Subelement C: Receiving Systems – 10 Key Topics – 10 Exam Questions – 4 Drawings— Topic 28: Miscellaneous
Question 8-28C6
Element 8 (RADAR)When the receiver employs an MTI circuit:
Explanation
An MTI (Moving Target Indicator) circuit in a radar receiver is designed to filter out stationary echoes, known as clutter, by utilizing the Doppler effect. Moving targets cause a frequency (or phase) shift in the reflected radar signal, while stationary objects do not. The MTI circuit compares successive echoes and only processes signals that show this phase shift. This effectively removes returns from fixed objects like terrain, buildings, or weather, allowing only targets that are in motion relative to the radar to be displayed. Therefore, the primary function of an MTI circuit is to ensure that only moving targets are visible on the display.
Options A and C are incorrect because MTI is not related to receiver gain control or the disabling of AGC circuits; its function is target discrimination. Option D is incorrect as "rabbits" typically refer to spurious echoes or interference, and MTI's purpose is to *remove* ground clutter itself, not to make clutter free of "rabbits."
Related Questions
8-28C4 The condition known as “glint” refers to a shifting of clutter with each RADAR pulse and can be caused by a:8-28C5 An ion discharge (TR) cell is used to:8-29D1 Modern liquid crystal displays have a pixel count of:8-29D2 Voltages used in CRT anode circuits are in what range of value?8-29D3 The purpose of the aquadag coating on the CRT is: