Content for  TS 38.321  Word version:  18.0.0

The Single Entry PHR MAC CE is identified by a MAC subheader with LCID as specified in Table 6.2.1-2. It has a fixed size and consists of two octets defined as follows (Figure 6.1.3.8-1):

• R: Reserved bit, set to 0;
• Power Headroom (PH): This field indicates the power headroom level. The length of the field is 6 bits. The reported PH and the corresponding power headroom levels are shown in Table 6.1.3.8-1 below (the corresponding measured values in dB are specified in TS 38.133);
• P: If mpe-Reporting-FR2 is configured and the Serving Cell operates on FR2, the MAC entity shall set this field to 0 if the applied P-MPR value, to meet MPE requirements, as specified in TS 38.101-2, is less than P-MPR_00 as specified in TS 38.133 and to 1 otherwise. If mpe-Reporting-FR2 is not configured or the Serving Cell operates on FR1, this field indicates whether power backoff is applied due to power management (as allowed by P-MPRc as specified in TS 38.101-1, TS 38.101-2, and TS 38.101-3). The MAC entity shall set the P field to 1 if the corresponding P_CMAX,f,c field would have had a different value if no power backoff due to power management had been applied;
• P_CMAX,f,c: This field indicates the P_CMAX,f,c (as specified in TS 38.213) used for calculation of the preceding PH field. The reported P_CMAX,f,c and the corresponding nominal UE transmit power levels are shown in Table 6.1.3.8-2 (the corresponding measured values in dBm are specified in TS 38.133);
• MPE: If mpe-Reporting-FR2 is configured, and the Serving Cell operates on FR2, and if the P field is set to 1, this field indicates the applied power backoff to meet MPE requirements, as specified in TS 38.101-2. This field indicates an index to Table 6.1.3.8-3 and the corresponding measured values of P-MPR levels in dB are specified in TS 38.133. The length of the field is 2 bits. If mpe-Reporting-FR2 is not configured, or if the Serving Cell operates on FR1, or if the P field is set to 0, R bits or DPC is present instead;
• DPC: If dpc-Reporting-FR1 is configured, and the Serving Cell operates on FR1, this field indicates the ΔP_PowerClass, as specified in TS 38.101-1 and TS 38.101-3. This field indicates an index to Table 6.1.3.8-4 and the corresponding measured values of DPC levels in dB are specified in TS 38.133, the DPC field is set to 0 if the criteria to report DPC is not met. The length of the field is 2 bits. If the Serving Cell operates on FR2, R bits or MPE is present instead.

The Multiple Entry PHR MAC CE is identified by a MAC subheader with LCID as specified in Table 6.2.1-2. It has a variable size, and includes the bitmap, a Type 2 PH field and an octet containing the associated P_CMAX,f,c field (if reported) for SpCell of the other MAC entity, a Type 1 PH field and an octet containing the associated P_CMAX,f,c field (if reported) for the PCell. It further includes, in ascending order based on the ServCellIndex, one or multiple of Type X PH fields and octets containing the associated P_CMAX,f,c fields (if reported) for Serving Cells other than PCell indicated in the bitmap. X is either 1 or 3 according to TS 38.213 and TS 36.213. The presence of Type 2 PH field for SpCell of the other MAC entity is configured by phr-Type2OtherCell with value true. A single octet bitmap is used for indicating the presence of PH per Serving Cell when the highest ServCellIndex of Serving Cell with configured uplink is less than 8, otherwise four octets are used. The MAC entity determines whether PH value for an activated Serving Cell is based on real transmission or a reference format by considering the configured grant(s) and downlink control information which has been received until and including the PDCCH occasion in which the first UL grant for a new transmission that can accommodate the MAC CE for PHR as a result of LCP as defined in clause 5.4.3.1 is received since a PHR has been triggered if the PHR MAC CE is reported on an uplink grant received on the PDCCH or until the first uplink symbol of PUSCH transmission minus PUSCH preparation time as defined in clause 7.7 of TS 38.213 if the PHR MAC CE is reported on a configured grant. For a band combination in which the UE does not support dynamic power sharing, the UE may omit the octets containing Power Headroom field and P_CMAX,f,c field for Serving Cells in the other MAC entity except for the PCell in the other MAC entity and the reported values of Power Headroom and P_CMAX,f,c for the PCell are up to UE implementation. The PHR MAC CEs are defined as follows:

• C_i: This field indicates the presence of a PH field for the Serving Cell with ServCellIndex i as specified in TS 38.331. The C_i field set to 1 indicates that a PH field for the Serving Cell with ServCellIndex i is reported. The C_i field set to 0 indicates that a PH field for the Serving Cell with ServCellIndex i is not reported;
• R: Reserved bit, set to 0;
• DPC_BC: If dpc-Reporting-FR1 is configured, this field indicates the ΔP_{PowerClass, CA}/ΔP_{PowerClass, EN-DC}/ΔP_{PowerClass, NR-DC}, as specified in TS 38.101-1 and TS 38.101-3, this field set to 0 indicates the delta power class for band combination is 0dB, this field set to 1 indicates the delta power class for band combination is same or larger than 3 dB. Otherwise, R bit is present, set to 0;
• V: This field indicates if the PH value is based on a real transmission or a reference format. For Type 1 PH, the V field set to 0 indicates real transmission on PUSCH and the V field set to 1 indicates that a PUSCH reference format is used. For Type 2 PH, the V field set to 0 indicates real transmission on PUCCH and the V field set to 1 indicates that a PUCCH reference format is used. For Type 3 PH, the V field set to 0 indicates real transmission on SRS and the V field set to 1 indicates that an SRS reference format is used. Furthermore, for Type 1, Type 2, and Type 3 PH, the V field set to 0 indicates the presence of the octet containing the associated P_CMAX,f,c field and the MPE or DPC field, and the V field set to 1 indicates that the octet containing the associated P_CMAX,f,c field and the MPE or DPC field is omitted;
• Power Headroom (PH): This field indicates the power headroom level. The length of the field is 6 bits. The reported PH and the corresponding power headroom levels are shown in Table 6.1.3.8-1 (the corresponding measured values in dB for the NR Serving Cell are specified in TS 38.133 while the corresponding measured values in dB for the E-UTRA Serving Cell are specified in TS 36.133);
• P: If mpe-Reporting-FR2 is configured and the Serving Cell operates on FR2, the MAC entity shall set this field to 0 if the applied P-MPR value, to meet MPE requirements, as specified in TS 38.101-2, is less than P-MPR_00 as specified in TS 38.133 and to 1 otherwise. If mpe-Reporting-FR2 is not configured or the Serving Cell operates on FR1, this field indicates whether power backoff is applied due to power management (as allowed by P-MPRc as specified in TS 38.101-1, TS 38.101-2, and TS 38.101-3). The MAC entity shall set the P field to 1 if the corresponding P_CMAX,f,c field would have had a different value if no power backoff due to power management had been applied;
• P_CMAX,f,c: If present, this field indicates the P_CMAX,f,c (as specified in TS 38.213) for the NR Serving Cell and the P_CMAX,c or P̃_CMAX,c (as specified in TS 36.213) for the E-UTRA Serving Cell used for calculation of the preceding PH field. The reported P_CMAX,f,c and the corresponding nominal UE transmit power levels are shown in Table 6.1.3.8-2 (the corresponding measured values in dBm for the NR Serving Cell are specified in TS 38.133 while the corresponding measured values in dBm for the E-UTRA Serving Cell are specified in TS 36.133);
• MPE: If mpe-Reporting-FR2 is configured, and the Serving Cell operates on FR2, and if the P field is set to 1, this field indicates the applied power backoff to meet MPE requirements, as specified in TS 38.101-2. This field indicates an index to Table 6.1.3.8-3 and the corresponding measured values of P-MPR levels in dB are specified in TS 38.133. The length of the field is 2 bits. If mpe-Reporting-FR2 is not configured, or if the Serving Cell operates on FR1, or if the P field is set to 0, R bits or DPC is present instead.
• DPC: If dpc-Reporting-FR1 is configured, and the Serving Cell operates on FR1, this field indicates the ΔP_PowerClass, as specified in TS 38.101-1 and TS 38.101-3. This field indicates an index to Table 6.1.3.8-4 and the corresponding measured values of DPC levels in dB are specified in TS 38.133, the DPC field is set to 0 if the criteria to report DPC is not met. The length of the field is 2 bits. If the Serving Cell operates on FR2, R bits or MPE is present instead.

The SCell Activation/Deactivation MAC CE of one octet is identified by a MAC subheader with LCID as specified in Table 6.2.1-1. It has a fixed size and consists of a single octet containing seven C-fields and one R-field. The SCell Activation/Deactivation MAC CE with one octet is defined as follows (Figure 6.1.3.10-1). The SCell Activation/Deactivation MAC CE of four octets is identified by a MAC subheader with LCID as specified in Table 6.2.1-1. It has a fixed size and consists of four octets containing 31 C-fields and one R-field. The SCell Activation/Deactivation MAC CE of four octets is defined as follows (Figure 6.1.3.10-2).

• C_i: If there is an SCell configured for the MAC entity with SCellIndex i as specified in TS 38.331, this field indicates the activation/deactivation status of the SCell with SCellIndex i, else the MAC entity shall ignore the C_i field. The C_i field is set to 1 to indicate that the SCell with SCellIndex i shall be activated. The C_i field is set to 0 to indicate that the SCell with SCellIndex i shall be deactivated;
• R: Reserved bit, set to 0.