SL positioning power control
Methods and apparatuses for sidelink (SL) positioning power control in a wireless communication system. A method of operating a user equipment (UE) includes determining a power for a SL positioning reference signal (PRS) in a transmission occasion i based on P SL-PRS (i)=min(P CMAX ,P MAX,CBR ,min(P SL-PRS,D (i),P SL-PRS,SL (i))). P CMAX is a configured maximum output power of the UE. P MAX,CBR is related to a priority level of the SL PRS and a channel busy ratio (CBR) range for a CBR measured in slot i−N, where N is a congestion control processing time. P SL-PRS,D (i) is a component for downlink (DL) pathloss based power control for the SL PRS. P SL-PRS,SL (i) is a component for SL pathloss based power control for the SL PRS. The method further includes transmitting the SL PRS in the transmission occasion i with the power P SL-PRS (i).
1 . A user equipment (UE) comprising:
a processor configured to determine a power for a sidelink (SL) positioning reference signal (PRS) in a transmission occasion i based on P SL-PRS (i)=min(P CMAX ,P MAX,CBR ,min(P SL-PRS,D (i),P SL-PRS,SL (i))), wherein:
P CMAX is a configured maximum output power of the UE,
P MAX,CBR is related to a priority level of the SL PRS and a channel busy ratio (CBR) range for a CBR measured in slot i−N, where N is a congestion control processing time,
P SL-PRS,D (i) is a component for downlink (DL) pathloss based power control for the SL PRS, and
P SL-PRS,SL (i) is a component for SL pathloss based power control for the SL PRS; and
a transceiver operably coupled to the processor, the transceiver configured to transmit the SL PRS in the transmission occasion i with the power P SL-PRS (i) to a second UE.
2 . The UE of claim 1 , wherein the SL PRS is associated with one antenna port.
3 . The UE of claim 1 , wherein:
the transceiver further configured to receive information related to a P O,D value for the DL pathloss based power control,
the processor is further configured to calculate the component for the DL pathloss based power control based on
P
SL
-
PRS
,
D
(
i
)
=
P
O
,
D
+
10
log
10
(
2
μ
·
M
RB
SL
-
PRS
(
i
)
)
+
α
D
·
PL
D
,
μ is a sub-carrier spacing configuration of the SL PRS,
M
RB
SL
-
PRS
(
i
)
is a number of resource blocks for the SL PRS in the transmission occasion i,
α D is an alpha value for DL pathloss based power control for the SL PRS, and
PL D is a downlink pathloss.
4 . The UE of claim 3 , wherein:
the UE operates in a resource pool shared with SL data,
the P O,D is for the DL pathloss based power control configured for a physical sidelink shared channel (PSSCH) or a physical sidelink control channel (PSCCH), and
the α D is for the DL pathloss based power control configured for the PSSCH or PSCCH.
5 . The UE of claim 3 , wherein:
the UE operates in a resource pool dedicated for the SL PRS,
the P O,D is for the DL pathloss based power control configured for the SL PRS, and
the α D is for the DL pathloss based power control configured for the SL PRS.
6 . The UE of claim 3 , wherein, when a value for α D is not provided, the processor is further configured to set α D =1.
7 . The UE of claim 1 , wherein, when a value for P O,D is not provided, the processor is further configured to calculate the component for the DL pathloss based power control based on P SL-PRS,D (i)=min(P CMAX ,P MAX,CBR ).
8 . The UE of claim 1 , wherein:
the transceiver further configured to receive information related to a P O,SL value for the SL pathloss based power control,
the processor is further configured to calculate the component for SL pathloss based power control for the SL PRS based on
P
SL
-
PRS
,
SL
(
i
)
=
P
O
,
SL
+
10
log
10
(
2
μ
·
M
RB
SL
-
PRS
(
i
)
)
+
α
SL
·
PL
SL
,
μ is a sub-carrier spacing configuration of the SL PRS,
M
RB
SL
-
PRS
(
i
)
is a number of resource blocks for the SL PRS transmission occasion i,
α SL is an alpha value for the SL pathloss based power control for the SL PRS, and
PL SL is a SL pathloss.
9 . The UE of claim 8 , wherein:
the UE operates in a resource pool shared with SL data,
the P O,SL is the SL pathloss based power control configured for a physical sidelink shared channel (PSSCH) or a physical sidelink control channel (PSCCH), and
the α SL is for the SL pathloss based power control configured for the PSSCH or PSCCH.
