A global positioning system (GPS) and Doppler augmentation (GDAUG) end receiver (GDER) can include a GDAUG module. The GDAUG module can generate a GDER position using a time of flight (TOF) of a transponded GPS signal and a Doppler shift in a GDAUG satellite (GSAT) signal. The transponded GPS signal sent from a GSAT to the GDER can include a frequency shifted copy of a GPS signal from a GPS satellite to the GSAT. The GSAT signal can include a signal generated by the GSAT to the GDER.

A global positioning system (GPS) and Doppler augmentation (GDAUG) end receiver (GDER) can include a GDAUG module. The GDAUG module can generate a GDER position using a time of flight (TOF) of a transponded GPS signal and a Doppler shift in a GDAUG satellite (GSAT) signal. The transponded GPS signal sent from a GSAT to the GDER can include a frequency shifted copy of a GPS signal from a GPS satellite to the GSAT. The GSAT signal can include a signal generated by the GSAT to the GDER.

Techniques are generally described for determining locations of a plurality of communication devices in a network. In some examples, methods for creating a location discovery infrastructure (LDI) for estimating locations of one or more of a plurality of communication nodes may comprise one or more of determining a plurality of locations in the terrain to place a corresponding plurality of beacon nodes, determining a plurality of beacon node groups for the placed beacon nodes, and determining a schedule for the placed beacon nodes to be active. Additional variants and embodiments are also disclosed.

Techniques are generally described for determining locations of a plurality of communication devices in a network. In some examples, methods for creating a location discovery infrastructure (LDI) for estimating locations of one or more of a plurality of communication nodes may comprise one or more of determining a plurality of locations in the terrain to place a corresponding plurality of beacon nodes, determining a plurality of beacon node groups for the placed beacon nodes, and determining a schedule for the placed beacon nodes to be active. Additional variants and embodiments are also disclosed.

A communications system, including at least one tag and a plurality of beacons. The tags are configured to detect beacon advertisement messages, initiate a connection with at least one of the plurality of and transmit a Constant Tone (CT) to the at least one of the plurality of beacons. The tag is further configured to determine a location thereof based on the sampled CT from both the beacon and the tag and then report the location via the one of the beacons and/or an access point. Phase ranging mitigation techniques which include hop duplication, hop interpolation and ADC DC offset correction are employed so as to provide more accurate ranging values even in the case where there are many other devices in local proximity and which are competing for use of the same RF channels as those used by the tags and beacons.

Techniques are described herein for imaging static or semi-static objects in a wireless power delivery environment and tracking non-static objects contained therein. More specifically, embodiments of the present disclosure describe techniques for determining the relative locations and movement of non-static objects in a wireless power delivery environment. Additionally, the techniques describe methods and system for generation of motion-based maps such as heat (or dwell maps) and flow maps.

A method, apparatus and computer readable storage medium are provided for reconfiguring a radio positioning support system. In a method, one or more observation reports are received. Each observation report is associated with a respective radio positioning support device of a radio positioning support system. Each observation report contains an indication for a number of radio positioning support devices and/or for each radio positioning support device from which a radio positioning support signal is observable at a position of said respective radio positioning support device. The method also determines, based on said observation reports, whether a predetermined radio positioning support criterion is met by said radio positioning support system. If it is determined that the predetermined radio positioning support criterion is not met by the radio positioning support system, the method at least partially reconfigures and/or causes at least partially reconfiguration of the radio positioning support system.

A radio-frequency method for range finding includes modulating a reference signal having an intermediate frequency to a downlink signal having a carrier frequency using a clock signal. The downlink signal is transmitted to a tag using a transceiver. An uplink signal backscattered from the tag is received and demodulated using the clock signal. The uplink signal has a frequency that is a harmonic of the carrier frequency. A distance between the tag and the transceiver is calculated based on a phase of the demodulated uplink signal. A system for range finding includes a transceiver and a processor. The transceiver modulates a reference signal to a downlink signal and transmits the downlink signal. The transceiver receives and demodulates an uplink signal. The processor is configured to receive the demodulated uplink signal and calculate a distance between the tag and the transceiver using a phase of the demodulated uplink signal.

Apparatus and methods are presented for synchronising a slave device signal to a reference timebase, in situations where the slave device lacks knowledge of the propagation delay for signals from the reference device, e.g. if the positions of one or both of the devices are unknown or classified, or the inter-device signal propagation distance is otherwise a-priori unknown. Reference signal propagation delay is determined using an exchange of signals between the devices, with each device using a differencing procedure for eliminating effects of receiver line bias and other hardware delays. In another aspect an exchange of signals between the devices is used to detect a time residual arising from an inaccurate propagation delay estimate. The synchronisation methods can be applied to a plurality of slave devices for providing a synchronised location network. In certain embodiments signals are transmitted wirelessly, while in other embodiments they are transmitted via a fixed line.

In a method for determining a location of an electronic device, a plurality of beacon signals are received from a plurality of beacon devices at the electronic device, wherein each beacon signal of the plurality of beacon signals includes an identity of a beacon device transmitting a respective beacon signal, and each beacon device of the plurality of beacon devices has a known location. A received signal strength for each beacon signal of the plurality of beacon signals is measured. A distance of the electronic device from each beacon device for which the plurality of beacon signals is received is determined, wherein the distance of the electronic device from a beacon device is based at least in part on the received signal strength of the beacon signal transmitted by the beacon device. A location of the electronic device is determined based at least on part on the distance of the electronic device from each beacon device for which the plurality of beacon signals is received.