End-to-end Transmission System Patents (Class 375/141)
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Publication number: 20100208770Abstract: An arrangement (90) for noise rise estimation in a wireless communication system comprises a power measuring means (45) for measuring received total wideband power. A means (52) for computing estimates of a noise floor measure bases its computation on a number of the measured received total wideband powers. A means (80) for calculating values of a biased noise rise measure bases its calculations on a number of received total wideband powers or an estimation derived therefrom and a respective one of the estimates of a noise floor measure. A means (91) for providing a measure representing a long term behaviour of the values of the biased noise rise measure is provided. A means (93) for obtaining a value of a present, unbiased noise rise measure, bases its function on the measure representing a long term behaviour of the values of the biased noise rise measure. A corresponding method is also disclosed.Type: ApplicationFiled: September 19, 2007Publication date: August 19, 2010Inventor: Karl Torbjörn Wigren
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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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Patent number: 7778377Abstract: Methods and apparatus are provided for generating a frequency with a predefined offset from a reference frequency. A spread spectrum generator circuit is disclosed that comprises a voltage controlled delay loop for generating a plurality of signals having a different phase; and at least one interpolator for processing at least two of the signals to generate an output signal having a phase between a phase of the at least two of the signals, wherein the output is varied between a phase of the at least two of the signals to generate the spread spectrum. A spread spectrum having a frequency lower than an applied clock signal is generated using a continuous phase delay increase and a spread spectrum having a frequency higher than the clock signal is generated using a continuous phase delay decrease.Type: GrantFiled: May 31, 2005Date of Patent: August 17, 2010Assignee: Agere Systems Inc.Inventors: Vladimir Sindalovsky, Lane A. Smith, Craig B. Ziemer
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Patent number: 7769079Abstract: In a code division multiple access communication system (100), a method and an accompanying apparatus provide for an efficient control of a gain level of a communication channel at various mobility levels. A rate of change of a carrier to interference ratio (C/I) of a communication channel received at a receiver (400) is determined. The gain level of the communication channel may be based on the rate of change of the C/I of the communication channel. A mobility level of the communication channel may be compared to a low mobility threshold corresponding to a low mobility level. If the mobility level meets the low mobility threshold, the gain level of the communication channel may be based on the rate of change of the C/I of the communication channel.Type: GrantFiled: October 5, 2006Date of Patent: August 3, 2010Inventor: Yu-Cheun Jou
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Publication number: 20100189162Abstract: A transmission-and-reception apparatus of the present invention includes: a receiver that receives category information concerning a function of another transmission-and-reception apparatus; a selector that selects an interleaving scheme based on the category information; and an interleaver that interleaves signals to be transmitted to the other transmission-and-reception apparatus based on the selected interleaving scheme. Thereby, the maximum performance of each reception apparatus can be achieved even when reception apparatuses belonging to multiple categories are included in a wireless communication system.Type: ApplicationFiled: September 5, 2007Publication date: July 29, 2010Inventors: Takashi Yoshimoto, Ryota Yamada, Toshizo Nogami
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Publication number: 20100177804Abstract: A method of transmitting a control signal in a wireless communication system includes allocating a first sequence to spread a first control signal in a radio resource, allocating a second sequence to spread a second control signal in the radio resource, selecting one of the first control signal and the second control signal, generating a spread control signal by spreading the selected control signal, and transmitting the spread control signal in the radio resource, wherein the first sequence and the second sequence use different cyclic shifts of a base sequence.Type: ApplicationFiled: May 30, 2008Publication date: July 15, 2010Inventors: Jin Sam Kwak, Seung Hee Han, Min Seok Noh, Yeong Hyeon Kwon, Hyun Woo Lee, Dong Cheol Kim
