A low bias stabilization method for deeply-modulated analog photonic links

In this paper, we propose and experimentally demonstrate a novel dither-free low bias stabilization method with circulators-assisted in deeply-modulated analog photonic links. The stabilization is achieved by reversely transmitting and power locking a lightwave along the Mach-Zehnder modulator (MZM). Using this technique, bias locking at a low bias position with less than ±0.3 degree phase deviations is achieved even when the input RF voltage is as high as 1.4 Vπ. This low bias stabilization method is relatively simple and convenience but effective and accuracy, so that it is potentially to be applied in radio-over-fiber links.