End-to-end Transmission System Patents (Class 375/141)
  • Publication number: 20100208770
    Abstract: 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: Application
    Filed: September 19, 2007
    Publication date: August 19, 2010
    Inventor: Karl Torbjörn Wigren
  • Publication number: 20100208771
    Abstract: 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: Application
    Filed: March 17, 2010
    Publication date: August 19, 2010
    Inventors: Brecken H. Uhl, Arthur D. Hurtado, Daniel A. Law
  • Patent number: 7778377
    Abstract: 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: Grant
    Filed: May 31, 2005
    Date of Patent: August 17, 2010
    Assignee: Agere Systems Inc.
    Inventors: Vladimir Sindalovsky, Lane A. Smith, Craig B. Ziemer
  • Patent number: 7769079
    Abstract: 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: Grant
    Filed: October 5, 2006
    Date of Patent: August 3, 2010
    Inventor: Yu-Cheun Jou
  • Publication number: 20100189162
    Abstract: 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: Application
    Filed: September 5, 2007
    Publication date: July 29, 2010
    Inventors: Takashi Yoshimoto, Ryota Yamada, Toshizo Nogami
  • Publication number: 20100177804
    Abstract: 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: Application
    Filed: May 30, 2008
    Publication date: July 15, 2010
    Inventors: Jin Sam Kwak, Seung Hee Han, Min Seok Noh, Yeong Hyeon Kwon, Hyun Woo Lee, Dong Cheol Kim
  • Patent number: 7756219
    Abstract: 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: Grant
    Filed: July 14, 2005
    Date of Patent: July 13, 2010
    Assignee: GLOBALFOUNDRIES Inc.
    Inventors: Sascha Beyer, Wolfram Kluge, Michael Schmidt
  • Patent number: 7756193
    Abstract: 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: Grant
    Filed: September 21, 2006
    Date of Patent: July 13, 2010
    Assignee: Broadcom Corporation
    Inventors: Louis Jacobus Botha, Frederic Christian Marc Hayem, Hendrik Johannes Conroy
  • Patent number: 7756000
    Abstract: 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: Grant
    Filed: May 17, 2007
    Date of Patent: July 13, 2010
    Assignee: Harris Corporation
    Inventors: David B. Chester, David H. Damerow
  • Publication number: 20100164941
    Abstract: 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: Application
    Filed: December 11, 2009
    Publication date: July 1, 2010
    Inventor: Jong-Seok Chae
  • Publication number: 20100166043
    Abstract: 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: Application
    Filed: January 17, 2007
    Publication date: July 1, 2010
    Inventors: Hideichi Sasaoka, Hisato Iwai, Yusuke Miyamoto
  • Publication number: 20100165828
    Abstract: 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: Application
    Filed: December 29, 2008
    Publication date: July 1, 2010
    Applicant: Harris Corporation
    Inventors: Alan J. Michaels, David B. Chester
  • Publication number: 20100166041
    Abstract: 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: Application
    Filed: December 29, 2008
    Publication date: July 1, 2010
    Applicant: Harris Corporation
    Inventors: Alan J. Michaels, David B. Chester
  • Patent number: 7746919
    Abstract: 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: Grant
    Filed: November 8, 2006
    Date of Patent: June 29, 2010
    Assignee: AT&T Intellectual Property I, L.P.
    Inventor: Arunabha Ghosh
  • Patent number: 7742775
    Abstract: 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: Grant
    Filed: June 12, 2009
    Date of Patent: June 22, 2010
    Assignee: On-Ramp Wireless, Inc.
