Cost effective optically connected remote UWB antenna system

Ultrawide-band (UWB) is a promising short range communication technology due to its extremely low radiation power, very low operation signal-to-noise ratio (SNR), and wide bandwidth under unlicensed spectrum (3.1 - 10.6 GHz). To construct an optimal correlation receiver for UWB impulse radio, it is good to have all the incoming signal information in digital domain. However analog-digital conversion at wideband frequencies is power consuming and expensive. To take advantage of the positioning capabilities of the UWB signal a number of receivers have to be placed. For optimising the cost and the power consumption, it is a good idea to have only one receiver with a number of antennas. At UWB frequencies 3 - 10 GHz, coaxial cable based distributed antenna systems, which have previously been used for radio applications becomes impractical because of high feeder loss. Radio over fibre techniques can be used to deliver microwave communication signals to the receiver. In this paper, we present experimental results for an optically connected UWB antenna system. To make this system cost effective we use nowadays high speed, direct modulated VCSEL diodes and multimode optical fibers.