Viability of using intelligent (smart) antenna systems in GSM cellular networks in Africa

A study was conducted to ascertain the viability of using smart antennas in GSM cellular networks in Africa to control interference, increase capacity, transmission power savings and cost-effectiveness. It was shown that a smart antenna could steer the signal in the specified directions arrival. In the simulation, the radiation patterns properly steered towards -30° and 60° angles of mobile location. It was also shown that, the probability to drop a call in presence of interference (outage probability) with use of smart antennas could reduce from 1 to 0.001, meaning fewer call drops in presence of interference. It was further illustrated that, when the received power requirement at the mobile remains the same with M-element array (smart antenna) at the base station, the output power from amplifiers is reduced by M^-2 and total transmit power is reduced by M^-1. Business case analyses showed that, capital spent on infrastructure is recouped quickly when smart antennas are deployed. With 15% deployment in a 20 BTS urban network (case study), cell capacity increase, number of base stations reduction, transmission power savings and antenna tilting cost savings amounted to more than R108 million/5 year period (case study).