5 results about "Time of arrival" patented technology

The position of a mobile unit (12) within a detection zone is determined. An acoustic signal is emitted from the mobile unit and received along a first path (54). An echo of the signal is received after reflection from a surface (46) within said detection zone. The position of the mobile unit (12) within the detection zone is determined from the times of arrival of the signal and echo.

A vehicle on-board unit is configured and arranged to report an estimated time of arrival and an accuracy indicator for an estimated time of arrival from historical estimated time of arrival information. The vehicle on-board unit basically has a destination input section, a historical data input section and an estimated time of arrival reporting section. The destination input section is used to enter a destination point. The historical data input section provides historical estimated time of arrival information based on a plurality of actual motorist travel times to the destination point. The estimated time of arrival reporting section reports to a user an estimated time of arrival and an accuracy indicator for the estimated time of arrival from the historical estimated time of arrival information.

The invention provides a method for asynchronous positioning of an ultra-wideband sensor network based on compressive sampling. The method comprises the following specific steps that (1) an anchor node 1 broadcasts ultra-wideband pulse 1; (2) other anchor nodes and a TAG node carry out compressive sampling on a received signal to obtain a time of arrival of the pulse 1; (2) the TAG node broadcasts ultra-wideband pulse 2; (4) each anchor node respectively carries out compressive sampling on the received signal, the anchor node 1 records a pulse round-trip time, and other anchor nodes obtain a time of arrival of the pulse 2 and respectively report the two times of arrival to the anchor node 1; and (5) the anchor node 1 computes a coordinate position of the TAG. On one hand, a compressive sampling method is applied to an ultra-wideband sensor network positioning system, and the ultra-wideband pulse is obtained at a sampling rate which is further lower than Nyquist. On the other hand, each node does not need to carry out clock synchronization strictly, the complexity is lower, and a positioning error of an asynchronous ultra-wideband system can be effectively reduced.

The invention discloses an unknown period acoustic beacon high-precision positioning method based on an underwater maneuvering platform. The method comprises the following steps: step 1, estimating asignal arrival time and a period number; step 2, selecting a positioning period and calculating a second-order time delay difference; step 3, carrying out positioning calculation by utilizing the second-order time delay difference and establishing a positioning calculation equation set according to second-order time delay difference information. The positioning precision can be effectively improved, and high-precision acoustic beacon position coordinates can be obtained.

The damage length measurement system has an object being measured that comprises a plurality of members is vibrated by an oscillator, and the vibration that propagates through the object being measured is detected by three sensors. A measurement apparatus analyzes that vibration wave, and measures the arrival time of the maximum peak. Using the fact that the time for a wave to propagate between two vibration detection sensors separated by a set interval is fixed, the measurement apparatus determines whether the difference in arrival time between two sensors is within a set reference range that includes the vibration propagation time between two vibration sensors. When the measurement apparatus determines that the difference is not within the set reference range, uses the fact that that wave is delayed compared to the wave that was to be detected.