Patent application number | Description | Published |
20080309405 | Power Amplifier Pre-Distortion - The present invention is directed to systems and methods for reducing the distortion of power amplifiers. In particular, methods and systems are described that enable a determination of a pre-distortion correction signal to be determined, which when added to the nominal signal, a reduction in the distortion of the power amplifier results. In addition, methods and systems are described that enable calibration of individual power amplifiers to be accomplished for use with the above described approach. More specifically, the methods and systems are described for use in a MIMO application. These approaches may be applied to on-chip power amplifiers, off-chip power amplifiers, or any combination thereof. | 12-18-2008 |
20080310351 | Preamble Formats for MIMO Wireless Communications - A method for generating a preamble of a frame for a multiple input multiple output (MIMO) wireless communication begins by, for each transmit antenna of the MIMO wireless communication, generating a carrier detect field, wherein, from transmit antenna to transmit antenna, the carrier detect field is cyclically shifted. The method continues by, for a first grouping of the transmit antennas of the MIMO wireless communication: generating a first guard interval following the carrier detect field; and generating at least one channel sounding field, wherein, from transmit antenna to transmit antenna in the first grouping, the at least one channel sounding field is cyclically shifted, and wherein the at least one channel sounding field follows the first guard interval. The method continues by, when the MIMO wireless communication includes more than the first grouping of the transmit antennas, for another grouping of the transmit antennas: generating at least one other channel sounding field, wherein, from transmit antenna to transmit antenna in the another grouping, the at least one other channel sounding field is cyclically shifted, and wherein the at least one other channel sounding field follows the at least one channel sounding field; and generating the first guard interval prior to the at least one other channel sounding field. | 12-18-2008 |
20100266064 | MIMO WIRELESS COMMUNICATION GREENFIELD PREAMBLE FORMATS - A method for multiple input multiple output wireless communication begins by determining protocols of wireless communication devices within a proximal region. The method continues by determining whether the protocols of the wireless communication devices within the proximal region are of a like protocol. The method continues by determining the number of transmit antennas. The method continues, when the protocols of the wireless communication devices within the proximal region are of the like protocol, formatting a preamble of a frame of the wireless communication utilizing at least one of cyclic shifting of symbols, cyclic shifting of tones, sparse tone allocation, and sparse symbol allocation based on the number of transmit antennas. | 10-21-2010 |
20110044395 | MIXED MODE PREAMBLE FOR MIMO WIRELESS COMMUNICATIONS - A preamble of a frame for a multiple input multiple output (MIMO) wireless communication for a first transmit antenna of the MIMO communication includes a legacy preamble portion in accordance with a legacy wireless communication protocol. The preamble of the frame for the MIMO wireless communication for the first transmit antenna also includes a current protocol preamble portion in accordance with a protocol of the MIMO wireless communication. The preamble of a frame for at least a second antenna of the MIMO communication includes a cyclically shifted legacy preamble portion for the frame. The preamble of the frame for the MIMO wireless communication for the second transmit antenna also includes a second current protocol preamble portion in accordance with a protocol of the MIMO wireless communication. | 02-24-2011 |
20110280331 | PREAMBLE FORMATS FOR MIMO WIRELESS COMMUNICATIONS - A method for generating a preamble of a frame for a multiple input multiple output (MIMO) wireless communication begins by, for each transmit antenna, generating a carrier detect field. The method continues by, for a first grouping of the transmit antennas, generating a first guard interval following the carrier detect field; and generating at least one channel sounding field. Continuing, the method applies cyclical shift prior to transmission via the first grouping of the transmit antennas. When the MIMO wireless communication includes more than the first grouping of the transmit antennas, for another grouping of the transmit antennas. For the another grouping of the transmit antennas, generating at least one other channel sounding field. The method proceeds by generating the first guard interval prior to the at least one other channel sounding field, and applying another cyclical shift prior to transmission via the another grouping of the transmit antennas. | 11-17-2011 |
