Question

What is a square law device and a bandpass filter, and write the frequency range of satellite communication. 😁

Answer 1

(1) A square law device is one that produces an output voltage or current that is proportional to the square of its input voltage or current. Square law devices are mainly used in modulators and detectors. Example: The detector diode used in communication systems, FETs used in balanced modulator etc.

(2) The band pass filter used in the modulator is centered at the frequency of the carrier wave.


Satellite communication is an example of the broadcast mode ofcommunication. (ii) Space wave mode of propagation: In the frequency range 30 MHz to 1000 Mhz, the wavelengths are in the range of 30 cm to 10 m. So frequency range of 5.925 - 6.425 GHz is used in satellite communication.