Systems, methods, and apparatus are provided for automated identification of open space in a wireless communications spectrum, by identifying sources of signal emission in the spectrum by automatically detecting signals, analyzing signals, comparing signal data to historical and reference data, creating corresponding signal profiles, and determining information about the open space based upon the measured and analyzed data in near real-time.

Systems (100) and methods (400) for space-based geolocation. The methods involve receiving by at least two first satellites a maritime signal transmitted from a vessel on or near Earth. The first satellites are deployed in space so as to have overlapping coverage areas. The maritime signal (received at the at least two first satellites) is then used to determine a geographic location of the vessel on Earth using at least one of a Time Difference of Arrival (TDOA) and a Frequency Difference of Arrival (FDOA).

The invention relates to a flight guidance system for the flight support of a aircraft (1), said system comprising a plurality of fixed ground stations (4a to 4e) respectively comprising a transmitting and/or receiving unit (5a to 5e), and at least one transmitting and/or receiving unit (6) that is arranged on the aircraft (1), the transmitting units being act up to send position signals (7) and the receiving units being set up to receive said position signals (7). The flight guidance system comprises at least one position determination unit (9, 10) that is connected to at least some of the transmitting and/or receiving units (5a to 5e, 6, 6a to 6c) and set up to determine locations of the transmitting and/or receiving unit (6) arranged on the aircraft, according to the position signals (7) that are sent by the fixed transmitting units and received by the at least one receiving unit arranged on the aircraft and/or sent by the at least one transmitting nail arranged on the aircraft and received by the fixed receiving units. The flight guidance system is designed for flight support of the aircraft according to the determined locations.

Systems (100) and methods (400) for providing Digital Selective Calling (DSC) based services. The methods involve: using Space-Born Maritime (SBM) receivers of satellites (104) deployed in space as a satellite constellation to collect and process DSC emergency messages transmitted from DSC transmitters of terrestrial radios; using the satellites to position validate the DSC emergency messages; determining first positions of the DSC transmitters in transit based on geolocation data and time location data respectively assigned by the satellites to the DSC emergency messages; and validating the first positions to more precise second positions based on results of cross-correlations of the geolocation data and time location data with Automatic Identification Systems (AIS) data obtained for the DSC transmitters.

A method for location determination in a wireless communications system solves a minimization problem using estimated time-of-arrivals (TOAs) of reference signals [108, 110, 112] received by a receiving node [100] from transmitting nodes [102, 104, 106] and predetermined locations of the transmitting nodes, to produce an estimate of unknown receiving node location and/or an estimate of an unknown time of transmission (t) of the reference signals. The minimization problem is defined in terms of a theoretical system model of time-of-arrivals (TOAs), linearized globally as a function of the unknown receiving node location, the unknown time of transmission (t) of the reference signals, and an additional intermediate variable (u) that defines a non-linear quadratic constraint over position coordinates of the unknown receiving node location and the time of transmission (t) of the reference signals, wherein the minimization problem optimizes the additional intermediate variable (u). The method may also be implemented with the roles of transmitters and receivers interchanged.

Various aspects of the present disclosure relate to a UE that receives, from a location server of a non-terrestrial network, first control signaling indicating a first PRS configuration that includes positioning assistance data and measurement reporting configuration. The UE also receives second control signaling indicating a second PRS configuration that indicates adapted PRS information based at least in part on mobility, an interference level, and/or a propagation delay pattern. The UE also receives third control signaling indicating a third PRS configuration that includes a duration for reporting a measurement of reference signals based at least in part on the adapted PRS information. The UE transmits, to the location server of the NTN, a report indicating the measurement of the reference signals and/or a location estimate based at least in part on the duration for the reporting.

Embodiments provided describe detections of RF leakage test signal emanating from cable plant. In one embodiment a single mobile receive antenna, connected to a complex demodulator mobile receiver, receives a stabilized test signal radiating from the cable plant. The test signal may be a known continuous wave (CW) carrier or other deterministic signal. The received test signal varies in phase as a function of a position of the mobile receive antenna relative to the location of a leakage antenna. The phase variance forms a Doppler shift as the test antenna moves relative to the leakage antenna. The receiver generates multiple in-phase (I) and quadrature (Q) test signal samples over a SPA (synthetic phased array) distance as the test antenna's travels, and the samples are inserted into a Fourier transform. The result of the transform is instantaneous Doppler frequency shift, from which a bearing angle can be computed.

A method for improving geolocation accuracy in a passive radar warning receiver, using synchronized data curve-fit and interpolation to asynchronous and noisy receiver and navigation measurements over observation periods that are extended to reduce inaccuracies caused by noise. The present disclosure yields synchronized data samples at intervals short enough that constant-rate equations are valid, even though the actual motions over the observation interval may be more complex and have higher-order dynamics. It reduces noise, synchronizes data samples, and is readily adapted to motions with variable acceleration. The method generates rate samples short enough to satisfy constant rate assumptions, yet fit data over intervals long enough to enhances measurement accuracy by reducing measurement noise.

A system and method for transient satellite doppler signal position determination by receiving multiple measured signals, determining transmission characteristics for those signals, determining orbital characteristics of satellites associated with those signals via a Doppler calculation, identifying the satellites from the transmission and orbital characteristics, determining a closest approach point responsive to identifying the satellites and the Doppler calculations, determining current positions of the satellites relative to the receiver from the closest approach point determinations via comparison to an orbital location-defining modeling equation associated with the first satellite, and determining a geolocation of the receiver responsive to each of the current position of the satellites relative to the receiver.

The invention relates to a method and a system for position determination of at least one object, in particular inside a building. In a method for position determination of at least one object, at least four transmitters transmit circularly polarized signals and a receiver to be localized receives the circularly polarized signals. At least two and in particular all transmitters transmit periodic signals of different frequencies, these frequencies being closely adjacent.