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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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Patent number: 7756193Abstract: A method for operating a Radio Frequency (RF) receiver of a wireless terminal. During a first time interval, an RF front end is enabled and the RF receiver receives and processes an RF signal, e.g., a Wideband Code Division Multiple Access (WCDMA) signal, to produce a baseband signal and to store samples of the baseband signal. During a second time interval that differs from the first time interval, the RF front end is disabled and the RF receiver processes the plurality of samples of the baseband signal of the first time interval to measure signal strengths of a plurality of pilot signals present in the baseband signal of the first time interval. Finally, during a third time interval that differs from the first time interval and the second time interval, the RF front end is enabled and the RF receiver receives and processes an RF signal of the third time interval to extract data there from. Memory is shared between the first, second, and third time intervals for different uses.Type: GrantFiled: September 21, 2006Date of Patent: July 13, 2010Assignee: Broadcom CorporationInventors: Louis Jacobus Botha, Frederic Christian Marc Hayem, Hendrik Johannes Conroy
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Patent number: 7756000Abstract: A system for communicating includes a transmitter that has an encoder and baseband modulator that encodes and modulates a sequence of data symbols as a payload data constellation to be communicated. A PN sequence generator and baseband modulator form a pilot signal as a training sequence with a periodically repeating spread spectrum sequence. A circuit superimposes the pilot signal over the sequence of data symbols to form a composite communication signal that is transmitted. A receiver receives the composite communication signal and extracts the pilot signal from the composite communication signal.Type: GrantFiled: May 17, 2007Date of Patent: July 13, 2010Assignee: Harris CorporationInventors: David B. Chester, David H. Damerow
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Publication number: 20100164941Abstract: A spread spectrum clocking interface apparatus of a flat panel display for compensating for a frequency difference between a first clock signal externally supplied to a timing controller and a second clock signal generated from a spread spectrum clocking unit. The spread spectrum clocking interface apparatus includes a storage unit, first and second counters, and a delay unit. The storage unit stores input data to be supplied to the flat panel display in a first-in/first-out (FIFO) manner in accordance with a write address and outputs the stored input data in the FIFO manner in accordance with a read-out address. The first counter counts the first clock signal in response to a display enable signal and outputs a result of the counting as the write address. The delay unit delays the display enable signal while the second counter counts the second clock signal in response to the delayed display enable signal and outputs a result of the counting of the second counter as the read-out address.Type: ApplicationFiled: December 11, 2009Publication date: July 1, 2010Inventor: Jong-Seok Chae
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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: 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: 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: 7746919Abstract: A modified adaptive minimum mean square error (MMSE) receiver detects a spread spectrum signal, minimizing interference among multiple users. The receiver receives multiple pilot bits and corresponding data bits. A channel is estimated using at least one of the received pilot bits and, simultaneously, the data bits are detected based on the pilot bit and an inverse of a gain of the receiver. The spectrum signal may be spread in accordance with a wideband code division multiple access (W-CDMA) format, in which the pilot bits are modified to include a predetermined bit sequence of alternating ones and negative ones.Type: GrantFiled: November 8, 2006Date of Patent: June 29, 2010Assignee: AT&T Intellectual Property I, L.P.Inventor: Arunabha Ghosh
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Patent number: 7742775Abstract: A method of determining the location of a communication tag in a random phase multiple access communication network is disclosed. A ranging request signal that is spread using a first pseudo-noise code and offset with a first random timing offset is transmitted at a first time. A ranging response signal that is spread using a second pseudo-noise code and offset with a second random timing offset is received at a second time. A propagation delay that is dependent on the first time and the second time is calculated.Type: GrantFiled: June 12, 2009Date of Patent: June 22, 2010Assignee: On-Ramp Wireless, Inc.Inventor: Theodore J. Myers
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Publication number: 20100150210Abstract: A wireless communication apparatus in a closed loop communication wherein a channel resource can be shared among users and hence the capacity of the communication system can be increased.Type: ApplicationFiled: September 29, 2006Publication date: June 17, 2010Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.Inventors: Zheng Zhao, Jifeng Li
