講演情報
[11a-E219-5]Demonstration of 50 Gbit/s Coherent Single Polarization QPSK System for long-haul communication
〇(D)Sheela Rani1, SUKHBIR SINGH1, SATYA PARKASH SINGH1 (1.NSUT DELHI INDIA)
キーワード：
QPSK TECHNIQUE、HIGH SPEED、LONG HAUL
This paper investigated the performance of 50 Gb/s single polarization coherent Quadrature Phase Shift Keying (QPSK) system with different range of optical distances and also focused on bias voltage of LiNb Modulator and power of CW laser. The performance is evaluated in terms of the CW power, Voltage, length and the BER values by varying the distance from 40 km to 240 km. The wavelength of CW laser and local oscillator is 1550nm and 1550.01 nm respectively. In this case, the value of BER starts by dropping when bias voltage increases to reach the minimum at the optimal operation point. For -19.9, -19.5, -19.0 v the BER value is achieved and this is one of the ideal operating points. BER reached its minimum value, reflecting excellent signal quality and accurate coherent detection. This system gives the best results for 80 km to 200 km without any DCF fiber and where the standard attenuation in fiber is 0.2 dbm and the insertion losses are 5 dBm. It is found that this system provides Clear Spectrum, Constellation Diagram and lowest BER at 100 km.