Spread Spectrum (SS) encoding: a) Name four spread spectrum techniques. b) Which one of them was originally devised against eavesdropping in the military environment?

(a)

The four types of spread spectrum techniques are as follows -

1. Direct sequence spread spectrum.

2. frequency hopping spread spectrum.

3. chirp spread spectrum.

4. time hopping spread spectrum.

(b)

The Direct sequence spread spectrum was devised for eavesdropping in the military.

In the field of telecommunications, the Direct sequence spread spectrum, it is the technique of spread spectrum modulation which is used to reduce the overall inference of the signal.