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标题: Zadoff–Chu quence in LTE [查看完整版帖子] [打印本页]

时间: 2012-9-5 20:50

作者: hacperhacper 标题: Zadoff–Chu quence in LTE

最近看LTE相關文獻時
看到下面關於 Zadoff–Chu quence 的敘述
請問大家
對於一個 length-31 的 Zadoff–Chu quence, 為何 available sequences 是 31-1 = 30 呢？
我覺得應該是 31 個才對啊 (從 0 ~ M_{ZC}-1)

Instead, for sequence lengths larger than or equal to 36, corresponding to transmission bandwidths
larger than or equal to three resource blocks, the reference-signal sequences are defined as cyclic exten-
sions of Zadoff–Chu sequences of length M_{ZC} , where M_{ZC} is the largest prime number smaller than
or equal to the desired reference-signal sequence length. For example, the largest prime number less
than or equal to 36 is 31, implying that reference-signal sequences of length 36 are defined as cyclic
extensions of Zadoff–Chu sequences of length 31. The number of available sequences is then equal to
30 – that is, one less than the length of the Zadoff–Chu sequence. For larger sequence lengths, more
sequences are available. For example, for a reference-signal sequence length equal to 72, there are
70 sequences available.

附件: ZC.jpg (2012-9-5 20:48, 6.99 KB) / 下载次数 0
https://www.txrjy.com/forum.php?mod=attachment&aid=MTg2NjM2fDNhYjZjZTk0fDE3NTQ1ODkxMDl8MHww

时间: 2012-9-6 12:46

作者: chenphan

It should be noted though that the center subcarrier is actually not transmit-ted as it coincides with the DC subcarrier. Thus, only 62 elements of the length-63 ZC sequences are
actually transmitted (element X32 PSS is not transmitted).

时间: 2012-9-6 12:47

作者: chenphan

时间: 2012-9-7 10:52

作者: hacperhacper

chenphan 发表于 2012-9-6 12:47
It should be noted though that the center subcarrier is actually not transmit-ted as it coincides wi ...

在 downlink 方向, DC subcrrier 沒有被使用. 但是在 uplink 方向, DC subcarrier 有被使用. 所以我覺得 length-31 的 Zadoff–Chu squence, available sequences 應該是 31 個 (包含 DC subcarrier). 這樣的說法不知道那邊錯誤了？

时间: 2012-9-9 06:49

作者: chenpjh

是的，DC子载波没用。

时间: 2012-9-9 22:09

作者: hacperhacper

chenpjh 发表于 2012-9-9 06:49
是的，DC子载波没用。

上傳方向，DC載波有使用

时间: 2012-9-17 16:06

作者: dtmyjt

上行方向DC子载波是被用作干啥的了？有晓得的没？同步信道？

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