Coherent analog optical links: design, performance and potential applications

Coherent analog optical links offer several important advantages over conventional direct detection links: better receiver sensitivity, possible use of angle modulation and easy separation of WDM signals and frequency translation. We propose a novel coherent AM-WlRNA optical link, and analyze and optimize its performance. With proper system design, the coherent AM link is insensitive to the laser linewidth. We then compare the performance of the coherent link with that of a direct detection link for two applications: point-to-point links and distribution networks. For typical system parameters, the coherent AM link provides better performance than the direct detection link