The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 18, 2007
Filed:
Feb. 27, 2002
LI Hao, Sichuan Province, CN;
Pingzhi Fan, Sichuan Province, CN;
Li Hao, Sichuan Province, CN;
Pingzhi Fan, Sichuan Province, CN;
The Research Institute of Telecommunications Transmission, Beijing, CN;
Southwest Jiao Tong University, Sichuan Province, CN;
Abstract
This invention involves a two-level variable chip rate spreading and despreading method used in CDMA systems. The total spreading gain is the product of the two level spreading factors. Orthogonal sequences, ZCZ sequences and Pseudo-Noise (PN) sequences can be employed as the first- and second-level spreading codes. By employing the two-level spreading method, the interference existing in the systems can be suppressed efficiently and the system performance can be improved significantly.