Square spiral microstrip antennas for wireless applications

Optimizing spiral antenna performance with a conductive plane backing and choice of dielectric material

“…(8) and (10) to solve for ee, which may then be substituted back into Eq. (7). The process may be repeated, and will result in convergence within 0.1% after only a few iterations.…”

“…To see if comparable performance may be obtained with the use of a nonair dielectric, additional analyses were performed with the use of modified E,, d, and SL parameters. Equation (10) was used to find the spiral-arm-width to ground-plane separation ratio to be less than 1: (5), (7), and (lo), were used in a simple FORTRAN routine to iteratively compute the parameters for the equivalent antenna designs shown in Table 1.…”

Design of a corner-truncated square-spiral microstrip patch antenna in the 5-GHz band

“…The performance characteristics of the two designs were found to be nearly identical. In practice, however, the square-spiral antenna may be advantageous as compared with a circular Archimedean one in terms of simplicity of construction and more efficient utilization of a limited area for a mounting plane [2][3][4][5]. Moreover, the squarespiral antenna has wide impedance bandwidth.…”

“…The radiating patch is printed on a thin FR-4 substrate with thickness of 1.6 mm and relative permittivity of 4.4. The ground plane has a size of 30 ϫ 30 mm 2 . The width of the patch, the distance (X and Y) of the patch, the thickness of the airgap, and the position of the feeding point are changed in steps, with the bandwidth calculated at each step obtained and optimized until a good return-loss characteristic is achieved for the 5-GHz band.…”

“…Diversity experiments are described, for example, in [1][2][3]. The enhancement obtained by diversity techniques can be transformed into terms of channelcapacity improvement [4 -6].…”