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Patent number: 7738531Abstract: A GPS communication system including a server and a client, each including a GPS receiver, for reducing the code phase search space of the GPS receiver of the client. The communication system includes a transmitter for transmitting timing information from the server to the client to help the client locate a first satellite, and a receiver for using timing differences between the satellites to synchronize and locate other satellites. The code phase search space is reduced by reducing the number of phase hypotheses that must be calculated to establish communication between the server and the client.Type: GrantFiled: May 5, 2008Date of Patent: June 15, 2010Assignee: QUALCOMM IncorporatedInventor: Christopher Patrick
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Patent number: 7738540Abstract: A wireless transmission system capable of performing a multi-station simultaneous transmission of data, that is, simultaneously transmitting data by wireless to a plurality of stations. The wireless transmission system includes a plurality of wireless stations for transmitting/receiving data and it constitutes a system for path diversity by use of a wireless station at the transmitting end, a multipath transmission path, and a wireless station at the receiving end. At least one of the plurality of wireless stations decides, in accordance with a response packet responsive to a multi-station simultaneous transmission request packet transmitted by the wireless station or other stations, a plurality of delay amounts relative to a reference timing during the multi-station simultaneous transmission in the wireless transmission system.Type: GrantFiled: September 26, 2005Date of Patent: June 15, 2010Assignee: Panasonic CorporationInventors: Hidetoshi Yamasaki, Hitoshi Takai, Hideki Nakahara, Kenji Miyanaga
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Publication number: 20100142589Abstract: The multi-carrier code dividing multiplex transfer system of the present invention includes a direct demodulator that discriminates transmitted signals according to a receiving signal point composed of a combination of receiving values in a spread state of sub-carriers in a range where one modulated symbol is spread, and according to reference signal composing values that can be taken by the combination of the receiving values in the spread state of the sub-carriers. As a result, it is possible to prevent from affects of inter-code interference, and improve receiving characteristics as well.Type: ApplicationFiled: September 28, 2006Publication date: June 10, 2010Applicant: KDDI CORPORATIONInventors: Toshinori Suzuki, Noriaki Miyazaki
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Publication number: 20100142590Abstract: A method comprising: selecting an available orthogonal spreading code from a set of orthogonal spreading codes that are used for separating overlapping radio transmissions in a spread spectrum multiple access communication system; spreading a predetermined sequence using the selected spreading code; transmitting the spread predetermined sequence as a calibrating radio transmission; detecting a calibration signal corresponding to the calibrating radio transmission; and using the detected calibration signal to modify subsequent radio transmissions within the spread spectrum multiple access communication system.Type: ApplicationFiled: December 8, 2006Publication date: June 10, 2010Inventors: Thomas Höhne, Gang Xu
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Publication number: 20100142591Abstract: Information symbols are transmitted simultaneously on independent streams using the same spreading code but from different transmit antennas at the transmitter. These simultaneous data stream could be intended for the same user (and thereby the data rate for any particular user can be increased) or for different users (thereby increasing the system capacity). Each stream of data can belong to a different signal constellation and use a different channel code. At the receiver, a number of receive antennas equal to at least the number of multiple data streams is used to separate the different data streams. We consider two different cases. The first one when no transmit diversity is used (this case can also include the case when transmit diversity with simple antenna weighting is used) and the second when transmit diversity with space-time block coding is used.Type: ApplicationFiled: October 26, 2009Publication date: June 10, 2010Applicant: INFINEON TECHNOLOGIES AGInventor: Ayman F. NAGUIB
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Patent number: 7733946Abstract: This invention concerns a terrestrial repeater (RF) dedicated to a hybrid communication network comprising a satellite for transmitting to terminals (and at least to the repeater) signals (SPI) in the form of a first modulated carrier with data to be transmitted, encoded by suing initial sequences of at least two pseudo-random codes, and spectrally spread with spreading codes each associated with a sequence.Type: GrantFiled: April 29, 2005Date of Patent: June 8, 2010Assignee: Alcatel LucentInventors: Michel-Guy Francon, Paul Vincent, Nicolas Chuberre
