Performance Analysis of WDM Technique in Optical Fiber Link

Abstract

Wavelength division multiplexing technique is used in fiber optic transmission to incorporate multiple light wavelengths in sending data over the same medium. During the 1980s, fiber optic data communications modems used low-cost LEDs to put near-infrared pulses onto low-cost fibers. Continuous-wave (CW) operation of a laser means that the laser is continuously pumped and continuously emits light. The emission can occur in a single resonator mode (single-frequency operation) or on multiple modes. WDM systems used 1550nm wavelengths for multi-channel systems. In 1550nm region – the fiber attenuation is lowest. In this thesis, we have used 8 channels WDM system and analyzed the average of each channel bit error rate. We’ve designed the system in two times-one is with amplifier and another is without amplifier. We analyzed and compared the temperature dependence, power consumption, BER of 8-QAM modulation schemes at 1550 nm wavelength for CW based optical link. It’s found that the bit error rate of the system (with amplifier) is kept fixed at 10 Gb/s and fiber length is increasing 10 km. And the bit error rate of the system (Without amplifier) is kept fixed at 10 Gb/s and also fiber length is kept fixed at 10 km. We also analyzed the bit error rate for 0.25m to 2m in automobile. In future it will help us to use optical fiber in automobile. The working temperature range extends up to 1250C for 1550 nm and we also analyzed bit error rate in room temperature. As increasing temperature reduces a major portion of q-factor. Optical access networks will be a challenge in the future when end-user demand outgrows current network limit. Wavelength division multiplexing (WDM) has been managed an ideal solution to extend the limit of optical networks without definitely changing the fiber infrastructure. In this thesis we investigate key issues and review enabling technologies for upgrading current-generation optical access networks with WDM techniqu