JED - May 2009 - (Page 42)

By Glenn Goodman and John Knowles 42 The Journal of Electronic Defense | May 2009 I n the days and weeks following the September 11 attacks, the US military leadership shifted much of its operational planning focus away from peer competitors like China and Russia and began to consider how to defeat its newest adversary – Al Qaeda. The Department of Defense (DOD) recognized that what was to become the Global War on Terror (GWOT) would depend on intelligence to a greater degree than any previous conflict. Finding targets that rarely used communications (and when they did communicate, it was usually hidden among commercial traffic) would be a challenge, to say the least. US forces were not very well-equipped to monitor (or jam) commercial communications devices, primarily because previous adversaries had never made extensive use of them. The types of communications intelligence (COMINT) technology required to perform surveillance of commercial devices largely had been the responsibility of the National Security Agency. (Other armed forces, such as those of the UK, France and Israel, were somewhat better equipped to monitor commercial communications devices.) What followed over the next several years was a major re-tooling of US tactical COMINT capabilities. The new requirements were challenging. COMINT systems would need to cover more frequencies to track 3G and 4G mobile phones (well above 2 GHz), as well as monitor low-power, push-to-talk (walkie-talkie) communications that could drive receiver requirements down to the 25-MHz region. This trend also demanded that COMINT systems cover a wide variety of commercial waveforms. In addition, selected targets of interest would need to be found from within a vast ocean of commercial communications. With inexpensive cell phones widely available, targets could change devices easily and frequently. This drove requirements for voice recognition and automated language translation capabilities. Since 2001, signals intelligence (SIGINT) system manufacturers have responded to these challenges by developing a new generation of software-defined radio (SDR)-based COMINT systems that cover a wide range of communications frequencies, perform automated searches, process more collected information and use advanced software algorithms to detect and identify targets of interest. Additionally, analysis software also has kept abreast of these developments in the form of improved language translation programs and voice recognition algorithms. At the same time, COMINT manufacturers also have managed to stay abreast of developments in the military communications arena. Today’s COMINT systems monitor military radios that use advanced low-probability of detection (LPD) and low-probability of intercept (LPI) techniques. And networked COMINT systems, featuring time difference of arrival and frequency difference of arrival techniques, are enabling commanders to detect and locate emitters in just about any place, from dense signal environments in urban locations to areas that cover hundreds of square miles. US ARMY: PROPHET No program exemplifies the difficulties of staying on top of a rapidly evolving signal environment like the US Army’s Prophet program, its principal ground-based tactical COMINT system. The vehicle-mounted electronic support (ES) sensor

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

JED - May 2009
The View From Here
From the President
The Monitor
Washington Report
World Report
Protecting Helicopters
Ground-Based COMINT Steps Up
Roost Profile
EW 101
AOC News
Index to Advertisers
JED Sales Offices
JED Quick Look

JED - May 2009