Abstract: Embodiments are disclosed for crash detection on one or more mobile devices (e.g., smartwatch and/or smartphone). In some embodiments, a method comprises: detecting, with at least one processor, a crash event on a crash device; extracting, with the at least one processor, multimodal features from sensor data generated by multiple sensing modalities of the crash device; computing, with the at least one processor, a plurality of crash decisions based on a plurality of machine learning models applied to the multimodal features; and determining, with the at least one processor, that a severe vehicle crash has occurred involving the crash device based on the plurality of crash decisions and a severity model.

Abstract: A method and apparatus are provided for easily and accurately calibrating an antenna array in a multipath environment. A calibration table containing spatial signature data together with corresponding location data is used to calibrate the antenna array, i.e. to determine the array response in various directions. The calibration table includes a set of calibrated signal covariances R1, . . . , RN together with a set of N corresponding geographical locations. From this data, a set of array calibration vectors {a(&thgr;)} is determined, where each vector a(&thgr;) characterizes the complex signal response of the antenna array in the direction &thgr;. Once the array calibration vectors are determined, this information can be used for direction finding, beamforming, and other enhancements to the performance of the communication system.

Abstract: A method for determining a geographical location from a measured wireless signal signature comprises calculating from the measured wireless signal signature a multi-dimensional signature vector, wherein each component of the vector measures a degree of coincidence between the measured wireless signal signature and a calibrated signal signature stored in a calibration table. The method also includes matching the signature vector with vectors in a set of multi-dimensional calibrated vectors. The matching uses a procedure comprising searching a hierarchical tree structure and eliminating nodes that cannot contain the best match vector. Within the remaining nodes, the search eliminates individual vectors that cannot be the best match vector, and selects one or more vectors in the set of multi-dimensional calibrated vectors, where the matched vectors correspond to calibrated geographical locations.

Abstract: A system and method is provided for processing a calibration table used in a wireless location finding system. The initial calibration table data comprises points partitioned into routes followed by moving vehicles, where each point comprises a wireless signal signature and corresponding geographical location. The method comprises calculating, for each point, a list of neighboring points; and generating, for each route, a plurality of geographical bins covering all points in the route. Each bin has a bin location and a bin signature derived from those of the points within the bin. The resulting calibration table, which contains fewer redundant data points than the original calibration table data, may be used in a location finding system for quickly identifying the location of wireless transmitters in real time.

Abstract: A method for improving the accuracy of signal signature determinations in wireless location finding systems advantageously uses transmitter velocity estimates to accurately and reliably determine in real time a present signal covariance matrix for a transmitter. In a preferred embodiment of the invention, a method for determining a likely location of a transmitter in a wireless transmitter location finding system comprises coherently measuring transmitter signals received at an antenna array, and calculating a current signal covariance matrix from the measured transmitter signals. The method further comprises calculating an average covariance matrix by forming a linear combination of the current signal covariance matrix with past average covariance matrices.

Abstract: The insertion effects of hearing aids are determined and compensated to restore the ability to have directional hearing in individuals wearing hearing aids. In one aspect a method involves finding the ratio of the unaided head related transfer function to the aided head related transfer function and then designing a hearing aid filter that is the inverse of that derived insertion effect, thereby restoring the ability to hear interaural differences in aided systems both in level and in time of arrival to improve hearing in the presence of noise. The insertion effects can be derived either through frequency domain analyses, using the above-mentioned transfer function calculations and measurements, or in another aspect through time domain analyses, using optimal filter calculations and measurement obtained using a successive data acquisition system that is subsequently time aligned by recording trigger pulses with the data.