The ever reliable Bill Sweetman points us toward an Air Power Australia (APA) analysis of the stealth capabilities of the F-35 JSF.
The folks at APA have an agenda, and they have been very clear on it, they like the F-111 and F-22 for Australian service, and do not like the F/A-18 and the F-35, so that is a part of the subtext, but they have have a bit of a first in their analysis here, they have, “used publically available radar scattering models,” to get a first order approximation of the performance of the F-35 in various frequency bands.
The science has been known for some time, but actual computer codes available publicly are a fairly recent development.
They make it clear that this is an accounting of the shape, because information on RAM (radar absorbent material) is classified, Mr. Sweetman is right when he quotes Stealth pioneer Denys Overholser, who said, “the four most important aspects of stealth are shape, shape, shape and materials.”
Also note that the Russian double digit SAMs were largely developed post Gulf War, when it was clearly shown that higher frequency radars, particularly in the X-band, were the most vulnerable to a stealth, and that in a modern combat environment, you can not sit there with an air defense radar radiating looking for a target.
You either will not see the target, or eat an anti-radar missile, or both.
So, the surveillance radars have gone to lower frequencies both L-Band and VHF, and a lot more computer processing power has been devoted to finding a firing solution with less dwell time for the radars.
Obviously, there are a lot of assumptions made here by APA, so there is some uncertainty there, though Lockheed-Martin does not have a whole bunch of credibility as to their claims, which describe the aircraft as near-invisible with the capability to strike a target multiple times in a sortee.