Patent application number | Description | Published |
20100009634 | INTER-CELL INTERFERENCE CANCELLATION FRAMEWORK - Communication techniques enable efficient communication to an UE (User Equipment) that is subject to a dominant interference signal that is transmitted by a different base station. Disclosed interference cancellation techniques, both UE-centric and network-centric, are suitable to this situation. These techniques are particularly advantageous when undesirable or difficult to introduce changes in the physical (PHY) and medium access control (MAC) layers at the existing base stations. UE-centric framework refers to an approach largely implemented by UEs to include pico or femto cells. Network-centric framework closed-loop coordination between base stations and UEs mitigate interference thereby improving network performance. In particular, an interfering base-station can help a “victim” UE by adjusting downlink pilot and control power and to adjust traffic data rates responsive to information that the “victim” UEs provide, including information about the interfering link and performance of the cancellation itself sent over the air or using the backhaul. | 01-14-2010 |
20100009705 | INTER-CELL INTERFERENCE CANCELLATION FRAMEWORK - Communication techniques enable efficient communication to UE (User Equipment) that is subject to a dominant interference signal that is transmitted by a different base station. Disclosed interference cancellation techniques, both UE-centric and network-centric, are suitable to this situation. These techniques are particularly advantageous when it is undesirable or difficult to introduce changes in the physical (PHY) and medium access control (MAC) layers at the existing base stations. An UE-centric framework refers to an approach largely implemented by UEs to include pico or femto cells. Network-centric framework closed-loop coordination between base stations and UEs achieves interference mitigation thereby improving network performance. In particular, an interfering base-station can help a “victim” UE by adjusting downlink pilot and control power and to adjust traffic data rates responsive to information that the “victim” UEs provide, including information about the interfering link and performance of the cancellation itself sent over the air or using backhaul. | 01-14-2010 |
20100011269 | SYSTEMS AND METHODS FOR UPLINK INTER-CELL INTERFERENCE CANCELLATION USING HYBRID AUTOMATIC REPEAT REQUEST (HARQ) RETRANSMISSIONS - Systems, methods, apparatus, devices and computer program products enhance uplink inter-cell interference cancellation with HARQ retransmissions. The decoding of a data packet depends on whether the interfering packet was decoded. Since the interfering packet is itself transmitted using a HARQ process, the transmission by the victim UT can be accomplished to take this situation into account. The latency of the victim UT can be varied based on the need for energy efficient transmission. In accordance with one specific aspect, if the receiver can decode multiple packets simultaneously, high data rates can be achieved using packet pipelining. | 01-14-2010 |
20110183607 | METHOD AND APPARATUS FOR ESTABLISHING COMMUNICATIONS IN LOW SIGNAL TO NOISE RATIO ENVIRONMENTS - An apparatus is disclosed having a receiver configured to communicate, by a first apparatus, with a second apparatus in a first mode; determine side information by the first apparatus based on the communication during the first mode; and store the side information by the first apparatus for communication in a second mode with the second apparatus, wherein the first and second modes of communication have different date rates. A method for wireless communications is also disclosed. | 07-28-2011 |
Patent application number | Description | Published |
20080205333 | UPLINK SCHEDULING FOR FAIRNESS IN CHANNEL ESTIMATION PERFORMANCE - Systems and methodologies are described that facilitate mitigation of interference through uplink scheduling in a wireless communication environment. Access points can assign multiple terminals to a single tile or segment of shared resource (e.g., a time frequency region) to maximize the number of terminals supported. However, combinations of certain types of terminals can cause a significant increase in interference. In particular, allocating multiple terminals having a relatively high velocity (e.g., terminals located in moving vehicles) to a single tile can cause an unacceptable increase in interference. To mitigate interference, high velocity terminals can be identified. Once identified, terminals can be allocated to the available tiles based at least in part upon avoiding combinations that result in a significant increase in interference. | 08-28-2008 |
20080232484 | METHOD AND APPARATUS FOR IMPROVED ESTIMATION OF SELECTIVE CHANNELS IN AN OFDMA SYSTEM WITH DEDICATED PILOT TONES - The present disclosure provides a method and apparatus of channel estimation for a wireless communication system. Dedicated pilot symbols transmitted over at least one time-frequency region for at least one user are received. Channel parameters are estimated for the at least one time-frequency region based on the received dedicated pilot symbols. | 09-25-2008 |
20080235311 | SIMPLIFIED EQUALIZATION FOR CORRELATED CHANNELS IN OFDMA - Systems and methodologies are described that facilitate equalization of received signals in a wireless communication environment. Multiple transmit and/or receive antennas and utilize MIMO technology to enhance performance. A single tile of transmitted data, including a set of modulation symbols, can be received at multiple receive antennas, resulting in multiple tiles of received modulation symbols. Corresponding modulation symbols from multiple received tiles can be processed as a function of channel and interference estimates to generate a single equalized modulation symbol. Typically, the equalization process is computationally expensive. However, the channels are highly correlated. This correlation is reflected in the channel estimates and can be utilized to reduce complex equalization operations. In particular, a subset of the equalizers can be generated based upon the equalizer function and the remainder can be generated using interpolation. In addition, the equalizer function itself can be simplified. | 09-25-2008 |