    Inventor: Theodore J. Myers
  • Publication number: 20100150210
    Abstract: 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: Application
    Filed: September 29, 2006
    Publication date: June 17, 2010
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Zheng Zhao, Jifeng Li
  • Patent number: 7738531
    Abstract: 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: Grant
    Filed: May 5, 2008
    Date of Patent: June 15, 2010
    Assignee: QUALCOMM Incorporated
    Inventor: Christopher Patrick
  • Patent number: 7738540
    Abstract: 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: Grant
    Filed: September 26, 2005
    Date of Patent: June 15, 2010
    Assignee: Panasonic Corporation
    Inventors: Hidetoshi Yamasaki, Hitoshi Takai, Hideki Nakahara, Kenji Miyanaga
  • Publication number: 20100142589
    Abstract: 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: Application
    Filed: September 28, 2006
    Publication date: June 10, 2010
    Applicant: KDDI CORPORATION
    Inventors: Toshinori Suzuki, Noriaki Miyazaki
  • Publication number: 20100142590
    Abstract: 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: Application
    Filed: December 8, 2006
    Publication date: June 10, 2010
    Inventors: Thomas Höhne, Gang Xu
  • Publication number: 20100142591
    Abstract: 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: Application
    Filed: October 26, 2009
    Publication date: June 10, 2010
    Applicant: INFINEON TECHNOLOGIES AG
    Inventor: Ayman F. NAGUIB
  • Patent number: 7733946
    Abstract: 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: Grant
    Filed: April 29, 2005
    Date of Patent: June 8, 2010
    Assignee: Alcatel Lucent
    Inventors: Michel-Guy Francon, Paul Vincent, Nicolas Chuberre
  • Patent number: 7733939
    Abstract: 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: Grant
    Filed: November 3, 2005
    Date of Patent: June 8, 2010
    Assignee: Broadcom Corporation
    Inventor: Jason Alexander Trachewsky
  • Patent number: 7729408
    Abstract: 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: Grant
    Filed: February 9, 2004
    Date of Patent: June 1, 2010
    Assignee: Cypress Semiconductor Corporation
    Inventors: Robert Mack, Stephen O'Connor
  • Publication number: 20100127831
    Abstract: 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: Application
    Filed: September 17, 2009
    Publication date: May 27, 2010
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Jong-sub CHA, Seung-il MYONG, Heyung-sub LEE, Sang-hyun MO, Jong-suk CHAE
  • Patent number: 7724802
    Abstract: 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: Grant
    Filed: September 23, 2004
    Date of Patent: May 25, 2010
    Assignee: Fujitsu Ten Limited
    Inventors: Kanako Honda, Osamu Isaji
  • Publication number: 20100124206
    Abstract: 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: Application
    Filed: October 2, 2009
    Publication date: May 20, 2010
    Inventors: Gregory E. Bottomley, Dirk Gerstenberger, Lars Lindbom, Yi-Pin Eric Wang
  • Patent number: 7720133
    Abstract: 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: Grant
    Filed: August 25, 2005
    Date of Patent: May 18, 2010
    Assignee: Sony Corporation
    Inventors: Akihiro Koyama, Akira Hayashi, Shinsuke Tashiro, Tsuyoshi Hashimoto, Masayuki Takada, Katsumi Watanabe
  • Patent number: 7720130
    Abstract: 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: Grant
    Filed: August 28, 2002
    Date of Patent: May 18, 2010
    Assignee: Texas Instruments Incorporated
    Inventors: Yan Hui, Gibong Jeong
  • Publication number: 20100118920
    Abstract: 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: Application
    Filed: August 6, 2009
    Publication date: May 13, 2010
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Pan-soo KIM, Dae-ig CHANG, Ho-jin LEE, A. VANELLI-CORALLI, G.E. CORAZZA, C. PALESTINI, R. PEDONE, M. VILLANTI
  • Patent number: 7711030
    Abstract: 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: Grant
    Filed: October 21, 2005
    Date of Patent: May 4, 2010
    Assignee: Rearden, LLC
    Inventor: Stephen G. Perlman
  • Publication number: 20100103983
    Abstract: 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: Application
    Filed: October 29, 2008
    Publication date: April 29, 2010
    Inventors: Yi-Pin Wang, Gregory E. Bottomley
  • Publication number: 20100103984
    Abstract: 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: Application
    Filed: November 11, 2009
    Publication date: April 29, 2010
    Applicant: FUJITSU LIMITED
    Inventor: Toshio Kawasaki
  • Patent number: 7706428
