Designing reverberation chambers for measurements of small antennas and wireless terminals: Accuracy, frequency resolution, lowest frequency of operation, loading and shielding of chamber

The last five years the reverberation chamber has been developed to an accurate instrument for measuring the performance of small antennas and active mobile terminals in Rayleigh fading. The present paper gives an overview of the research done by the authors in relation to achieving an accuracy of 0.5 dB RMS or better, when measuring efficiency and radiated power. The accuracy has been verified by comparison with measurements in anechoic chambers, and between reverberation chambers of different size, and from participation in benchmarking of measurement ranges done within ACE (Antenna Center of Excellence, a European Network of Excellence). There have also been developed procedures for measuring quantities that are specific for the Rayleigh environment, such as diversity gain, MIMO capacity, and static as well as dynamic receiver sensitivity at certain data error rate (BER or FER). The paper will describe important topics related to the mode stirring and loading of the chamber, such as the accuracy, frequency resolution, average transfer function, and the system bandwidth when measuring active terminals. Numerical simulations play an important role in controlling the chamber performance.