Error vector magnitude, intermodulation and radiation characteristics of a bandwidth and pattern reconfigurable antenna

Abstract

This letter presents the error vector magnitude (EVM), intermodulation (IM), and radiation performances of a reconfigurable antenna capable of varying its bandwidth between 3.4-3.6 and 3.1-3.9 GHz bands, and steering its main beam into three directions pertaining to ¿ ¿{-30°, 0°, 30°}andf E {0°} for each band. Two parasitically coupled reconfigurable layers located on top of a driven antenna used in conjunction with a reconfigurable feed layer employing p-i-n diode switches enable a concurrent configuration of an impedance bandwidth and a radiation pattern. The maximum realized gain of ~9 dB has been achieved for all modes of operation as shown by measurements and simulations. Measurements indicated less than -25dB (5.6%) EVM for input powers up to30 dBm and revealed that the combined effects of loose solder joints and large nonlinear response of p-i-n diodes are the main factors resulting in passive IM products.