Abstract: Systems, methods, and devices select antennas to enhance the range and throughput of wireless communications devices. Methods include identifying a plurality of combinations of antennas based on a plurality of available antennas for a wireless communications device, and generating, using a processing device included in a multiple-input-multiple-output (MIMO) device, a plurality of quality metrics including at least one quality metric for each of the identified combinations of antennas, where each of the at least one quality metrics represents a signal quality of a signal associated with each of the plurality of antennas, and wherein the signal is a spatial stream. Methods further include selecting at least two antennas from the plurality of combinations of antennas based, at least in part, on the plurality of quality metrics, where the at least two antennas are selected for use by the wireless communications device during a transmitting or receiving operation.

Abstract: Systems, methods, and devices select antennas to enhance the range and throughput of wireless communications devices. Methods include identifying a plurality of combinations of antennas based on a plurality of available antennas for a wireless communications device, and generating, using a processing device included in a multiple-input-multiple-output (MIMO) device, a plurality of quality metrics including at least one quality metric for each of the identified combinations of antennas, where each of the at least one quality metrics represents a signal quality of a signal associated with each of the plurality of antennas, and wherein the signal is a spatial stream. Methods further include selecting at least two antennas from the plurality of combinations of antennas based, at least in part, on the plurality of quality metrics, where the at least two antennas are selected for use by the wireless communications device during a transmitting or receiving operation.

Abstract: Disclosed are methods and systems for delaying packet transmissions over a wireless communication channel until a more favorable channel condition is detected. A device may measure a channel metric when it receives periodic beacon signals. The device may compare the channel metric against a programmed metric threshold. If the channel metric is less than the metric threshold, the device may delay the transmission of a packet until a later transmission window or transmit opportunity (TXOP) when the channel metric rises above the metric threshold, indicating the presence of a more favorable condition for transmission, or until a preconfigured timeout period elapses before the more favorable condition is found.

Abstract: Disclosed are methods and systems for delaying packet transmissions over a wireless communication channel until a more favorable channel condition is detected. A device may measure a channel metric when it receives periodic beacon signals. The device may compare the channel metric against a programmed metric threshold. If the channel metric is less than the metric threshold, the device may delay the transmission of a packet until a later transmission window or transmit opportunity (TXOP) when the channel metric rises above the metric threshold, indicating the presence of a more favorable condition for transmission, or until a preconfigured timeout period elapses before the more favorable condition is found.

Abstract: According to embodiments, methods, devices and systems can include monitoring all of a first channel for a first monitoring period. After the first monitoring period, monitoring at least one narrow band for at least a first narrow band signal. In response to detecting the first narrow band signal, establishing a network connection over the narrow band, wherein the at least one narrow band has a frequency range less than one half that of the first channel.

Abstract: Techniques for guided placement of a wireless device are described herein. In an example embodiment, a wi-fi wireless device comprises a radio frequency (RF) transceiver coupled to a baseband processor. The RF transceiver is configured to receive an RF signal transmitted over a wireless channel and to convert the RF signal to a modulated digital signal. The baseband processor is configured to receive the modulated digital signal from the RF transceiver, extract a wireless packet from the modulated digital signal, and compute an Exponential Effective SNR Mapping (EESM) value based on the preamble of the wireless packet, where the computed EESM value indicates the quality of the wireless channel at the current location of the wireless device. The baseband processor is further configured to provide a quality indicator based on the EESM value for the current location of the wireless device.

Abstract: Disclosed are methods and systems for delaying packet transmissions over a wireless communication channel until a more favorable channel condition is detected. A device may measure a channel metric when it receives periodic beacon signals. The device may compare the channel metric against a programmed metric threshold. If the channel metric is less than the metric threshold, the device may delay the transmission of a packet until a later transmission window or transmit opportunity (TXOP) when the channel metric rises above the metric threshold, indicating the presence of a more favorable condition for transmission, or until a preconfigured timeout period elapses before the more favorable condition is found.

Abstract: Devices, systems and methods generate a packet including a first preamble and a narrow band packet. Embodiments assign a first frequency band to the first preamble and assign a second frequency band to the narrow band packet. The second frequency band is a first sub-band of the first frequency band. Embodiments transmit the packet by transmitting the first preamble across the first frequency band and transmitting the narrow band packet across the second frequency band. The narrow band packet includes a second preamble and narrow band packet data.

Abstract: Embodiments can include methods, devices and systems which can transmitting a preamble across a first channel according to a first communication protocol; sequentially transmitting signal values in a plurality of narrow bands; monitoring the narrow bands for response communications; and upon detecting response communications on at least one of the narrow bands, establishing communications across at least one of the narrow bands. Each narrow band can be a different portion of the first channel.

Abstract: According to embodiments, methods, devices and systems can include monitoring all of a first channel for a first monitoring period. After the first monitoring period, monitoring at least one narrow band for at least a first narrow band signal. In response to detecting the first narrow band signal, establishing a network connection over the narrow band, wherein the at least one narrow band has a frequency range less than one half that of the first channel.

