CN112738850A

CN112738850A - Interference coordination method and device based on UE position

Info

Publication number: CN112738850A
Application number: CN202011540597.0A
Authority: CN
Inventors: 温泉泉
Original assignee: Ruijie Networks Co Ltd
Current assignee: Ruijie Networks Co Ltd
Priority date: 2020-12-23
Filing date: 2020-12-23
Publication date: 2021-04-30

Abstract

The invention provides an interference coordination method and device based on UE position, the method comprises: determining a serving cell and a neighboring cell of the serving cell; receiving Reference Signal Received Power (RSRP) respectively measured by UE belonging to the serving cell and between the UE and the serving cell and the neighbor cell, wherein the RSRP is sent by the UE; determining that the UE is a central UE or an edge UE according to the RSRP between the UE and the serving cell; positioning the edge UE; attributing the edge UE to a UE set corresponding to at least one neighbor cell according to the positioning result of the edge UE, wherein the UE in the UE set is the UE which is expected to generate interference on the attributive neighbor cell; and when the high interference indication is sent to the first adjacent cell, only sending the high interference indication to the UE in the UE set corresponding to the first adjacent cell. The interaction frequency of interface signaling between the base station and the base station can be reduced.

Description

Interference coordination method and device based on UE position

Technical Field

The present invention relates to the field of data communications, and in particular, to a method and an apparatus for interference coordination based on a UE location.

Background

In the cellular mobile communication network constructed by using orthogonal frequency division multiple access (OFDM) and OFDMA as a multiple access method, the fifth generation mobile communication technology 5G can achieve a frequency reuse factor of 1, that is, all cells in the entire system range use the same frequency band to provide services for users in the cell. Due to the limited frequency resources, resources need to be shared among multiple cells to improve the spectrum utilization rate of the resources, and thus co-channel interference among the cells is introduced. Especially for cell edge users, inter-cell interference is one of the most important factors affecting their performance.

The influence of inter-cell interference on system performance has been widely discussed in 5G systems, and 2 techniques for reducing inter-cell interference and improving performance of cell edge users are mainly proposed: the interference between cells is randomized and the interference between cells is eliminated.

Firstly, randomizing interference among cells;

the objective of inter-cell interference randomization is to obtain a randomized interference signal at the receiving end, and this method can bring the interference signal close to white noise, although the energy of the interference signal cannot be reduced, and thus can obtain a processing gain when performing interference suppression. Common methods of interference randomization: scrambling specifically for each cell, wherein signals of each cell are scrambled by adopting different pseudo-random scrambling codes after channel coding and channel interleaving so as to obtain the effect of interference white noise; the specific interleaving of the cells is to perform channel interleaving on signals of each cell by adopting different interleaving patterns after channel coding so as to obtain the effect of interference whitening; and (3) carrying out frequency hopping by adopting different frequency hopping patterns according to the specific frequency hopping of the cells, thereby obtaining the effect of interference white noise.

Secondly, eliminating interference among cells;

the inter-cell interference elimination utilizes the estimation of the first interference signal to eliminate the interference signals of other cells as much as possible during signal detection, thereby obtaining processing gain at a receiving end and improving the performance of the receiving end. A common inter-cell interference cancellation method:

A. spatial interference suppression technology based on multi-antenna receiving terminal

This technique is also known as interference rejection combining, receiving technique. It does not rely on any additional transmit side configuration but only uses the spatial channel difference from two neighboring cells to the user terminal UE to distinguish the signals of the serving cell and the interfering cell. Theoretically, a 5GNR (5G New Radio) with dual receive antennas should be able to resolve two spatial channels. Although this technique does not require any additional standardization work for the transmitting end, it does not rely on any additional signal distinguishing means such as frequency division, code division, interleaver division, but only on space division means, and it is difficult to achieve satisfactory interference cancellation effect. Moreover, this technique is a receiver implementation technique and does not require standardization.

