Patent application number | Description | Published |
20090257443 | OFDM COMMUNICATION SYSTEM AND METHOD HAVING A REDUCED PEAK-TO-AVERAGE POWER RATIO - An OFDM system embeds sequence information in the transmitted signal that reduces peak average power ratio (PAP) with minimal impact on the overall system efficiency. A marker is embedded onto the transmitted information that is used to identify the combining (inversion) sequence at the receiver. In one embodiment, selected tones in a cluster are rotated when the corresponding phase factor rotates the cluster. | 10-15-2009 |
20100040089 | METHOD AND SYSTEM FOR REDUCTION OF PEAK-TO-AVERAGE POWER RATIO OF TRANSMISSION SIGNALS COMPRISING OVERLAPPING WAVEFORMS - The present invention provides a method and system for reducing the peak to average power ratio (PAP) of a signal with low computational complexity. According to one embodiment, the present invention is applied to reduce the PAP of an OFDM signal. According to an alternative embodiment, the present invention, is applied to reduce the PAP of a CDMA signal. Rather than seeking the optimum solution, which involves significant computational complexity, the present invention provides for a number of sub-optimal techniques for reducing the PAP of an OFDM signal but with much lower computational complexity. In particular, according to one embodiment utilizing the PTS approach, an iterative technique is used to assign phase factors to each of a set of partial transmit sequences from a set of possible phase factors. Experimental results using the iterative technique showed only a slight degradation (1 dB) from the optimal approach using the same number of subblocks and subcarriers. In an alternative embodiment, which avoids feedback required by the iterative approach, a sequence of phase factors are generated randomly and assigned to each of a set of partial transmit sequences. This procedure is repeated for a pre-determined number of trials and the random sequence generating the lowest PAP is selected. In a third embodiment, a set of phase factors is generated using a structured sequence such as a Walsh sequence. | 02-18-2010 |
20110149770 | Adaptive MAC fragmentation and rate selection for 802.11 wireless networks - A method for setting and adjusting MAC fragmentation threshold for IEEE 802.11 networks operating at different data rates is presented. The fragmentation threshold is adjusted based on throughput performance, delay constraints and hidden node influence. | 06-23-2011 |
20110292985 | OFDM COMMUNICATION SYSTEM AND METHOD HAVING A REDUCED PEAK-TO-AVERAGE POWER RATIO - An OFDM system embeds sequence information in the transmitted signal that reduces peak average power ratio (PAP) with minimal impact on the overall system efficiency. A marker is embedded onto the transmitted information that is used to identify the combining (inversion) sequence at the receiver. In one embodiment, selected tones in a cluster are rotated when the corresponding phase factor rotates the cluster. | 12-01-2011 |
20130094602 | METHOD AND SYSTEM FOR REDUCTION OF PEAK-TO-AVERAGE POWER RATIO OF TRANSMISSION SIGNALS COMPRISING OVERLAPPING WAVEFORMS - The present invention provides a method and system for reducing the peak to average power ratio (PAP) of a signal with low computational complexity. According to one embodiment, the present invention is applied to reduce the PAP of an OFDM signal. According to an alternative embodiment, the present invention, is applied to reduce the PAP of a CDMA signal. Rather than seeking the optimum solution, which involves significant computational complexity, the present invention provides for a number of sub-optimal techniques for reducing the PAP of an OFDM signal but with much lower computational complexity. | 04-18-2013 |
20130094614 | OFDM COMMUNICATION SYSTEM AND METHOD HAVING A REDUCED PEAK-TO-AVERAGE POWER RATIO - An OFDM system embeds sequence information in the transmitted signal that reduces peak average power ratio (PAP) with minimal impact on the overall system efficiency. A marker is embedded onto the transmitted information that is used to identify the combining (inversion) sequence at the receiver. In one embodiment, selected tones in a cluster are rotated when the corresponding phase factor rotates the cluster. | 04-18-2013 |
20140192924 | METHOD AND SYSTEM FOR REDUCTION OF PEAK-TO-AVERAGE POWER RATIO OF TRANSMISSION SIGNALS COMPRISING OVERLAPPING WAVEFORMS - The present invention provides a method and system for reducing the peak to average power ratio (PAP) of a signal with low computational complexity. According to one embodiment, the present invention is applied to reduce the PAP of an OFDM signal. According to an alternative embodiment, the present invention, is applied to reduce the PAP of a CDMA signal. Rather than seeking the optimum solution, which involves significant computational complexity, the present invention provides for a number of sub-optimal techniques for reducing the PAP of an OFDM signal but with much lower computational complexity. | 07-10-2014 |
20140314187 | OFDM COMMUNICATION SYSTEM AND METHOD HAVING A REDUCED PEAK-TO-AVERAGE POWER RATIO - An OFDM system embeds sequence information in the transmitted signal that reduces peak average power ratio (PAP) with minimal impact on the overall system efficiency. A marker is embedded onto the transmitted information that is used to identify the combining (inversion) sequence at the receiver. In one embodiment, selected tones in a cluster are rotated when the corresponding phase factor rotates the cluster. | 10-23-2014 |