The Defense Advanced Research Projects Agency (DARPA) often selects its research efforts through the Broad Agency Announcement (BAA) process. This request for information (RFI) is intended to provide details about a possible future DARPA program so that industry feedback can be considered prior to the issuance of a BAA. Responders are invited to provide comment on any or all of the content of this announcement to include suggestions for improving the scope of a possible solicitation in order to ensure that every effort is made to address this important problem. Responses to this request may be used to support development of and, subsequently, be incorporated within a future DARPA Program BAA, to the extent any such information is available for public distribution. The following sections of this announcement contain details of the scope of technical efforts.

Background & Scope

Phased array antennas are crucial to current and future military systems operating from radio frequencies, to microwave, to millimeter-wave frequencies. This RFI takes both a top-down and bottom-up approach to the technologies and components needed to enable the next generation of phased arrays, which for this RFI includes correlation arrays and interferometers. In particular, this RFI concentrates on two aspects of the phased array antennas: 1) in light of envisioned phased array capabilities and applications, what technologies or components are needed; and 2) assessing and advancing the state of beamforming for RF systems. This RFI solicits respondents to submit ideas related to either or both aspects keeping in mind, however, that any resulting DARPA program would be looking beyond research that primarily results in evolutionary improvements to the existing state of practice.

The first aspect of this RFI pertains to system level needs for phased array performance and capabilities. Here DARPA seeks examples of revolutionary approaches, architectures and applications. Respondents should clearly articulate the deficiency or new capability being addressed. A flow down of system level requirements to the component or module level is preferred, but not required. The goal of this first aspect is to present and illustrate the need being addressed or new capability being enabled by the development and demonstration of new technologies, components, and modules. DARPA's vision is to stimulate technology innovations that would culminate in module-level proof-of-concept demonstrations.

The second aspect of this RFI deals with beamforming. To truly harness the power of phased arrays, and enable the very broad bandwidth potential, it is imperative to employ best-in-class beamforming architectures for any given application. In this context, true-time delay (TTD) based beamformers are far superior when compared to their phase shifter based counterparts. Through this RFI, DARPA is soliciting ideas for developing component and module level technologies to support compact and ultra-compact beamforming architectures for phased array antenna systems operating in frequency bands within the range 1 to 100 GHz. Of particular interest to DARPA are technologies and solutions that afford multi-octave bandwidth operation while concurrently enabling multiple beams in different frequency bands from the same aperture. DARPA has significant interest in considering novel beamforming modules and architectures that substantially reduce the size, weight, and power (SWAP) of phased array antenna systems. Technologies that significantly reduce precious aperture wall-plug power are particularly attractive. Approaches to address this problem may include the processing of received signals at a location that is remote from the antenna aperture.

DARPA solicits respondents to submit ideas related to this topic for use by the Government in formulating a potential program. DARPA requests that submittals briefly and clearly describe the potential approach or concept, outline critical technical issues, and comment on the expected performance, robustness, affordability, weight, size and power requirements of the proposed approach. The Government does not intend to award a contract on the basis of this RFI or to otherwise pay for the information solicited, nor is the Government obligated to issue a solicitation based on responses received. Responses should be limited to three pages for any given concept. Any proprietary concepts or information should be clearly identified as such. Input on technical aspects of the responses may be solicited by DARPA from non-Government consultants/experts who are bound by appropriate non-disclosure requirements. For all RFI responses, an additional, non-proprietary cover page is also requested identifying your company name, technical point of contact and contact information. In order to comply with scheduling priorities, responders are asked to provide feedback by no later than 2:00pm (Eastern) April 18, 2008. RFI Responses should be submitted in a commonly used electronic format and may be e-mailed or mailed on a CD-ROM to: Dr. Ronald Esman, Program Manager (Primary RFI Technical Point of Contact), DARPA/MTO, 3701 N Fairfax Dr. Arlington, VA 22203. E-mail: ronald.esman@darpa.mil Phone (571) 218-4691, Fax (703) 248-1817.