Direct-to-digital software-defined radar

• US 9,024,815 B2
• Filed: 05/29/2012
• Issued: 05/05/2015
• Est. Priority Date: 05/27/2011
• Status: Active Grant

• Current Assignee: Brooks Engineering International, LLC
• Original Assignee: Brooks Engineering International, LLC
• Inventors: Brooks, John W.
• Primary Examiner(s): Sotomayor, John B
• Assistant Examiner(s): WINDRICH, MARCUS E
• Application Number:
  US13/482,022
• Publication Number:
  US 20120313813A1
• Time in Patent Office: 1,071 Days
• Field of Search: 342/22, 342/162, 342/195
• US Class Current: 342/195
• CPC Class Codes: G01S 7/20 Stereoscopic displays; Three-dimensional displays; Pseudo-three-dimensional displays
• CPC Class Codes: G01S 7/288 Coherent receivers

Abstract

A direct-to-digital software defined radar system includes a high-speed digitizer coupled directly to a receive antenna and outputs a digital signal to a processor which receives the digitized signal, along with an arbitrarily-defined reference signal provided by signal generator, and indexes the signal data according to time and geo-location, arranges the data according to a three-dimensional data structure, declutters and filters and refines the data for storage or display.

Claims

1. A radar system comprising:

a receive antenna having an output comprising a received signal;

an arbitrary waveform generator for providing an arbitrarily defined waveform signal, said arbitrary waveform generator having an output comprising a first reference signal corresponding to said received signal;

an analog-to-digital convertor having a first input directly coupled to said received signal and configured to the output of said receive antenna for the purpose of converting said received signal to a digital received signal;

a computer-based adaptive processor having a first input for receiving said digital received signal and a second input for receiving said first reference signal, said processor being configured with a computer-readable media with control logic stored thereon which causes said adaptive processor to perform a process comprising the steps of;

i. obtaining digitized signal data by correlating said first digital signal with a digitized first reference signal;

ii. obtaining geo-indexed data by identifying said digitized data according to geo-location data from a geo-positioning device;

iii. arranging said geo-indexed data according to a three-dimensional information structure, said structure comprising three of the following data parameters;

range, depth, azimuth, elevation, pulse width, pulse repetition interval, range gate, scan length, antenna element, and cross-range;

iv. decluttering said arranged data; and

v. migrating said arranged data.

2. The radar system of claim 1, further comprising a pulse generator having an output comprising a second reference signal and wherein said adaptive processor unit further comprises an input for receiving a digitized second reference signal.

3. The radar system of claim 2, wherein said step of obtaining digitized signal data comprises correlating said first digital signal with either of said digitized first reference signal and said digitized second reference signal.

6. The radar system of claim 1, further comprising a low noise amplifier interposed between said antenna and said analog-to-digital converter.

4. A radar system consisting essentially of:

a signal waveform generator for providing a transmit signal that is arbitrarily defined, and a reference signal corresponding to said transmit signal;

a transmit antenna for coupling said transmit signal to a transmission medium;

a receive antenna for coupling a reflected transmit signal from said transmission medium to a receiver and outputting a received signal, said received signal corresponding to said transmit signal;

one or more high-speed digitizers directly responsive to said receive antenna for converting said received signal into a digitized received signal and for converting said reference signal into a digitized reference signal;

a processor responsive to said digitizer and said waveform generator, said processor configured with control logic which, when executed, performs the steps of;

i. obtaining digitized received signal data by correlating said digitized received signal with said digitized reference signal;

ii. indexing said digitized received signal data with time and geo-location data from a geo-positioning device;

iii. arranging indexed data according to a data structure, said data structure configured to reference said indexed data according to at least three parameters consisting of range, depth, azimuth, elevation, pulse width, pulse repetition interval, range gate, scan length, antenna element, and cross-range; and

iv. decluttering said arranged data by eliminating data indicative of non-target reflections.

5. The radar system of claim 4, wherein said processor is configured with control logic which, when executed, causes the processor to further perform the step of:

refining detected target data.