A Low-Profile Wideband Microstrip Antenna With Pattern Diversity Based on Composite Right/Left-Handed Transmission Lines

A low-profile wideband microstrip antenna is proposed based on the structure of composite right/left-handed transmission lines (CRLH TLs). The dimensions of the proposed antenna are 64 x 64 x 4 mm. The impedance matching bandwidth is 5.05-5.92 GHz (16.5%). The unit cell of the CRLH TLs is a mushroom structure. Several different resonant modes with different radiation patterns are excited to obtain the pattern diversity. Particularly, TM10 and TM20 modes are merged to realize a wideband performance with broadside radiation pattern, whereas the TM20 mode is used to realize a conical radiation pattern. The simulations and measurements are in good agreement, and the envelope correlation coefficient shows that the proposed antenna owns an excellent diversity performance.

Automated summary

The proposed low-profile wideband microstrip antenna, based on composite right/left-handed transmission lines (CRLH TLs), features a compact size and a wide impedance matching bandwidth. By exciting different resonant modes, the antenna achieves pattern diversity and excellent performance consistency, as confirmed by simulations and measurements.