An introduction to fibre-to-air for cellular applications

This paper presents fibre-to-air, a new system for feeding radio frequency (RF) signals from either the base station controller (BSC) or base transceiver station (BTS) directly to the antenna element at the air interface. The proposed system has lower transmission losses and greater power efficiency than current state-of-the-art implementations. Other advantages include fast antenna main beam steering, reduced antenna weight, and reduced susceptibility to RF interference on the feeder network. Results are presented showing measured radiation patterns for a prototype fibre-to-air antenna and those of an electronically controllable optical phase shifter.