    Abstract: 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: Grant
    Filed: February 10, 2006
    Date of Patent: April 27, 2010
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Leif Wilhelmsson, Michael Faulkner
  • Publication number: 20100098135
    Abstract: 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: Application
    Filed: October 15, 2009
    Publication date: April 22, 2010
    Applicant: QUALCOMM Incorporated
    Inventor: Alecsander P. Eitan
  • Patent number: 7701998
    Abstract: 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: Grant
    Filed: October 7, 2004
    Date of Patent: April 20, 2010
    Assignee: SAAB AB
    Inventor: Ian Oppermann
  • Publication number: 20100091819
    Abstract: 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: Application
    Filed: December 14, 2009
    Publication date: April 15, 2010
    Inventors: Saeed S. Ghassemzadeh, Robert Raymond Miller, II, John F. Murray
  • Patent number: 7697590
    Abstract: 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: Grant
    Filed: June 11, 2004
    Date of Patent: April 13, 2010
    Assignees: Japan Science and Technology Agency, National Institute of Information and Communications Technology, Incorporated Administrative Agency
    Inventors: Ken Umeno, Akio Hasegawa, Minghui Kao
  • Patent number: 7688900
    Abstract: 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: Grant
    Filed: September 30, 2002
    Date of Patent: March 30, 2010
    Assignee: Panasonic Corporation
    Inventors: Christian Wengerter, Alexander Golitschek Edler Von Elbwart, Eiko Seidel
  • Patent number: 7684378
    Abstract: 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: Grant
    Filed: March 31, 2005
    Date of Patent: March 23, 2010
    Assignee: InterDigital Technology Corporation
    Inventors: Jaeyoung Kwak, Donald M. Grieco, Jung-Lin Pan, Ariela Zeira
  • Publication number: 20100067514
    Abstract: 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: Application
    Filed: September 14, 2009
    Publication date: March 18, 2010
    Applicant: QUALCOMM Incorporated
    Inventors: Tao Luo, Juan Montojo, Xiaoxia Zhang
  • Publication number: 20100066506
    Abstract: 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: Application
    Filed: November 20, 2009
    Publication date: March 18, 2010
    Applicant: Mayo Foundation for Medical Education and Research
    Inventors: Timothy Michael Schaefer, Jonathan Darrel Coker, Rick Allen Philpott, Edward Brian Welch, David R. Holmes, III
  • Patent number: 7680174
    Abstract: 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: Grant
    Filed: June 25, 2004
    Date of Patent: March 16, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Edward G. Tiedemann, Jr., Keith W. Saints
  • Publication number: 20100060424
    Abstract: 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: Application
    Filed: March 18, 2009
    Publication date: March 11, 2010
    Applicant: Checkpoint Systems, Inc.
    Inventors: Ben J. Wild, Upamanyu Madhow, Kannan Ramchandran, Artem Tkachenko
  • Publication number: 20100054211
    Abstract: 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: Application
    Filed: July 10, 2009
    Publication date: March 4, 2010
    Applicant: QUALCOMM INCORPORATED
    Inventor: Peter Gaal
  • Patent number: 7672357
    Abstract: 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: Grant
    Filed: July 11, 2006
    Date of Patent: March 2, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
  • Publication number: 20100046587
    Abstract: 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: Application
    Filed: December 6, 2006
    Publication date: February 25, 2010
    Applicant: ZTE CORPORATION
    Inventors: Jiao Wu, Yu Xin, Guoping Xu
  • Patent number: 7668225
    Abstract: 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: Grant
    Filed: August 31, 2006
    Date of Patent: February 23, 2010
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Jean-René Lequepeys, Dominique Noguet, Laurent Ouvry, Didier Varreau
  • Patent number: 7668276
    Abstract: 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: Grant
    Filed: October 22, 2002
    Date of Patent: February 23, 2010
    Assignee: Rambus Inc.
    Inventors: Craig E. Hampel, Richard E. Perego, Stefanos S. Sidiropoulos, Ely K. Tsern, Fredrick A. Ware
  • Patent number: 7664162
    Abstract: 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: Grant
    Filed: July 2, 2007
    Date of Patent: February 16, 2010
    Assignee: Logitech Europe S.A.
    Inventors: Mark Thomas Lavelle, Hugues Michel Favey, David Ernest Wegmuller, Eric Schmid, Patrick Paul Loughnane