Adaptive Digital Beamforming Antenna Array for High Speed Communications

The rapidly increasing demand for PCS has provided the impetus to design adaptive antenna arrays to improve spectral efficiency and enhance system capacity. With increasing data rate in some PCS application like DECT( Digital European Cordless Telecommunications), higher BER would degrade the system performance further. An adaptive antenna array testbed using 12 elements was built to evaluate its performance on high data rate mobile communications in an indoor environment for DECT applications. The simultaneous data sampling rate on the elements is about 3.5 MHz. A system design of the adaptive array using digital beamforming for off-line processing is presented. An indoor field trial was conducted to demonstrate performance improvement in terms of BER and SNR using adaptive beamforming techniques like blind algorithms over switched diversity method. Spatial Division Multiple Access (SDMA) will also be discussed to demonstrate the system capacity enhancement using adaptive array for DECT. Experiments have been conducted to demonstrate multipath mitigation, interference suppression and capacity enhancement.