Abstract: Devices, systems and methods generate a packet including a first preamble and a narrow band packet. Embodiments assign a first frequency band to the first preamble and assign a second frequency band to the narrow band packet. The second frequency band is a first sub-band of the first frequency band. Embodiments transmit the packet by transmitting the first preamble across the first frequency band and transmitting the narrow band packet across the second frequency band. The narrow band packet includes a second preamble and narrow band packet data.

Abstract: Disclosed are methods and systems for delaying packet transmissions over a wireless communication channel until a more favorable channel condition is detected. A device may measure a channel metric when it receives periodic beacon signals. The device may compare the channel metric against a programmed metric threshold. If the channel metric is less than the metric threshold, the device may delay the transmission of a packet until a later transmission window or transmit opportunity (TXOP) when the channel metric rises above the metric threshold, indicating the presence of a more favorable condition for transmission, or until a preconfigured timeout period elapses before the more favorable condition is found.

Abstract: Systems, methods, and devices select antennas to enhance the range and throughput of wireless communications devices. Methods include identifying a plurality of combinations of antennas based on a plurality of available antennas for a wireless communications device, and generating, using a processing device included in a multiple-input-multiple-output (MIMO) device, a plurality of quality metrics including at least one quality metric for each of the identified combinations of antennas, where each of the at least one quality metrics represents a signal quality of a signal associated with each of the plurality of antennas, and wherein the signal is a spatial stream. Methods further include selecting at least two antennas from the plurality of combinations of antennas based, at least in part, on the plurality of quality metrics, where the at least two antennas are selected for use by the wireless communications device during a transmitting or receiving operation.

Abstract: Embodiments can include methods, devices and systems which can transmitting a preamble across a first channel according to a first communication protocol; sequentially transmitting signal values in a plurality of narrow bands; monitoring the narrow bands for response communications; and upon detecting response communications on at least one of the narrow bands, establishing communications across at least one of the narrow bands. Each narrow band can be a different portion of the first channel.

Abstract: According to embodiments, methods, devices and systems can include monitoring all of a first channel for a first monitoring period. After the first monitoring period, monitoring at least one narrow band for at least a first narrow band signal. In response to detecting the first narrow band signal, establishing a network connection over the narrow band, wherein the at least one narrow band has a frequency range less than one half that of the first channel.

Abstract: Techniques for guided placement of a wireless device are described herein. In an example embodiment, a wi-fi wireless device comprises a radio frequency (RF) transceiver coupled to a baseband processor. The RF transceiver is configured to receive an RF signal transmitted over a wireless channel and to convert the RF signal to a modulated digital signal. The baseband processor is configured to receive the modulated digital signal from the RF transceiver, extract a wireless packet from the modulated digital signal, and compute an Exponential Effective SNR Mapping (EESM) value based on the preamble of the wireless packet, where the computed EESM value indicates the quality of the wireless channel at the current location of the wireless device. The baseband processor is further configured to provide a quality indicator based on the EESM value for the current location of the wireless device.

Abstract: According to embodiments, methods, devices and systems can include generating packet data for a narrow band packet. Transmitting first preamble data across a first channel followed by the narrow band packet with a second preamble across at least one resource unit (RU). The RU can have a smaller bandwidth than the first channel and occupy a portion of the first channel. The first preamble can be configured to enable detection of a packet transmitted in the first channel, and the second preamble is configured to enable detection of a packet transmitted in the RU without the first preamble.

Abstract: A system includes: a radar scanner disposed to scan the interior of a container; an interrogator in communication with the scanner; and a processing system in communication with the interrogator, in which the processing system displays information about the interior of the container. A method includes: mounting a radar scanner antenna to a container so as to scan the interior of the container; connecting a coupler to the scanner so that the scanner communicates scanning data via the coupler to the exterior of the container. Another method includes: coupling an interrogator and radar processing system to a scanner mounted on a container; and processing radar scan data from the interior of the container. Another method includes: linking a radar processing system via a communications link to an interrogator that is coupled to a scanner mounted on a container; and processing radar scan data from the interior of the container.

Abstract: An orthogonal frequency division multiplexing (OFDM) communication system is adapted for radar ranging and imaging. A radar system includes an orthogonal frequency division multiplexing (OFDM) radio communications transmitter configured to transmit information bits using one or more payload symbols in a transmitted signal; and a receiver configured to: construct the payload symbols from the information bits provided by the transmitter; receive the payload symbols in the transmitted signal reflected from a target; apply a matched filter to the received payload symbols using the constructed payload symbols as a template; and process a magnitude response at an output of the matched filter for estimating location and imaging of the target.

Abstract: A system includes a multi-system approach to detecting concealed weapons and person borne improvised explosive devices (PBIED). A first and second radar system operate at different center frequencies to provide, respectively, isolation of a target of interest from clutter and fine detail information on the target, such as whether the target is a living person, whether a concealed object may be present, material composition of the object, and shape, size, and position of the target relative to the system. Circular polarized radar beam may be used to distinguish a suspect object from within a crowd of people. Radar image of the object may be overlaid on visual image of a person carrying the object. Radar tracking of the object is coordinated with visual tracking of the target provided by a camera system, with visual display and tracking of the target overlaid with the radar information.