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Patent number: 7733939Abstract: A system for implementing an orthogonal frequency division multiplexing scheme and providing an improved range extension. The system includes a transmitter for transmitting data to a receiver. The transmitter includes a symbol mapper for generating a symbol for each of a plurality of subcarriers and a spreading module for spreading out the symbol on each of the plurality of subcarriers by using a direct sequence spread spectrum. The symbol on each of the plurality of subcarriers is spread by multiplying the symbol by predefined length sequences. The receiver includes a de-spreader module for de-spreading the symbols on each of the plurality of subcarriers. The de-spreader module includes a simply correlator receiver for obtaining maximum detection. The correlator produces an output sequence of a same length as an input sequence and the de-spreader module uses a point of maximum correlation on the output sequence to obtain a recovered symbol.Type: GrantFiled: November 3, 2005Date of Patent: June 8, 2010Assignee: Broadcom CorporationInventor: Jason Alexander Trachewsky
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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: 20100127831Abstract: An active radio frequency identification (RFID) apparatus having an additional transmitter in addition to a single transmitter is provided. The active RFID apparatus includes a first transmitter including a first pseudo noise (PN) code generator to generate a direct sequence spread spectrum (DSSS) introduced by ISO/IEC (International Organization for Standardization/International Electrotechnical Commission) 24730-2 or ISO/IEC 18185-5 type B; and a second transmitter including a second PN code generator to perform an AND operation on an initial value and a fed back value and shift the resultant value of the AND operation, to perform an XOR operation on particular bits from among the shifted bits and to perform an XOR operation again on the shifted bits and the resulting value of the XOR operation to finally generate a PN code.Type: ApplicationFiled: September 17, 2009Publication date: May 27, 2010Applicant: Electronics and Telecommunications Research InstituteInventors: Jong-sub CHA, Seung-il MYONG, Heyung-sub LEE, Sang-hyun MO, Jong-suk CHAE
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Patent number: 7724802Abstract: A radar apparatus includes a transmission section, a delay device, a reception section, a switch control section, a switching frequency detection section, and a relative distance calculation section. The transmission section transmits a signal wave, which is spectrum spread by using a spread code. The delay device gives delay to the spread code. The reception section receives a wave reflected by an object and spectrum despreads the reflected wave with using the delayed spread code to output a despread signal. The switch control section switches at a switching frequency an operation of at least one of the transmission section, the reception section, and the delay device. The switching frequency detection section detects the switching frequency from the despread signal. The relative distance calculation section calculates a distance to the object based on a detection result provided by the switching frequency detection section and an amount of the delay.Type: GrantFiled: September 23, 2004Date of Patent: May 25, 2010Assignee: Fujitsu Ten LimitedInventors: Kanako Honda, Osamu Isaji
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Publication number: 20100124206Abstract: A pilot channel signal for time-division multiplexing with one or more traffic channel signals in a broadcast/multi-cast signal and for code-division multiplexing with a continuously transmitted pilot channel signal is described. In an exemplary method for transmitting a broadcast/multicast signal, a pilot symbol sequence is obtained for each slot of one or more frames of the broadcast/multicast signal, so that the pilot symbol sequence varies for each slot of a given frame. The pilot symbol sequence for each slot is spread with a channelization code, and the spread pilot symbol sequence for each slot is scrambled, using a scrambling code, to form a first pilot channel signal. The first pilot channel signal is transmitted so that it is time-division multiplexed with one or more traffic channel signals transmitted during each slot and code-division multiplexed with a second pilot channel signal transmitted during all slots of the one or more frames.Type: ApplicationFiled: October 2, 2009Publication date: May 20, 2010Inventors: Gregory E. Bottomley, Dirk Gerstenberger, Lars Lindbom, Yi-Pin Eric Wang
