Method for detection of signal source using estimation of noise statistics

摘要

A method for noise signal analysis and communication with an underground transmitter. The method comprises the steps of measuring a noise floor when no signal is transmitted from a transmitter, detecting a signal when the transmitter is transmitting, and estimating the noise free component of the signal by removing the noise floor measurement. The measurement of the noise floor and detecting the signal from the transmitter may be done using a root mean square technique. The noise floor measurement can be removed from the measured signal by subtracting the noise floor measurement from the measured signal or alternatively by calculating the square root of the difference between the square of the measured signal and the square of the noise floor measurement. The noise estimation technique may be used in connection with a differential phased shift keying communication scheme or other modulation techniques.

主权项

1. A method for analyzing signals transmitted from a transmitter, the method comprising the steps of:
obtaining a noise measurement at a remote location when no signal is transmitted from the transmitter; transmitting an electromagnetic signal from the transmitter; detecting the electromagnetic signal at the remote location by measuring a detected electromagnetic field transmitted by the transmitter, the detected signal having a noise free component; estimating the noise free component of the detected signal using the noise measurement and a magnitude of the detected signal; and locating the transmitter using the noise free component.