JED - September 2009 - (Page 15)

the The Strategic Technology Office at the Defense Research Projects Agency (DARPA) has issued a Broad Agency Announcement (BAA 09-65) for the Precision Electronic Warfare (PREW) program. DARPA wants to develop a highly surgical electronic attack capability that focuses energy from a distributed array of low-power jamming nodes (40 or more, according to the solicitation) to attack navigation and communications receivers while minimizing the effects on nearby friendly and neutral systems. According to the BAA, the PREW system would use small, lightweight (notionally less than 5 lbs.), low cost nodes mounted on a slow moving or stationary aircraft or in advantageous ground positions. The nodes will be formed into an ad-hoc network and use precision timing techniques to collectively focus their low-power jamming energy on target locations as precise as “a city block corner” with minimal impact on the surrounding area. The desired frequency range is 200-2,700 MHz. Target systems are described in a classified index. monitor news DARPA envisions the system will operate in one of two electronic attack modes: “point to an area” or “point to a spot.” The “point to a spot” mode will rely on some type of passive or active beacon(s) near the target area (or within the network area) that would provide reference information on the target location. This closed-loop approach could use a beacon that is cooperative or one that is not aware it is serving this purpose. The BAA also states, “Clock synchronization represents a significant challenge in this effort. Synchronization can be accomplished in various ways including round trip synchronization, full feedback, 1-bit feedback, location-based and retroreflective techniques.” Additionally, the PREW program “restricts the techniques to simple methods such as injecting wideband or narrowband energy into a digital receiver to disable communications. The effect need not be saturation of the receiver front end, but should reduce the communications or navigation receiver Quality of Service (QoS) to a useless level.” DARPA envisions the system will have the following minimal set of organic capabilities: localization; intra-node communication link for coordination; command and control communication link; synchronization; processing for spatial and temporal jamming; and energy transmission. In terms of node design, two key design drivers are the number of target signals it can attack and the unit’s size, weight, power and cost. The BAA covers the first two of three anticipated program phases. During Phase 1, the contractor will develop and demonstrate “clock synchronization across the array, pointing accuracy, energy coherence at 10 km range and collateral interference minimization.” Phase 2, which could be exercised as a contract option, will focus on designing an “airborne-based array node” and pointing the coherent energy from the array at the target area. The contractor also must demonstrate “low impact” to friendly receivers operating in the jamming frequency bands and outside the specific target area. continued on page 17 The Journal of Electronic Defense | September 2009 DARPA SOLICITS BIDS FOR “SURGICAL JAMMER” 15 GROWLER ENTERS SERVICE The US Navy’s new Boeing EA18G Growler support jamming aircraft, following completion of its three-month Operational Evaluation and a subsequent test report, was declared operationally effective and suitable in late July and recommended for fleet introduction by the service’s independent Operational Test and Evaluation Force. This clears the way for a full-rate production decision. The first EA18G electronic attack squadron, VAQ-132, is scheduled to become operational this month. The Navy currently plans to buy 88 Growlers to replace all of its carrier-based EA6B Prowlers by 2013. – G. Goodman

Table of Contents for the Digital Edition of JED - September 2009

JED - September 2009
The View From Here
From the President
The Monitor
Washington Report
World Report
Defeating Threats to Large Aircraft
The Threat Test Resource Gap
EW 101
AOC News
JED Sales Offices
Index of Advertisers
JED Quick Look

JED - September 2009