Terminal positioning method and baseband unit

1. A terminal positioning method, wherein the method is applied to a baseband unit (BBU) in an indoor distributed NodeB system, and the method comprises:

receiving an uplink positioning signal forwarded by multiple remote radio units (RRUs), wherein the uplink positioning signal is sent by a to-be-positioned terminal to the multiple RRUs;

selecting, from the multiple RRUs, at least two RRUs as target RRUs according to the uplink positioning signal, and a channel correlation coefficient, wherein selecting comprises:

obtaining channel state information of a channel from the to-be-positioned terminal to the multiple RRUs according to the uplink positioning signal; and

in response to determining, according to the channel state information, that a channel correlation coefficient between channel state information of every two of the at least two RRUs is less than a third preset value, selecting the at least two RRUs as the target RRUs; and

respectively obtaining signal angles of arrival corresponding to the target RRUs, and determining a location of the to-be-positioned terminal according to the signal angles of arrival, locations of the target RRUs, and a preset algorithm.

2. The method according to claim 1 , wherein the respectively obtaining signal angles of arrival corresponding to the target RRUs, and determining the location of the to-be-positioned terminal according to the signal angles of arrival, locations of the target RRUs, and the preset algorithm comprises:

calculating the signal angles of arrival corresponding to the target RRUs according to the following manner:

α= ar cos((λθ)/(2π d )),

wherein α represents the signal angles of arrival corresponding to the target RRUs, λ represents a wavelength of a radio signal, θ represents a phase difference between signals received by adjacent antenna array elements, d represents a distance between the antenna array elements, and π is a circumference ratio; and

calculating the location of the to-be-positioned terminal according to the calculated signal angles of arrival, the locations of the target RRUs, and the preset algorithm.

3. A baseband unit in an indoor distributed NodeB system, wherein the baseband unit comprises:

a receiver, configured to receive an uplink positioning signal forwarded by multiple remote radio units (RRUs), wherein the uplink positioning signal is sent by a to-be-positioned terminal to the multiple RRUs;

a non-transitory memory storage comprising instructions; and

one or more hardware processors in communication with the memory storage, wherein the one or more hardware processors execute the instructions to:

select, from the multiple RRUs, at least two RRUs as target RRUs according to the uplink positioning signal and a channel correlation coefficient, wherein the one or more hardware processors execute the instructions to select the at least two RRUs as the target RRUs comprises the one or more hardware processors execute the instructions to:

obtain channel state information of a channel from the to-be-positioned terminal to the multiple RRUs according to the uplink positioning signal; and

in response to determining, according to the channel state information, that a channel correlation coefficient between channel state information of every two of the at least two RRUs is less than a third preset value, select the at least two RRUs as the target RRUs; and

respectively obtain signal angles of arrival corresponding to the target RRUs, and determine a location of the to-be-positioned terminal according to the signal angles of arrival, locations of the target RRUs, and a preset algorithm.

4. The baseband unit according to claim 3 , wherein the one or more hardware processors execute the instructions to:

calculate the signal angles of arrival corresponding to the target RRUs according to the following manner:

α= ar cos((λθ)/(2π d )),

wherein α represents the signal angles of arrival corresponding to the target RRUs, λ represents a wavelength of a radio signal, θ represents a phase difference between signals received by adjacent antenna array elements, d represents a distance between the antenna array elements, and π is a circumference ratio; and

calculate the location of the to-be-positioned terminal according to the signal angles of arrival, the locations of the target RRUs, and the preset algorithm.

5. A baseband unit, comprising a memory, a transceiver, a processor, and a bus system, wherein

the memory is configured to store a program;

the processor is configured to execute the program in the memory, to specifically perform the following steps:

controlling the transceiver to receive an uplink positioning signal forwarded by multiple remote radio units (RRUs), wherein the uplink positioning signal is sent by a to-be-positioned terminal to the multiple RRUs;

selecting, from the multiple RRUs, at least two RRUs as target RRUs according to the uplink positioning signal and a channel correlation coefficient, wherein selecting comprises:

obtaining channel state information of a channel from the to-be-positioned terminal to the multiple RRUs according to the uplink positioning signal; and

in response to determining, according to the channel state information, that a channel correlation coefficient between channel state information of every two of the at least two RRUs is less than a third preset value, selecting the at least two RRUs as the target RRUs; and

respectively obtaining signal angles of arrival corresponding to the target RRUs, and determining a location of the to-be-positioned terminal according to the signal angles of arrival, locations of the target RRUs, and a preset algorithm; and

the bus system is configured to communicatively couple the memory, the transceiver, and the processor with each other.

6. The baseband unit according to claim 5 , wherein the respectively obtaining signal angles of arrival corresponding to the target RRUs, and determining the location of the to-be-positioned terminal according to the signal angles of arrival, locations of the target RRUs, and the preset algorithm comprises:

calculate the signal angles of arrival corresponding to the target RRUs according to the following manner:

α= ar cos((λθ)/(2π d )),

wherein α represents the signal angles of arrival corresponding to the target RRUs, λ represents a wavelength of a radio signal, θ represents a phase difference between signals received by adjacent antenna array elements, d represents a distance between the antenna array elements, and π is a circumference ratio; and

calculate the location of the to-be-positioned terminal according to the signal angles of arrival, the locations of the target RRUs, and the preset algorithm.