computation of specific interference suppression elements. In particular, the present invention generates an SIR estimate for a RAKE receiver during a current time interval based on channel estimates generated based on the received signal(s). By applying an offset derived during a previous time interval to the RAKE SIR estimate, the present invention generates a second SIR estimate for a G-RAKE receiver.Type: GrantFiled: April 14, 2005Date of Patent: May 4, 2010Assignee: Telefonaktiebolaget LM Ericsson (publ)Inventors: Andres Reial, Douglas A. Cairns
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Patent number: 7711032Abstract: The frequency spectrum of a transmitter system is spreaded in the transmitter (1) through the codification of information bits by means of sequence pairs of Golay complementary sequences. The spectrum is received in the receiver (2) and is subject to a filter, which is adapted to the features of such sequences enabling the detection of digital levels corresponding to the original transmitted information. If pairs of orthogonal sequences, A amplitudes for moduling data, and N-PSK modulation are used, it is possible to get a transmission speed (C) equal to: Where B is to the null-to-null spread bandwidth used in Hertz. It allows an improvement in quality as compared to other digital-communication systems, which use spread spectrum techniques and CDMA, obtaining a process gain independent of the transmission speed.Type: GrantFiled: April 27, 2001Date of Patent: May 4, 2010Assignee: Vicente Diaz FuenteInventor: Vicente Diaz Fuente