Design and evaluation of a fully adaptive antenna for telecommunication systems
Jonas Strandell, M. Wennström, Anders Rydberg, Tommy Oberg, O. Gladh, L. Rexberg, E. Sandberg · 1997
An adaptive antenna for the DCS-1800 mobile telephony system has been designed and evaluated. The antenna is working in uplink only and has a multiplexity of two channels per frequency and timeslot. The array antenna has a circular structure and the complex weights are calculated using the sample matrix inversion method (SMI). Evaluations of the adaptive antenna in an outdoor environment show promising improvement of the carrier-to-interfererratio (C/I) of more than 30 dB. Measurements of bit-error-rate (BER) for different angular separation of the mobiles show that for an input C/I ³ -10 dB the minimum angular separation for approximately 0% BER is less than 4 degrees. INTRODUCTION The use of adaptive antennas in mobile communication systems offers a possibility to increase the system capacity. To exploit the benefits of using adaptive base station antennas, a testbed project commenced 1994 consisting of groups at the Signals and Systems group at Uppsala University and Ericsson Radio...