20090245090 | Broadband Pilot Channel Estimation Using A Reduced Order FFT and a Hardware Interpolator - Within a receiver, a channel estimation mechanism involves a hardware interpolator. In a first mode, narrowband pilot values are analyzed to generate channel parameters that are supplied to the interpolator such that the interpolator generates channel estimate values. The channel estimate values are used to demodulate a tile of a frame. In a second mode, broadband pilot values are supplied to an IFFT, thereby generating time domain values. After time domain processing, an FFT is employed to generate intermediate channel estimate values. These intermediate values are analyzed to determine channel parameters, which in turn are supplied to the hardware interpolator so that the interpolator generates a larger number of channel estimate values. After phase adjustment, the channel estimate values are used in demodulation. Use of the interpolator in the broadband mode allows the FFT employed to be of a smaller order, and to consume less power and/or processing resources. | 10-01-2009 |
20090245430 | EFFICIENT PARALLEL SUB-PACKET DECODING USING MULTIPLE DECODERS - A configurable decoder within a receiver (for example, within a wireless communication device) includes numerous decoders. In one mode, the multiple decoders are used to decode different sub-packets of a packet. When one decoder completes decoding the last sub-packet assigned to it of the packet, then that decoder generates a packet done indication. A control circuit receives the packet done indications, and when all the decoders have generated packet done indications then the control circuit initiates an action. In one example, the action is the interrupting of a processor. The processor responds by reading status information from the control circuit, thereby resetting the interrupt. End-of-packet markers are usable to generate packet done indications and to generate EOP interrupts. Similarly, end-of-group markers are usable to generate group done indications and to generate EOG interrupts. The decoder block is configurable to process sub-packets of a packet using either one or multiple decoders. | 10-01-2009 |
20100239055 | EMULATION OF N-BITS UNIFORM QUANTIZER FROM MULTIPLE INCOHERENT AND NOISY ONE-BIT MEASUREMENTS - Certain aspects of the present disclosure relate to a method for emulating N-bits uniform quantization of a received pulse signal by using one-bit signal measurements. | 09-23-2010 |
20110261862 | SYSTEM AND METHOD FOR DETECTING AND PROCESSING RECEIVED SIGNAL WITH PULSE SEQUENCE - Methods of detecting a pulse sequence in a received signal are disclosed, each of which entails operating on samples of the received signal. One method entails determining a correlation of samples with a reference sequence, and detecting the pulse sequence based on the correlation. Another method entails selecting a reference sample associated with a pulse, and detecting the pulse sequence by analyzing samples based on one or more lengths of a time hopping interval and the reference sample. Another method entails selecting a reference sample associated with non-restricted time hopping intervals, and detecting the pulse sequence by analyzing samples that are based on substantially one or more lengths of a half pulse interval and the reference sample. Further, disclosed is a method of determining a timing drift by selecting samples, determining a time delay between the selected samples, and determining the timing drift based on the determined time delay and an expected time delay. | 10-27-2011 |
20110292819 | TWO-WAY RANGING MESSAGING SCHEME - In a two-way ranging scheme where a first apparatus (e.g., device) determines a distance to a second apparatus (e.g., device), specified packets are sent between these apparatuses at specified times to facilitate the determination of the distance. In some aspects, these packets may be defined and/or sent in a manner that enables the apparatuses to detect a leading edge of a received packet with a high degree of accuracy. For example, an apparatus may transmit a packet a defined period of time after transmitting or receiving another packet. In addition, a packet may comprise a defined symbol sequence that is used by an apparatus that receives the packet to identify a leading edge of the packet. | 12-01-2011 |
20110292820 | TWO-WAY RANGING MESSAGING SCHEME - In a two-way ranging scheme where a first apparatus (e.g., device) determines a distance to a second apparatus (e.g., device), specified packets are sent between these apparatuses at specified times to facilitate the determination of the distance. In some aspects, these packets may be defined and/or sent in a manner that enables the apparatuses to detect a leading edge of a received packet with a high degree of accuracy. For example, an apparatus may transmit a packet a defined period of time after transmitting or receiving another packet. In addition, a packet may comprise a defined symbol sequence that is used by an apparatus that receives the packet to identify a leading edge of the packet. | 12-01-2011 |
20110292972 | SYSTEM AND METHOD FOR TRANSMTTING AND RECEIVING SIGNAL WITH QUASI-PERIODIC PULSE SEQUENCE - System and method are disclosed for synchronization of a transmitting device and a receiving device that communicate with each other via pulse modulation. The synchronization technique entails the transmitting device sending one or more quasi-periodic pulse sequences to the receiving device. A quasi-periodic pulse sequence is based on a substantially periodic pulse sequence, and may include some non-periodic pulses or not include some periodic pulses. The transmitting device may transmit frames each including a preamble that comprises one or more quasi-periodic pulse sequences, and a data payload that may comprise data. The receiving device receives the signal, generates samples of the signal, and detects the quasi-periodic pulse sequences in the received signal by analyzing samples based on a sample associated with a pulse and the period associated with the substantially periodic pulse sequence. The receiving device is further able to detect frames based on the detection of the sequence, and extract data therefrom. | 12-01-2011 |
