Positioning method, positioning server, terminal and base station

1. A positioning method comprising:

sending, from a positioning server and to a terminal, positioning capability information that the terminal supports performing a positioning measurement according to a plurality of radio access techniques (RATs);

determining, by the positioning server, a first RAT whose load is the lightest among the plurality of RATs;

sending allocation information from the positioning server and to a base station, where the allocation information

a) is part of a message requesting the base station report a configuration of a positioning reference signal (PRS) or a dedicated message sent before the message requesting the base station report the PRS configuration, and

b) instructs the base station to transmit the PRS to the terminal through the first RAT, and adjust the configuration of the PRS by reducing a measured value of a reference signal of a cell pair when the measured value is greater than a threshold comprising at least one of the following:

i. a reference signal receiving power (RSRP) difference of the cell pair,

ii. a cell-specific reference signal (CRS) signal to noise ratio (SNR) difference of the cell pair,

iii. a PRP difference of the cell pair and a first mapping factor, and

iv. a PRS SNR difference of the cell pair and a second mapping factor,

where the cell pair is identified by cell subset information determined by the terminal;

receiving, by the positioning server, the configuration of the PRS fed back by the base station;

notifying, by the positioning server, the terminal of the configuration of the PRS;

receiving, by the positioning server, a reference signal time difference (RSTD) that is obtained by the terminal through measurement according to the configuration of the PRS; and

determining, by the positioning server, a location of the terminal according to the RSTD.

2. The method according to claim 1 , wherein exchanging the positioning capability information comprises:

carrying, by the positioning server, RAT request information in a message for requesting the terminal to report a capability, wherein the RAT request information is used to request the terminal to report the positioning capability information; and

receiving, by the positioning server, the positioning capability information that is carried by the terminal in the reported capability information.

3. A positioning method comprising:

receiving, by a terminal and from a positioning server, positioning capability information that the terminal supports performing a positioning measurement according to a plurality of radio access techniques (RATs) to enable the positioning server to determine a first RAT whose load is the lightest among the plurality of RATs;

receiving, by the terminal, a configuration of a positioning reference signal (PRS) notified by the positioning server,

wherein the configuration of the PRS is determined by the positioning server according to cell subset information indicating a cell pair whose reference signal measured value difference exceeds a threshold, and instructs a base station to (a) transmit the PRS using the first RAT and (b) adjust the configuration of the PRS to reduce the reference signal measured value difference when it is greater than the threshold, where the threshold comprises at least one of the following:

i. a reference signal receiving power (RSRP) difference of the cell pair,

ii. a cell-specific reference signal (CRS) signal to noise ratio (SNR) difference of the cell pair,

iii. a PRP difference of the cell pair and a first mapping factor, and

iv. a PRS SNR difference of the cell pair and a second mapping factor;

obtaining, by the terminal, a reference signal time difference (RSTD) through measurement according to the configuration of the PRS; and

sending, by the terminal, the RSTD to the positioning server.

4. The method according to claim 3 , wherein receiving the positioning capability information at the terminal comprises:

receiving RAT request information carried by the positioning server in a message for requesting the terminal to report a capability, wherein the RAT request information requests the terminal report the positioning capability information; and

the method further comprises:

carrying the positioning capability information in capability information sent to the positioning server.

5. A positioning server comprising a transceiver and a processor, wherein

the transceiver is configured to send, to a terminal, positioning capability information that the terminal supports performing a positioning measurement according to a plurality of radio access techniques (RATs);

the processor is configured to determine a first RAT whose load is the lightest among the plurality of RATs;

the transceiver is configured to send allocation information to a base station and receive a configuration of a positioning reference signal (PRS) fed back by the base station, where the allocation information is (a) part of a message requesting the base station report the PRS configuration or (b) a dedicated message sent before the message requesting the base station report the PRS configuration,

wherein the allocation information instructs the base station to (a) transmit the PRS to the terminal through the first RAT, and (b) adjust the configuration of the PRS by reducing a measured value of a reference signal of a cell pair when the measured value is greater than a threshold comprising at least one of the following:

i. a reference signal receiving power (RSRP) difference of the cell pair,

ii. a cell-specific reference signal (CRS) signal to noise ratio (SNR) difference of the call pair,

iii. a PRP difference of the call pair and a first mapping factor, and

iv. a PRS SNR difference of the cell pair and a second mapping factor, where the cell pair is identified by cell subset information determined by the terminal;

the transceiver is further configured to notify the terminal of the configuration of the PRS and receive a reference signal time difference (RSTD) that is obtained by the terminal through measurement according to the configuration of the PRS; and

the processor is further configured to determine a location of the terminal according to the RSTD.

6. The positioning server according to claim 5 , wherein the transceiver is further configured to

carry RAT request information in a message for requesting the terminal to report a capability, wherein the RAT request information is used to request the terminal to report the positioning capability information; and

receive the positioning capability information that is carried by the terminal in reported capability information.

7. A terminal comprising:

a transceiver configured to

a) receive, from a positioning server, positioning capability information that the terminal supports performing a positioning measurement according to a plurality of radio access techniques (RATs) to enable the positioning server to determine a first RAT whose load is the lightest among the plurality of RATs;

b) receive a configuration of a positioning reference signal (PRS) notified by the positioning server and RAT request information carried by the positioning server, which is included in a message requesting the terminal report positioning capability information; and

c) send to the positioning server the positioning capability information,

wherein the configuration of the PRS is determined by the positioning server according to cell subset information indicating a cell pair whose reference signal measured value difference exceeds a threshold, and instructs a base station to transmit the PRS using the first RAT, and adjust a configuration of the PRS to reduce the reference signal measured value difference which is greater than the threshold, where the threshold comprises at least one of the following:

i. a threshold of a reference signal receiving power (RSRP) difference of the cell pair,

ii. a threshold of a cell-specific reference signal (CRS) signal to noise ratio (SNR) difference of the cell pair,

iii. a threshold of a PRP difference of the cell pair and a first mapping factor, and

iv. a threshold of a PRS SNR difference of the cell pair and a second mapping factor;

a processor configured to obtain a reference signal time difference (RSTD) through measurement according to the configuration of the PRS; and

the transceiver is further configured to send the RSTD to the positioning server.

8. The terminal according to claim 7 , wherein the transceiver is further configured to

receive RAT request information that is carried by the positioning server in a message for requesting the terminal to report a capability, wherein the RAT request information is used to request the terminal to report the positioning capability information; and

carry the positioning capability information in capability information that is sent to the positioning server.