Patent application number | Description | Published |
20120120839 | Methods for monitoring channel sounding quality in WLAN devices - A method of monitoring channel-sounding quality for VHT WiFi devices is provided. A mobile station (the receiver) receives a sounding signal transmitted from an access point (the transmitter) over one or multiple sub-channels of a wide channel in a wireless network. The receiver performs channel estimation and determines an estimated channel response matrix. The receiver then calculates sounding quality for each valid sub-channel by computing an estimation error of the received sounding signal based on the estimated channel matrix. The receiver transmits a feedback message to the transmitter. The feedback message contains sounding quality information derived from the calculated channel sounding quality. If the channel sounding qualities for all valid sub-channels are poor, then a null VHT channel feedback frame is sent back to the transmitter. | 05-17-2012 |
20120263055 | Fast Link Adaptation and Transmit Power Control in Wireless Networks - An open-loop fast link adaptation scheme is proposed in an OFDM system. An access point first transmits a downlink packet comprising an open-loop link metric to a wireless station. The open-loop link metric contains a transmit power of the downlink packet plus a receiver sensitivity of the access point. The wireless station measures a received signal strength indication (RSSI) value of the downlink packet. The wireless station then applies open-loop link adaptation and determines a modulation and coding scheme (MCS) based on the open-loop link metric and the RSSI value. The open-loop link adaptation scheme is especially suitable for smart meter/sensor networks as it reduces overhead and increases link capacity. | 10-18-2012 |
20130010632 | Simultaneous Feedback Signaling for Dynamic Bandwidth Selection - A method of simultaneously providing channel quality feedback information in all valid sub-channels is provided to facilitate and improve the performance of dynamic transmission bandwidth adjustment and fast link adaptation. A receiving device receives a sounding signal over a wide channel in a wireless system. The sounding signal is transmitted from a transmitting device over multiple sub-channels of the wide channel. The receiving device estimates channel quality information based on the sounding signal for each sub-channel. The channel quality information includes estimated average SNR and recommended MCS and other channel quality metrics. The receiving device transmits a feedback message to the transmitting device. The feedback message contains the estimated channel quality information for all valid sub-channels within the transmission bandwidth. The transmitting device performs dynamic transmission bandwidth selection and fast link adaptation based on the channel quality information for all valid sub-channels. | 01-10-2013 |
20130107916 | Methods for Inter-User Interference Indication Feedback and Usage in MU-MIMO Wireless Systems | 05-02-2013 |
20130195029 | Method and System for Supporting Incompatible Channelization of a Wireless Communications System - A method of supporting incompatible channelization in a wireless communications system is provided. A coordinating device determines a first set of physical parameters of a first wireless channel. The first set of physical parameters includes a channel bandwidth, a central frequency, a transmit power limit, and a modulation and coding scheme. The coordinating device establishes communication with a first set of communications devices over the first wireless channel. The coordinating device then broadcasts a channel-adjustment message and determines a protection period. The channel-adjustment message comprises a set of instructions on how to adjust to a second set of physical parameters of a second wireless channel. A second set of communications devices adjust physical parameters based on the channel-adjustment message. Finally, the coordinating device communicates with the second set of communications devices over the second wireless channel during the protection period. | 08-01-2013 |
20130315325 | Method and Apparatus of Beam Training for MIMO Operation - The disclosed invention provides an efficient method for beam training to enable spatial multiplexing MIMO operation and spatial combining in a wireless network. The invention discloses a simple and efficient beam-training algorithm and protocol for MIMO operation that operates in high SNR condition for reliable MIMO operation. In one novel aspect, the best MIMO beam combinations are determined after TX sector sweeping and RX sector sweeping. In addition, the selection criteria includes not only signal quality, but also considers mutual interference and leakage among multiple MIMO spatial streams to improve overall MIMO performance. | 11-28-2013 |
20130343211 | Beam-Change Indication for Channel Estimation Improvement in Wireless Networks - A method of channel estimation enhancement is provided. In a wireless communications system, a transmitting device transmits a long preamble frame comprising a first training field, a signal field, and a second training field. The signal field has a beam-change indicator bit indicates whether there is beam change between the first training field and the second training field. A receiving device receives the long preamble frame, performs a first channel estimation based on the first training field, and performs a second channel estimation based on the second training field. If the beam-change indicator bit indicates negative beam change, then the receiving device performs channel estimation enhancement by combining the first channel estimation and the second channel estimation. As a result, channel estimation performance is improved. | 12-26-2013 |
20140071892 | APPARATUS AND METHOD OF DATA COMMUNICATIONS IN MILLIMETER WAVE NETWORK - The method and apparatus of data communications for a transmitter in a millimeter wave network are provided. The method includes: generating a control physical layer (CPHY) preamble; generating a header, wherein the header includes a mode indicator; modulating and encoding a payload according to the mode indicator; generating a packet according to the control physical layer (CPHY) preamble, the header and the payload; and transmitting the packet. | 03-13-2014 |