Dual Polarised Microstrip Antenna Design for a Polarisation Shift Keying Microwave Transponder

This work describes a novel method of data transmission by means of polarisation shift keying. It analyses the system performance in terms of S/N ratio and defines the required antenna cross polarisation performance to achieve an acceptable S/N ratio. A theoretical analysis of antenna cross polarisation performance is provided. This analysis predicts a dependence of cross polarisation upon antenna substrate and angle of observation which is supported by experimental evidence. This work has also enabled accurate design criteria to be successfully applied to the fabrication of a dual feed circular disc antenna for polarisation shift keying at 2.45GHz.