B. Interference cancellation technique based on interference reconstruction subtraction

This technique is to demodulate and decode the interfering signal, reconstruct the interfering signal, and subtract the reconstructed interfering signal from the received signal. If the interfering signal component can be accurately subtracted, the remaining is the desired signal and noise. This is certainly a more efficient interference cancellation technique, and of course, due to the need to fully demodulate and even decode the interfering signal, it also puts higher requirements or more restrictions on the system design, such as resource block allocation, channel estimation, synchronization, signaling, etc.

Disclosure of Invention

In order to solve the technical problem, the embodiment of the invention adopts the following technical scheme:

a method for interference coordination based on UE position comprises the following steps:

determining a serving cell and a neighboring cell of the serving cell;

receiving Reference Signal Received Power (RSRP) respectively measured by UE belonging to the serving cell and between the UE and the serving cell and the neighbor cell, wherein the RSRP is sent by the UE;

determining that the UE is a central UE or an edge UE according to the RSRP between the UE and the serving cell;

positioning the edge UE;

attributing the edge UE to a UE set corresponding to at least one neighbor cell according to the positioning result of the edge UE, wherein the UE in the UE set is the UE which is expected to generate interference on the attributive neighbor cell;

and when the high interference indication is sent to the first adjacent cell, only sending the high interference indication to the UE in the UE set corresponding to the first adjacent cell.

Optionally, the method further comprises:

when receiving an interference overload indication sent by a first neighboring cell, if a first UE scheduled on a PRB indicated by the interference overload indication exists in a UE set of the first neighboring cell, reducing the transmission power of the first UE.

Optionally, the step of positioning the edge UE specifically includes:

establishing a position fingerprint database containing m first RSRP information between the accurate geographical position of the UE to be tested and m cell base stations respectively; the cell comprises a service cell and a neighboring cell of the service cell;

acquiring m pieces of second RSRP information between the current geographic position of the edge UE and m cell base stations respectively;

determining Euclidean distances between the current geographic position of the edge UE and the accurate geographic positions of all the tested UEs according to the first RSRP information and the second RSRP information corresponding to each adjacent cell;

and taking the accurate geographical position of the test UE corresponding to the minimum value in all the Euclidean distances as the geographical position of the edge UE.

Optionally, the step of attributing the edge UE to the UE set corresponding to the at least one neighboring cell according to the positioning result of the edge UE specifically includes:

and calculating the linear distance between the edge UE and the base stations of all the adjacent cells of the service cell, and adding the edge UE into the UE sets corresponding to the three adjacent cells with the closest linear distance.

Optionally, the method may be characterized in that,

and when the edge UE leaves the serving cell, deleting the edge UE from the UE set of all the adjacent cells of the serving cell.

Another aspect of the embodiments of the present invention is to provide an interference coordination apparatus based on a UE location, including:

a first determining module, configured to determine a serving cell and a neighboring cell of the serving cell;

a receiving module, configured to receive reference signal received powers RSRP between the UE and the serving cell and the neighboring cell, where the RSRP is measured by the UE and sent by the UE belonging to the serving cell;

a second determining module, configured to determine, according to RSRP between the UE and the serving cell, that the UE is a center UE or an edge UE;

a positioning module, configured to position the edge UE;

the processing module is used for attributing the edge UE to a UE set corresponding to at least one adjacent cell according to the positioning result of the edge UE, wherein the UE in the UE set is the UE which is expected to generate interference on the attributive adjacent cell;

and the sending module is used for sending the high interference indication only to the UE in the UE set corresponding to the first neighboring cell when sending the high interference indication to the first neighboring cell.

Optionally, the apparatus further comprises:

the power adjustment module is configured to, when receiving an interference overload indication sent by a first neighboring cell, reduce the transmit power of a first UE if the first UE scheduled on a PRB of the interference overload indication exists in a UE set of the first neighboring cell.

Optionally, the positioning module is specifically configured to:

Optionally, the processing module is specifically configured to:

Alternatively to this, the first and second parts may,

the processing module is further configured to delete the edge UE from the UE set of all neighboring cells of the serving cell when the edge UE leaves the serving cell.

