The radars involved in ABM early warning and threat tracking cover a fair range of the spectrum. In general terms the early-warning in done at the lower frequencies, and threat tracking at the higher.

For example:

Pave Paws – UHF band (0.3 to 1 GHz)
Cobra Dane – reported to be L band (1 – 2 GHz)
Green Pine – L-Band (1 – 2 GHz)
Aegis AN/SPY-1 – S-band (2 to 4 GHz)
GBR-P – X-band (7 – 12.5 GHz)
THAAD – X-band (7 – 12.5 GHz)

Mercurius, your post was very informative and interesting. As per the above data, the Indian BMD system uses 1-2 Ghz range, as its ground radar is the Israeli Green Pine radar (also known as Swordfish). The targets can be intercepted at an altitude of 50-80 kms. Thus, by this confirmed frequency-altitude information, may get a rough estimate as to how much frequency range may be required to intercept at a given altitude.

An RV is a fairly difficult environment in which to implement RCS-reduction technologies. An RV must be designed primarily not only to withstand the effects of re-entry, but to have the minimum of trajectory perturbations during re-entry. Ideally, stealth measures would have to be effective from VHF to X-band, but this range could be narrowed by concentrating on the frequencies where they would prove most disruptive to the defensive systems of the target nation. They could also pose a penalty by taking up a portion of the missile’s throw weight.

The Indian BMD system uses not only the ground radar, but also collates information from ground radar, and other mesh of sensors. All this data together is subject to computation, and the incoming target’s path is predicted. This data is fed to the interceptor to orient its path appropriately and used to home onto the target missile.

BTW – Japan conducted its first SM-3 engagement of ballistic-missile target yesterday. The firing was from the Japanese destroyer KONGO (DDG-173).

The news report for the above is here. It was actually a joint effort between the US and Japan.

Earlier I stated that M-9 and M-11 missiles may be countered by this system. As per Dr. Saraswat, exactly these 2 kinds of missiles were simulated in the tests of the BMD, which and I quote him, “are with our adversaries”. In another interview he stated that this system can target missiles having ranges upto 2000 kms. Thus, all missiles in the Pakistani arsenal will be rendered ineffective by this system.

References :-

1) http://www.hindu.com/2007/12/07/stories/2007120761241800.htm

The following is an impression of the working of the Prithvi Air Defence* :-

sferrin and sealordlawrence, whatever be the case, atleast some rudimentary defence is preferable than absolutely none at all. Even then, citizens in Pakistan, Iran, N. Korea whose governments have taken very offensive stances, are not at an increased risk, because the BMDs of India, Israel and S. Korea are in keeping with the commitment of declared No-First-Use policy of these nations.

Hence India for example, is likely to fire ballistic missiles with conventional warheads at will, but nuclear ones will not be fired unless a Pakistani or Chinese nucler tipped ballistic missile, evades the BMD defence and does damage.

* rudranath, from bharat rakshak board

PAC-3 is only 1 part of american BMD and very limited. THAAD will form the second one.

broncho, I agree as the THAAD will form the layer at 150 kms above the surface, whereas the PAC-3 will be used to intercept missiles in the 45 km range.
However, both are separate systems, use different ground radars and use overall different missiles and tracking technology.

The Indian BMD however, has combined the endo and exo modes that can be countered by the same type missile, using the same ground radar and tracking.

The following are excerpts from an interview by Dr. Saraswat, head of DRDO :-

Q. Please describe the homegrown ballistic missile defense system. How many missiles will it have for different layers of threats?
A. Our missile configuration is a three-layered missile defense configuration. We are planning to engage ballistic missiles at the exo-atmospheric layer, i.e., the layer where it enters the atmosphere, and the endo-atmospheric layer, where there is a thermally sensitive atmospheric layer. This configuration gives us the best probability of killing a ballistic missile coming to us. To increase hit probability, we can plan to launch two to three missiles each for exo- and endo-atmospheric.

The missile that demonstrates our capability to intercept ballistic missiles at exo-atmospheric altitudes is called PAD. It is a two-stage missile. The first stage is liquid, and the second is a solid rocket motor with many additional features, which are leading to an interception or engaging the ballistic missiles. For example, it has seeker guidance, divert thruster which can generate a lateral acceleration at more than 5 Gs at 50 kilometers altitude.

Q. What is the speed of the air defense missile?
A. It is between 4.5 and 5 Mach. The same system has the capability to engage 300-kilometer to 2,000-kilometer classes of ballistic missiles.

Q. What is Phase II?
A. The same missile interceptors cannot cover all threats. Threat targets of longer ranges — 2,000 kilometers — will make our phase-II development.

During Phase I: Endo-atmospheric interceptor is AAD. This interceptor will engage targets at 25 kilometers. AAD is superior in terms of coverage area compared to PAC-3, which is 15 kilometers. You can see the difference. AAD’s equivalent is the Israeli Arrow, which intercepts at 40 kilometers. PAD is 50 to 80 kilometers. America is building a missile, THAAD — Terminal High Altitude Area Defense — that intercepts out to 120 kilometers, but it is still in development. However, a lot of failures have taken place during THAAD development.

