Sounding reference signal for uplink-based multi-cell measurement
Aspects of the present application provide methods and devices in a communication network that aid in implementing sounding reference signal (SRS) measurement by multiple cells (i.e. serving cells and non-serving cells, also known as “neighbor cells”) as well as NR LMUs. This enhanced SRS measurement based on multiple cell and/or NR LMU measurements may facilitate more beneficial usages such as UL-based positioning and UL-based mobility.
1 . A method comprising:
receiving, by a user equipment (UE) from a serving cell, downlink (DL) reference signal (RS) configuration information for configuring the UE to receive a first DL RS from a non-serving cell, wherein the non-serving cell is a cell other than any cell that serves the UE, and wherein the DL RS configuration information for configuring the UE to receive the first DL RS from the non-serving cell indicates:
a Synchronization Signal/Physical Broadcast Channel (SS/PBCH) block frequency location;
an SS/PBCH block subcarrier spacing;
an SS/PBCH block index;
a physical cell identifier (PCID) of a cell transmitting an SS/PBCH block; and
a timing reference to obtain a time location of the SS/PBCH block;
receiving, by the UE from the non-serving cell, the first DL RS; and
transmitting, by the UE, a sounding reference signal (SRS), the SRS transmitted in accordance with a transmission parameter, the transmission parameter including a transmit power obtained based on a pathloss estimated from the first DL RS received from the non-serving cell.
2 . The method of claim 1 , wherein the first DL RS is the SS/PBCH block.
3 . The method of claim 1 , wherein the DL RS configuration information further configures the UE to receive a second DL RS from the non-serving cell, and the transmission parameter further includes a spatial domain transmission filter obtained based on the second DL RS.
4 . The method of claim 3 , wherein the transmitting, by the UE, the SRS comprises transmitting the SRS in accordance with the spatial domain transmission filter, the spatial domain transmission filter being the same as a spatial domain filter used for receiving the second DL RS.
5 . The method of claim 4 , wherein the DL RS configuration information is received using higher layer signaling, and the higher layer signaling comprises a higher layer parameter indicating the second DL RS used for obtaining the spatial domain transmission filter.
6 . The method of claim 3 , wherein the first DL RS is same as the second DL RS.
7 . The method of claim 3 , wherein the second DL RS is an SS/PBCH or a channel state information reference signal (CSI-RS).
8 . The method of claim 1 , wherein the indication further indicates:
a SS/PBCH block measurement timing configuration (SMTC) window indication including both periodicity and offset.
9 . The method of claim 1 , wherein the SS/PBCH block frequency location is a New Radio Absolute Radio Frequency Channel Number (NR-ARFCN) value.
10 . The method of claim 1 , wherein the timing reference is a timing of a primary cell (Pcell).
11 . The method of claim 1 , wherein the DL RS configuration information is received using higher layer signaling, and the higher layer signaling comprises a higher layer parameter indicating the first DL RS used for estimating the pathloss.
12 . The method of claim 1 , wherein the transmitting, by the UE, the SRS comprises:
transmitting the SRS using an SRS resource of an SRS resource set in accordance with the transmission parameter obtained based on the first DL RS; or transmitting the SRS using all SRS resources of the SRS resource set in accordance with the transmission parameter obtained based on the first DL RS.
13 . The method of claim 1 , wherein the non-serving cell is a neighbor cell.
14 . A user equipment (UE) comprising:
at least one processor;
a non-transitory computer-readable storage medium having stored thereon, computer-executable instructions that when executed by the at least one processor cause the UE to:
receive, from a serving cell, downlink (DL) reference signal (RS) configuration information for configuring the UE to receive a first DL RS from a non-serving cell, wherein the non-serving cell is a cell other than any cell that serves the UE, and wherein the DL RS configuration information for configuring the UE to receive the first DL RS from the non-serving cell indicates:
a Synchronization Signal/Physical Broadcast Channel (SS/PBCH) block frequency location;
an SS/PBCH block subcarrier spacing;
an SS/PBCH block index;
a physical cell identifier (PCID) of a cell transmitting an SS/PBCH block; and
a timing reference to obtain a time location of the SS/PBCH block;
receive, from the non-serving cell, the first DL RS; and
transmit, a sounding reference signal (SRS), the SRS transmitted in accordance with a transmission parameter, the transmission parameter including a transmit power based on a pathloss estimated from the first DL RS received from the non-serving cell.