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Patent number: 7720133Abstract: Disclosed is a wireless communication apparatus for receiving a code-spread transmission signal. The wireless communication apparatus includes: an RF section; and a baseband section, wherein, in the baseband section, despreaders of an integral submultiple, which is 1/n1, of the number of chips of a spread code are arranged in parallel, and there is provided a propagation measurement section that measures a propagation channel by using the plurality of despreaders a plurality of times in a time-division manner and performing despread of each period corresponding to a chip rate of the spread code.Type: GrantFiled: August 25, 2005Date of Patent: May 18, 2010Assignee: Sony CorporationInventors: Akihiro Koyama, Akira Hayashi, Shinsuke Tashiro, Tsuyoshi Hashimoto, Masayuki Takada, Katsumi Watanabe
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Patent number: 7720130Abstract: Transmit diversity (TD) has become a common technique used in modern wireless communications systems to improve performance. TD uses multiple antennas (e.g., 110 and 111) at a transmitter (e.g., 105) to transmit multiple encoded datastreams and a single (or multiple) antenna (e.g., 116) at a receiver (e.g., 115) to receive the datastreams. Preferred embodiments of the present invention provide a general architecture (e.g., 705) that can support different TD schemes and even non-TD, simplifying receiver design and minimizing hardware usage.Type: GrantFiled: August 28, 2002Date of Patent: May 18, 2010Assignee: Texas Instruments IncorporatedInventors: Yan Hui, Gibong Jeong
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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: 7711030Abstract: A method is described comprising: transmitting a training signal from each antenna of a base station to each of a plurality of client devices utilizing tropospheric scatter, each of the client devices analyzing each training signal to generate channel characterization data, and transmitting the channel characterization data back to the base station utilizing tropospheric scatter; storing the channel characterization data for each of the plurality of client devices; receiving data to be transmitted to each of the client devices; and precoding the data using the channel characterization data associated with each respective client device to generate precoded data signals for each antenna of the base station; and transmitting the precoded data signals through each antenna of the base station to each respective client device.Type: GrantFiled: October 21, 2005Date of Patent: May 4, 2010Assignee: Rearden, LLCInventor: Stephen G. Perlman
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Publication number: 20100103983Abstract: A base station is described herein that uses a root spreading code based code assignment to transmit signals to a mobile station. The mobile station can then suppress intra-block interference by effectively using a joint detection technique or a non-linear equalization technique to detect the transmitted symbols.Type: ApplicationFiled: October 29, 2008Publication date: April 29, 2010Inventors: Yi-Pin Wang, Gregory E. Bottomley
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Publication number: 20100103984Abstract: A frequency-division multiplexing transmission apparatus for transmitting data in a frequency spectrum specific to both symbol and mobile station, is disclosed. The apparatus encodes transmission data, modulates the encoded data, compresses the time domains of each symbol of the modulated transmission-symbol sequence, repeats the symbols a specified number of times, rearranges each of the symbols of the obtained repetitive-symbol sequence so that they have the same arrangement as the transmission-symbol sequence, generates each phase that changes at a speed specific to each symbol of the transmission-symbol sequence, performs phase rotation specific to the symbols for each symbol of the rearranged repetitive-symbol sequence, generates phase that changes at a speed specific to a mobile station, performs phase rotation specific to the mobile station for the symbol sequence for which the phase rotation was performed, and transmits the phase-rotated symbol sequence.Type: ApplicationFiled: November 11, 2009Publication date: April 29, 2010Applicant: FUJITSU LIMITEDInventor: Toshio Kawasaki
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Patent number: 7706428Abstract: Inter-carrier interference (ICI) in a kth sub-carrier of an orthogonal frequency division multiplexing (OFDM) signal received at time t is reduced, wherein the received OFDM signal comprises a plurality of sub-carriers. This is achieved by generating a self-interference term, ICIk?L,k?L, for a signal received on sub-carrier k?L, wherein L ? [ . . . , ?3,?2,?1,1,2,3, . . . ], and wherein the self-interference term is an estimate of the data received at time t on the sub-carrier k?L, weighted by a rate of change of the channel through which sub-carrier k?L passes at time t. An ICI cancellation coefficient, GL is obtained, and an estimated ICI term is generated by adjusting the self-interference term, ICIk?L,k?L, by an amount based on the ICI cancellation coefficient, GL. The estimated ICI term is then subtracted from a term representing a signal received on the kth sub-carrier at time t.Type: GrantFiled: February 10, 2006Date of Patent: April 27, 2010Assignee: Telefonaktiebolaget L M Ericsson (publ)Inventors: Leif Wilhelmsson, Michael Faulkner
