Abstract: An acoustic model determination approach for a real-time locating system is disclosed. The system includes one or more transmitting devices and one or more mobile devices. The acoustic model may be determined by deriving an acoustic representation of sub-structures within the building, and then forming the acoustic model based on the acoustic representation and the location and orientation of the static acoustic transmitting device. In another embodiment, an acoustic signal is transmitted from a static acoustic transmitting device, with the reflected signals received by the same static acoustic transmitting device in a receiving mode. Based on these received acoustic signals, the acoustic model is formed based on the reflected signals and the location and orientation of the static acoustic transmitting device.

Abstract: An approach to obtain low latency association of the audio clock in a smartphone with an incoming RF message is to use an interrupt driven routine, where the receipt of the RF message preamble generates an interrupt that reads the audio clock counter since the start of the audio session. In some embodiments such an approach may be implemented on the specialized processing cores found in smartphones that control RF communication, sensor or audio processing.

Abstract: An acoustic model determination approach for a real-time locating system is disclosed. The system includes one or more transmitting devices and one or more mobile devices. The acoustic model may be determined by deriving an acoustic representation of sub-structures within the building, and then forming the acoustic model based on the acoustic representation and the location and orientation of the static acoustic transmitting device. In another embodiment, an acoustic signal is transmitted from a static acoustic transmitting device, with the reflected signals received by the same static acoustic transmitting device in a receiving mode. Based on these received acoustic signals, the acoustic model is formed based on the reflected signals and the location and orientation of the static acoustic transmitting device.

Abstract: An approach to obtain low latency association of the audio clock in a smartphone with an incoming RF message is to use an interrupt driven routine, where the receipt of the RF message preamble generates an interrupt that reads the audio clock counter since the start of the audio session. In some embodiments such an approach may be implemented on the specialized processing cores found in smartphones that control RF communication, sensor or audio processing.

Abstract: An approach to obtain low latency association of the audio clock in a smartphone with an incoming RF message is to use an interrupt driven routine, where the receipt of the RF message preamble generates an interrupt that reads the audio clock counter since the start of the audio session. In some embodiments such an approach may be implemented on the specialized processing cores found in smartphones that control RF communication, sensor or audio processing.

Abstract: An approach to obtain low latency association of the audio clock in a smartphone with an incoming RF message is to use an interrupt driven routine, where the receipt of the RF message preamble generates an interrupt that reads the audio clock counter since the start of the audio session. In some embodiments such an approach may be implemented on the specialized processing cores found in smartphones that control RF communication, sensor or audio processing.

Abstract: The present disclosure relates to a location determination system that includes acoustic transmitting devices and mobile devices. A mobile device receives acoustic signals (e.g., ultrasound signals) from an acoustic transmitting device. The mobile device must be able to identify the acoustic transmitting device with particularity when receiving the acoustic signals. It is more efficient to use a short identifier, for example 6 bits, for this purpose because it requires less power to transmit and decode. By utilizing the rotating identifier system described herein, more acoustic transmitting devices can be distinguished than using a time-invariant identifier would otherwise provide, and the transmissions are more secure and therefore less vulnerable to free-riders.