A novel hybrid of adaptive array and equalizer for mobile communications

The combination of the adaptive array and equalizer (AE) has been developed for suppressing the cochannel interference and the intersymbol interference (ISI) in mobile communications. In this paper, a novel hybrid of the adaptive array and equalizer (NHAE) system is proposed to combat the problems of insufficient degrees of freedom and mainbeam multipath interferers. The NHAE utilizes a modified training sequence to adjust the weight vector of the array that leads the array to cancel only the cochannel interferers. The ISI which is caused by the multipath interferers and the transmission system is removed by the equalizer following the array. Therefore, the array in the NHAE may need a fewer number of the elements than the conventional array which cancels both the cochannel interferers and multipath interferers. Besides, the presence of the mainbeam multipath interferers, which may seriously degrade the performance of the AE, has much less effect on the NHAE since it is suppressed by the equalizer instead of by the array. Simulation results are presented to demonstrate the merits of the NHAE.