文件名称：变长Walsh码-华为CDMA2000
文件大小：3.95MB
文件格式：PPT
更新时间：2024-05-13 05:52:00
cdma
变长Walsh码 Data rate -bps- 对于不同的信息速率，使用不同的长度的Walsh码，以确保最后的扩频码片速率为1.2288MChips CDMA 核心技术 64 4 8 16 32 1 2 9600 19200 38400 76800 153600 307200 614400 W 0 1 =0 W 0 2 =00 W 1 2 =01 W 0 4 =0000 W 2 4 =0011 W 1 4 =0101 W 3 4 =0110 W 0 8 =00000000 W 4 8 =00001111 W 2 8 =00110011 W 6 8 =00111100 W 1 8 =01010101 W 5 8 =01011010 W 3 8 =01100110 W 7 8 =01101001 ( W 0 16 ,W 8 16 ) ( W 4 16 ,W 12 16 ) ( W 2 16 ,W 14 16 ) ( W 6 16 ,W 14 16 ) ( W 1 16 ,W 9 16 ) ( W 5 16 ,W 13 16 ) ( W 3 16 ,W 11 16 ) ( W 7 16 ,W 15 16 ) Enhancements of CDMA2000 include the use of Walsh spreading factor to attain high data rates on the forward link. Variable Walsh spreading uses the tree structure for recursively constructing Walsh codes of the longer lengths. Higher data rates for the user can be obtained by using the shorter Walsh code. However ,use of one of the shorter codes precludes using any longer code that are derived from it.