已解决问题
firstly, PDSCH EPRE(power per RE per antenna port) can be set based on CRS EPRE, and according to 36.213, the difference between PDSCH EPRE and CRS EPRE is decided by a RRC configurable parameter: P_A.
Generally, CRS EPRE is fixed and broadcasted by SIB2. and P_A is UE specific, and the value range is [-6, -4.77, -3, -1.77, 0, 1, 2, 3], so at maximum PDSCH EPRE = CRS EPRE + 3dB. The value range of CRS EPRE is -60~50dBm.
In the extreme, we can set CRS EPRE and P_A to proper value to allow a single user to use as much power as possible.
But normal practices is that it is a multi-user network, and CRS EPRE is generally set to the average power (that's 20W(per antenna port) - 10*log10(1200)=12dBm, and by the way, the 23dBm power from you calculation is wrong!), and P_A may be to 0dB. In this case, PDSCH power is 12+0+3(two branchs tranmission) = 15dBm
Generally, CRS EPRE is fixed and broadcasted by SIB2. and P_A is UE specific, and the value range is [-6, -4.77, -3, -1.77, 0, 1, 2, 3], so at maximum PDSCH EPRE = CRS EPRE + 3dB. The value range of CRS EPRE is -60~50dBm.
In the extreme, we can set CRS EPRE and P_A to proper value to allow a single user to use as much power as possible.
But normal practices is that it is a multi-user network, and CRS EPRE is generally set to the average power (that's 20W(per antenna port) - 10*log10(1200)=12dBm, and by the way, the 23dBm power from you calculation is wrong!), and P_A may be to 0dB. In this case, PDSCH power is 12+0+3(two branchs tranmission) = 15dBm
回答时间:2012-6-25 09:45
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