Which of the following is false with respect to PESA?

PESA is more technically simple

PESA can only have one main beam and one transmit power source

Because it uses a, multiple frequencies, it is less susceptible to enemy jammers

All elements combine to a single receiver. Each element steers the beam through phase shifters

Correct Answer : Because it uses a, multiple frequencies, it is less susceptible to enemy jammers

Explanation : In a PESA only one transmitter drives the whole antenna and hence only one frequency can be achieved at a time. This allows it to be more susceptible to jammers.

Recently Updated in Avionics Questions

What is the range of typical weather radar?

5 nmi

50 nmi

200 nmi

500 nmi

Correct Answer : Option (C) : 200 nmi

Explanation : The use of airborne weather radar is one method of storm avoidance. A weather radar system can show centers at a distance of up to 200 nmi.

What is the frequency of operation of weather radar?

500 kHz

548 kHz

1000 MHz

9375 MHz

Correct Answer : Option (D) : 9375 MHz

Explanation : The weather radar operates at a frequency of 9375 MHz, corresponding to a wavelength of 3 cm. This small wavelength gets easily reflected from clouds containing high water concentrations.

What is the gain required by a weather radar antenna?

5 dB

25 dB

50 dB

65 dB

Correct Answer : Option (B) : 25 dB

Explanation : The signal strength of echoes from storms located at a distance from the aircraft is very low, which requires the transmitter to operate at very high power levels and that the antenna have a gain of more than 25 dB.