10 . The UE of claim 8 , wherein:
the transceiver is further configured to receive information related to a higher layer filtered reference signal received power (RSRP) of the SL PRS from the second UE,
wherein, the higher layer filtered RSRP is across SL PRS transmission occasions using a filter configuration provided by a parameter sl-FilterCoefficient, and
the processor is further configured to:
calculate a reference signal power based on a SL PRS transmit power per resource element (RE), filtered across SL PRS transmission occasions using a filter configuration provided by the parameter sl-FilterCoefficient, and
calculate the SL pathloss based on PL SL =the reference signal power−the higher layer filtered RSRP.
11 . A method of operating a user equipment (UE), the method comprising:
determining a power for a sidelink (SL) positioning reference signal (PRS) in a transmission occasion i based on P SL-PRS (i)=min(P CMAX ,P MAX,CBR ,min(P SL-PRS,D (i),P SL-PRS,SL (i))), wherein:
P CMAX is a configured maximum output power of the UE,
P MAX,CBR is related to a priority level of the SL PRS and a channel busy ratio (CBR) range for a CBR measured in slot i−N, where N is a congestion control processing time,
P SL-PRS,D (i) is a component for downlink (DL) pathloss based power control for the SL PRS, and
P SL-PRS,SL (i) is a component for SL pathloss based power control for the SL PRS; and
transmitting the SL PRS in the transmission occasion i with the power P SL-PRS (i) to a second UE.
12 . The method of claim 11 , wherein the SL PRS is associated with one antenna port.
13 . The method of claim 11 , further comprising:
receiving information related to a P O,D value for the DL pathloss based power control, and
calculating the component for the DL pathloss based power control based on
P
SL
-
PRS
,
D
(
i
)
=
P
O
,
D
+
10
log
10
(
2
μ
·
M
RB
SL
-
PRS
(
i
)
)
+
α
D
·
PL
D
,
wherein:
μ is a sub-carrier spacing configuration of the SL PRS,
M
RB
SL
-
PRS
(
i
)
is a number of resource blocks for the SL PRS in the transmission occasion i,
α D is an alpha value for DL pathloss based power control for the SL PRS, and
PL D is a downlink pathloss.
14 . The method of claim 13 , wherein:
the UE operates in a resource pool shared with SL data,
the P O,D is for the DL pathloss based power control configured for a physical sidelink shared channel (PSSCH) or a physical sidelink control channel (PSCCH), and
the α D is for the DL pathloss based power control configured for the PSSCH or PSCCH.
15 . The method of claim 13 , wherein:
the UE operates in a resource pool dedicated for the SL PRS,
the P O,D is for the DL pathloss based power control configured for the SL PRS, and
the α D is for the DL pathloss based power control configured for the SL PRS.
16 . The method of claim 13 , further comprising, when a value for α D is not provided, setting α D =1.
17 . The method of claim 11 , further comprising, when a value for P O,D is not provided, calculating the component for the DL pathloss based power control based on P SL-PRS,D (i)=min(P CMAX ,P MAX,CBR ).
18 . The method of claim 11 , further comprising:
receiving information related to a P O,SL value for the SL pathloss based power control, and
calculating the component for SL pathloss based power control for the SL PRS based on
P
SL
-
PRS
,
SL
(
i
)
=
P
O
,
SL
+
10
log
10
(
2
μ
·
M
RB
SL
-
PRS
(
i
)
)
+
α
SL
·
PL
SL
,
wherein:
μ is a sub-carrier spacing configuration of the SL PRS,
M
RB
SL
-
PRS
(
i
)
is a number of resource blocks for the SL PRS transmission occasion i,
α SL is an alpha value for the SL pathloss based power control for the SL PRS, and
PL SL is a SL pathloss.
19 . The method of claim 18 , wherein:
the UE operates in a resource pool shared with SL data,
the P O,SL is for the SL pathloss based power control configured for a physical sidelink shared channel (PSSCH) or a physical sidelink control channel (PSCCH), and
the α SL is for the SL pathloss based power control configured for the PSSCH or PSCCH.
20 . The method of claim 18 , further comprising:
receiving information related to a higher layer filtered reference signal received power (RSRP) of the SL PRS from the second UE, wherein the higher layer filtered RSRP is across SL PRS transmission occasions using a filter configuration provided by a parameter sl-FilterCoefficient,
calculating a reference signal power based on a SL PRS transmit per resource element (RE) filtered across SL PRS transmission occasions using a filter configuration provided by the parameter sl-FilterCoefficient, and
calculating a SL pathloss based on PL SL =the reference signal power−the higher layer filtered RSRP.