Dynamic range of optically amplified RF optical links

We investigated, theoretically and experimentally, the effect of optical am plification on the dynamic range performance of both externally modulated d irect detection and coherent RF optical links. Our results show that, for l ow- to medium-loss links, a direct detection link with or without an optica l amplifier, depending on the loss range, gives the best dynamic range. For high-loss links, the best link to use is a coherent link with the optical amplifier after the modulator. We also showed that the position of an ampli fier is an important design parameter; it determines whether or not an opti cal amplifier improves the link's dynamic range.