Comparative Analysis of DCF based Dispersion Compensation Techniques in Optical Fiber Communication Link using Different Input Transmitter Conditions at 10 Gbps

In this paper, Dispersion Compensating Fiber (DCF) based various dispersion compensating techniques (pre, post and symmetrical) with different modulation format like Non Return to Zero(NRZ), Return to Zero(RZ), Carrier Suppressed Return to Zero(CSRZ) and Duo Binary(DB) along with PN, FCC and Walsh code input sequences are implemented. Simulation and analysis of these implemented techniques were done at 10 Gbps bit rate and input laser power ranging from 1 mW to 10 mW at transmission distance of 240 km using BER Analyzer in Optisystem 17.0 software. Comparison between different techniques was done in terms of Q factor and BER versus input CW laser power for different modulations and input sequences. From the analysis, it is concluded that when Walsh code as user defined input sequence are used for all the implementation, it gives higher value of Q factor and lower value of Bit Error Rate as compared to PN and FCC codes for most of the input CW laser power.

DESIGN AND PERFORMANCE ANALYSIS OF ORTHOGONAL MULTI-LEVEL CODE-SHIFTED DIFFERENTIAL CHAOS SHIFT KEYING COMMUNICATION SYSTEM

Based on Orthogonal Chaotic Vector Shift Keying (OCVSK) system and Multilevel Code-Shifted Differential Chaos Shift Keying (MCS-DCSK) system, a new Multilevel Code-Shifted Differential Chaos Shift Keying (OMCS-DCSK) modulation system is proposed and designed in this paper. New orthogonal chaotic signal sets are generated using Gram-Schmidt algorithm and Walsh code function then these signals are used for bearing information bits to achieve higher data rate and better bandwidth efficiency compared with the conventional DCSK communication system. The bit error rate (BER) analysis of the OMCS-DCSK system over additive white Gaussian noise (AWGN) and multipath Rayleigh fading channel is derived and compared with the simulation results. Also, the spectral and complexity analysis of the system are presented and compared with the conventional DCSK systems. The results show that the proposed system outperforms OCVSK and MCS-DCSK in BER performance and spectral efficiency

ANALISIS KINERJA KOMBINASI SISTEM CODE DIVISION MULTIPLE ACCESS MULTIPLE INPUT MULTIPLE OUTPUT DENGAN KODE PENEBAR WALSH PADA KANAL RAYLEIGH FADING

The increasing human population are same to the need for telecommunications. Code Division Multiple Access (CDMA) is one of the most widely used telecommunications technologies. But with the increasing number of users, this technology is no longer able to meet the needs of users. With the required capacity requirements, the CDMA system and Multiple Input Multiple Output (MIMO) technology are merged.To find out the performance of a combined CDMA MIMO system, the system was tested by increasing the number of users and Signal to Noise Ratio (SNR) where the spreading code used was the Walsh code and the channel used was Rayleigh Fading modeling. The reference value used as material for consideration are the value of Bit Error Rate (BER).The method used in testing the CDMA MIMO system is the increase number of users, starting with a single user up to 16 users and SNR values from -15 dB to a maximum of 15 dB.Where all users will be combined with the CDMA technique then it will be sent using MIMO technology. The system will be tested using a simulation of the MatLab R2012a software.The results of the simulation show the performance of the CDMA MIMO system when using SNR that is increasing high, the BER will be lower or better used for communication. Whereas for simulations using a user that increases it results in a BER value that is almost the same because of the nature of the orthogonal Walsh code so that each user does not experience interference with other users.