OCDMA系统中新型正交码的设计及性能研究

为了得到性能较为良好的正交码,采用没有重复数字的全间隔集,进行了地址码的设计和系统仿真验证,设计出的正交码具有理想的相关性和灵活的码字容量。分析整个系统,在考虑各种噪声和多址干扰的影响下,推导出正交码的误比特率公式。自行设计并搭建了采用光纤延时线作为编解码器的异步光码多分址系统。结果表明,该正交码能够适应更多用户的需求,通过误比特率公式计算和系统仿真得到的结果都较为理想,此研究对需要大容量的光码多分址系统的进一步发展具有一定的帮助。

Design and performance study on novel optical orthogonal codes in OCDMA systems

In order to get the optical orthogonal codes (OOC) with good performance, all-interval-set with no duplicate number was used. After design and system simulation, OOC had ideal correlation and flexible code capacity. The formula of bit error rate (BER) was derived considering all kinds of noise and multi-user interference. Asynchronous optical code division multiple access (OCDMA) system was designed and constructed with fiber optic delay lines as encoders and decoders. The result shows that the OOC can adapt to the demands of more number of users. The consequence is satisfactory both from the calculation of BER formula and from system simulation. The research is helpful for further development of OCDMA systems with high capacity.