A novel stacked patch antenna with dual band and diverse pattern characteristics

Abstract

A dual‐band patch antenna with diverse radiation patterns is presented in this paper. Circular patch and turnstile‐shaped patch are placed up and down to obtain dual band characteristic. Two surface current loops on the circular patch and turnstile‐shaped patch work like equivalent magnetic dipole. Four rectangle slots and four PIN diodes are loaded on the circular patch to readjust the surface current. Due to the changed current path, an equivalent electric dipole is introduced and two dipoles with phase difference of 180° are combined with each other to achieve directional radiation pattern. By switching the states of the diode to control the connection states of the rectangle slot on the circular patch, then a dual‐band antenna with diverse patterns is designed. The measured results show that the overlapping bandwidths of lower band f1 is 2.9% (2.42‐2.49 GHz) and over 2.9 dBi gain, the overlapping bandwidths of upper band f2 is 2.0% (4.87‐4.97 GHz) and over 4.8 dBi gain. The measured patterns of f1 show that the proposed antenna can not only omnidirectional radiation but also directional radiation with a scan angle of 90°. Meanwhile, the measured patterns of f2 remain omnidirectional radiation.

Low‐profile and broadband microstrip antenna with pattern diversity

“…Diversity antennas can effectively improve channel reliability and reduce the influence of multipath fading without increasing the power of the signal transmission, 1 which are divided into three types, including spatial diversity antenna, 2,3 polarization diversity antenna, [4][5][6] and pattern diversity antenna. [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] The pattern diversity antenna can reduce the interference of noise and the system coupling, improving radiation efficiency. A wide beam coverage can be achieved with pattern diversity without additional spectrum resources.…”

“…One is to integrate radiation units with various radiation patterns. [8][9][10][11][12][13][14][15][16] Li et al 8 designed an antenna with a broadside pattern and omnidirectional pattern by inserting a SIW cavity at the center of the patch antenna. A monocone antenna and a microstrip antenna are combined to generate two different patterns.…”

“…The techniques for realizing pattern diversity can be categorized into two classes until now. One is to integrate radiation units with various radiation patterns 8–16 . Li et al 8 designed an antenna with a broadside pattern and omnidirectional pattern by inserting a SIW cavity at the center of the patch antenna.…”