Linearity in Fiber-Optic Analog Transmission System Using Laser Diodes

Ken-ichi SATO  Koichi ASATANI  

IEICE TRANSACTIONS (1976-1990)   Vol.E64   No.10   pp.646-652
Publication Date: 1981/10/25
Online ISSN: 
Print ISSN: 0000-0000
Type of Manuscript: PAPER
Category: Transmission Systems

Full Text: PDF(461.5KB)>>
Buy this Article

This paper investigates the linearity performance of analog video transmission systems which use semiconductor laser diodes. The main origins of system linearity degradation are shown to be reflected laser light and speckle noise. It is demonstrated that a laser with an external reflector produces a nonlinear response which degrades the laser modulation properties. It is also revealed that in analog video transmission systems using graded-index multimode fibers, speckle noise is so serious that a reduction in laser coherency is essential, and a new technique employing an optical feedback scheme to reduce speckle noise in investigated. The high quality of results obtained from transmission tests employing the proposed method have confirmed the feasibility of analog video transmission using semiconductor laser diodes.