6.5.3 Change of TFC

25.1013GPPRelease 17TSUser Equipment (UE) radio transmission and reception (FDD)

A change of TFC (Transport Format Combination) in uplink means that the power in the uplink varies according to the change in data rate. DTX, where the DPDCH is turned off, is a special case of variable data, which is used to minimise the interference between UE(s) by reducing the UE transmit power when voice, user or control information is not present.

6.5.3.1 Minimum requirement

A change of output power is required when the TFC, and thereby the data rate, is changed. The ratio of the amplitude between the DPDCH codes and the DPCCH code will vary. The power step due to a change in TFC shall be calculated in the UE so that the power transmitted on the DPCCH shall follow the inner loop power control. The step in total transmitted power (DPCCH + DPDCH) shall then be rounded to the closest integer dB value. A power step exactly half-way between two integer values shall be rounded to the closest integer of greater magnitude. The accuracy of the power step, given the step size, is specified in Table 6.8. The power change due to a change in TFC is defined as the relative power difference between the mean power of the original (reference) timeslot and the mean power of the target timeslot, not including the transient duration. The transient duration is from 25μs before the slot boundary to 25μs after the slot boundary.

Table 6.8: Transmitter power step tolerance

Power step size (Up or down) P [dB]	Transmitter power step tolerance [dB]
0	+/- 0.5
1	+/- 0.5
2	+/- 1.0
3	+/- 1.5
4 ≤ Δ P ≤10	+/- 2.0
11 ≤ Δ P ≤15	+/- 3.0
16 ≤ Δ P ≤20	+/- 4.0
21 ≤ Δ P	+/- 6.0

The mean power of successive slots shall be calculated according to Figure 6.4.

Figure 6.4: Transmit template during TFC change

6.5.3.1A Additional requirement for UL OLTD

For UE with two active transmit antenna connectors in UL OLTD operation, the minimum requirements specified in sub-clause 6.5.3.1 apply at each transmit antenna connector.

6.5.3.1B Additional requirement for UL CLTD

A change of output power is required when the TFC, and thereby the data rate, is changed. The ratio of the amplitude between the DPDCH codes and the DPCCH code will vary. The power step due to a change in TFC shall be calculated in the UE so that the power transmitted on the DPCCH shall follow the inner loop power control. The step in total transmitted power (DPCCH + S-DPCCH + DPDCH for UE configured in UL CLTD activation state 1, and DPCCH + DPDCH for UE configured in UL CLTD activation state 2 or activation state 3) shall then be rounded to the closest integer dB value. A power step exactly half-way between two integer values shall be rounded to the closest integer of greater magnitude. The accuracy of the power step, given the step size, is specified in Table 6.8 at each transmit antenna connector. The power change at each transmit antenna connector due to a change in TFC is defined as the relative power difference between the mean power of the original (reference) timeslot and the mean power of the target timeslot, not including the transient duration. The transient duration is from 25μs before the slot boundary to 25μs after the slot boundary.

6.5.3.1C Additional requirement for DB-DC-HSUPA operating simultaneously with CS

For UE supporting DB-DC-HSUPA operating simultaneously with CS, the minimum requirements specified in sub-clause 6.5.3.1 apply for the primary carrier.