Experimental results of non-radiative calibration of a tower top adaptive array

The need for calibration in antenna arrays is a persistent challenge and is one of the impediments to their widespread integration into communication infrastructures. The choice of antenna array structure dictates the means by which calibration can be achieved. The antenna structure used here is a distributed source array with an interconnected measurement structure for calibration. This non-radiative approach was taken to remove the need for external calibration sources, or computationally expensive modelling. This approach requires a calibration algorithm to utilise the measurement structure to get the best results. This paper will present a set of three such calibration algorithms used on an experimental setup to show the effectiveness of such calibration.