Question

Which among the following is the function of out-of-band sensing?

(a) Detect primary base-station

(b) Detect spectrum holes

(c) Detect primary user

(d) Detect xG users

The question was asked in a national level competition.

My question is from Next Generation Wireless Network in section Next Generation Wireless Network of Cognitive Radio

Answer 1

Right choice is (b) Detect spectrum holes

The best I can explain: A cognitive radio should be aware of its surrounding radio environment. Spectrum sensing allows a radio to find the unused spectrum in the radio environment. In out-of-band sensing, cognitive radio users focus on the identification of spectrum holes over a wide frequency range to transmit their information.