Smart Antenna using Switched Multibeam Array Ms
This paper describes the design and realization of a 44 Butler Matrix as a beam forming network along with 4 linear antenna arrays to obtain four steerable beams, operating at 2.4 GHz. The simulation results are obtained using HFSS software. Further the concept of multibeam switching is discussed with an idea of suspended feed in between two matrices.
An experimental investigation of electrically thick rectangular microstrip antennas
The electromagnetic properties of electrically thick rectangular microstrip antennas were investigated experimentally. Antennas were fabricated with different patch sizes and with electrical thicknesses ranging from 0.03 to 0.23 wavelengths in the dielectric substrate. The resonant frequencies were measured and compared to existing formulas. The bandwidth was calculated as a function of electrical thickness and the antenna radiation patterns were measured.
Broadband branchline coupler for S-band
The design of an S-band, broadband, microstrip 3 dB, 90 degrees branchline coupler is described and measured results for a prototype version are given. The design uses broadbanding stubs and three branches, with the central branch split into two of twice the characteristic impedance and separated by half wavelength transmission lines. This is a new technique to improve the bandwidth of which a theoretical account was given by Mayer (see ibid., vol.26, no.18, p.1477-8, 1990). Measured results for the prototype coupler show return loss greater than 17 dB and isolation greater than 16.5 dB, over a percentage bandwidth of 45%. >