CMRT Signal Processing & Antenna Theory 5

Question 1

In marine radar, rain clutter differs from sea clutter primarily because:

Accepted Answer

Rain clutter is volumetric and can appear at any range within precipitation areas

Answer

Rain clutter is volumetric, occurring wherever precipitation exists, unlike sea clutter which is surface-based and range-dependent.

Question 2

What is the significance of the radar ambiguity function?

Accepted Answer

It describes a waveform's joint range and Doppler resolution and ambiguity performance

Answer

The ambiguity function characterizes how well a radar waveform can simultaneously resolve targets in range and Doppler velocity.

Question 3

Which waveguide mode is the dominant mode used in rectangular waveguides for marine radar feeds?

Accepted Answer

TE10

Answer

The TE10 mode is the dominant mode in rectangular waveguides because it has the lowest cutoff frequency and propagates with the least loss.

Question 4

A radar system has a false alarm time of 10 minutes. If the detection threshold is lowered, the false alarm time will:

Accepted Answer

Decrease, producing more false alarms per unit time

Answer

Lowering the detection threshold allows more noise peaks to exceed it, increasing the false alarm rate and decreasing the mean time between false alarms.

Question 5

What is the function of a circulator in a marine radar transceiver?

Accepted Answer

It routes the transmit pulse to the antenna and the receive echo to the receiver

Answer

A circulator is a non-reciprocal device that directs transmit energy to the antenna and receive energy from the antenna to the receiver, protecting the receiver from transmit power.

(CMRT) Certified Marine Radar Technician Practice Test

(CMRT) Certified Marine Radar Technician Practice Test

CMRT Signal Processing & Antenna Theory 5