GPRSpowercontrol-TS0508规定.docVIP

10.2.2 BTS output power Downlink power control can only be used when the serving BCCH or CPBCCH and the used PDCH frequencies are in the same frequency band. On the PDCHs that contain PBCCH or PCCCH, the BTS shall use constant output power, which may be lower than the output power used on BCCH. The power reduction (Pb) used on PCCCH, relative to the output power used on BCCH, is broadcast on PBCCH. For COMPACT, on the blocks that contain CPBCCH, CPCCCH, CFCCH, or CSCH, the BTS shall use constant output power. On PTCCH/D, the BTS shall use the same output power as for PBCCH, or BCCH if PBCCH does not exist. As an exception to this, the output power for some of the PTCCH/D blocks may be lower in some cases (e.g. with adaptive antennas), but with no requirements for the MS to decode them. The network is however responsible to provide each MS with required TA information. On other PDCH radio blocks, downlink power control may be used. The BTS shall use the same output power on all four bursts within one radio block except for bursts transmitted on the BCCH carrier. Thus, a procedure may be implemented in the network to control the output power of the downlink transmission based on the Channel Quality Reports. 一个radio block的4个burst上使用相同的功率。 可以根据Channel quality report来控制下行输出功率。 On PDCHs that do not contain PBCCH or PCCCH and do not use downlink power control (as indicated in the assignment message), the BTS shall use a constant output power with the exception that it is not required to transmit on every block. If the output power used on the transmitted blocks is not equal to (BCCH level – Pb) then the MS is not required to fulfil 3GPP TS?05.05 requirements for the first 25 blocks addressed to this MS. Two methods of downlink power control exist. Power control mode A can be used for any allocation method. Power control mode B can only be used for fixed allocation. The method used is determined by the BTS_PWR_CTRL_MODE as sent in the assignment command. 功控模式A适用于动态配置和静