Simultaneous remote transfer of accurate timing and optical frequency over a public fiber network

A two-way method to simultaneously transfer an ultra-stable optical frequency and an accurate timing over a fiber links is presented. The ultra-stable laser acts as frequency standard and as carrier for timestamps. Timestamps signals are encode by phase modulation with a spread spectrum pseudorandom modulation at 20 Mchip/s, provided by a pair of two-way satellite time transfer modems, one for each direction.