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:warning: ANTENNA :warning: - Coggle Diagram
:warning: ANTENNA :warning:
WHAT IS ANTENNA :question:
:pencil2: Antenna is an electrical device that converts electrical currents into radio waves.
There are two way of trasmission :lock:
Transmitting antenna :arrow_forward: to efficiently radiate electromegnagnetic radiation in a preferred direction
Receiving antenna :arrow_forward: to efficiently receive elekctromagnetic radiation
Basic Structure :red_flag:
:one: antenna consists of metallic conductors and electrically connected to receiver or transmitter.
:two: the oscillating current passing through the antenna will cause the magnetic field to oscillate as well as the electron charge will also create a oscillating electric field
:three: the field will radiate from the antenna to the space as a
moving electromagnetic field wave.
:four: During reception, oscillating electric and magnetic fields of an incoming radio wave exert force on the electrons in the antenna elements,causing them to move back and forth, creating oscillating currents in the antenna
FUNCTION OF ANTENNA :check:
:check: the function of the antenna is to attach the electrical connection to the electromagnetic field required by the radial receiver or transmitter.
:check: Radio waves are electromagnetic waves which carry signals through the air (or through space) at the speed of light with almost no transmission loss.
:check: used directly for measurements in technologies including radar and gps
:check: used in systems such as radio and television broadcasting, point to point radio communication and wireless LAN
:black_flag: TYPES OF ANTENNA
:black_flag: Omnidirectional
:black_flag: Directional
:red_flag: Resonant antennas
:red_flag: non-resonant antennas
:!!: RADIATION PATTERN
radiation pattern is the variation of the power radiated by an antenna as a function of the direction away from the antenna and this power variation to arrival angle is observed in the antenna's far field.
:no_entry: ANTENNA GAIN
:no_entry: High-gain antenn that have advantage of longer range and better signal qualitq but high gain antenna must be aimed carefully in a particular direction.
:no_entry: Low-gain antennas have shorter range, but the orientation of the antenna is
relatively inconsequential.
:star: ANTENNA FAMILY
:star: END-FIRES - yagi-udas
:star: DIPOLES - Folded dipoles
:star: APERTURES - reflectors and parabolic