Apparatus and method of time delay estimation
AssigneeTellabs Operations, Inc.
InventorMaurice Givens
Life of this patent
Estimating the term…
Abstract
An apparatus and method for estimating a time delay between two signals are provided. An original signal and a delayed signal are provided to an average magnitude difference processor for determining an average magnitude difference for a sum of samples representing an envelope of each of the respective original and delayed signals, each for a series of sample delays. The time delay between the two signals is determined as the sample delay which minimizes the average magnitude difference.
Claims34
A method of processing telecommunications signals comprising the steps of:
- transforming an original signal to produce an absolute value of the original signal;
- transforming a delayed signal to produce an absolute value of the delayed signal;
- applying a low pass filter to the absolute value of the original signal to provide an original-signal envelope estimate;
- applying a low pass filter to the absolute value of the delayed signal to provide a delayed-signal envelope estimate;
- and
- applying a delay estimation function to the original-signal envelope estimate and the delayed-signal estimate to provide an estimate of the delay between the original signal and the delayed signal.
A method of processing telecommunications signals comprising the steps of:
- transforming an original signal to produce an absolute value of the original signal;
- transforming a delayed signal to produce an absolute value of the delayed signal;
- applying a low pass filter to the absolute value of the original signal to provide an original-signal envelope estimate;
- applying a low pass filter to the absolute value of the delayed signal to provide a delayed-signal envelope estimate;
- applying a delay estimation function to the original-signal envelope estimate and delayed-signal envelope estimate to provide an estimate of the delay between the original signal and the delayed signal.
An apparatus for estimating a delay in a telecommunication signal comprising:
- an absolute value generator for producing an absolute value of an original signal and an absolute value of a delayed signal;
- a filter means connected with the absolute value generator for altering the absolute value of the original and the delayed signals to provide an estimate of the original-signal envelope and the delayed-signal envelope;
- and
- a delay estimation means for receiving the signal envelopes and for estimating the delay between the original signal and the delayed signal from the reduced original-signal envelope and the reduced delayed-signal envelope.
An apparatus for estimating a delay in a telecommunication signal comprising:
- a sample reduction means for reducing the sampling rate of an original signal and a delayed signal;
- an absolute value generator connected with the sample reduction means for producing an absolute value of the reduced original signal and an absolute value of the reduced delayed signal;
- a filter means connected with the absolute value generator for altering the absolute value of the reduced original signal and the reduced delayed signal to provide an estimate of the original-signal envelope and the delayed-signal envelope;
- and
- a delay estimation means for receiving the signal envelopes and for estimating the delay between the original signal and the delayed signal from the original-signal envelope estimate and the delayed-signal envelope estimate.
Dependencies are inferred from the claim text.