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Publication number: 20100098135Abstract: Apparatuses and methods for avoiding interference between wireless systems are described herein. One embodiment of the disclosure provides an apparatus for avoiding interference between at least one transmitter and at least one receiver within at least one wireless device. The apparatus comprises a first processing circuit configured to determine whether one or more bins are affected by interference from a transmitter based on predetermined information.Type: ApplicationFiled: October 15, 2009Publication date: April 22, 2010Applicant: QUALCOMM IncorporatedInventor: Alecsander P. Eitan
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Patent number: 7701998Abstract: Positioning of a mobile signal transmitter. A respective distance between the transmitter and each of a plurality of sensors is determined based on a direct sequence spread spectrum signal. A transmission delay of the signal is estimated with high accuracy by, in each sensor, cross-correlating an over-sampled representation of the signal with an appropriate local spreading sequence, which contains poly-phased symbol values being different from a set of symbols in the direct sequence used to spread the transmitted signal. The local spreading sequence has a nominal chip period, which is equivalent to the chip period of the over-sampled representation of the signal.Type: GrantFiled: October 7, 2004Date of Patent: April 20, 2010Assignee: SAAB ABInventor: Ian Oppermann
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Publication number: 20100091819Abstract: An arrangement for providing synchronization between a number of overlapping area access points within a wireless LAN utilizes a Power over Ethernet (PoE) cable connection to transmit synchronization signals from a centralized hub/switch to each of the access points connected to the cable. The synchronization signal takes the form of a direct sequence spread spectrum (DS-SS) signal that is coupled onto the twisted pair used to provide the low voltage PoE signal to various powered devices. At each access point, a filter is used to remove the synchronization signal from the PoE transport, allowing for the group of access points to share a common beacon signal and allow for frequency re-use among the access points. The DS-SS signal is preferable created by a combination of a baseband signal and a set of separate pseudo noise (PN) sequences defining a precision phase (“pilot tone”) signal, a time mark (superframe/beacon) signal, and a time-of-day (real-time clock) signal.Type: ApplicationFiled: December 14, 2009Publication date: April 15, 2010Inventors: Saeed S. Ghassemzadeh, Robert Raymond Miller, II, John F. Murray
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Patent number: 7697590Abstract: A chaos spreading code c(n) is inputted to a spreading unit 32. Data D1 and c(n) are multiplied in the spreading unit 32. A chaos spreading code d(n) is inputted to a spreading unit 42. Data D2 and d(n) are multiplied in the spreading unit 42. The chaos spreading codes c(n) and d(n) orthogonally cross each other. Outputs of the spreading units 32 and 42 are added by an adder 35 and transmitted through a transmitting unit 36 to a transmission path 38. By making an initial value which is set in a chaos sequence generator having a construction of a digital circuit different, the chaos spreading codes which orthogonally cross can be formed. Since the chaos spreading codes c(n) and d(n) orthogonally cross, an orthogonal modulating unit having a construction of an analog circuit for amplitude-modulating carriers which orthogonally cross can be made unnecessary and the construction can be simplified.Type: GrantFiled: June 11, 2004Date of Patent: April 13, 2010Assignees: Japan Science and Technology Agency, National Institute of Information and Communications Technology, Incorporated Administrative AgencyInventors: Ken Umeno, Akio Hasegawa, Minghui Kao
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Patent number: 7688900Abstract: A data transmitting device for transmitting data on a channel within a CDMA system may simultaneously convey data with a plurality of other data transmitting devices on one channel. The data transmitting device includes an interleaver that receives an interleaver pattern parameter, generates a respective interleaver pattern in accordance with the received parameter, and interleaves a source data stream using the generated interleaver pattern to produce an interleaved data stream. The generated interleaver pattern has interleaver characteristics that differ from the interleaver characteristics of at least one other data transmitting device that simultaneously transmits data on the channel.Type: GrantFiled: September 30, 2002Date of Patent: March 30, 2010Assignee: Panasonic CorporationInventors: Christian Wengerter, Alexander Golitschek Edler Von Elbwart, Eiko Seidel
