其中一個解釋，但也只解釋了band13，并未解釋清band 14
FDD在700MHz頻段里規(guī)定了個公共安全頻段(不知道是干嘛的)，而band13的高頻段相對于低頻段更靠近這個公共安全頻段。為了減小Band13對公共安全頻段的干擾，使低功率的用戶設備在高頻段發(fā)送，高功率的基站在低頻段發(fā)送。
不過詭異的是，在36.101 a00版本里的band14也是上下行倒置的，這樣其下行頻帶正好靠近公共安全頻譜，這樣豈不是干擾更大了，這點很奇特。

ANSWER: Band 13 [UL = 777 MHz-787 MHz & DL = 746 MHz-756 MHz] has the uplink and downlink reversed! In contrast to all other FDD bands in the table (and many other bandplans elsewhere), in this band, the higher frequency is allocated to the mobile device and the lower frequency to the base station. The normal practice of FDD paired band allocation has to do with attenuation properties of the carrier frequency and the availability of the power. The mobile side has usually been allocated the 揺asier� lower-frequency portion of the band which experiences smaller amount of attenuation and therefore requires less power for closing the uplink. A reversal of this allocation strategy in band 13 is a sure sign that some other problem is lurking in the background, namely interference in the form of spurious emissions. s4fads13東K:JFD()$#_本文來自移動通信網gg1fic3.cn,版權所有
The 700MHz band is divided into four paired blocks, A, B, C and D (an unpaired E Block is also available). The A and B blocks are guard bands. The C blocks (LTE Band 13) in this upper 700MHz band were the main object of last year抯 auction. 12MHz in the middle of this spectrum belongs to the Public Safety.
什21f3dsaK:JFD()$#本文來自移動通信網gg1fic3.cn,版權所有