Gijo,Augustin; Shynu, S V; Aanandan,C K; Mohanan, P; Vasudevan, K(Microwave and Optical Technology Letters, April 20, 2005)
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Abstract:
An innovative phaseshifterless, wideband, micrustrip
leaky-wave antenna with an electronically steerable dual-pencil-beam
pattern in the H-plane is presented. The log-periodic geometry of the
leaky slots of the antenna results in a wide bandwidth of 25.19%. The
Jan beam can he steered up to 14° over the wide resonating band of the
anteww. The beam is also steerable at a fixed frequency. by reactivelty
loading the slots and a maximum steering angle of about 14° is ohserved.
for different capacitor values with an improved bandwidth of
33 _i%. This concept is studied using passive components but it can be extended to varactors
This 'study' deals with a preliminary study of automatic beam
steering properly in conducting polyaniline . Polyaniline in its undoped and
doped .state was prepared from aniline by the chemical oxidative polymerization
method. Dielectric properties of the samples were studied at S-band
microwave frequencies using cavity perturbation technique. It is found that
undoped po/vanihne is having greater dielectric loss and conductivity contpared
with the doped samples. The beam steering property is studied using
a perspex rod antenna and HP 85/OC vector network analyzer. The shift in
the radiated beam is studied for different do voltages. The results show that
polyaniline is a good nutterial far beam steering applications.