The most two important concern in CDMA code design, one is the spreading code correlation performance, and another one is the number of supporting users. The correlation performance will influence the system BER (bit error rate) directly, and the supporting user number will express the system capacity.
In optical-CDMA system, optical spreading code it is impossible to achieve idea correlation performance, especially in cross-correlation. Because of the optical sequence is consisted of 0¡B1 . We also prove it in chapter two. For reducing the interference of multi-user, we propose a new signature code in chapter three. The new code design approaching has a perfect correlation performance. It can achieve ideal auto-correlation. And in cross-correlation, although it can¡¦t be ideal completely. We let the sidelobe number in cross-correlation be the minimum and constraint the one amplitude is 1.
We also analysis the performance of optical-CDMA with the new signature code in chapter four. Because of it has perfect correlation characteristics, so we can clearly find the system with the new signature code has the better performance.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0804104-204410 |
| Date | 04 August 2004 |
| Creators | Lin, Yu-hsin |
| Contributors | Hsiao-Hwa Chen, Chin-Der Wann, CHAO-TANG YU |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0804104-204410 |
| Rights | not_available, Copyright information available at source archive |
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