Abstract

Direct intensity modulation of LEDs has been widely used for analog optical fiber systems. Nonlinear distortion of LEDs has been a major limitation of the performance of such systems, especially in frequency division multiplexed (FDM) telephone transmission systems. The nonlinearity- compensation technique of using a second LED in an optical transmitter was reported by Patterson et al.¹ revealing good improvement of nonlinearity. Because of the temperature dependence of emission power of the second LED, however, optical transmitters using this technique are very sensitive to ambient temperature variations.

© 1982 Optical Society of America