Chapter 15, Doppler Navigation

Question 1

Doppler navigation systems operate in which
frequency range?

Answer 1

SHF

Question 2

When moving towards a sound source, what
effect will Doppler shift have on the pitch of
the sound as heard by an observer?

Answer 2

Increased pitch

Question 3

What effect does increasing the frequency of a transmitted Doppler beam have on sensitivity
of the frequency shift?

Answer 3

Increased

Question 4

Raw Doppler calculations include

Answer 4

Ground speed and drift

Question 5

Velocity and position outputs from a Doppler
navigation system are provided

Answer 5

On a continuous basis

Question 6

The backscattering features of the terrain
affect the Doppler navigation system’s

Answer 6

Signal-to-noise ratio

Question 7

Integrating Doppler ground speed calculations
will provide

Answer 7

Distance travelled

Question 8

Drift can be measured by directing a beam

Answer 8

At right angles to the direction of travel

Question 9

Doppler position calculations degrade with

Answer 9

Distance travelled

Question 10

When hovering directly over an object in the
sea with a six-knot tide, the Doppler system
will indicate

Answer 10

Zero drift

Question 11

When hovering over water, the ‘worst case’
conditions for signal-to-noise ratios are with

Answer 11

Smooth sea conditions

Question 12

Doppler system beams in the lambda arrangement have beams directed in the following way

Answer 12

Forward, aft and to one side of the aircraft

Question 13

Backscattering of a Doppler beam from the
surface of water is

Answer 13

Low from a smooth surface