Reference :-
http://www.defensenews.com/aero/story.php?id=2524130

That is completely incorrect. How many interceptors will India have compared to its potential opponents warheads, how effective will they be against increasingly effective and sophisticated warheads and counter-measures. One also has to consider the security of the ABM system to other forms of strategic attack, such as speed long range cruise missiles. As for this system being 99% effective………….very unlikely if not impossible.

sealordlawrence, to counter only Chinese threat, 200 such exo-endo missile pairs may have to be developed. Presently, most ballistic missiles do not have an ECM facility and China and Pakistan are not known to possess MIRV missiles. Thus, the BMD will be effective for the long-term.
Regarding cruise missiles, they can be countered by the Barak in India’s inventory and possibly Akash. As per Dr. Saraswat’s statement, the BMD system will also be designed counter cruise missiles.

In the 90s the Marines had modified Hawk to do the job even better. Still though, it’s a start. It is amusing though to hear people go on about how Pakistan needs to worry because India now has missile defenses, but at the same time the US’s is ineffective. 😉

sferrin, as per the head of DRDO, Dr. Saraswat, the Pradyumna BMD missile has slightly better performance than the Patriot PAC-3 :

The AAD-02 was slightly better than the PAC-3 (Patriot Advanced Capability) of the U.S. in terms of range and altitude. The direct hit compared very well with the PAC-3 in terms of accuracy.

Avinash Chander, Director, Advanced Systems’ Laboratory (ASL), Hyderabad, said, “I don’t think any country [other than India] was able to achieve a direct-hit in the first attempt” in endo-atmosphere.

Reference :-

http://www.hindu.com/2007/12/07/stories/2007120761241800.htm

There is nothing in the LCA design that would suggest it being superior to the Gripen. The Gripen obviously has a more slender fuselage, if it offers lower drag compared to the fuselage of the Tejas, I don’t know. However, the Gripens main wing in conjunction with its fully movable canards allows for an optimal L/D ratio for all cg positions, Mach and AoA. A luxury the Tejas doesn’t have.

As we have discussed earlier, the slenderness of Gripen’s fuselage is negated by its wide-angle wings and much more by its canards, which generate severe drag (profile and induced). Tejas does not have canards and so avoids that much drag, but yet generates a vortex above its wings by having cranks on its wings. Thus it is a unique design.

It has not been proven that canards provide optimal L/D ratio. They are a European adaptation only; all frontline US and Russian jets have avoided canards throughout all generations.

Gripens inlet design also allows for a lower drag compared to the Tejas. The SAAB 105 at first had “armpit” located intakes similar to the Tejas, but they eventually changed it in order to lower the drag, and to get a better airflow to the engine.

Tejas’ almost double wingspan in comparison to the Gripen, may make up for the loss of airflow due to its intakes.

Really? Highest, in what way? The lower fuselage doesn’t blend with the wing at all.

The Tejas actually does have one of the highest wing-body blends in the world. As may be seen from the schematic, it has been more fused with the fuselage compared to other fighter jets.

It’s not blended. The vertical fin is placed on top of the spine. The F-8 Crusader and F-5A Freedom Fighter for example had their vertical fins blended with the spine. The F-9 Panther had its fin blended with the fuselage though.

The above is true. Earlier, I had incorrectly mentioned as fuselage blending, whereas the tail-fin is the first globally to be a monolithic honeycomb piece.

I’m not so sure that angle proves it has any bottleshape to it. It looks like blending between the wing and body at the wingroot. Perhaps the cross-sectional area of the Tejas’s body is distributed effectively, but from that photo one cannot honestly say that is the case.

Actually, Tejas also has the record of having one of the highest wing-body blends in the world. It is the only fighter to have a blended vertical-fin with the fuselage. It has one of the lowest part counts also, on account of composites and modularity (only 7000 individual parts are present in Tejas TD-1).

Besides this, it is said to the only cranked, cropped and double-delta combat jet. Thus, it is clear that the Tejas has incorporated many meticulously planned design features.

Just looking at how the air will flow across the plane’s shape in the line art leads me to suspect that supersonic drag is more of a problem than raw power of the engine. It should have power to spare at this point in the program. Convair had a very streamlined design that couldn’t get supersonic when smarter shaping allowed it to boost the speed by 25% with a modest 7% boost in thrust even though it weighed two additional tons by the end of the change. Guess what, that plane was seventy feet long, 700 square feet of wing, and weighed 15 tons when loaded yet did that stunt on less power than what the Tejas uses.

Tejas’ body is also streamlined as is evident from the line drawings. Tejas also has an unstable design, that ensures stability by the shifting of the CG at the crossing of the sound barrier. Its Flight control system keeps the plane optimally stable by using the forward slats and other movable parts, while simultaneously keeping the pilot commands “in the reckoning” too.

Thus, it may be unclear as to how the IAF finds the Tejas “underpowered” (note that there are no aerodynamic problems). It may be so that the Tejas has reached only 1.4-1.5 mach in testing so far, and hence the IAF may have commented on that aspect, which the media may have misinterpreted as a general criticism.