A SCHEME FOR OPTICAL PULSE GENERATION USING OPTOELECTRONIC PHASE LOCKED LOOPS

Madhumita Bhattacharya

Abstract: A new scheme of optical pulse generation using multiple optoelectronic phase locked loops is proposed. The principle of the scheme is combining three or more coherent optical waves having equal frequency separation. The coherencies of the optical waves are attained by the use of optoelectronic phase locked loops. The repetition frequency of the generated optical pulse is equal to the frequency of the reference microwave/ millimeter wave signal source used in the phase locked loop. The intensity profile of the generated optical pulse and the pulse width are calculated. If four coherent optical carriers are combined, the generated optical pulse has a typical width of 2.4 picoseconds. In the proposed scheme the central frequency of the optical pulse and the repetition frequency can be varied. Since in this scheme, the superimposed optical waves are phase locked the associated phase noise of the optical pulse will be low.

Keywords: optical pulse generation, optoelectronic phase locked loop, pulse repetition frequency, laser diode, photodiode

DOI: https://doi.org/10.15623/ijret.2014.0303064