US 2006/0140054 A1 · Noise adaptive sonar signal processor

Abstract

A system and method of performing sonar range estimations in a noisy sonar environment. The system includes a sensor, a transmitter, a receiver, a plurality of band-pass filters, a cross correlator, and a data analyzer. The transmitter transmits a pulse through a transmission medium. The pulse travels through the transmission medium until it strikes an object, which returns an echo to the sensor. The sensor provides the echo to the receiver, which provides an indication of the echo to the band-pass filters. The respective band-pass filters provide filtered versions of the echo and pulse to the cross correlator, which performs multiple cross correlation operations on the filtered echo and pulse. The cross correlator provides output data to the data analyzer, which uses the data to estimate the SNR in the environment and to determine a pulse center frequency corresponding to the estimated SNR. By controlling the center frequency of pulses emitted by the transmitter based on information provided by the data analyzer, the system obtains sonar range estimations with increased accuracy.

Claims30

Dependent claims

A system for estimating a range of at least one object in an environment, comprising:

a transmitter configured to transmit at least one first signal through a predetermined transmission medium within the environment, the first signal having a predetermined frequency range and an associated center frequency, wherein the first signal travels through the transmission medium until it strikes at least one object, thereby generating at least one second signal reflected from the object;
and
a sub-system including a cross correlator, the cross correlator being operative to receive representations of the first and second signals, and to perform at least one cross correlation operation on the first and second signals to detect at least one cross correlation peak, the sub-system being operative to estimate the range of the object based on the detected cross correlation peak,
wherein the sub-system is further operative to estimate a signal-to-noise ratio (SNR) in the environment, the SNR being at least partially dependent upon the frequency associated with the first signal, and to control the transmitter to dynamically change at least the frequency associated with the first signal based on the estimated SNR.

1 more element

A method of estimating a range of at least one object in an environment, comprising the steps of:

transmitting at least one first signal through a predetermined transmission medium within the environment by a transmitter, the first signal having a predetermined frequency range and an associated center frequency, wherein the first signal travels through the transmission medium until it strikes at least one object, thereby generating at least one second signal reflected from the object;
receiving representations of the first and second signals by a cross correlator;
performing at least one cross correlation operation on the first and second signals to detect at least one cross correlation peak by the cross correlator;
estimating the range of the object based on the detected cross correlation peak;
estimating a signal-to-noise ratio (SNR) in the environment, the SNR being at least partially dependent upon the frequency associated with the first signal;
and
controlling the transmitter for dynamically changing at least the frequency associated with the first signal based on the estimated SNR.

4 more elements

Dependencies are inferred from the claim text.

Noise adaptive sonar signal processor

Life of this patent

Noise adaptive sonar signal processor

Life of this patent

Abstract

Claims30