Abstract: A wireless receiver (e.g., access point (AP)) is a member of a group of a plurality of receivers in a wireless local area network and time synchronized with other receivers in the group. A channel scan list is generated from a plurality of wireless channels available in one or more frequency bands. A channel is selected for the receiver to monitor from the channel scan list based on a current time at the receiver such that each of the plurality of receivers in the group are scanning the same channel at the same time. The selected channel is scanned and signal characteristic information (e.g., received signal strength (RSS)) is generated for the signals received during a given scan duration.

Abstract: Techniques are presented for detecting rogue wireless beacon devices. Wireless transmissions from beacon devices are received at a plurality of receiver devices. The wireless transmissions of the beacon devices comprise packets that carry information used for location-based services for mobile wireless devices. Content of one or more fields of the packets transmitted by the beacon devices and received by one or more of the receiver devices is obtained. The content of one or more fields of the packets is analyzed to detect an unauthorized beacon device. The analyzing operation may involve comparing the content of the one or more fields of the packets against a list that contains one or more identifiers for authorized beacon devices. In another form, analyzing may involve analyzing the content of the one or more fields of the packets with pattern information related to advertising content or advertising source.

Abstract: A wireless receiver (e.g., access point (AP)) is a member of a group of a plurality of receivers in a wireless local area network and time synchronized with other receivers in the group. A channel scan list is generated from a plurality of wireless channels available in one or more frequency bands. A channel is selected for the receiver to monitor from the channel scan list based on a current time at the receiver such that each of the plurality of receivers in the group are scanning the same channel at the same time. The selected channel is scanned and signal characteristic information (e.g., received signal strength (RSS)) is generated for the signals received during a given scan duration.

Abstract: Techniques are presented herein for distinguishing between the DC component of a real signal and DC energy of a received signal due to the radio receiver circuitry. Samples are obtained of a received signal derived from output of a receiver of a communication device. A mean of the samples is computed over a sample window comprising a predetermined number of samples. First and second thresholds are provided, the first threshold being greater than the second threshold. An absolute value of the mean is compared with respect to the first threshold and the second threshold as samples are obtained in the sample window. A selection is made between the first threshold and the second threshold for purposes of comparison with the absolute value of the mean to determine whether energy at DC is a true/real DC component of the received signal or is due to circuitry of the receiver.

Abstract: Wider bandwidth transmissions are dynamically enabled in a wireless networking environment. During a transmit opportunity time interval for a wireless network device, a transmission is sent in a primary channel in a frequency band in which the primary channel and a secondary channel may be used simultaneously to send a wider bandwidth transmission. Activity is monitored in the secondary channel. A determination is made as to whether the secondary channel is free based on the monitoring. When it is determined that the secondary channel is free, the wider bandwidth transmission is sent in the primary and secondary channels.

Abstract: A channel sounding scheme is presented herein that relies on a combination of a first channel sounding procedure and a second channel sounding procedure. The first channel sounding technique is one that involves an exchange of dedicated channel sounding related signals to determine channel conditions between the first wireless communication device and the particular second wireless communication device. The second channel sounding technique is one in which channel conditions are implicitly discovered from any signals transmitted by the particular second wireless communication device to the first wireless communication device. A first wireless communication device computes updates to steering matrix information used for beamforming one or more signal streams to a particular second wireless communication device based on a combination of the first channel sounding technique and the second channel sounding technique.

Abstract: Techniques are presented herein for distinguishing between the DC component of a real signal and DC energy of a received signal due to the radio receiver circuitry. Samples are obtained of a received signal derived from output of a receiver of a communication device. A mean of the samples is computed over a sample window comprising a predetermined number of samples. First and second thresholds are provided, the first threshold being greater than the second threshold. An absolute value of the mean is compared with respect to the first threshold and the second threshold as samples are obtained in the sample window. A selection is made between the first threshold and the second threshold for purposes of comparison with the absolute value of the mean to determine whether energy at DC is a true/real DC component of the received signal or is due to circuitry of the receiver.

Abstract: A set of receiver path circuits is allocated for processing a radio-frequency (RF) signal provided by receive antennas coupled to the receiver path circuits. The RF signal may belong to a first signal class, such as Wi-Fi. A first gain control signal is applied to each of the allocated receiver path circuits to condition a signal level of the RF signal for the first signal class. A second gain control signal is applied to another set of receiver path circuits coupled to the receive antennas to condition the RF signal of a second signal class. First receive gain control signals are generated from the RF signals of the first signal class by the allocated set of the receiver path circuits. The first receive gain control signals are configured to optimize the signal level for processing the first signal class. A second receive gain control signal is generated to optimize the signal level of the RF signal for the second signal class.

Abstract: A first device explicitly sounds a wireless channel with respect to a second device even when the second device cannot sound all the antenna/transmit paths of the first device. The first device has a first plurality of antennas and corresponding transmitters and the second device has a second plurality antennas and corresponding receivers. The first device wirelessly transmits a plurality of sounding frames to the second device such that at least one of the first plurality of antennas is kept constant across the plurality of sounding frames. The first device receives from the second device at least one feedback message containing channel matrix information derived from reception of the sounding frames at the second plurality of antennas of the second device. The first device derives a full wireless channel estimate between the first plurality of antennas of the first device and the second plurality of antennas of the second device.

Abstract: In one embodiment, an apparatus includes a plurality of antennas, a receiver in communication with said plurality of antennas for receiving one or more packets in a block based modulation environment, a switch interposed between a portion of the antennas and the receiver for switching between the antennas, and a processor for calculating angle of arrival for use in identifying a location of a mobile device transmitting the one or more packets.

