A train-position detection device includes: a radio-wave's angle-of-arrival calculator configured to calculate an angle of arrival of a radio wave on the basis of a reception signal received by an array antenna and a receiver; a position acquisition unit configured to acquire information on an installation position of a ground-based wireless communication apparatus from the reception signal; a train-position calculator configured to calculate a train position on the basis of a movement distance of a train; a correction-amount-to-train-position calculator configured to calculate a train-position correction amount, by using the calculated angle of arrival, the installation position of the ground-based wireless communication apparatus acquired by the position acquisition unit, and the calculated train position; and a train-position correcting unit configured to correct the calculated train position by using the train-position correction amount calculated by the correction-amount-to-train-position calculator.

A train-position detection device includes: a radio-wave's angle-of-arrival calculator configured to calculate an angle of arrival of a radio wave on the basis of a reception signal received by an array antenna and a receiver; a position acquisition unit configured to acquire information on an installation position of a ground-based wireless communication apparatus from the reception signal; a train-position calculator configured to calculate a train position on the basis of a movement distance of a train; a correction-amount-to-train-position calculator configured to calculate a train-position correction amount, by using the calculated angle of arrival, the installation position of the ground-based wireless communication apparatus acquired by the position acquisition unit, and the calculated train position; and a train-position correcting unit configured to correct the calculated train position by using the train-position correction amount calculated by the correction-amount-to-train-position calculator.

Methods and systems for determining the direction to at least one source contributing to a wave field. A wave field partial wave expansion (PWE) model is comprised of wave field partial wave functions (PWFs) and unknown PWE coefficients corresponding to the wave field PWFs. A source PWE model is comprised of source PWFs and source PWE coefficients corresponding to the source PWFs, the source PWE coefficients being expressed in terms of source PWFs of the directional coordinates of the source. A processor, using: the output signals from at least one sensor outputting signals consistent with Nyquist criteria representative of the wave field; a library of PWFs to determine at least one of the unknown PWE coefficients; and the source PWE model, determines directional coordinates of the source (wherein the number of floating point operations are reduced) and outputs the directional coordinates to a reporter configured for reporting information to humans.

Methods and systems for determining the direction to at least one source contributing to a wave field. A wave field partial wave expansion (PWE) model is comprised of wave field partial wave functions (PWFs) and unknown PWE coefficients corresponding to the wave field PWFs. A source PWE model is comprised of source PWFs and source PWE coefficients corresponding to the source PWFs, the source PWE coefficients being expressed in terms of source PWFs of the directional coordinates of the source. A processor, using: the output signals from at least one sensor outputting signals consistent with Nyquist criteria representative of the wave field; a library of PWFs to determine at least one of the unknown PWE coefficients; and the source PWE model, determines directional coordinates of the source (wherein the number of floating point operations are reduced) and outputs the directional coordinates to a reporter configured for reporting information to humans.

Mechanisms compressive sampling to detect direction of arrival (DoA) of a signal of interest (SoI), comprising: in each of a plurality of receiver paths, receiving the SoI and producing a received signal using an antenna; and using a modulator to: receive a modulator input signal (MIS) based on the received signal produced by the antenna in the path; modulate the MIS at multiple points in time (MPIT) based on different ones of a plurality of pseudo-random numbers; and produce a plurality of modulated output signals in response to the modulating of the MIS at the MPIT; summing across the receiver paths the one of the modulated output signals produced by each of the receiver paths for each of the MPIT, to produce a plurality of sum signals each corresponding to one of the MPIT; and performing a compressed sensing recovery algorithm to recover the DoA of the SoI.

In an ultra-wideband (UWB) receiver, a received UWB signal is periodically digitized as a series of ternary samples. During a carrier acquisition mode, the samples are continuously correlated with a predetermined preamble sequence to develop a correlation value. When the value exceeds a predetermined threshold, indicating that the preamble sequence is being received, estimates of the channel impulse response (CIR) are developed. When a start-of-frame delimiter (SFD) is detected, the best CIR estimate is provided to a channel matched filter (CMF). During a data recovery mode, the CMF filters channel-injected noise from the sample stream. Both carrier phase errors and data timing errors are continuously detected and corrected during both the carrier acquisition and data recovery modes of operation.

In an ultra-wideband (UWB) receiver, a received UWB signal is periodically digitized as a series of ternary samples. During a carrier acquisition mode, the samples are continuously correlated with a predetermined preamble sequence to develop a correlation value. When the value exceeds a predetermined threshold, indicating that the preamble sequence is being received, estimates of the channel impulse response (CIR) are developed. When a start-of-frame delimiter (SFD) is detected, the best CIR estimate is provided to a channel matched filter (CMF). During a data recovery mode, the CMF filters channel-injected noise from the sample stream. Both carrier phase errors and data timing errors are continuously detected and corrected during both the carrier acquisition and data recovery modes of operation.

Embodiments include methods, systems and computer readable storage medium for determining receipt of a malicious message by a vehicle. The method includes receiving, by a processor, a message and determining, by the processor, a message type associated with the message. The method includes calculating, by the processor, an angle of arrival (AoA) for the message, wherein the AoA is an angle of receipt for the message. The method includes comparing, by the processor, the AoA to a message angle, wherein the message angle is an expected angle of receipt or angle range for the message based on the message type. The method includes flagging, by the processor, the message as being malicious in response to the comparison indicating that the AoA is not equivalent to or within a predetermined tolerance of the message angle. The method includes suppressing, by the processor, a notification or warning associated with the flagged message.

A method of combined direction finding (DF) and fine timing measurement (FTM) positioning in a wireless location area network (WLAN) is proposed. A multiple antenna IEEE 802.11 transmitting device (AP) can transmit signal preamble containing multiple Long Training Field (LTF) symbols in a radio frame from multiple antennas, which allows a receiving device (STA) to resolve multiple DF sounding signals transmitted from the multiple antennas and thereby estimating angle of departure (AoD). On the other hand, the AP can estimate angle of arrival (AoA) from radio signals transmitted from the STA. When the radial resolution error of AoD or AoA positioning increases, DF positioning and fine-timing measurement (FTM) ranging can be jointly applied to reduce the radial resolution error and extends the AoD/AoA service area with positing accuracy.

A method of combined direction finding (DF) and fine timing measurement (FTM) positioning in a wireless location area network (WLAN) is proposed. A multiple antenna IEEE 802.11 transmitting device (AP) can transmit signal preamble containing multiple Long Training Field (LTF) symbols in a radio frame from multiple antennas, which allows a receiving device (STA) to resolve multiple DF sounding signals transmitted from the multiple antennas and thereby estimating angle of departure (AoD). On the other hand, the AP can estimate angle of arrival (AoA) from radio signals transmitted from the STA. When the radial resolution error of AoD or AoA positioning increases, DF positioning and fine-timing measurement (FTM) ranging can be jointly applied to reduce the radial resolution error and extends the AoD/AoA service area with positing accuracy.