Cell Range Extension Techniques for Wide-Area Ubiquitous Network

This paper describes a newly developed wireless access system for the wide area ubiquitous network (WAUN), a large cell-based public sensor network. It introduces two key technologies to achieve WAUN with wide area coverage. The first is a digitalized radio over optical fiber (DROF) subsystem that allows cost-effective commercial packet based networks to transfer wireless RF signals among distributed access points. The second is a frequency offset transmitter diversity scheme that achieves sub optimal diversity gain without rate loss, regardless of the number of antennas, by using intentional and orderly frequency offset.