空中接口学园--DL Assignment reception中的NDI问题

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>>>>  DL Assignment reception中的NDI问题

-- 作者：Guest
-- 发布时间：2012-04-12 22:50:24
协议中说：
Downlink assignments transmitted on the PDCCH indicate if there is a transmission on the DL-SCH for a particular UE and provide the relevant HARQ information.
When the UE has a C-RNTI, Semi-Persistent Scheduling C-RNTI, or Temporary C-RNTI, the UE shall for each TTI during which it monitors PDCCH:
- if a downlink assignment for this TTI has been received on the PDCCH for the UE’s C-RNTI, or Temporary C RNTI:
- if this is the first downlink assignment for this Temporary C-RNTI:
- consider the NDI to have been toggled.
- if the downlink assignment is for UE’s C-RNTI and if the previous downlink assignment indicated to the HARQ entity of the same HARQ process was either a downlink assignment received for the UE’s Semi-Persistent Scheduling C-RNTI or a configured downlink assignment:
- consider the NDI to have been toggled regardless of the value of the NDI.
这边NDI认为翻转有什么用啊，NDI初始值是0还是1，为什么最后一句说忽略NDI的值，认为NDI值翻转了。这段伪代码实在看不太懂，请tom老师分析指导下啊，谢谢啦！

--  作者：tom
--  发布时间：2012-04-13 07:39:00
这是36.321中5.3节，也就是LTE MAC协议的一部分，NDI是New Data Indicator，也就是HARQ所需的参数。
  说实话，我目前还没有研究过这块，建议你网上先看看别人是怎么理解的。万变不离其宗，HARQ就是要区分首发与重传。

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