Methods, apparatus, systems, and articles of manufacture to determine a location of an audio source are disclosed. Disclosed example apparatus are to determine respective error values for corresponding ones of a first dataset of time difference of arrival (TDOA) distance values between pairs of acoustic sensors, the error values based on a cost function, a first set of constraints and a second set of constraints. Disclosed example apparatus are also to adjust the corresponding ones of the first dataset of TDOA distance values based on the respective error values to determine a second dataset of TDOA distance values. Disclosed example apparatus are further to output the second dataset of TDOA distance values to source location circuitry that is to determine the location of the audio source.

Methods, apparatus, systems, and articles of manufacture to determine a location of an audio source are disclosed. Disclosed example apparatus are to determine respective error values for corresponding ones of a first dataset of time difference of arrival (TDOA) distance values between pairs of acoustic sensors, the error values based on a cost function, a first set of constraints and a second set of constraints. Disclosed example apparatus are also to adjust the corresponding ones of the first dataset of TDOA distance values based on the respective error values to determine a second dataset of TDOA distance values. Disclosed example apparatus are further to output the second dataset of TDOA distance values to source location circuitry that is to determine the location of the audio source.

A method includes establishing, for a given time, measurement biases allowing an error affecting raw measurements of pseudoranges separating a navigation unit from at least three beacons to be decreased, and estimating an external position of the navigation unit at the given time based on: beacon positions, corrected pseudorange measurements computed for the given time using established measurement biases, and a preceding external position of the navigation unit estimated for a time preceding the given time. The measurement biases are established without taking into account the external position of the navigation unit.

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.

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 method, computer program product, and computing system for encoding audio encounter information of a reference audio acquisition device of a plurality of audio acquisition devices of an audio recording system, thus defining encoded reference audio encounter information. Location information may be estimated, via a machine vision system, for an acoustic source within an acoustic environment. One or more acoustic relative transfer functions may be selected from a plurality of acoustic relative transfer functions for the plurality of audio acquisition devices of the audio recording system based upon, at least in part, the location information. The encoded reference audio encounter information and a representation of the selected one or more acoustic relative transfer function may be transmitted.

A method and system for enabling the determination of a position of a receiver within a space includes transmitting a beacon signal from each of a plurality of beacon devices located at different locations within the space. The beacon signal transmitted from each beacon device has a unique information component and may have a unique frequency pattern of multiple frequencies. Each beacon signal can be distinguishable from the beacon signals transmitted from any other of the beacon devices based on the combination of its unique information component and its unique frequency pattern. The beacon signals are received at a receiver. At the receiver, for each beacon signal of a working subset, time-delay information of the received beacon signal is determined and multilateration is applied to determine the position of the receiver based on the location of each beacon device of the working subset.

A method and system for enabling the determination of a position of a receiver within a space includes transmitting a beacon signal from each of a plurality of beacon devices located at different locations within the space. The beacon signal transmitted from each beacon device has a unique information component and may have a unique frequency pattern of multiple frequencies. Each beacon signal can be distinguishable from the beacon signals transmitted from any other of the beacon devices based on the combination of its unique information component and its unique frequency pattern. The beacon signals are received at a receiver. At the receiver, for each beacon signal of a working subset, time-delay information of the received beacon signal is determined and multilateration is applied to determine the position of the receiver based on the location of each beacon device of the working subset.

Disclosed herein are systems and methods for acoustic navigation. The acoustic navigation system includes a surface component installed on a vessel and a subsurface component positioned on the seafloor. The surface component includes acoustic transducer and acoustic transceiver units configured to generate and transmit an omnidirectional acoustic interrogation signal and directionally receive acoustic reply signals. The subsurface component includes a plurality of seafloor platforms placed at known geodetic locations on the seafloor. Each seafloor platform includes an acoustic transducer unit and an acoustic signal processing unit and is configured to receive and process the acoustic interrogation signals and generate and transmit an omnidirectional acoustic reply signal. The surface component is further configured to receive and process the acoustic reply signals, to calculate the geodetic location and heading of the vessel, and to display the geodetic location and heading information on a human machine interface.

Disclosed herein are systems and methods for acoustic navigation. The acoustic navigation system includes a surface component installed on a vessel and a subsurface component positioned on the seafloor. The surface component includes acoustic transducer and acoustic transceiver units configured to generate and transmit an omnidirectional acoustic interrogation signal and directionally receive acoustic reply signals. The subsurface component includes a plurality of seafloor platforms placed at known geodetic locations on the seafloor. Each seafloor platform includes an acoustic transducer unit and an acoustic signal processing unit and is configured to receive and process the acoustic interrogation signals and generate and transmit an omnidirectional acoustic reply signal. The surface component is further configured to receive and process the acoustic reply signals, to calculate the geodetic location and heading of the vessel, and to display the geodetic location and heading information on a human machine interface.