| Patent application number | Description | Published |
|---|
| 20090110112 | Method and Apparatus for Reducing Phase Noise in Orthogonal Frequency Division Multiplexing Systems - Method and apparatus for reducing phase noise from a multi-carrier modulation (MCM) system, such as an orthogonal frequency division multiplexing (OFDM) system, by transmitting known data on a sub-carrier at a power level adapted to allow for accurate estimation. Preferably, the sub-carrier is the DC sub-carrier. | 04-30-2009 |
| 20090116473 | Channel Estimation for Synchronized Cells in a Cellular Communication System - Channel estimation is performed by user equipment operating in a mobile communications system. Estimation involves receiving a signal and analyzing it to detect a signal component from a neighboring cell. Depending on outcome, one or both of the following are determined: whether a power level of the signal component from the neighboring cell exceeds a power threshold level; and whether a difference between timing parameters of the neighboring cell's signal component and that from a serving cell is less than a timing threshold level. If the power level of the neighboring cell's signal component exceeds the power threshold level and the difference between the timing parameters of the signal components from the neighboring cell and that of the serving cell is less than the timing threshold level, then a joint channel estimation process is performed. Otherwise, a single channel estimation process is performed. | 05-07-2009 |
| 20090116568 | Method and Apparatus for Interference Rejection Combining and Detection - A multi-branch OFDM receiver combines diversity signals received over different receiver branches using interference rejection combining. The receiver generates first channel estimates associated with a serving base station, second channel estimates associated with at least one non-serving base station, and a time offset between the serving base station and non-serving base station. The receiver computes a noise covariance matrix based on the second channel estimates and the time offset, and then combines the diversity signals received over different branches using the first channel estimates and the noise covariance matrix. | 05-07-2009 |
| 20090154577 | Determination of Pre-Coding Matrix Indicators for Spatial Multiplexing in a Mobile Communications System - A pre-coding matrix is determined in an OFDMA, multiple transmit antenna communication system having a number of sub-carriers grouped into a number, M, of resource blocks. This involves determining a frequency selectivity of a channel through which received signals have propagated. A number N of selected resource blocks is then determined as a function of the frequency selectivity the N selected resource blocks being those for which pre-coding matrices will be determined, wherein N| 06-18-2009 | |
| 20090154607 | Method and Apparatus for Blind Decoding - According to the teachings presented herein, a method and apparatus provide a reduced search space for blindly decoding a message included in a signal received at a communication receiver, where the message has an unknown format. Improving blind detection efficiency in this manner offers numerous advantages, including but not limited to lower power consumption through reduced processing overhead, and lower power consumption through expanded sleep opportunities. As a non-limiting example, the communication receiver comprises a mobile station configured for operation according to Long Term Evolution (LTE) standards, as promulgated by the 3GPP for E-UTRA systems, where the mobile station is configured to reduce a search space of DCI message decoding by determining message format likelihoods and blindly decoding a received DCI message based on the message format likelihoods. | 06-18-2009 |
| 20090257517 | WIRELESS COMMUNICATION METHODS AND RECEIVERS FOR RECEIVING AND PROCESSING MULTIPLE COMPONENT CARRIER SIGNALS - A wireless communication system receiver receives and processes a signal comprising at least two component carriers carrying data scheduled to the receiver and having center frequencies spaced apart by at least one component carrier frequency difference. Each component carrier comprises a number of subcarriers spaced apart by a system subcarrier frequency spacing. A common divisor is obtained for the at least one component carrier frequency difference and the system subcarrier frequency spacing. A symbol is received on the subcarriers of the component carriers and downconverted to baseband to produce a baseband symbol. A block of padding values is inserted in the baseband symbol to produce a padded symbol. The length of the block of padding values is such that intermediate subcarriers are inserted to yield a subcarrier frequency spacing for the padded symbol equal to the common divisor. Finally the padded symbol is Fast Fourier Transform, FFT, processed. | 10-15-2009 |
| 20090257533 | SYSTEM AND METHOD OF RECEIVING AND PROCESSING MULTICOMMUNICATION SIGNALS - A receiver receives and front-end processes a plurality of component carrier signals, each carrier spaced apart in frequency. The digitized, baseband component carrier signals are inspected to determine estimates of timing offsets between the carriers. A control unit selects a first component carrier signal having data scheduled to the receiver. If data is scheduled to the receiver on other component carrier signals, the control unit generates timing and frequency offset adjustment control signals to time- and frequency-align each other component carrier signal having relevant data, to the first component carrier signal. All the relevant component carrier signals are then combined, and a single OFDM symbol, spanning all the relevant component carriers, is presented to an FFT for symbol detection. | 10-15-2009 |
| 20090258628 | Time-Error and Frequency-Error Correction in a Multi-Carrier Wireless Communications System - Methods and apparatus for automatic frequency control in wireless receivers configured to simultaneously receive multiple carrier signals at distinct radio frequencies are disclosed. An exemplary wireless device comprises at least first and second radio front-end circuits configured to receive first and second wireless communication signals transmitted via first and second radio-frequency carriers at distinct first and second radio frequencies, respectively, a control processor configured to designate a master carrier signal and a slave carrier signal from among the received wireless communication signals, and a frequency error estimation circuit configured to estimate a first receiver frequency error using the received master carrier signal. The control processor is further configured to calculate a second receiver frequency error from the first receiver frequency error, for use in compensating one or more receiver processes performed on the slave carrier signal. | 10-15-2009 |
| 20100067627 | Maximum A Posteriori Interference Estimation in a Wireless Communication System - Methods and apparatus are disclosed for estimating inter-cell interference levels for resource elements of a received Orthogonal Frequency-Division Multiplexing (OFDM) signal. In an exemplary method in a wireless receiver, a reference symbol interference levels is measured for each of a plurality of reference symbols in a received OFDM signal, and interference scaling factors are mapped to each of a plurality of resource elements of the received OFDM signal. Each interference scaling factor reflects the probability that the corresponding resource element or group of resource elements is subject to interference from an interfering OFDM signal. Interference levels for each of the resource elements are then estimated as a function of the measured reference symbol interference levels and the interference scaling factors. | 03-18-2010 |
| 20100128827 | MMSE Demodulation in a Multi-User MIMO System - A method and apparatus is provided for demodulating a desired data stream in a MU-MIMO communication system where only the precoder for the desired data stream is known a priori. The receiving terminal according to various embodiments of the present invention estimates the precoder for one or more interfering data streams. The receiving terminal can then use the known precoder for the desired data stream and the estimated precoders for the interfering data streams to perform MMSE demodulation. | 05-27-2010 |
| 20100135423 | Determining a Frequency Error in a Receiver of a Wireless Communications System - A frequency error of received signals in an OFDM receiver of a wireless communications system is determined. Symbols of a given duration are transmitted as cells on sub-carrier frequencies; and some of the cells are pilot cells modulated with reference information. The method comprises the steps of selecting at least three pilot cells (p | 06-03-2010 |
| 20100272219 | Method and Device for Automatic Gain Control - A method and apparatus for adjusting the gain of an amplifier ( | 10-28-2010 |
| 20110026415 | Interference-Aware Resource Assignment in Communication Systems - Methods and apparatus in a frequency division duplex, orthogonal frequency division multiplex communication system assign resources, including the number, frequency position, and coding, in a subframe of a downlink to a user equipment (UE) based on parameters that influence the robustness against UE self-induced interference when the UE is scheduled for uplink transmission in that subframe. | 02-03-2011 |
