PERFORMANCE ANALYSIS OF LOW CODE RATE AND HIGH CONSTRAINT LENGTH CONVOLUTIONAL ENCODER ON OIDMA SYSTEM WITH AVALANCHE PHOTODETECTOR

IDMA (Interleave Division Multiple Access) is a prominent technology used in the 4G and 5G communication system. IDMA is a recent multiple access technique through which multiple access interference (MAI) and inter symbol interference (ISI) can be minimized in the communication network. The optical fiber channel provides the efficient bandwidth utilization for improving the performance of O-IDMA system. In this article, the impression of low code rate (1/2) convolutional codes with high constraint length (L = 7 and L = 9) has been analyzed on optical coded OIDMA system. The code rate depends on number of Ex-OR gates and constraint length depends on number of memory elements new algorithm for convolutional encoder which satisfies above condition of code rate and constraint length. Tree inter-leavers having larger memory, less power consumption and simplified design features, makes it useful to improve the quality of O-IDMA system. In present article various architecture of convolutional encoders are designed by varying the feedback connections and are tested for observing the BER performance of O-IDMA system implemented on MATLAB. Tree inter-leavers in taken into account for analysis purpose and BER with increasing number of users is plotted in graphical and tabular manner.