Jhon Smith
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Pakistan DefenceVerified account@defencepk
#Pakistan Air Force intends to upgrade all JF-17 Thunder fighters with advanced AESA radars including older blocks.
facebook]1116808918373907
ASEA Radar will be mistake of PAF, they should stay with mechanical one in preference of radar based on solid state tec (particularly AESA )!
The entire idea to replace Jf-17 radar just as similiar one to Eurofightr or US f-16 block-52 jet radars will be lapse at PAF scientific devision part!!
IN REPLY TO THAT THREAD (https://defence.pk/threads/here-is-jf-17-block-iiis-aesa-radar-klj-7a.458854/)
AESA RADAR IS 70% LESS POWERFULL THAN PESA RADAR ON SPLIT WAVE
A passive electronically scanned array (PESA), also known as passive phased array, is a phased array radar which has a single central radio frequency source (such as a magnetron, a klystron or a travelling wave tube), sending energy into the multiple phase shift modules, which then send energy into the individual emitting elements in the front of the antenna. This contrasts with active electronically scanned array (AESA) devices, which have a separate radio frequency source for each phase shifter/emitting element. A PESA radar is therefore simpler to construct than an AESA.
AESA does have the ability to form multiple beams at different frequencies at the same time, but this is less common. If you are splitting up your beam into a beam for Freq-A and a beam for Freq-B, then each beam is now half as powerful and will get you (1/2)^1/4=84" position: relative of the range you would get if you were using the full array. Divide that into 4 sub-beams and now you’re down to 70% of your maximum range. You also lose monopulse processing which allows you to fine tune your angle measurement. Without monopulse, your angle measurement is only going to be as accurate as your beam width, and now with only half of an array, your beam just got wider. You typically don’t need this feature where you do two frequencies at the same time, because the radars are pulsed. Radars are emitting thousands of pulses per second. And after each dwell, you reset to a new target, re-steer the beam, and then send more pulses. Both AESA and PESA can track hundreds of targets at the same time.
Most phased array radars in the world are PESA. Microwave landing system uses PESA transmit-only arrays.
Radar systems generally work by connecting an antenna to a powerful radio transmitter to emit a short pulse of signal. The transmitter is then disconnected and the antenna is connected to a sensitive receiver which amplifies any echos from target objects. By measuring the time it takes for the signal to return, the radar receiver can determine the distance to the object. The receiver then sends the resulting output to a display of some sort.
The thought to convert Jf-17 radar as similiar to f-16 will be blunder of PAF scientists!
https://www.ll.mit.edu/publications/journal/pdf/vol12_no2/12_2devphasedarray.pdf
#Pakistan Air Force intends to upgrade all JF-17 Thunder fighters with advanced AESA radars including older blocks.
facebook]1116808918373907
ASEA Radar will be mistake of PAF, they should stay with mechanical one in preference of radar based on solid state tec (particularly AESA )!
The entire idea to replace Jf-17 radar just as similiar one to Eurofightr or US f-16 block-52 jet radars will be lapse at PAF scientific devision part!!
IN REPLY TO THAT THREAD (https://defence.pk/threads/here-is-jf-17-block-iiis-aesa-radar-klj-7a.458854/)
AESA RADAR IS 70% LESS POWERFULL THAN PESA RADAR ON SPLIT WAVE
A passive electronically scanned array (PESA), also known as passive phased array, is a phased array radar which has a single central radio frequency source (such as a magnetron, a klystron or a travelling wave tube), sending energy into the multiple phase shift modules, which then send energy into the individual emitting elements in the front of the antenna. This contrasts with active electronically scanned array (AESA) devices, which have a separate radio frequency source for each phase shifter/emitting element. A PESA radar is therefore simpler to construct than an AESA.
AESA does have the ability to form multiple beams at different frequencies at the same time, but this is less common. If you are splitting up your beam into a beam for Freq-A and a beam for Freq-B, then each beam is now half as powerful and will get you (1/2)^1/4=84" position: relative of the range you would get if you were using the full array. Divide that into 4 sub-beams and now you’re down to 70% of your maximum range. You also lose monopulse processing which allows you to fine tune your angle measurement. Without monopulse, your angle measurement is only going to be as accurate as your beam width, and now with only half of an array, your beam just got wider. You typically don’t need this feature where you do two frequencies at the same time, because the radars are pulsed. Radars are emitting thousands of pulses per second. And after each dwell, you reset to a new target, re-steer the beam, and then send more pulses. Both AESA and PESA can track hundreds of targets at the same time.
Most phased array radars in the world are PESA. Microwave landing system uses PESA transmit-only arrays.
Radar systems generally work by connecting an antenna to a powerful radio transmitter to emit a short pulse of signal. The transmitter is then disconnected and the antenna is connected to a sensitive receiver which amplifies any echos from target objects. By measuring the time it takes for the signal to return, the radar receiver can determine the distance to the object. The receiver then sends the resulting output to a display of some sort.
The thought to convert Jf-17 radar as similiar to f-16 will be blunder of PAF scientists!
https://www.ll.mit.edu/publications/journal/pdf/vol12_no2/12_2devphasedarray.pdf
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