Performance Investigation of NRZ-DQPSK, CSRZ-DQPSK and MDRZ-DQPSK Modulation Techniques for 450 Channel UD-WDM System for Long Haul Communication: ANALYSIS OF MODULATION TECHNIQUES FOR LONG HAUL UD-WDM SYSTEM. JSIR [Internet]. 2023 Aug. 16 [cited 2026 May 15];82(08):870-84. Available from: https://or.niscpr.res.in/index.php/JSIR/article/view/1053