The embodiment of the invention has the advantages that the service cell and the adjacent cell of the service cell are determined; receiving Reference Signal Received Power (RSRP) respectively measured by UE belonging to the serving cell and between the UE and the serving cell and the neighbor cell, wherein the RSRP is sent by the UE; determining the UE as a center UE or an edge UE according to the RSRP between the UE and the serving cell; positioning the edge UE; attributing the edge UE to a UE set corresponding to at least one neighbor cell according to the positioning result of the edge UE, wherein the UE in the UE set is the UE which is expected to generate interference on the attributive neighbor cell; and when the high interference indication is sent to the first adjacent cell, only sending the high interference indication to the UE in the UE set corresponding to the first adjacent cell. The interaction frequency of interface signaling between the base station and the base station can be reduced, unnecessary power control of interference overload indication can be reduced, and the throughput of a cell can be improved when the load is higher.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a flow chart of a method provided by an embodiment of the present invention;

FIG. 2 is a block diagram of an apparatus according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a system according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

An embodiment of the present invention provides an interference coordination method based on a UE location, as shown in fig. 1, including:

s101, determining a serving cell and a neighboring cell of the serving cell;

s103, receiving reference signal received powers RSRP which are respectively measured by the UE and are sent by the UE belonging to the serving cell and between the UE and the serving cell and the neighbor cell;

s105, determining that the UE is a central UE or an edge UE according to the RSRP between the UE and the serving cell;

s107, positioning the edge UE;

s109, attributing the edge UE to a UE set corresponding to at least one neighboring cell according to the positioning result of the edge UE, wherein the UE in the UE set is the UE which is expected to generate interference on the attributive neighboring cell;

s111, when sending the high interference indication to the first neighboring cell, only sending the high interference indication to the UE in the UE set corresponding to the first neighboring cell.

Optionally, the method further comprises:

Optionally, the step of positioning the edge UE specifically includes:

Optionally, the method may be characterized in that,

Another aspect of the embodiments of the present invention is to provide an interference coordination apparatus based on a UE location, as shown in fig. 2, including:

a first determining module 201, configured to determine a serving cell and a neighboring cell of the serving cell;

a receiving module 203, configured to receive reference signal received powers RSRP between a UE belonging to the serving cell and the neighboring cell, where the RSRP is measured by the UE;

a second determining module 205, configured to determine that the UE is a center UE or an edge UE according to RSRP between the UE and the serving cell;

a positioning module 207, configured to position the edge UE;

a processing module 209, configured to attribute the edge UE to a UE set corresponding to at least one neighboring cell according to a positioning result of the edge UE, where the UE in the UE set is a UE that is expected to generate interference on the neighboring cell to which the edge UE belongs;

a sending module 211, configured to send the high interference indication only to the UE in the UE set corresponding to the first neighboring cell when sending the high interference indication to the first neighboring cell.

Optionally, the apparatus further comprises:

Optionally, the positioning module 207 is specifically configured to:

Optionally, the processing module 209 is specifically configured to:

Alternatively to this, the first and second parts may,

the processing module 209 is further configured to delete the edge UE from the UE set of all neighboring cells of the serving cell when the edge UE leaves the serving cell.

The embodiments of the present invention are further described below with reference to specific application scenarios.

In the application scenario, the base stations exchange interference coordination related INFORMATION through a LOAD INFORMATION message. The content format of the message is shown in table 1:

field(s)	Description of the invention
		Cell Information
>Cell Information Item
		>>Cell ID
>>UL Interference Overload Indication	OI, overload indication
		>>UL High Interference Information
>>>Target Cell ID
		>>>UL High Interference Indication	HII, high interference indication
>>Relative Narrowband Tx Power(RNTP)

TABLE 1

In uplink transmission, the load indication information exchanged between Xn interfaces of the gnodebs (base stations) is a High Interference Indication (HII) and an interference Overload Indication (OI). When a gNodeB allocates a PRB (PHYSICAL resource Block) to a cell edge user, since it is predicted that this user may interfere with a neighboring cell (because it will use a larger power for transmission) and is also easily interfered by a UE of the neighboring cell (because it is closer to the cell boundary), this sensitive PRB is reported to the neighboring cell (neighboring cell) through a HII message of an Xn interface, which mainly aims to tell that the PRB indicated by the neighboring cell may have a larger interference, and the cell receiving the HII indication does not allocate these PRBs to the edge user and a central user having a higher SINR requirement during scheduling as much as possible.

