A user enters a location with a user device. A beacon device broadcasts a first beacon device code comprising a hardware identifier via a local wireless network at the location. A service application of the user device receives the first beacon device hardware identifier, logs a check-in status of the user, and transmits the check-in status to a service provider system. The beacon device generates, after a predetermined period of time, a subsequent beacon device code comprising a random number to broadcast at the location via the local wireless network. In response to receiving the subsequent beacon device code broadcast by the beacon device, the user device logs and transmits a subsequent check in status to the service provider system via the network. The service provider system provides services to the user device or another device at the location in accordance with the check-in status of the user device.

A method includes obtaining signal information corresponding to a plurality of radio signals received at two or more sensing devices from a candidate location, determining a plurality of reconstructed signals based on the signal information, determining time-estimates and frequency-estimates based on a correlation between the plurality of radio signals and the plurality of reconstructed signals, determining metadata corresponding to the plurality of radio signals based on the signal information, the time-estimates, or the frequency-estimates, transmitting at least a portion of the metadata to an information combining node, obtaining the portion of the metadata from the information combining node, determining a relationship between the metadata, and determining the candidate location based on the metadata and the relationship between the metadata. Transmission of the plurality of radio signals to the information combining node is restricted based on a bandwidth of the two or more sensing devices or the information combining node.

A method includes obtaining signal information corresponding to a plurality of radio signals received at two or more sensing devices from a candidate location, determining a plurality of reconstructed signals based on the signal information, determining time-estimates and frequency-estimates based on a correlation between the plurality of radio signals and the plurality of reconstructed signals, determining metadata corresponding to the plurality of radio signals based on the signal information, the time-estimates, or the frequency-estimates, transmitting at least a portion of the metadata to an information combining node, obtaining the portion of the metadata from the information combining node, determining a relationship between the metadata, and determining the candidate location based on the metadata and the relationship between the metadata. Transmission of the plurality of radio signals to the information combining node is restricted based on a bandwidth of the two or more sensing devices or the information combining node.

A computing device with a Dynamic Antenna Configuration Manager (DACM) for sharing of spare antennas with dedicated (wireless mode-specific) primary antennas in the computing device, which supports multiple wireless modes of operation and includes at least one shared spare antenna operable as a broadband Radio Frequency (RF) antenna over all of the device-supported wireless modes. The DACM dynamically allocates spare antennas based on active wireless connections, device usage modes, device orientation/configuration, and other user visible metrics so as to optimize user experience. Such dynamic-sharing allows device support for multiple wireless protocols (or modes of operation), but with less than the total of individual protocol-specific maximum antennas. As a result, a dynamic (variable) number of Multiple-Input Multiple-Output (MIMO) streams per wireless mode of operation may be supported within the space constraints imposed by device real estate, thereby providing the end user with a better wireless experience than with other design choices.

According to one embodiment, a wireless receiver includes reception circuitry and processor circuitry. The reception circuitry receives a radio wave from a radio wave emitter. The processor circuitry estimates a parameter of a ratio of a first received power of a line-of-sight component in the radio wave to a second received power of the radio wave, estimate the first received power based on the parameter and a value of the second received power; and calculate a distance to the radio wave emitter, based on the first received power.

A method for determining a phase bias in the signal transmitted by at least one of the radiating elements of an active antenna on the ground emitting signals into space using a space-division multiple access SDMA method, implementing a step, for each reference receiver, of comparing, to a threshold, the difference between the value of a measurement of the power received by each reference receiver and the sum, out of the radiating elements of the subset beamforming in the direction of the reference receiver, of the differences between the equivalent isotropically radiated power in the direction of the reference receiver and the free-space path loss of each radiating element of the subset.

An EM emitter includes at least three orthogonal coils driven by an oscillating voltage source, with the coils being electrically in parallel or series. When used in a vehicle, particularly an airplane, and the vehicle is lost, e.g., sinks, the emitter's EM signal passes through water with little attenuation and can be detected and the vehicle located.

A computing device with a Dynamic Antenna Configuration Manager (DACM) for sharing of spare antennas with dedicated (wireless mode-specific) primary antennas in the computing device, which supports multiple wireless modes of operation and includes at least one shared spare antenna operable as a broadband Radio Frequency (RF) antenna over all of the device-supported wireless modes. The DACM dynamically allocates spare antennas based on active wireless connections, device usage modes, device orientation/configuration, and other user visible metrics so as to optimize user experience. Such dynamic-sharing allows device support for multiple wireless protocols (or modes of operation), but with less than the total of individual protocol-specific maximum antennas. As a result, a dynamic (variable) number of Multiple-Input Multiple-Output (MIMO) streams per wireless mode of operation may be supported within the space constraints imposed by device real estate, thereby providing the end user with a better wireless experience than with other design choices.

One example includes a passive radar receiver system including an RF receiver front-end to receive a wireless source signal and a reflected signal. An antenna switch of the front-end switches a first antenna to a receiver chain during a first time to generate first radar signal data based on a combined wireless signal comprising wireless source signal and the reflected signal, and switches a second antenna to the receiver chain during a second time to generate second radar signal data based on the combined wireless signal. A signal processor generates source signal data associated with the wireless source signal based on the first and second radar signal data and generates reflected signal data associated with the reflected signal based on the first and second radar signal data, and generates target radar data associated with a target based on the source and reflected radar signal data.

Data is automatically collected; the data relevant to user attributes. That data is provided as factors for passive authenticating the user for access to a device and/or a resource. In an embodiment, the data is used to establish a profile or a pattern for the user.