Title :
Design and performance analysis of code families for multi-dimensional optical CDMA
Author :
Ravi Kumar, M. ; Pathak, Sant ; Chakrabarti, N.B.
Author_Institution :
G.S.Sanyal Sch. of Telecommun., Indian Inst. of Technol., Kharagpur
fDate :
8/1/2009 12:00:00 AM
Abstract :
A code design algorithm for application in multi-dimensional optical code division multiple access (MD-OCDMA) for asynchronous optical fibre communication is proposed. Two-dimensional (2D) wavelength-time or space-time OCDMA and three-dimensional (3D) space-wavelength-time OCDMA are subsets of MD-OCDMA. Some applications and the performance analysis of the algorithm in 2D multipulse per row codes and 3D multipulse per plane codes are shown. In the applications discussed, this design ensures a maximum cross-correlation of ´1´ between any two codes. The performance metrics studied are the probability of error due to multiple-access interference for different numbers of active users and optimum temporal length for different values of cardinality. The performance analysis shows that the proposed 2D design offers very low probability of error due to multiple-access interference at lower cardinality when compared with other 2D designs using equivalent code dimension. A comparison of the proposed 3D design with an existing 3D design shows better performance at lower cardinality. The 3D designs show better performance when compared with the 2D designs.
Keywords :
code division multiple access; code division multiplexing; error statistics; optical fibre communication; radiofrequency interference; space-time codes; wavelength division multiplexing; asynchronous optical fibre communication; code design algorithm; error probability; multidimensional optical CDMA; multiple access interference; optimum temporal length; space time system; space wavelength time OCDMA; wavelength time OCDMA;
Journal_Title :
Communications, IET
DOI :
10.1049/iet-com.2008.0391