Adaptive moving target indicator (MTI) clutter rejection filter for radar systems
First Claim
1. Apparatus for providing moving target indicator (MTI) filtering in the presence of clutter for a radar receiver employing digital pulse compression to provide at an output a compressed digital pulse for application to the input of a MTI digital filter, comprising:
- a digital adaptive filter of the same weight as said MTI filter and operative to receive said compressed pulse to provide at outputs of said filter a set of weighted filter coefficients;
a comparator configured to compare a level of clutter with a predetermined threshold level; and
a control module responsive to said comparator configured to apply said weighted coefficients to said MTI filter when said level of clutter exceeds said predetermined threshold.
2 Assignments
0 Petitions
Accused Products
Abstract
Apparatus for providing moving target indicator (MTI) filtering in the presence of clutter for a radar receiver employing digital pulse compression to provide at an output a compressed digital pulse for application to the input of a MTI digital filter, including a digital adaptive filter of the same weight as the MTI filter and operative to receive the compressed pulse to provide at outputs of the filter a set of weighted filter coefficients, wherein the weighted coefficients are applied to the MTI filter during a predetermined clutter mode.
38 Citations
11 Claims
-
1. Apparatus for providing moving target indicator (MTI) filtering in the presence of clutter for a radar receiver employing digital pulse compression to provide at an output a compressed digital pulse for application to the input of a MTI digital filter, comprising:
-
a digital adaptive filter of the same weight as said MTI filter and operative to receive said compressed pulse to provide at outputs of said filter a set of weighted filter coefficients; a comparator configured to compare a level of clutter with a predetermined threshold level; and a control module responsive to said comparator configured to apply said weighted coefficients to said MTI filter when said level of clutter exceeds said predetermined threshold. - View Dependent Claims (2, 3, 4, 5)
-
-
6. Apparatus for providing moving target indicator (MTI) filtering in the presence of clutter for a radar receiver employing digital pulse compression to provide at an output a compressed digital pulse for application to the input of a MTI digital filter, comprising:
-
a digital adaptive filter of the same weight as said MTI filter and operative to receive said compressed pulse to provide at outputs of said filter a set of weighted filter coefficients, wherein said weighted coefficients are applied to said MTI filter during a predetermined clutter mode according to a switch, where said switch is operative in a first mode for applying a set of conventional weight coefficients to said MTI filter and operative in a second mode to apply said weighted coefficients from said adaptive filter to said MTI filter; and a threshold detector responsive to detected clutter to provide at an output a signal indicative of clutter above a predetermined level, said detector coupled to said switch to operate said switch in said second state to apply said weighted coefficients to said MTI filter.
-
-
7. A method for providing moving target indicator (MTI) filtering in the presence of clutter for a digital pulse compression radar receiver having a digital MTI filter of the type including a N stage shift register with the output of each stage coupled to the input of an associated multiplier with another input of each multiplier receiving a coefficient for determining the filter response during radar operation;
- the method comprising the steps of;
calculating coefficients for each multiplier; comparing a level of clutter to a predetermined threshold value; determining if said level of clutter exceeds said threshold value; applying said calculated coefficients to said multipliers when said clutter level exceeds said threshold value; and applying another set of coefficients to said multipliers when said clutter level does not exceed said threshold value. - View Dependent Claims (8, 9)
- the method comprising the steps of;
-
10. A method for providing MTI filtering in the presence of clutter for a radar receiver employing digital pulse compression to provide at an output a compressed digital pulse for application to the input of a N state digital MTI filter, comprising the steps of:
-
using an adaptive digital filter of N stages, applying said compressed digital pulse to the input of said adaptive digital filter to cause said adaptive digital filter to provide a set of N filter coefficients, detecting a level of clutter from a radar clutter map and comparing the detected level to a given threshold, and applying said set of N filter coefficients to said MTI filter when said detected level exceeds said threshold. - View Dependent Claims (11)
-
Specification