OI is a measure of noise and interference by the gbodeb, the average uplink interference and thermal noise received on each PRB. When gNodeB monitors that a certain PRB has been interfered by uplink, OI is sent to the adjacent cell to indicate that the PRB has been interfered. The adjacent cells can suppress interference through uplink power control.

In the prior art, in the process of transferring HII and OI, a cell often transfers the HII and OI to all neighboring cells without distinguishing the neighboring cells, which easily causes the waste of signaling resources and cannot control interference with fine granularity. The embodiment of the invention provides an interference coordination method based on UE and cell positions, under the condition that the cell position is known, the UE is positioned according to some measurement information, and the cell possibly interfered by the UE is identified according to the position and scheduling information of the UE. And when the high interference indication is sent to the adjacent cell, only the UE set which possibly generates interference to the adjacent cell is included. And when receiving the interference overload indication of the adjacent cell, selecting the UE from the UE set which possibly generates interference to the adjacent cell for power control. The interference coordination method based on the UE position can improve the efficiency of interference coordination and reduce the interaction of signaling.

The embodiment comprises the following steps:

step one, a user configures an adjacent cell of a service cell base station through a network management system, wherein the adjacent cell comprises position information of the adjacent cell;

step two, UE registers in a service cell and establishes a service;

step three, the service cell configures UE to measure the adjacent cell, and periodically reports RSRP;

step four, the serving cell judges whether the UE is located at the center of the serving cell or at the edge of the serving cell according to the RSRP measured by the UE and between the UE and the serving cell and the neighboring cell respectively, and positions the edge UE;

dividing the edge UE into UE sets of different adjacent cells of the serving cell according to the positioning of the edge UE, wherein the UE in the UE set of the adjacent cells possibly generates interference to the adjacent cells;

step six, when the service cell sends a high interference indication to the adjacent cell, only considering the UE in the UE set of the adjacent cell;

and step seven, when the serving cell receives the interference overload indication of the neighbor cell, only searching the UE scheduled on the PRB from the UE set of the neighbor cell, and reducing the transmitting power of the UE.

The method for positioning the edge UE comprises the following steps:

the location-based positioning method may comprise the following two phases: the method comprises an off-line stage of establishing a position fingerprint map and an on-line fingerprint matching and positioning stage. The offline stage creates a location fingerprint database containing the precise geographic location of the reference point and the RSRP fingerprint. In the online phase, generally, the euclidean distance of a signal space between a reference point RSRP in the location fingerprint map and the online RSRP is calculated, and a point with the minimum euclidean distance is selected as the location of the UE.

The method comprises the following steps:

step one, when configuring a base station cell, besides configuring a neighbor cell list of the cell, configuring position information of a base station to which a neighbor cell belongs, namely a Global Positioning System (GPS) position of the base station.

And step two, after the cell is started, establishing a position fingerprint map based on RSRP by using the test UE. The position fingerprint map is established based on the actually acquired data, and the characteristics of the actual signal propagation environment, such as obstacle occlusion, non-line-of-sight propagation and the like, are completely reserved. The data storage format of the location fingerprint map is [ test UE (longitude, latitude), (cell identity 1, RSRP1), (cell identity 2, RSRP2), (cell identity 3, RSRP3), (cell identity 4, RSRP4) ]. After the cell is started, the test UE is used for moving slowly in a coverage area, the service cell is configured with the test UE to respectively measure RSRP values between the test UE and the service cell and between the test UE and the adjacent cell, the test UE records the position of the test UE and the RSRP values between the test UE and the service cell and between the test UE and the adjacent cell, which are measured by the current position UE, and the RSRP values are recorded in a position fingerprint map database according to a format of (cell identification, RSRP). In the embodiment of the present invention, the location fingerprint map database may only need to record the cell identifiers and RSRPs of at most 4 cells, and if the test UE can measure RSRPs of multiple cells, 4 cells with the largest RSRP values are selected.

