Analysis of mobile terminal diversity antennas

Antenna diversity has for many years been deployed at the base station to provide significant diversity gain. More recently, diversity has also been implemented at the mobile and it has been observed through measurement that antennas still give low correlation even when closely spaced. The paper analyses why decorrelation exists mainly due to angular diversity effects from the two antennas and mutual coupling between them. Although there is low correlation there is still often a reduction in efficiency when antennas are close together, so this is also investigated to see what scope there is for diversity at the mobile. The impact on efficiency will then determine what effect is made on the diversity system as a whole.