A planar diversity antenna for wireless handsets

We introduce a compact integrated antenna that has two feed ports with more than 20 dB isolation between them. The significance of the design is that it can be utilized in compact wireless communication handsets to provide diversity signals or act as a duplexer allowing the receive and transmit signals to be well isolated. The antenna design is based on merging two patch antennas together and experimental results at 2220 MHz include radiation patterns, S-parameters and signal correlations between ports. These demonstrate that the envelope cross-correlation between ports is less than 0.1 making the antenna suitable for diversity applications.