SSS transmit power is determined as the linear average over the power contributions (in [W]) of the resource elements that carry secondary synchronization signals within the secondary synchronization signal (SSS) bandwidth. For downlink reference signal transmit power determination the secondary synchronization signal according TS 38.211 can be used. For frequency range 1, the reference point for the downlink reference signal power measurement shall be the transmit antenna connector.

The UL Relative Time of Arrival (_TUL-RTOA) is the beginning of subframe i containing SRS received in Reception Point (RP) [18] j, relative to the RTOA Reference Time [16]. The UL RTOA reference time is defined as T₀ + t_SRS, where

• T₀ is the nominal beginning time of SFN 0 provided by SFN Initialization Time (TS 38.455)
• t_SRS = (10n_f + n_sf)× 10), where n_f and n_sf are the system frame number and the subframe number of the SRS, respectively.

Multiple SRS resources can be used to determine the beginning of one subframe containing SRS received at a RP. The reference point for T_UL-RTOA shall be:

• for type 1-C base station TS 38.104: the Rx antenna connector,
• for type 1-O or 2-O base station TS 38.104: the Rx antenna (i.e. the centre location of the radiating region of the Rx antenna),
• for type 1-H base station TS 38.104: the Rx Transceiver Array Boundary connector.

The gNB Rx - Tx time difference is defined as T - T_gNB-TX

Where:

• T_gNB-RX is the Transmission and Reception Point (TRP) [18] received timing of uplink subframe #i containing SRS associated with UE, defined by the first detected path in time.
• T_gNB-TX is the TRP transmit timing of downlink subframe #j that is closest in time to the subframe #i received from the UE.

Multiple SRS resources can be used to determine the start of one subframe containing SRS.

The reference point for T_gNB-RX shall be:

• for type 1-C base station TS 38.104: the Rx antenna connector,
• for type 1-O or 2-O base station TS 38.104: the Rx antenna (i.e. the centre location of the radiating region of the Rx antenna),
• for type 1-H base station TS 38.104: the Rx Transceiver Array Boundary connector.

The reference point for T_gNB-TX shall be:

• for type 1-C base station TS 38.104: the Tx antenna connector,
• for type 1-O or 2-O base station TS 38.104: the Tx antenna (i.e. the centre location of the radiating region of the Tx antenna),
• for type 1-H base station TS 38.104: the Tx Transceiver Array Boundary connector.

In NTN, the gNB Rx - Tx time difference at the uplink time synchronization reference point [5] is reported.

UL Angle of Arrival (UL AoA) is defined as the estimated azimuth angle (A-AoA) and vertical angle (Z-AoA) of a UE with respect to a reference direction, wherein the reference direction is defined:

• In the global coordinate system (GCS), wherein estimated azimuth angle is measured relative to geographical North and is positive in a counter-clockwise direction and estimated vertical angle is measured relative to zenith and positive to horizontal direction
• In the local coordinate system (LCS), wherein estimated azimuth angle is measured relative to x-axis of LCS and positive in a counter-clockwise direction and estimated vertical angle is measured relative to z-axis of LCS and positive to x-y plane direction. The bearing, downtilt and slant angles of LCS are defined according to TS 38.901.

The UL-AoA is determined at the gNB antenna for an UL channel corresponding to this UE.

UL SRS reference signal received power (UL SRS-RSRP) is defined as linear average of the power contributions (in [W]) of the resource elements carrying sounding reference signals (SRS). UL SRS-RSRP shall be measured over the configured resource elements within the considered measurement frequency bandwidth in the configured measurement time occasions. The reference point for UL SRS-RSRP shall be:

• for type 1-C base station TS 38.104: the Rx antenna connector,
• for type 1-O or 2-O base station TS 38.104: based on the combined signal from antenna elements corresponding to a given receiver branch,
• for type 1-H base station TS 38.104: the Rx Transceiver Array Boundary connector.

For frequency range 1 and 2, if receiver diversity is in use by the gNB, the reported UL SRS-RSRP value shall not be lower than the corresponding UL SRS-RSRP of any of the individual receiver branches.

UL SRS reference signal received path power (UL SRS-RSRPP) is defined as the power of the linear average of the channel response at the i-th path delay of the resource elements that carry the received UL SRS signal configured for the measurement, where UL SRS-RSRPP for 1st path delay is the power contribution corresponding to the first detected path in time. The reference point for UL SRS-RSRPP shall be:

• for type 1-C base station TS 38.104: the Rx antenna connector,
• for type 1-O or 2-O base station TS 38.104: based on the combined signal from antenna elements corresponding to a given receiver branch
• for type 1-H base station TS 38.104: the Rx Transceiver Array Boundary connector.

For frequency range 1 and 2, if receiver diversity is in use by the gNB for UL SRS-RSRPP measurements:

• The reported UL SRS-RSRPP value for the first and additional paths shall be provided for the same receiver branch(es) as applied for UL SRS-RSRP measurements, or
• The reported UL SRS-RSRPP value for the first path shall not be lower than the corresponding UL SRS-RSRPP for the first path of any of the individual receiver branches and the reported UL SRS-RSRPP for the additional paths shall be provided for the same receiver branch(es) as applied UL SRS-RSRPP for the first path.

Timing advance (T_ADV) is defined as the time difference T_ADV = (T_NB-RXg - T_gNB-TX), Where: T_gNB-RX is the Transmission and Reception Point (TRP) [18] received timing of uplink subframe #i containing PRACH transmitted from UE, defined by the first detected path in time. T_gNB-TX is the TRP transmit timing of downlink subframe #j that is closest in time to the subframe #i received from the UE. The detected PRACH is used to determine the start of one subframe containing that PRACH. The reference point for T_gNB-RX shall be:

• for type 1-C base station TS 38.104: the Rx antenna connector,
• for type 1-O or 2-O base station TS 38.104: the Rx antenna (i.e. the centre location of the radiating region of the Rx antenna),
• for type 1-H base station TS 38.104: the Rx Transceiver Array Boundary connector.

The reference point for TgNB-TX shall be:

• for type 1-C base station TS 38.104: the Tx antenna connector,
• for type 1-O or 2-O base station TS 38.104: the Tx antenna (i.e. the centre location of the radiating region of the Tx antenna),
• for type 1-H base station TS 38.104: the Tx Transceiver Array Boundary connector.

UL reference signal carrier phase (RSCP) is defined as the phase of the channel response at the 1st path delay derived from the resource elements carrying sounding reference signals (SRS) configured for the measurement. UL RSCP is associated with the center frequency of the transmission bandwidth of the SRS for positioning purposes configured for the measurement. The reference point for UL RSCP shall be:

• for type 1-C base station TS 38.104: the Rx antenna connector,
• for type 1-O or 2-O base station TS 38.104: the Rx antenna (i.e., the centre location of the radiating region of the Rx antenna),
• for type 1-H base station TS 38.104: the Rx Transceiver Array Boundary connector.