Apparatuses and methods for determining the perspective of a receiver of a transmission from the transmitting station are disclosed. The receiver may determine an angle of arrival of the transmission. The angle of arrival may be used to generate perspective information, which may then be transmitted to the transmitting station for use in enhancing recognition and detection of the receiver. In embodiments, the perspective information may comprise an image or images of the receiver generated from a model of the receiver. In embodiments, the transmission may be a millimeter wave transmission.

According to one embodiment, a measuring apparatus includes an ultrasonic transmitter, an ultrasonic receiver and an estimator. An ultrasonic transmitter transmits, as a transmission signal, an ultrasonic beam in a plurality of directions. An ultrasonic receiver receives, as received signals, reflected waves of the transmission signal from the plurality of directions, one received signal including a plurality of reflected waves when the transmission signal is transmitted to one direction of the plurality of directions. An estimator that estimates range information from the received signals, based on preliminarily obtained received signals and a preliminarily obtained distance to

The present disclosure relates to an acoustic position determination system that includes a mobile communication device and at least one base transmitter unit. The mobile communication device is configured to transmit and receive acoustic signals. Due to relative movements between the mobile communication device and the base transmitter unit, frequencies of the received signals shift due to Doppler effect. The mobile communication device is configured to compensate Doppler frequency shifts in the received acoustic signals prior to performing a deconvolution decoding process. The mobile communication device is further configured to compensate Doppler frequency shifts and perform deconvolution decoding process on acoustic signals received from multiple signal transmission paths.

A housing can be wearable by a user. At least one microphone in or on the housing can sense ambient audio and produce at least one time-domain audio signal. The housing can be passive, such that the sensed ambient audio does not include any sound emitted from the housing. A transformation circuit can transform the at least one time-domain audio signal to form at least one frequency-domain audio signal. An identification circuit can identify a spectral feature in the at least one frequency-domain audio signal. A tracking circuit can track a time evolution of the spectral feature. A determination circuit can determine from the tracked time evolution of the spectral feature that the spectral feature corresponds to an object moving toward the housing. An alert circuit can alert the user, in response to the determination circuit determining that the object is moving toward the housing.

An object detection device includes a microphone array that includes a plurality of non-directional microphones, and a processor that processes first sound data obtained by collecting sounds by the microphone array. The processor generates a plurality of items of second sound data having directivity in an arbitrary direction by sequentially changing a directivity direction based on the first sound data, and analyzes a sound pressure level and a frequency component of the second sound data, and determines that an object exists in a first direction in a case where a sound pressure level of a specific frequency, which is included in the frequency component of the second sound data having directivity in the first direction of the arbitrary direction, is equal to or larger than a first prescribed value.

The invention involves using Doppler shift to locate a leak of a signal from an HFC network. The leaked signal includes a component having a nominal frequency. The invention comprises: (a) moving along a drive route in the area of the network; (b) recording a speed at a number of drive-route points along the drive route; (c) at each point, receiving the component at a received frequency; (d) for each point, measuring the received frequency; (e) for each point, determining a measured Doppler shift from a difference between the received and nominal frequencies; (f) estimating a zero Doppler shift and a zero Doppler shift point based on the measured Doppler shifts; and (g) estimating the leak location based on the estimated zero Doppler shift point.

A multiple frequency ping transmitter which can be carried by a pig which is used in an underwater pipeline. The ping transmitter produces a ping chord which includes a plurality of different tone frequencies which are simultaneously transmitted in the ping chord. Procedures are also provided wherein the multiple frequency ping transmitter is used in a system and method for located a pig which is stuck in the underwater pipeline or for determining the relative velocity of a moving pig.

The present disclosure relates to an acoustic position determination system that includes a mobile communication device and at least one base transmitter unit. The mobile communication device is configured to transmit and receive acoustic signals. Due to relative movements between the mobile communication device and the base transmitter unit, frequencies of the received signals shift due to Doppler effect. The mobile communication device is configured to compensate Doppler frequency shifts in the received acoustic signals prior to performing a deconvolution decoding process. The mobile communication device is further configured to compensate Doppler frequency shifts and perform deconvolution decoding process on acoustic signals received from multiple signal transmission paths.