Delay compensation
11 Assignments
0 Petitions
Accused Products
Abstract
In a discrete tone system, a base station receives a transmission burst from a remote unit being installed that includes delay compensation pilot tones that are uniformly spread throughout the transmission bandwidth. The arrival time transmission burst is not synchronized with the other remote units transmitting to the base station. The base station measures the phase delay of each tone and calculates the delay of the remote unit from the slope of the line of phase angle versus tone frequency. The base station transmits a signal to the remote unit that includes the magnitude and direction of the delay, which allows the remote unit to adapt the timing of its transmission to be synchronized with the other remote units.
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Citations
33 Claims
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1-17. -17. (Canceled)
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18. A transmitted data signal embodied in a carrier wave, the transmitted data signal including computer-executable instructions to perform a method for determining a delay compensation of signals transmitted between at least one remote unit and a base station of a wireless communication network, the method comprising:
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receiving a first signal from the remote unit, the first signal comprising a plurality of delay compensation tones over a uniformly spaced frequency range;
calculating a phase shift difference between an expected phase and the received phase of the first signal for each of the tones;
unwrapping the phase shift difference associated with one or more of the tones;
linearly regressing the phase shift differences and the unwrapped phase shift differences; and
determining a slope of the linearly regressed phase shift differences, the slope being proportional to the delay compensation. - View Dependent Claims (19, 20, 21, 22, 23)
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24. An apparatus for providing signals within a wireless communication network, the apparatus comprising:
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means for providing a first signal to the network, the first signal including delay compensation pilot (DCP) tones comprising frequencies that are spaced through an upper sub-band frequency range and a lower sub-band frequency range;
means for providing a second signal from the network, the second signal including time adjustment data that is determined from a phase difference between an expected phase angle and a received phase angle for each of the tones of the first signal, the phase differences being unwrapped, the unwrapped phase differences being fitted to a line, and a slope of the line being taken; and
means for providing a third signal to the network, wherein a time of transmission of the third signal is configured in accordance with the time adjustment data so that DCP tones of the third signal arrive at the network in phase with each other. - View Dependent Claims (25, 26, 27, 28, 30, 31, 32, 33)
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29. An apparatus for adjusting a time of transmission of a signal from a mobile unit to a base station, the apparatus comprising:
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means for receiving a first signal from the mobile unit, the first signal having a plurality of tones having upper-band and lower-band components over a spaced frequency range;
means for estimating a distance of the mobile unit from the base station to determine an estimated distance;
means for determining a delay measurement relating to phase differences within the tones of the first signal and the estimated distance; and
means for transmitting the delay measurement to the mobile unit, the delay measurement configured to adjust a time of transmission of a second signal from the mobile unit to compensate for a delay existing in the first signal.
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Specification