A circularly polarised monopole antenna with switchable frequency, pattern and polarisation.

A compound reconfigurable monopole antenna (CRMA) having ability to change its frequency, polarisation and also pattern is presented in this paper. Only 6 PIN diodes are positioned on the monopole and ground to achieve reconfigurable operations and thus the antenna can operate over 8 different states. The radiation patterns of the proposed antenna can be tilted into two different directions. In each direction, the antenna can shift its operation in between two different frequency bands, and for each band, switching between two orthogonal circularly polarised (CP) radiation can be possible. A prototype is fabricated and measured. Based on various parametric analyses, a simple design guideline is also presented. By considering its overall simple configuration, low profile, and planar geometry, proposed antenna can be a useful candidate for future wireless applications like cognitive radio, 5 G devices, and so on. [ABSTRACT FROM AUTHOR]