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Patent number: 7684378Abstract: A method and apparatus for estimating channelization codes in a wireless transmit/receive unit (WTRU) using blind code detection (BCD). A WTRU receives communication bursts and detects a midamble in the received burst. A candidate code list is generated in accordance with the detected midamble. The candidate code list includes channelization codes intended for both the intended WTRU and other WTRUs. Active channelization codes among the codes in the candidate list are identified, and the identified codes are forwarded to a multi-user detector (MUD). The present invention resolves SF ambiguity in the downlink of TSM. Since the orthogonal variable spreading factor code maintains the orthogonality between codes of different SF, SFs of other WTRUs follow the SF of the intended WTRU. Moreover, since the data for other WTRUs is not used in symbol processing after MUD, the performance of MUD for the intended WTRU is preserved with the SF ambiguity of other WTRUs.Type: GrantFiled: March 31, 2005Date of Patent: March 23, 2010Assignee: InterDigital Technology CorporationInventors: Jaeyoung Kwak, Donald M. Grieco, Jung-Lin Pan, Ariela Zeira
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Publication number: 20100067514Abstract: Systems and methods for performing a handoff of an access terminal from a macro node to a femto node are disclosed. In one embodiment, the femto node is configured to transmit a predetermined signal for determining signal quality and an identifier that uniquely identifies the femto node to the access terminal. The access terminal is configured to transmit the identifier to the macro node. The femto node is identified as a hand in target based on the transmitted identifier and the macro node is configured to hand in the access terminal to the femto node.Type: ApplicationFiled: September 14, 2009Publication date: March 18, 2010Applicant: QUALCOMM IncorporatedInventors: Tao Luo, Juan Montojo, Xiaoxia Zhang
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Publication number: 20100066506Abstract: A system provides for remote monitoring using asynchronous code division multiple access (CDMA) communication techniques between a base station and one or more transponders. Each transponder is attached or otherwise associated with an object or an environment to be monitored. Upon receipt of an interrogation signal, a transponder generates and transmits a coded transponder signal containing the monitored data. The coded transponder signal is generated using a spreading code. Each transponder is associated with a unique, mutually exclusive set of spreading codes. Each spreading code is based on a unique transponder address and the monitored data to be sent. A detector asynchronously monitors received signals for any of the available spreading codes. Once the detector detects a particular spreading code, the base station can identify the source transponder and extract the monitored data.Type: ApplicationFiled: November 20, 2009Publication date: March 18, 2010Applicant: Mayo Foundation for Medical Education and ResearchInventors: Timothy Michael Schaefer, Jonathan Darrel Coker, Rick Allen Philpott, Edward Brian Welch, David R. Holmes, III
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Patent number: 7680174Abstract: A forward link power control mechanism measures the reverse link power control bits which are transmitted on the forward traffic channel. At the remote station, the reverse link power control bits from multiples base stations or multiple signal paths are measured, combined, and filtered to yield an improved measurement of the forward link signal quality. The reverse link power control bits which are deemed unreliable are omitted from use in the power control loop. The remote station generates a set of forward link power control bit in accordance with the measurements and transmits these bits to all base stations in communication with the remote station. Each base station adjusts its gain of the forward traffic channel in accordance to its measurement of the forward link power control bit.Type: GrantFiled: June 25, 2004Date of Patent: March 16, 2010Assignee: QUALCOMM IncorporatedInventors: Edward G. Tiedemann, Jr., Keith W. Saints
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Publication number: 20100060424Abstract: One or more readers transmit radio frequency (RF) beacons to be electronically reflected by tags. Data transmitted via modulated backscatter from radio frequency identification (RFID) tags is encoded so as to permit reliable demodulation of simultaneous transmissions from multiple tags. This includes the use of spreading sequences as in direct sequence spread spectrum, where the spreading sequences may be a function of the tag ID, or may be randomly chosen. Backscattered signals from multiple tags may be detected using well-known receiver techniques for code division multiple access (CDMA) systems. Readers may be equipped with transmit and/or receive antenna arrays. A receive antenna array permits a reader to estimate directions of arrival for received signals, as well as to enhance range by performing receive beamforming.Type: ApplicationFiled: March 18, 2009Publication date: March 11, 2010Applicant: Checkpoint Systems, Inc.Inventors: Ben J. Wild, Upamanyu Madhow, Kannan Ramchandran, Artem Tkachenko
