A simple beamforming network for 802.11b/g WLAN systems

An IEEE 802.11 b/g WLAN beamformer is presented here. The system comprises of a beamforming network with controller modules integrated onto a PCB, and 4 equispaced monopole antenna array. A beamforming network is realised using cost effective power dividers, delay lines, and digital attenuators, as an alternative method to replace costly digital phase shifters. The main lobe can be steered in all directions on the H-plane. The measured radiation patterns showed that this transceiver system is fully configurable using software control and steering accuracy is better than ±5°, for both transmitting and receiving modes. Programs were written to detect the angle-of-arrival of signals, and facilitate automated beam steering.