SerbNationalist wrote:Tell me Garry, is Buk equipped with an AESA radar, or if it isn't, can it be equipped? And by Buk I mean do TELARS have it, I know that it can be used as a surveillance radar! And tell me what is the difference between PESA and AESA, which is better? Sorry for the question but trying to learn that stuff, am really interested in it.
mind if i tag along
related to Buk.. well Buk-M1 is likely equipped with typical Slotted Planar Array RADAR, not PESA or AESA, only BUK-M2 equipped with PESA Engagement RADAR .
and yes every BUK Launcher have Engagement RADAR's on its own.
Related to PESA or AESA , the primary differences between them is their power source , PESA RADAR uses Single transmitter to transmit their beam , their Antenna elements contains no "Active" elements, only Phase Shifters for their electronic Scanning .
Example is Irbis-E RADAR which uses 2 Travelling Wave Tube to form its transmitter system, it's antenna contains nothing but a beam steering controller and phase shifters .
as for AESA every antenna elements mounted on it have their own transmitter in shape of MMIC (Monolithic Microwave Integrated Circuit) along with power amplifier , thus every element can transmit power by itself , and those devices are mounted in the Antenna (PESA transmitter is NOT in the Antenna but in separate module/LRU) .
as for AESA Vs PESA comparison , the primary advantages held by AESA over PESA is in the Reliability of the transmitter, PESA transmitter (Travelling Wave Tube, Klystrons, Magnetrons ) are usually "short lived" due to the fact that they often handle very high amount of Microwave power in often very confined or small space, like say fighter RADAR's , their MTBF (mean Time Between Failure) is somewhere between 200-300 Hrs , and can be as low as 5 hours (early Su-27's N001 Myech RADAR's) once the transmitter fail , the entire RADAR will cease to function .
AESA RADAR in other hand , since MMIC modules handle lower power (5 watts till some 100 watts) their reliability is higher , APG-79 MMIC T/R Modules may last with MTBF up to some 20.000 Hours , another advantage is since each modules have its own transmitter, failure of some modules may not hamper the RADAR's performance, however there is a "safe limit" of 10% .. more than it entire RADAR's may fail .
as for PESA type RADAR, the primary advantages over AESA is price .. AESA is EXPENSIVE.. cost of the AESA can up to millions of $ , primarily determined by emitted power and numbers of transmit and receive modules .
You can try calculate it using following equation, for generalized phased Array system (AESA or PESA) :
Ch=Cost of Hardware ($)
Ct=Cost of Transmitter module
Nt=Number of Transmitters
Pav=Average emitted power (PPeak*Duty Cycle)
Cr=Cost of Receiver Module
Nr= Number of Receivers
Cpav=Cost of producing average power (U$/watt)
Let's have an example.. now we have AESA RADAR with 2000 T/R Modules with peak power of 20 Kilowatts and duty cycle of typical Russian fighter jets (25%), cost of the T/R modules is U$ 500
In the other hand we have a PESA RADAR with single transmitter having 2 Travelling wave tube each delivering 10Kw of power thus Peak power of the RADAR's is 20Kw .. cost of the transmitter is U$ 250.000 , the PESA have 2000 receive module with cost of U$ 300 each .
duty cycle is same .
cost of producing average power for both RADAR is assumed to be the same U$ 0,1/watt
so which one is cheaper ?
Pav= 20.000 watt* 0.25 = 5000 Watt
Cost of AESA : U$ 3.000.000
Pav= same as above (5000 watts)
Cost of PESA : U$ 850.500
the PESA RADAR with same power and same duty cycle comes in much cheaper .
perhaps that is why SAM engagement RADAR's which may consist of some 10.000 antenna modules uses PESA scheme instead AESA.