 channels. Thus, power control steps in the dedicated physical channels apply also to the RACH message part, with the differences that [11]: BC is the gain factor for the control part (similar to DPCCH); B is the gain factor for the data part (similar to DPDCH); no inner or fast loop power control is performed, but open loop power control. Before the uplink power control procedure simultaneously controls the power of a DPCCH and its corresponding DPDCHs when present, high layers set the initial uplink DPCCH transmit power. The network determines this relative transmit power offset between DPCCH and DPDCHs using the gain factors signalled to the UE. The inner or fast power control loop operation adjusts the power of the DPCCH and DPDCHs in steps of 1 dB or multiples of one and smaller steps through emulation at 1500 Hz com- mand rate. The DPCCH uplink transmit power takes place immediately before the start of its pilot field. This change occurs with respect to its previous value derived by the UE, i.e. ADPCCH (in dB). The previous DPCCH power value corresponds to the one used in the previous slot, except in the event of an interruption in transmission due to the use of compressed mode. In the latter case, the previous value corresponds to the one used in the last slot before the transmission gap. While in power control, the UE transmit power will not exceed a maximum allowed value, i.e. the lowest out of the terminal maximum output power and the one set by higher layer signalling. If the UE transmit power falls below the required minimum output power and the derived value of ADPCCH < 0, the UE may reduce the ADPCCH magnitude [11]. 4.3.6.1.1 The transmit power control function The uplink inner-loop power control adjusts the UE transmit power to keep the received uplink signal-to-interference ratio (SIR) at a given target, i.e. SIRtarget The serving cells in the active set estimate signal-to-interference ratio (SIRest) of the received uplink DPCH. Then they generate TPC commands and transmit them once per slot accor