15 . The UE of claim 14 , wherein the first DL RS is the SS/PBCH block.
16 . The UE of claim 14 , wherein the DL RS configuration information further configures the UE to receive a second DL RS from the non-serving cell, and the transmission parameter further includes a spatial domain transmission filter based on the second DL RS.
17 . The UE of claim 16 , wherein the computer-executable instructions, that when executed by the at least one processor cause the UE to transmit the SRS, include computer-executable instructions to cause the UE to:
transmit the SRS in accordance with the spatial domain transmission filter, the spatial domain transmission filter being the same as a spatial domain filter used for receiving the second DL RS.
18 . The UE of claim 17 , wherein the DL RS configuration information is received using higher layer signaling, and the higher layer signaling comprises a higher layer parameter indicating the second DL RS used for obtaining the spatial domain transmission filter.
19 . The UE of claim 16 , wherein the first DL RS is same as the second DL RS.
20 . The UE of claim 16 , wherein the second DL RS is an SS/PBCH or a channel state information reference signal (CSI-RS).
21 . The UE of claim 15 , wherein the computer-executable instructions, that when executed by the at least one processor cause the UE to transmit the SRS, include computer-executable instructions to cause the UE to:
transmit the SRS using an SRS resource of an SRS resource set in accordance with the transmission parameter based on the first DL RS; or transmit the SRS using all SRS resources of the SRS resource set in accordance with the transmission parameter based on the first DL RS.
22 . The UE of claim 14 , wherein the SS/PBCH block frequency location is a New Radio Absolute Radio Frequency Channel Number (NR-ARFCN) value.
23 . The UE of claim 14 , wherein the timing reference is a timing of a primary cell (Pcell).
24 . The UE of claim 14 , wherein the DL RS configuration information is received using higher layer signaling, and the higher layer signaling comprises a higher layer parameter indicating the first DL RS used for estimating the pathloss.
25 . The UE of claim 14 , wherein the non-serving cell is a neighbor cell.
26 . A method comprising:
receiving, by a user equipment (UE), higher layer signaling including a configuration message configuring a first Synchronization Signal/Physical Broadcast Channel (SS/PBCH) block for pathloss estimation by the UE, wherein the configuration message in the higher layer signaling indicates:
an SS/PBCH block frequency location,
an SS/PBCH block subcarrier spacing,
an SS/PBCH block index,
a physical cell identifier (PCID) of a serving cell transmitting the first SS/PBCH block, and
a timing reference to obtain a time location of the first SS/PBCH block;
after the receiving the higher layer signaling and in response to the UE failing to detect the first SS/PBCH block from the serving cell:
receiving, by the UE, a second SS/PBCH block from the serving cell, the second SS/PBCH block used for obtaining a Master Information Block (MIB), the second SS/PBCH block being different from the first SS/PBCH block;
estimating, by the UE, pathloss from the second SS/PBCH block; and
transmitting, by the UE, a sounding reference signal (SRS) to a non-serving cell using a transmit power based on the pathloss estimated from the second SS/PBCH block used for obtaining the MIB.
27 . The method of claim 26 , wherein the first SS/PBCH block and the second SS/PBCH block are in a same carrier frequency.
28 . A user equipment (UE) comprising:
at least one processor;
a computer-readable storage medium having stored thereon, computer-executable instructions that when executed by the at least one processor cause the UE to perform operations including:
receiving higher layer signaling including a configuration message configuring a first Synchronization Signal/Physical Broadcast Channel (SS/PBCH) block for pathloss estimation by the UE, wherein the configuration message in the higher layer signaling indicates:
an SS/PBCH block frequency location,
an SS/PBCH block subcarrier spacing,
an SS/PBCH block index,
a physical cell identifier (PCID) of a serving cell transmitting the first SS/PBCH block, and
a timing reference to obtain a time location of the first SS/PBCH block;
after the receiving the higher layer signaling and in response to failing to detect the first SS/PBCH block from the serving cell:
receiving a second SS/PBCH block from the serving cell, the second SS/PBCH block used for obtaining a Master Information Block (MIB), the second SS/PBCH block being different from the first SS/PBCH block;
estimating pathloss from the second SS/PBCH block; and
transmitting a sounding reference signal (SRS) to a non-serving cell using a transmit power based on the pathloss estimated from the second SS/PBCH block used for obtaining the MIB.