20110294449 | SIGNAL-BASED GAIN CONTROL - In a signal-based gain control scheme, one or more gain levels used for processing signals are selected based on characteristics of previously received signals. For example, different gain levels may be used to receive sets of signals whereupon certain characteristics of the received sets of signals are determined. One or more gain levels are then selected based on these characteristics whereby another signal is processed based on the selected gain level(s). In some aspects, the signal-based gain control scheme may be employed to facilitate two-way ranging operations between two devices. For example, leading edge detection may involve determining a characteristic of a received signal, determining a threshold based on the characteristic, and identifying a leading edge associated with the received signal based on the threshold. In some aspects, the signal-based gain control scheme may be employed in an ultra-low power pulse-based communication system (e.g., in ultra-wideband communication devices). | 12-01-2011 |
20110294450 | SIGNAL CHARACTERISTIC-BASED LEADING EDGE DETECTION - In a signal-based gain control scheme, one or more gain levels used for processing signals are selected based on characteristics of previously received signals. For example, different gain levels may be used to receive sets of signals whereupon certain characteristics of the received sets of signals are determined. One or more gain levels are then selected based on these characteristics whereby another signal is processed based on the selected gain level(s). In some aspects, the signal-based gain control scheme may be employed to facilitate two-way ranging operations between two devices. For example, leading edge detection may involve determining a characteristic of a received signal, determining a threshold based on the characteristic, and identifying a leading edge associated with the received signal based on the threshold. In some aspects, the signal-based gain control scheme may be employed in an ultra-low power pulse-based communication system (e.g., in ultra-wideband communication devices). | 12-01-2011 |
20110316747 | LEADING EDGE DETECTION - A leading edge associated with a received signal is detected to provide, for example, time of arrival information for a ranging algorithm. In some aspects, a method of leading edge detection involves sampling a received signal, generating a drift compensated signal based on the samples, reconstructing the received signal based on the drift compensated signal, and identifying a leading edge associated with the received signal based on the reconstructed signal. | 12-29-2011 |
20120155425 | PILOT DESIGN FOR IMPROVED CHANNEL AND INTERFERENCE ESTIMATION - Techniques for transmitting pilot and for processing received pilot to obtain channel and interference estimates are described. A terminal may generate pilot symbols for a first cluster in a time frequency block based on a first sequence and may generate pilot symbols for a second cluster in the time frequency block based on a second sequence. The first and second sequences may include common elements arranged in different orders and may be considered as different versions of a single sequence. The terminal may transmit the pilot symbols in their respective clusters. A base station may obtain received pilot symbols from multiple clusters in the time frequency block. The base station may form each of multiple basis vectors with multiple versions of the sequence assigned to the terminal and may process the received pilot symbols with the multiple basis vectors to obtain a channel estimate for the terminal. | 06-21-2012 |
20130235946 | PILOT DESIGN FOR IMPROVED CHANNEL AND INTERFERENCE ESTIMATION - Techniques for transmitting pilot and for processing received pilot to obtain channel and interference estimates are described. A terminal may generate pilot symbols for a first cluster in a time frequency block based on a first sequence and may generate pilot symbols for a second cluster in the time frequency block based on a second sequence. The first and second sequences may include common elements arranged in different orders and may be considered as different versions of a single sequence. The terminal may transmit the pilot symbols in their respective clusters. A base station may obtain received pilot symbols from multiple clusters in the time frequency block. The base station may form each of multiple basis vectors with multiple versions of the sequence assigned to the terminal and may process the received pilot symbols with the multiple basis vectors to obtain a channel estimate for the terminal. | 09-12-2013 |
20140219395 | SYSTEM AND METHOD FOR TRANSMTTING AND RECEIVING SIGNAL WITH QUASI-PERIODIC PULSE SEQUENCE - System and method are disclosed for synchronization of a transmitting device and a receiving device that communicate with each other via pulse modulation. The synchronization technique entails the transmitting device sending one or more quasi-periodic pulse sequences to the receiving device. A quasi-periodic pulse sequence is based on a substantially periodic pulse sequence, and may include some non-periodic pulses or not include some periodic pulses. The transmitting device may transmit frames each including a preamble that comprises one or more quasi-periodic pulse sequences, and a data payload that may comprise data. The receiving device receives the signal, generates samples of the signal, and detects the quasi-periodic pulse sequences in the received signal by analyzing samples based on a sample associated with a pulse and the period associated with the substantially periodic pulse sequence. The receiving device is further able to detect frames based on the detection of the sequence, and extract data therefrom. | 08-07-2014 |