Investigation of using passive repeaters for indoor radio coverage improvement

Recently, the issue of how to improve indoor radio coverage has received considerable attention. In this paper, we investigate radio coverage improvement by using passive repeaters, including both single and multiple repeaters. It is identified that the major function of the passive repeater is to change the field distribution in an indoor environment and therefore to improve the radio coverage over certain (not all) areas, while the overall power within the environment is not changed. The change of the field distribution can generate more uncorrelated signals in the area, which makes antenna diversity systems and MIMO systems more effective.