• The basic elements required for
the transmission and reception of a signal through long distance using
electromagnetic waves are transducer, amplifier, carrier signal, modulator,
power amplifier, medium of transmission, transmitting and receiving antenna,
• For long-distance
transmission, the baseband signal is modulated with the carrier wave.
• If the
amplitude of the carrier signal is modified with the instantaneous amplitude of
the baseband signal then it is called amplitude modulation.
frequency of the carrier signal is modified with the instantaneous amplitude of
the baseband signal in frequency modulation.
instantaneous amplitude of the baseband signal modifies the phase of the
carrier signal keeping the amplitude and frequency constant is called phase
• The height of the transmitting and
receiving antenna must be a multiple of λ/4.
• If the EM
waves transmitted by the transmitter glide over the surface of the earth to
reach the receiver, then the propagation of EM waves is called ground wave
waves radiated from an antenna, directed upwards at large angles gets reflected
by the ionosphere back to earth is called sky wave propagation.
process of sending and receiving information signal through space is called
space wave communication.
satellite communication is a mode of communication of signal between
transmitter and receiver via satellite.
• Fiber-optic communication is a
method of transmitting information by sending pulses of light through an
• Radar basically stands for Radio Detection and Ranging System.
It is one of the important applications of communication systems for remote
• Mobile Communication is used to communicate with others in
different locations without the use of any physical connection like wires or
• GPS stands for Global Positioning System that offers
geolocation and time.
• Communication technology is used
extensively in sectors like fisheries, mining, and agriculture.