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Publication number: 20100054211Abstract: Systems and methodologies that enable implementing a complete period of frequency domain pseudo random/pseudo noise (PN) sequences, wherein the PN sequences satisfy predetermined requirements or relations. Such requirements or relations include: (1) supplying substantially low time domain Peak-to-Average Ratio (PAR); (2) supplying perfect periodic autocorrelation (zero out-of-phase correlation); (3) supplying substantially perfect cross correlation for any pair of sequences; and (4) supplying sequence correlation in the frequency domain by performing additive operations only or addition and subtraction-only. Taken together, such features in a family of sequences facilitate efficient signal transmission (e.g., substantially low power usage).Type: ApplicationFiled: July 10, 2009Publication date: March 4, 2010Applicant: QUALCOMM INCORPORATEDInventor: Peter Gaal
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Patent number: 7672357Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: GrantFiled: July 11, 2006Date of Patent: March 2, 2010Assignee: NTT DoCoMo, Inc.Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20100046587Abstract: The present invention discloses a method for de-spreading quadrature pseudorandom noise, which including: inputting data sequences I? and Q?, and inputting pseudorandom noise sequences PNI and PNQ, on which quadrature pseudorandom noise de-spreading operation will be performed; in each timeslot, extracting continuously 2048 codeword from each pseudorandom noise sequence PNI and each pseudorandom noise sequence PNQ respectively, performing time-division de-multiplexing operation on the 2048 codeword respectively, and obtaining pseudorandom noise sequences PNI? and PNQ? both with a length of 1600 codeword; performing quadrature pseudorandom noise de-spreading operation on the pseudorandom noise sequences PNI? and PNQ? and the data sequences I? and Q? with a length of 1600 codeword input in the timeslot, and then outputting data sequences I and Q. The invention operates the input sequences to be performed with quadrature PN de-spreading.Type: ApplicationFiled: December 6, 2006Publication date: February 25, 2010Applicant: ZTE CORPORATIONInventors: Jiao Wu, Yu Xin, Guoping Xu
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Patent number: 7668225Abstract: At transmission, the data to be transmitted is divided into N data blocks, these N blocks are processed in parallel in N M-ary orthogonal keying (MOK) modulation channels, each modulation using a group of spread codes, each channel emitting a signal. All of these signals are transmitted in series. At reception, the signal received is processed in N M-ary orthogonal keying (MOK) demodulation channels, and the blocks obtained are grouped together in series.Type: GrantFiled: August 31, 2006Date of Patent: February 23, 2010Assignee: Commissariat a l'Energie AtomiqueInventors: Jean-René Lequepeys, Dominique Noguet, Laurent Ouvry, Didier Varreau
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Patent number: 7668276Abstract: Apparatus and methods are disclosed for adjusting phase of data signals to compensate for phase-offset variations between devices during normal operation. The phase of data signals are adjusted individually in each transmit data unit and receive data unit across multiple data slices with a common set of phase vector clock signals and a corresponding clock cycle count signal. The transmission of signal information between a first device (such as a memory controller) and a second device (such as a memory component) occurs without errors even when the accumulated delays between the first device and second device change by a half symbol time interval or more during operation of the system. The apparatus reduces the circuitry required, such as phase-lock-loops, for individually adjusting the phase of each transmit data unit and receive data unit across multiple data slices, which in turn results in reduction in complexity and cost of the system.Type: GrantFiled: October 22, 2002Date of Patent: February 23, 2010Assignee: Rambus Inc.Inventors: Craig E. Hampel, Richard E. Perego, Stefanos S. Sidiropoulos, Ely K. Tsern, Fredrick A. Ware
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Patent number: 7664162Abstract: Automatic establishment of a connection between a human interface device and a host transceiver unit. A marriage ID is exchanged in a synchronization step. The marriage ID being used by both the host transceiver and the human interface device to calculate a spread spectrum modulation pattern. In one embodiment the spread spectrum modulation is a frequency hopping spread spectrum modulation.Type: GrantFiled: July 2, 2007Date of Patent: February 16, 2010Assignee: Logitech Europe S.A.Inventors: Mark Thomas Lavelle, Hugues Michel Favey, David Ernest Wegmuller, Eric Schmid, Patrick Paul Loughnane