Circuit techniques for 10 and 20 Gb/s clock recovery using a fully balanced narrowband regenerative frequency divider with 0.3 mu m HEMTs

SDH/SONET optical networks have so far been standardized for data rates up to 10 Gb/s (9.95328 Gb/s) in the synchronous transfer module level STM-64/STS192. The next higher level may possibly be a rate of 40 Gb/s. taking account of the difficulties of manufacture of 40 Gb/s devices and ICs, several experimental transmission systems have been demonstrated at 20 Gb/s.