Abstract: Techniques are presented for distributed processing Distributed-Input Distributed-Output (DIDO) wireless communication. A plurality of base stations (e.g., APs) are provided, each configured to wirelessly serve one or more wireless devices (e.g., clients). At least first and second base stations are configured to transmit simultaneously at an agreed upon time. The first and second base stations are each configured to locally generate steering matrix information used to spatially precode their respective data transmissions in order to steer their respective data transmissions to their one or more wireless devices while nulling to the one or more client devices of the other base station. Moreover, the first and second base stations are each configured to locally generate a transmit waveform by applying the steering matrix information to their respective data transmissions.

Abstract: Techniques are provided to improve the performance of wireless devices that serve wireless client devices in a wireless network in the presence of narrowband interference. The wireless device that serves wireless client devices in the wireless network receives energy in a plurality of channels of a frequency band. The received energy is analyzed for occurrence and type of interference in each channel. A quality metric is generated for each channel incorporating the occurrence and type of interference detected in the channel. For each channel, a bias value against selection of the channel is assigned based on whether narrowband interference is present in the channel. The bias value for each channel is applied to the quality metric for the channel to produce an adjusted quality metric for each channel. A channel is selected based on the adjusted quality metric for each of the plurality of channels.

Abstract: Techniques are provided for receiving a transmitted first packet that was formatted using a known scrambling algorithm with an unknown scrambling seed. An encoded packet payload is extracted from the first packet header. The encoded packet payload header is decoded to obtain a first scrambled packet payload header. For each potential value of the unknown seed, the first scrambled packet payload header is descrambled to produce a first set of descrambled packet payload headers and for each potential value of initial register values associated with a cyclic redundancy check, the cyclic redundancy check is executed comprising polynomial division on each of the descrambled packet payload headers such that when the polynomial division results in a zero remainder, a potential unscrambled payload header for the first packet is obtained. Information about the first packet is obtained from the potential unscrambled payload header.

Abstract: A channel sounding scheme is presented herein that relies on a combination of a first channel sounding procedure and a second channel sounding procedure. The first channel sounding technique is one that involves an exchange of dedicated channel sounding related signals to determine channel conditions between the first wireless communication device and the particular second wireless communication device. The second channel sounding technique is one in which channel conditions are implicitly discovered from any signals transmitted by the particular second wireless communication device to the first wireless communication device. A first wireless communication device computes updates to steering matrix information used for beamforming one or more signal streams to a particular second wireless communication device based on a combination of the first channel sounding technique and the second channel sounding technique.

Abstract: Wider bandwidth transmissions are dynamically enabled in a wireless networking environment. During a transmit opportunity time interval for a wireless network device, a transmission is sent in a primary channel in a frequency band in which the primary channel and a secondary channel may be used simultaneously to send a wider bandwidth transmission. Activity is monitored in the secondary channel. A determination is made as to whether the secondary channel is free based on the monitoring. When it is determined that the secondary channel is free, the wider bandwidth transmission is sent in the primary and secondary channels.

Abstract: Techniques are provided to adaptively adjust a clear channel assessment threshold for use when a wireless device is to transmit in a wireless network that operates on a channel in a radio frequency band. A first wireless device, configured to wirelessly communicate with one or more second wireless device in the wireless network, receives energy on the channel in the frequency band, analyzes the received energy to detect interference on the channel and determines a type of interference detected in the received energy. The clear channel assessment threshold is adjusted by an amount depending on the type of interference detected.

Abstract: Techniques are provided to improve the performance of wireless devices that serve wireless client devices in a wireless network in the presence of narrowband interference. The wireless device that serves wireless client devices in the wireless network receives energy in a plurality of channels of a frequency band. The received energy is analyzed for occurrence and type of interference in each channel. A quality metric is generated for each channel incorporating the occurrence and type of interference detected in the channel. For each channel, a bias value against selection of the channel is assigned based on whether narrowband interference is present in the channel. The bias value for each channel is applied to the quality metric for the channel to produce an adjusted quality metric for each channel. A channel is selected based on the adjusted quality metric for each of the plurality of channels.

Abstract: At a plurality of first devices, wireless transmissions are received at different locations in a region where multiple target devices may be emitting. Identifier data associated with reception of emissions from target devices at multiple first devices is generated. Similar identifier data associated with received emissions at multiple first devices are grouped together into a cluster record that potentially represents the same target device detected by multiple first devices. Data is stored that represents a plurality of cluster records from identifier data associated with received emissions made over time by multiple first devices. The cluster records are analyzed over time to correlate detections of target devices across multiple first devices.

Abstract: Techniques are provided to adaptively adjust a clear channel assessment threshold for use when a wireless device is to transmit in a wireless network that operates on a channel in a radio frequency band. A first wireless device, configured to wirelessly communicate with one or more second wireless device in the wireless network, receives energy on the channel in the frequency band, analyzes the received energy to detect interference on the channel and determines a type of interference detected in the received energy. The clear channel assessment threshold is adjusted by an amount depending on the type of interference detected.

Abstract: Techniques are provided for receiving a transmitted first packet that was formatted using a known scrambling algorithm with an unknown scrambling seed. An encoded packet payload is extracted from the first packet header. The encoded packet payload header is decoded to obtain a first scrambled packet payload header. For each potential value of the unknown seed, the first scrambled packet payload header is descrambled to produce a first set of descrambled packet payload headers and for each potential value of initial register values associated with a cyclic redundancy check, the cyclic redundancy check is executed comprising polynomial division on each of the descrambled packet payload headers such that when the polynomial division results in a zero remainder, a potential unscrambled payload header for the first packet is obtained. Information about the first packet is obtained from the potential unscrambled payload header.