Lecture du Professeur Eli Brookner au Conservatoire National des Arts et Métiers, 292 rue Saint-Martin, 75003 Paris
21 Octobre 2014
21/10/2014 17:30 - 21/10/2014 20:00

 

 Titre: Phased Array Digital Beamforming : basics, past-accomplishments and amazing-developments and future trends

BEE: The City College of the City of New York, ’53, MEE and DrSc: Columbia University ’55 and ’62.

Dr. Eli Brookner worked at Raytheon Company from 1962 to retirement July 2014. There he was a Principal Engineering Fellow and worked on ASDE-X airport radar, ASTOR Air Surveillance Radar, RADARSAT II, Affordable Ground Based Radar (AGBR), major Space Based Radar programs, NAVSPASUR S-Band upgrade, COBRA DANE, PAVE PAWS, Missile Site Radar (MSR), COBRA JUDY Replacement, THAAD, Brazilian SIVAM, SPY-3, Patriot, BMEWS, UEWR, Surveillance Radar Program (SRP), Pathfinder marine radar, Long Range Radar (upgrade for >70 ATC ARSRs), COBRA DANE Upgrade, AMDR, Space Fence, 3DELRR, FAA NexGen ATC radar program. Prior to Raytheon he worked on radar at Columbia University Electronics Research Lab. [now RRI], Nicolet and Rome AF Lab.

Received IEEE 2006 Dennis J. Picard Medal for Radar Technology & Application “For Pioneering Contributions to Phased Array Radar System Designs, to Radar Signal Processing Designs, and to Continuing Education Programs for Radar Engineers”; IEEE ’03 Warren White Award; Journal of the Franklin Institute Premium Award for best paper award for 1966; IEEE Wheeler Prize for Best Applications Paper for 1998. Fellow of IEEE, AIAA, MSS. Member of the National Academies Panel on Sensors and Electron Devices for Review of Army Research Laboratory Sensors and Electron Devices Directorate (SEDD). Gives courses on Radar, Phased Arrays and Tracking around the world (25 countries). Over 10,000 attended these courses. Banquet/keynote speaker twelve times. >230 papers, talks and correspondences, >100 invited. Six paper reprinted in Books of Reprints (one in two books).

MIMO Radar – Demystified

MIMO will be explained from a physical understanding. This will give insights into MIMO not achievable using complex mathematical explanations.

Contrary to claims made MIMO does not offer orders of magnitude better resolution and accuracy (like x10 or x100 or x1000 better) than conventional arrays. Wrong comparison is being made. Specifically it is made between a MIMO full/thin array system (consisting of a full transmit array and thinned receive array or vice versa) with a system consisting of conventional full transmit and receive arrays. We show that a conventional thin/full array can achieve the SAME accuracy as the MIMO thin/full array. Is there a situation where the MIMO array radar offers a better accuracy than a conventional array radar? Yes. This is achieved with a monostatic MIMO system consisting of full transmit and receive arrays when compared to the same array used conventionally. However, only about a √2=1.414 better accuracy is achieved with this MIMO array radar. The two have the same resolution though. The √2=1.414 improvement in accuracy is important where space a problem. However, it must be traded-off against the complexity of using orthogonal waveforms and need for a much higher processing load when using a MIMO array versus achieving the same √2=1.414 improvement in accuracy with a conventional radar system by increasing the radiated power by just a factor of two or by increasing the receive antenna size by a factor √2=1.414.

Contrary to what may be thought MIMO does not offer an advantage re barrage noise jammers or hot clutter (a jammer signal scattered from the ground) over a conventional array. It does offer a potential advantage re strong clutter because nulls can be adaptively put in the transmit pattern in the direction of the clutter. However this type clutter can be handled in conventional arrays by putting nulls in the direction of the clutter whose location is usually known or can be determined with a clutter map.

Breakthroughs in Radar and Phased-Arrays : This lecture covers: Array basics: electronic scanning, embedded element gain, time delay steering, elements, array factor, u-v space, errors, mutual coupling, feeds; Digital Beam Forming (DBF): Advantages of DBF; Number of bits Nb needed; Reduction of Nb with increasing number of subarrays and sampling rate; Spurious free dynamic range; Grating lobes due to forming multiple beams at the subarray level and due to frequency scanning of subarray; How overlapped subarrays reduces these grating lobes; limited scanning; advances in phased-arrays leading up to the latest amazing developments and future trends future potential, including metamaterials, graphene, DBF, micromachining, very low cost arrays, signal processing

 

 


 

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