Reconfigurable Antenna (Circular Micro strip Patch Antenna) Using Varactor Diodes

Main Article Content

Pawan Pujari
Kirti Vyas, Bhoopendra Kumar Sharma


An antenna that possesses the ability to modify its characteristics, such as operating frequency, polarization or radiation pattern,
in real time condition is referred to as a reconfigurable antenna. Reconfigurable antennae have the potential to add substantial degrees of
freedom and functionality to communication and phase array systems. Reconfigurable antennae can be simply used to reduce the number of
antennae necessary for intended system function, but they can also be designed to serve much more complex roles[1]. In addition,
reconfigurable antennae can be a cheaper alternative to traditional adaptive arrays or they can be incorporated into adaptive arrays to
improve their performance by providing additional degrees of freedom. Reconfigurability in antennae allows us for spectrum reallocation in
multi-band communication systems, dynamic spectrum management, reduces the number and size of antennae in a system. Generally
reconfigurability can be obtained using following techniques: Tunable elements in the feeding networks, adaptive matching networks,
phase shifters and tunable filters, tunable elements embedded such as PIN diodes, MEMS (switches, varactors, moveable parts) and optical
switching in the radiating elements, mechanically moveable radiating elements [2].
The proposed reconfigurable Circular Patch antenna is a good candidate for X band communication. Circular Patch Antenna designed,
simulated at 8.5 GHz successfully. The same antenna was made capable for frequency tuning by using varactor diode at optimized position
and achieved from 6.5GHz to 8.2GHz in simulation and 7.6GHz to 8.6GHz and 10.4 to 11.6 GHz in practical. Three varactor diodes were
used at optimized positions only for making the antenna tunable at different resonant frequencies without changing any other parameter and
preventing the mode splitting [10]. The E-plane radiation pattern of designed antenna was found 220 offset with maximum power 6.4 dB.
The Half Power Beam width was found 1060. In this radiation pattern there were two side lobes and one back lobe which was came out
18.8 dB down from the one major lobe. The H-plane radiation pattern was found 00 offset with maximum power -6.2 dB and the half power
beam width for this pattern was found 65.30.

Keywords: Micro strip antenna, s-parameter (S11), gain, radiation patterns.


Download data is not yet available.

Article Details