Subelement A: RADAR Principles – 10 Key Topics – 10 Exam Questions – 8 Drawings— Topic 4: Power, Pulse Width, PRR
Question 8-4A1
Element 8 (RADAR)A pulse RADAR has a pulse repetition frequency (PRF) of 400 Hz, a pulse width of 1 microsecond, and a peak power of 100 kilowatts. The average power of the RADAR transmitter is:
Explanation
The average power of a pulsed RADAR transmitter is determined by its peak power and duty cycle. The duty cycle represents the fraction of time the transmitter is actually emitting a pulse.
The duty cycle (D) is calculated as:
D = Pulse Width (τ) × Pulse Repetition Frequency (PRF)
Given:
Pulse Width (τ) = 1 microsecond = 1 × 10⁻⁶ seconds
PRF = 400 Hz
Duty Cycle = (1 × 10⁻⁶ s) × (400 Hz) = 0.0004
The average power (P_avg) is then:
P_avg = Peak Power (P_peak) × Duty Cycle
Given:
Peak Power (P_peak) = 100 kilowatts = 100,000 watts
P_avg = 100,000 W × 0.0004 = 40 watts.
Therefore, the average power of the RADAR transmitter is 40 watts. Options A, C, and D result from incorrect application of the formula or mathematical errors.
Related Questions
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