• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Spread Codes Design and Performance Analysis for Optical CDMA Systems

Lo, Ho-tai 30 August 2006 (has links)
The most two important concern in CDMA code design, one is the properties of spreading codes correlation, and another one is the number of users. The correlation properties will influence BER (bit error rate) of the system directly, and the number of users will express the system capacity. In optical-CDMA system, optical spreading code is impossible to achieve idea correlation properties. Because of the optical sequence is consisted of ¡¨0¡¨¡B¡¨1¡¨. We prove it after. According to the result we can define the best properties of correlation of the optical complementary codes. The ideal of auto-correlation is 0( ) and the optimum cross-correlation is 1( ). According to the requirement of the optimum complementary codes we must first to decide the value of the best threshold and prove it. The properties of correlation are satisfied with optical prime-hopping complementary codes that we architecture. We analysis the performance of the prime-hopping complementary codes in optical CDMA. Because of the hits of MAI decrease we can support most number of users, so we can clearly find the system with the prime-hopping complementary codes has the better performance.

Page generated in 0.0573 seconds