HORN ANTENNA What is Horn Antenna ? A horn antenna is an antenna that consistsof a flaring metal waveguide shaped likea horn to direct radio waves in a beam.
Horn Antenna as termination ofwaveguideWaveguide terminated with horn antennaradiates effectively than open endedrectangular waveguide.Open endedrectangular waveguideHorn Antenna as terminationof waveguide
HORN ANTENNA A horn antenna is used to transmit radiowaves from a waveguide (a metal pipe usedto carry radio waves) out into space, or collectradio waves into a waveguide for reception Horns are widely used as antennasat UHF and microwave frequencies, above300 MHz.
Types of Horn AntennaPyramidal horn – a horn antenna with thehorn in the shape of a four-sided pyramid,with a rectangular cross section.They are acommon type, used with rectangularwaveguides, and radiate linearly polarizedradio wavessectoral horn – A pyramidal horn with onlyone pair of sides flared and the other pairparallel.Which is narrow in the plane of theflared sides, but wide in the plane of thenarrow sidesE-pane horn (b) – A sectoral horn flared in thedirection of the electric or E-field in the waveguide.H-plane horn (c) – A sectoral horn flared in thedirection of the magnetic or H-field in the waveguide.Conical horn (d)Exponential horn
Horn Antenna Why it is use ? It has high antenna gain, which can range upto 25 dB in some cases, with 10-20 dB beingtypical. It is used as feeders ( feed horns) for largerantenna structures such as parabolicantennas. And as directive antennas for such devicesas radar guns, and microwave radiometers.
SLOT ANTENNA A slot antenna consists of a metal surface,usually a flat plate, with a hole or slot cut out. Slot antennas are used typically atfrequencies between 300 MHz and 24 GHz. the slot radiates electromagnetic waves insimilar way to a dipole antenna.
SLOT ANTENNA Consider an infinite conducting sheet, with arectangular slot cut out of dimensions a and b, asshown in Figure. If we can excite some reasonable fields in the slot(often called the aperture), we have a slot antenna.
SLOT ANTENNA Applications Slot antennas are widely usedin radar antennas In sector antennas used for cell phone basestations. A slot antennas main advantages are its size,design simplicity
PATCH OR MICROSTRIP ANTENNA A patch antenna (also known as a microstripantenna) is a type of radio antenna , whichcan be mounted on a flat surface. It consists of a flat rectangular sheet or"patch" of metal, mounted over a larger sheetof metal called a ground plane.
MICROSTRIP OR PATCH ANTENNA Microstrip or patch antennas are becomingincreasingly useful because they can beprinted directly onto a circuit board. Microstrip antennas are becoming verywidespread within the mobile phone market.Patch antennas are low cost, and are easilyfabricated
MicroStrip OR Patch AntennaTopView of Patch Antenna Side view of Patch Antenna
Quad Helix Antenna ForTelemtry A Quad helix Antenna is simply type ofhelix(often called helical) antenna. In this four helix antennas are built toghetheron a conducting material. There are two modes in which helicalantennas operate Normal mode and Axial mode.
Quad Helix Antenna ForTelemtry In normal mode the dimension of helix lessthan wavelength. In Axial mode the dimension of helix iscomparable to wavelength. These helix antennas are referred to as axial-mode helical antennas. They are used to send and recieve themeasurements from a remote area.
TheseAntennas work on high frequenciesranging fromVHF up to microwave. The antenna produces radio waveswith circular polarisation.circular polarisation
Notch Antenna NotchAntenna is created from the slotantenna when slot antenna is cut down fromthe middle then it works as slot antenna. Microwave antenna in which the radiationpattern is determined by the size and shapeof a notch or slot in a radiating surface.