1. AAVP meeting Cambridge December 2010 Technology Trade –offs: Mid band Array and Elements Prof. A. K. Brown 1 1 School of Electrical and Electronic Engineering The University of Manchester, PO Box 88, Manchester, M13 9PL, U.K.

2. AA-mid 400MHz-1.4GHz Wide angle, high sensitivity, multiple beam forming: ~100’s square degrees High survey speeds High dynamic range capability Polarimetry

3. Element size/type Array Geometry Antenna Array (Array Geometry,element type) Element Impendence, variation with frequency and scan Balanced/unbalanced feed Low Noise Amplifier Frequency sensitive weights “Calibratability” Coupled noise (relates to geometry and LNA S 11 LNA) Beamformer design Mutual Coupling

4. Sensitivity scan angle Dynamic Range Sidelobe level Stability/calibration (scan angle and sensitivity) Polarimetry Calibration accuracy Frequency/angular effect Minimise Cost /Power Minimise N Infrastructure cost Data transport Through life costs: MTBF/MTCF/MTTR etc Sidelobe level Bandwidth

7. EMBRACE Antenna development Mechanics evolved toward trustworthy and producible antenna element.

8. Printed Vivaldi

9. Planar structure The rings are attached to the surface of the expanded polystyrene foam (EPS) with a defined separation between two layers and the groundplane

10. Polarimetry- frequency/scan angle dependance LNA selection- noise, balance/unbalanced, power requirements etc Cost reduction/production engineering/environmental analysis Tie down the reliability analysis, LRU policy etc

11. Come a long way during SKADS –Downselected to two basic types, one at a more advanced stage of technological readiness, the other offering possibly further cost reductions and different detailed electro-magnetics –Choice and design of LNA critical – eg shielding requirements, physical size etc –1 st quarter next year technology review EMRACE development plus background research programme will prove a crucial tool

12. Thank you!

13. COBRA DANE Mid1970’s

14. Dual Polarization Vivaldi Good radiation Anomaly