...capable of detecting a 0.1 m^2 target at 250 km or a 0.4 m^2 target at 280 km, which works out to a detection range (for a 1 m^2 target) of 450 km.
This is a general FYI to the readers on how these things are spec-ed out.
When a customer goes shopping for a radar system, be it for civilian air traffic control or military combat usage, the customer will say something like:
'I want a radar that will have a 90% probability of detection of a 5 m/square target at 200 km distance.'
Here is where it gets tricky...
It does not mean a body have a fixed radar cross section (RCS) of 5 m2. It mean a body -- any body -- become or develops an RCS value of 5 m2. When a customer specified a probability figure, an estimated RCS value, and a distance, he has good reasons for it.
1) If the vendor can meet the 5 m2 at 200 km distance requirements but only at 80% probability, the proposed system failed to meet specs.
2) If the vendor can meet the 5 m2 at 90% probability requirements but only at 190 km distance, the proposed system failed to meet specs.
3) If the vendor can meet the 5 m2 at 90% probability requirements but at 210 km distance, the proposed system exceeded specs.
Keep in mind that a body's radar cross section (RCS) is a fictitious value. The word 'fictitious' here does not mean it is made up. In a sense, it is made up, but in the technical sense, it mean the RCS value is a real value but also is a variable, or fluctuating, that is highly influenced by many external factors, and that is why there is a percentage of probability, or guess, that something have A or B or C cross section value.
For vendor 1, the proposed system set the distance as highest priority and widened the acceptable variability of probability that the target is (somewhere around) 5 m2. The vendor is perfectly free to do this.
For vendor 2, the proposed system set probability as highest priority, meaning that if the target is estimated to be 5 m2, under lab and field verification, the system has 90% probability of that estimation. Unfortunately, the target had to be 10 km closer to the radar in order to achieve that 90% probability estimation. The civilian customer may say that 10 km closer mean increased odds of mid-air collisions in a high traffic environment and refuse to buy. The military customer may say that 10 km closer mean the enemy can destroy a vital asset and refuse to buy.
For vendor 3, the proposed system may have superior technology than his competitors in terms of hardware and software so that no matter what priority was used, either distance out or probability of RCS, the superior technology compensated.
If the target is a B-52, this target may become 5 m2 with 90% probability at 400 km distance out for vendors 1 and 2, and at 500 km distance out for vendor 3.
If the target is a B-2, this target may become 5 m2 with 90% probability at 10 km distance out for vendor 1, at 5 km distance out for vendor 2, and 20 km distance out for vendor 3.
The customer can spec-ed the system at 1 m2 with 99% probability at 300 km distance out and all three vendors would fail to meet specs. The customer has to know, not just the current technology level but the level that is available to the vendors, before he make his specs. If a potential adversary have superior technology, he cannot make his specs based upon technology that is not available the vendors in his country. Obviously, he cannot go to this potential adversary and ask if their vendors make radars for him.
So take these public figures of what radar systems can do what at so-and-so distance with suspicion. Also understand that just because a radar system have XYZ specs, that does not mean it is a peer with other systems. The figures sounds impressive stand alone, but they may pales in comparisons to other systems from other countries precisely because the vendor do not have peer technologies.
Last post before this is 2010...
