Multiresolution PPM for Broadcasting over Asymmetric Photon Counting Channels

In this letter, we address the problem of broadcasting to receivers with different bandwidths using pulse-position modulation (PPM). A new multiresolution PPM scheme is developed for such a scenario. We show how to construct the scheme for various settings and analyse its performance in the solar-blind region of the ultraviolet (UV) spectrum, where photon counting is attractive. Our key result is that the proposed scheme can increase information rate compared to time-sharing (TS) by superimposing information. © 2006 IEEE