20110299611 | METHOD AND SYSTEM FOR MULTI-ANTENNA PREAMBLES FOR WIRELESS NETWORKS PRESERVING BACKWARD COMPATIBILITY - A method for processing a wireless signal includes performing by one or more processors, selecting a plurality of training sequences from a preamble of the wireless signal. Each of the selected plurality of training sequences may include a plurality of energy tones. The selected plurality of training sequences from the preamble may be shifted, in time domain, to generate a plurality of subsequent preambles for transmission. Each of the generated plurality of subsequent preambles may include the plurality of energy tones. The preamble may include a legacy preamble and/or an 802.11(n) preamble. The shifting in the time domain may include circular shifting. The circular shifting may include forward circular shifting and/or backwards circular shifting. | 12-08-2011 |
20120008610 | MIXED MODE PREAMBLE FOR MIMO WIRELESS COMMUNICATIONS - A preamble of a frame for a multiple input multiple output (MIMO) wireless communication for a first transmit antenna of the MIMO communication includes a legacy preamble portion in accordance with a legacy wireless communication protocol. The preamble of the frame for the MIMO wireless communication for the first transmit antenna also includes a current protocol preamble portion in accordance with a protocol of the MIMO wireless communication. The preamble of a frame for at least a second antenna of the MIMO communication includes a cyclically shifted legacy preamble portion for the frame. The preamble of the frame for the MIMO wireless communication for the second transmit antenna also includes a second current protocol preamble portion in accordance with a protocol of the MIMO wireless communication. | 01-12-2012 |
20120320885 | MIXED MODE PREAMBLE FOR MIMO WIRELESS COMMUNICATIONS - A preamble of a frame for a multiple input multiple output (MIMO) wireless communication for a first transmit antenna of the MIMO communication includes a legacy preamble portion in accordance with a legacy wireless communication protocol. The preamble of the frame for the MIMO wireless communication for the first transmit antenna also includes a current protocol preamble portion in accordance with a protocol of the MIMO wireless communication. The preamble of a frame for at least a second antenna of the MIMO communication includes a cyclically shifted legacy preamble portion for the frame. The preamble of the frame for the MIMO wireless communication for the second transmit antenna also includes a second current protocol preamble portion in accordance with a protocol of the MIMO wireless communication. | 12-20-2012 |
20120321015 | PREAMBLE FORMATS FOR MIMO WIRELESS COMMUNICATIONS - A method for generating a preamble of a frame for a multiple input multiple output (MIMO) wireless communication begins by, for each transmit antenna, generating a carrier detect field. The method continues by, for a first grouping of the transmit antennas, generating a first guard interval, and at least one channel sounding field. Continuing, the method applies cyclical shift prior to transmission via the first grouping of the transmit antennas. When the MIMO wireless communication includes more than the first grouping of the transmit antennas, for another grouping of the transmit antennas. For the another grouping of the transmit antennas, generating at least one other channel sounding field. The method proceeds by generating the first guard interval prior to the at least one other channel sounding field, and applying another cyclical shift prior to transmission via the another grouping of the transmit antennas. | 12-20-2012 |
20130009701 | Power Amplifier Pre-Distortion - The present invention is directed to systems and methods for reducing the distortion of power amplifiers. In particular, methods and systems are described that enable a determination of a pre-distortion correction signal to be determined, which when added to the nominal signal, a reduction in the distortion of the power amplifier results. In addition, methods and systems are described that enable calibration of individual power amplifiers to be accomplished for use with the above described approach. More specifically, the methods and systems are described for use in a MIMO application. These approaches may be applied to on-chip power amplifiers, off-chip power amplifiers, or any combination thereof. | 01-10-2013 |
20130089054 | MIMO WIRELESS COMMUNICATION GREENFIELD PREAMBLE FORMATS - A method for multiple input multiple output wireless communication begins by determining protocols of wireless communication devices within a proximal region. The method continues by determining whether the protocols of the wireless communication devices within the proximal region are of a like protocol. The method continues by determining the number of transmit antennas. The method continues, when the protocols of the wireless communication devices within the proximal region are of the like protocol, formatting a preamble of a frame of the wireless communication utilizing at least one of cyclic shifting of symbols, cyclic shifting of tones, sparse tone allocation, and sparse symbol allocation based on the number of transmit antennas. | 04-11-2013 |