Abstract
Optical code division multiple access (OCDMA) shows limitations in terms of the inefficient bandwidth utilization and low spectral density with one-dimensional (1D) codes. To overcome these limitations, a novel design is presented using a two dimensional (2D) spectral/spatial multiwavelength coding scheme. The proposed code is constructed using a 1D balanced incomplete block design (BIBD) technique. Theoretical and analytical results indicate that the proposed code provided improvement in the number of simultaneous users, code construction, and cross-correlation and minimized noise. Moreover, the bandwidth requirements can be minimized, and it can provide flexibility in addressing code sequences. Finally, results were compared with existing spectral-spatial 2D codes such as diagonal eigenvalue unity (DEU) and 2D diluted perfect difference (DPD). It was observed that the 2D-BIBD code fulfilled optical transmission needs with minimum effective source power (Psr = −27.5 dBm) when compared to 2D-DEU (−26.5 dBm) and 2D-DPD (−25.5 dBm) codes. Overall, our results suggested that the performance of BER for the proposed code was 72% and 22% higher than the existing 2D-DPD and 2D-DEU codes, respectively.
Highlights
The main parameters used to measure performance of Optical code division multiple access (OCDMA) system are available bandwidth, signal-to-noise ratio (SNR), and the cross-correlation between coded signature sequences [1]
Wavelengths based on user data can be chosen using low cost fiber Bragg grating (FBG) filters for encoding purposes in case of spectral amplitude coding (SAC) based OCDMA system
1 dimension (1D) codes used in SAC systems have some drawbacks such as large code length resulting in complex code construction and restrained code cardinality and bandwidth
Summary
The main parameters used to measure performance of Optical code division multiple access (OCDMA) system are available bandwidth, signal-to-noise ratio (SNR), and the cross-correlation between coded signature sequences [1]. A coding scheme with optimal length and ideal cross correlation code properties is desirable because it can provide enhanced system capacity in terms of data rate and code cardinality For these reasons, 2D codes have been proposed and designed by combining two different dimensions of CDMA. In the OCDMA environment, 2D-BIBD codes performed better than 2D extended set prime code families due to their easy code construction, optimum temporal length, quantity of users, and good auto and cross-correlation properties [20]. The proposed code construction method is easier compared to the existing ones These codes are further implemented in a SAC-OCDMA system environment. OCDMA networks and constructed using a 1D-BIBD code matrix This matrix includes the estimation of the weight values and the number of users, which corresponds to code length.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
