A system for determining a geographical position of a transmitting device is disclosed. In embodiments, the system includes a concentrator device and a plurality of sensors. In embodiments, each sensor may be configured to: receive an emitter signal from a transmitting device; generate a demodulated sequence of the emitter signal; generate a time-of-arrival (TOA) estimate of the emitter signal; and transmit the demodulated sequence and the TOA estimate to the concentrator device. In embodiments, the concentrator may be configured to: receive a first demodulated sequence and a first TOA estimate (TOA.sub.1) from a first sensor; receive a second demodulated sequence and a second TOA estimate (TOA.sub.2), from a second sensor; determine a first arbitrary timing offset (ATO.sub.1) between the first demodulated sequence and the second demodulated sequence; and determine a first differential TOA estimate (TOA.sub.Diff.sub.1) between the first sensor and the second sensor.

A system for determining a geographical position of a transmitting device is disclosed. In embodiments, the system includes a concentrator device and a plurality of sensors. In embodiments, each sensor may be configured to: receive an emitter signal from a transmitting device; generate a demodulated sequence of the emitter signal; generate a time-of-arrival (TOA) estimate of the emitter signal; and transmit the demodulated sequence and the TOA estimate to the concentrator device. In embodiments, the concentrator may be configured to: receive a first demodulated sequence and a first TOA estimate (TOA.sub.1) from a first sensor; receive a second demodulated sequence and a second TOA estimate (TOA.sub.2), from a second sensor; determine a first arbitrary timing offset (ATO.sub.1) between the first demodulated sequence and the second demodulated sequence; and determine a first differential TOA estimate (TOA.sub.Diff.sub.1) between the first sensor and the second sensor.

A power distribution system including a first and second speaker is provided. The first speaker includes (1) a first input receiving a first power signal; (2) a second input receiving a second power signal phase shifted 120 degrees from the first signal; (3) a third input receiving a third power signal phase shifted 120 degrees from both the first and second signal; (4) a first output transmitting the third power signal; (5) a second output transmitting the first power signal; (6) a third output transmitting the second power signal; and (7) a first load coupled to the first and second input. The second speaker includes (1) a first input receiving the third power signal; (2) a second input receiving the first power signal; (3) a third input receiving the second power signal; and (4) a second load coupled to the first and second input.

A power distribution system including a first and second speaker is provided. The first speaker includes (1) a first input receiving a first power signal; (2) a second input receiving a second power signal phase shifted 120 degrees from the first signal; (3) a third input receiving a third power signal phase shifted 120 degrees from both the first and second signal; (4) a first output transmitting the third power signal; (5) a second output transmitting the first power signal; (6) a third output transmitting the second power signal; and (7) a first load coupled to the first and second input. The second speaker includes (1) a first input receiving the third power signal; (2) a second input receiving the first power signal; (3) a third input receiving the second power signal; and (4) a second load coupled to the first and second input.

A system for determining a geographical position of a transmitting device is disclosed. In embodiments, the system includes a concentrator device and a plurality of sensors. In embodiments, each sensor may be configured to: receive an emitter signal from a transmitting device; generate a demodulated sequence of the emitter signal; generate a time-of-arrival (TOA) estimate of the emitter signal; and transmit the demodulated sequence and the TOA estimate to the concentrator device. In embodiments, the concentrator may be configured to: receive a first demodulated sequence and a first TOA estimate (TOA.sub.1) from a first sensor; receive a second demodulated sequence and a second TOA estimate (TOA.sub.2), from a second sensor; determine a first arbitrary timing offset (ATO.sub.1) between the first demodulated sequence and the second demodulated sequence; and determine a first differential TOA estimate (TOA.sub.Diff.sub.1) between the first sensor and the second sensor.

A system for determining a geographical position of a transmitting device is disclosed. In embodiments, the system includes a concentrator device and a plurality of sensors. In embodiments, each sensor may be configured to: receive an emitter signal from a transmitting device; generate a demodulated sequence of the emitter signal; generate a time-of-arrival (TOA) estimate of the emitter signal; and transmit the demodulated sequence and the TOA estimate to the concentrator device. In embodiments, the concentrator may be configured to: receive a first demodulated sequence and a first TOA estimate (TOA.sub.1) from a first sensor; receive a second demodulated sequence and a second TOA estimate (TOA.sub.2), from a second sensor; determine a first arbitrary timing offset (ATO.sub.1) between the first demodulated sequence and the second demodulated sequence; and determine a first differential TOA estimate (TOA.sub.Diff.sub.1) between the first sensor and the second sensor.

An apparatus for detecting group delay information over frequency for a transmission medium has: a receiver for receiving a measurement signal, the measurement signal comprising at least a first carrier signal at a first carrier frequency, a second carrier signal at a second carrier frequency and a third carrier signal at a third carrier frequency; a frequency analyzer for analyzing the reception signal to obtain reception phase information on the first carrier signal, the second carrier signal and the third carrier signal; and a processor for forming a first combined piece of phase information and for forming a second combined piece of phase information, for forming a first piece of group delay information and for forming a second piece of group delay information, and for associating the first piece of group delay information to a first frequency and the second piece of group delay information to a second frequency.

Some aspects of the present disclosure relate to detection of a Phase Hit and, upon detecting the Phase Hit, determining the magnitude and location of the Phase Hit. Detecting the Phase Hit may involve comparing a phase offset difference for successive pilot symbol to a detection threshold. Determination of the detection threshold may involve a Neyman-Pearson binary hypothesis testing (NP-BHT) approach. Once the magnitude and location of the Phase Hit are known, data symbols received after the location may be processed to remove the magnitude of the Phase Hit.

Some aspects of the present disclosure relate to detection of a Phase Hit and, upon detecting the Phase Hit, determining the magnitude and location of the Phase Hit. Detecting the Phase Hit may involve comparing a phase offset difference for successive pilot symbol to a detection threshold. Determination of the detection threshold may involve a Neyman-Pearson binary hypothesis testing (NP-BHT) approach. Once the magnitude and location of the Phase Hit are known, data symbols received after the location may be processed to remove the magnitude of the Phase Hit.

The present disclosure provides a communication device and a skew correction method thereof. The communication device includes a first signal transceiving device and a correction device. The correction device is coupled to the first signal transceiving device through multiple first channels in a correction mode, each of the first channels has multiple first sub-channels. In the correction mode, the first signal transceiving device simultaneously transmits multiple first data through all the first sub-channels of first channels, and the correction device receives the first data through all the first sub-channels to calculate first skew differences of all the first sub-channels, thus calculating first skew differences according to the first skew values.