【摘要】 提出了一种适合于光码多分址(OCDMA)频域/时域(λ-t)的二维线性组合码(LCC)新的构造方法,设计了编/解码方案,分析了系统性能。研究表明:影响LCC性能的参数主要有其子码字数和码字中相同子码字的个数。随着LCC的子码数的增加,OCDMA系统的用户容量显著提高;通过改变LCC的设计参数,系统的误码率(BER)得到改进,当LCC的子码字数确定时,BER随系统中LCC码字中相同子码字的个数的最大值的增加而劣化;当LCC码字中相同子码字的个数的最大值一定时,BER随LCC的子码字数的增加而得到改进。更多还原

【Abstract】 The scheme of the wavelength-time(λ-t) optical code division multiple access(OCDMA) system with a linear combinatorial code(LCC) proposed first in the paper is designed.The capacity and the bit error rate of system are analyzed.The result shows that two parameters,named as the number of sub-codeword and the maximum number of same sub-codeword in a LCC,determine the preference of the LCC.In LCCs system,the capacity is improved notably with the increase of the number of sub-codeword,and the bit error rate can be controlled by varying the combinatorial parameters of the code.When the number of sub-codeword is constant,the bit error rate is degraded with the increase of maximum value of same sub-codeword in all LCCs system.When the maximum value of same sub-codewords in all LCCs is fixed,the bit error rate is improved with the increase of the number of sub-codeword.更多还原