Sunday, October 05, 2008

U.S. Radar In Israel: What's It For, Really?


U.S. Radar In Israel: What's It For, Really? (Updated)

By Noah Shachtman
October 03, 2008 9:28:00 AM
Categories:
Missiles, Mullah Menace, Sabras
Courtesy Of
Wired Blog Network

A few weeks back, the U.S. Army's European Command set up an early-warning radar system in Israel. It's ostensible purpose is to boost defenses against Iranian missiles. But Entropic Memes wonders whether there isn't something more to this radar than meets the eye.

The AN/TPY-2 radar is one of the "key component[s]" in the "American Forward-Based Radar global missile-defense system," Entropic Memes notes. And it has a huge range -- about 2000 kilometers, by some estimates.

Placed in Israel, the radar could watch over most of Iran. But it also covers a broad swath of the Middle East and the Caucasus, too. Plus, EM observes, "you can’t help but wonder why the system wasn’t installed in Iraq, or better yet Afghanistan." That "would ensure full coverage of Iran - and, in the case of Afghanistan, provide coverage of Pakistan as well."

What's more, the system in Israel is quite similar to the radar that the U.S. wanted so badly to install in the Czech Republic earlier this year, as part of its larger missile defense shield. Could this be another attempt, to piece together that regional defense? Victoria Samson, with the Center for Defense Information, believes it might. "It was sold to the Israelis as something that could feed information into their system about incoming Iranian missiles," she writes. "But I would argue its primary purpose is to be part of the U.S. missile defense system in Europe."

CIA veteran Allen Thomson is "not convinced," however. Israel Negev desert "is marginal as a site to provide coverage of Iranian launches to the north, particularly if you factor in earth curvature and the altitude missiles launched from Iran would have to get to to break the radar's horizon. The Caucasus or even eastern Turkey would be much better," he tells DANGER ROOM.

Thomson adds, "That said, I agree that very careful (meaning quantitative) scrutiny should be given to this deployment to see if it makes sense in terms of its claimed purpose. Or in terms of other, unclaimed purposes."

UPDATE: Be careful about those radar range estimates, former Air Force officer Brian Weeden counsels. They vary quite a bit.

First, range is function of the power of the radar. Modern phased arrays are made of a number of smaller transmit/receive elements, often times hundreds or thousands depending on the size of the radar face and the width of the radar beam (a function of the frequency). The total power (and thus range) of the radar depends on how many of these elements you pack into the face. There's a huge difference in capability between a fully populated array and one that's only 10% populated, and it looks like MDA isn't going to have nearly the money or manufacturing capacity to fully populate the elements either the Israel or Czech radar (10 to 25% populated is more likely).

Second, effective tracking range of a radar is dependent on the
Radar Cross Section (RCS) of the object it is trying to track (which is partly dependent on the frequency of the radar). This makes sense - the more radar reflective an object is, the more energy it will reflect back to the receiver and thus less power is needed to track it. So whenever someone gives you the "effective range" of a radar, you always need to ask "against what size target?" And here once again MDA isn't really being completely honest. The stated ranges for the Israel and Czech (and Sea Based X-band for that matter) are against 1 meter RCS targets. Unfortunately, their primary target - nuclear warheads in flight - are much smaller than that in the frequency the are using, typically about 0.1 meter RCS.

Bottom line? Read the fine print before believing any of these range estimates.

No comments: