Abstract

The degradation of the bit-error-rate (BER) under optical feedback in optical fiber transmission systems is well known. Normally, BER degradation can be suppressed by employing optical isolators; however, this complicates the laser module and introduces some additional costs to the system. A laser with a high endurance level against optical feedback has been desired, to develop systems that do not require an isolator. In this paper, such as laser is experimentally shown to be possible, based on theoretical analyses. A high endurance level over the optical feedback of >1% of the emitted power is experimentally achieved in a 1.55-μm strained-QW DFB laser with a long cavity.

© 1992 Optical Society of America