Title :
Transmission of QPSK signals using unisolated DFB lasers
Author :
Woodward, Sheryl L. ; Swaminathan, Viswanathan ; Bodeep, G.E. ; Singh, A.K.
Author_Institution :
Crawford Hill Lab., AT&T Bell Labs., Holmdel, NJ, USA
Abstract :
We have investigated the use of uncooled and unisolated 1.3 μm DFB lasers in a QPSK transmission system. Our measurements include both BER measurements and detailed analog tests on two commercial DFB lasers in cylindrical packages. Error-free transmission was observed even in the presence of back reflections as large as -8 dB. The laser relative intensity noise (RIN) was measured as a function of temperature and back reflection. The change in RIN in the temperature range -10/spl deg/C to +60/spl deg/C was less than that due to back reflections, suggesting that error-free QPSK transmission can be acheived over a large temperature range with these DFB lasers.
Keywords :
distributed feedback lasers; laser noise; light reflection; optical fibre communication; optical modulation; quadrature phase shift keying; semiconductor device noise; semiconductor lasers; -10 to 60 C; 1.3 mum; BER measurements; QPSK signal transmission; QPSK transmission system; analog tests; arge temperature range; back reflection; back reflections; commercial DFB lasers; cylindrical packages; error-free QPSK transmission; error-free transmission; laser relative intensity noise; temperature; temperature range; uncooled lasers; unisolated DFB lasers; Acoustic reflection; Bit error rate; Laser noise; Laser transitions; Noise measurement; Optical reflection; Packaging; Quadrature phase shift keying; Temperature distribution; Testing;
Journal_Title :
Photonics Technology Letters, IEEE
