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Active RF Circulators

Award Information

Department of Defense
Defense Advanced Research Projects Agency
Award ID:
Program Year/Program:
2007 / SBIR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
Applied Radar, Inc.
315 Commerce Park Road North Kingstown, RI -
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Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 2
Fiscal Year: 2007
Title: Active RF Circulators
Agency / Branch: DOD / DARPA
Contract: W31P4Q-07-C-0006
Award Amount: $2,249,697.00


The development of broadband high-isolation active circulators with simultaneous transmit and receive (STAR) capabilities would enable increased persistence in intelligence, surveillance and reconnaissance (ISR) systems and allow multiple simultaneous radar modes including SAR, GMTI and AMTI for global and local multifunction and multi-task operations. Previous works in MMIC active circulators demonstrated the concept and feasibility to realize the devices with stringent design requirements in order to achieve broadband and high isolation operation. Various active circulator configurations which are capable of STAR applications have been studied in our Phase I R&D, including a compilation of desired specifications for STAR radar application. The Phase I investigation also considered available device technologies and substrate materials in terms of power handling, frequency, bandwidth, isolation and interface matching. The Phase II effort will extend this work to implement and realize a broadband high-isolation active circulator with STAR and MMIC capabilities. The proposed work will include a trade-space study on the performance sensitivity of the active circulator based on power-to-noise and bandwidth-to-isolation requirements, development of active matching circuitry at antenna interface, development of feedforward cancellation circuits, final selection of foundry technology for device fabrication in terms of high power and low noise Figure (NF) applications, and finally device fabrication and testing. The development of a high-performance MMIC-based circulator will enable system-on-a-chip architectures with high isolation over a relatively wide bandwidth, while minimizing size and cost for phased array radar application.

Principal Investigator:

William Weedon

Business Contact:

William Weedon
Small Business Information at Submission:

210 Airport Street North Kingstown, RI 02852

EIN/Tax ID: 043438479
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No