Time and Frequency Transfer Via the Same Wavelength

Optical fiber links have demonstrated their ability to transfer the ultra-stable clock signals. In this paper we propose a new method to transfer both time and radio frequency via the same wavelength. Time signal is encoded as a binary phase-shift keying(BPSK) to the optical carrier using electro optic modulator(EOM) and the frequency signal is modulated onto the optical carrier by an EOM amplitude modulation. We have demonstrated the experiment over 50 km fiber spools and the result shows that relative stabilities 7E-15 at 1s. Moreover, longterm timing stability is lower than 2ps. This technique may have application in Very Long Baseline Interferometry, et al.