And step three, after the position fingerprint map is constructed, the actual UE can be positioned. After the UE is accessed to the service cell, the service cell configures the UE to carry out RSRP measurement and measurement report reporting of the service cell and the adjacent cell. The UE reports the measured RSRP between the UE and the serving cell and the neighboring cell periodically, and the RSRP is recorded as [ (cell identifier 1, RSRP1_ m), (cell identifier 2, RSRP2_ m), (cell identifier 3, RSRP3_ m), (cell identifier 4, RSRP4_ m) ].

And step four, judging whether the UE is the center UE or the edge UE according to the RSRP value of the service cell. When the RSRP of the serving cell is greater than a threshold TRSRP, the UE is considered as a central UE; and when the RSRP value of the serving cell is less than or equal to the threshold TRSRP, the UE is considered as an edge UE. And only the edge UE is positioned and set divided, and the central UE does not process the positioning and set division.

And calculating the matching condition of the edge UE measurement value and the position fingerprint map, wherein the calculation formula of the Euclidean distance is as follows:

in the above formula, d represents the Euclidean distance between the measurement point (the current geographical position of the UE) and the standard point of the position fingerprint map (the accurate geographical position of the UE to be tested), and RSRP_iThe RSRP value of the position fingerprint map standard point is defined, and the RSRP _ mi is the actual RSRP value measured by the UE_iAnd RSRP _ m_iAre the same. And respectively calculating Euclidean distances between the measured value RSRP _ m reported by the edge UE and points in the position fingerprint map, and selecting the position corresponding to the point with the minimum Euclidean distance as the position of the edge UE.

Wherein, the high interference indication updating step is as follows:

as shown in fig. 3, taking cell 1 (serving cell) as an example, each cell generally has more than 6 neighboring cells, i.e., cells 2 to 7 are the neighboring cells of cell 1. Cell 1 maintains a set of UEs for each neighbor cell that UEs in the set may interfere with. In the initial stage, the UE set of each neighboring cell is empty, and as the UE continuously accesses to cell 1, cell 1 can calculate the location of the UE, such as the locations shown by UE1 (five-pointed star) and UE2 (five-pointed star), through the measurement of RSRP of neighboring cells 2 to 7 by the UE. And if the UE is the center UE, not processing the UE. If the UE is an edge UE, positioning and set partitioning of the edge UE is started. On the premise of knowing the position of the edge UE and the position of the cell, calculating the linear distance between the edge UE and all the adjacent cells of the cell 1, and adding the edge UE into a set of three adjacent cells closest to the linear distance between the edge UE and the adjacent cells. When the edge UE leaves the cell 1, the edge UE is deleted from the UE set of all the neighboring cells of the cell 1.

The update principle of the high interference indication is as follows: if the cell decides to schedule the UE in the PRB, the high interference indication of the PRB is set to 1, and the current cell updates the high interference indications of all the UEs to all the neighboring cells in the high interference indication updating process in the prior art. This updating method is inefficient, and taking fig. 3 as an example, the interference caused by the UE1 to the neighboring

cells

3 and 4 is very small, so it is not necessary to update the high interference indication to the neighboring

cells

3 and 4 at all. The implementation method of the invention is that only the high interference indication of the UE set of the neighboring cell is updated to the neighboring cell, because only if the UE is located in the UE set of the neighboring cell, the UE can possibly generate interference to the neighboring cell. The updating method of the high interference indication can effectively reduce the interactive frequency of the signaling and improve the efficiency of the interference coordination algorithm.

The interference overload indication processing steps are as follows:

the purpose of the interference overload indication is to inform the adjacent cell that the PRB of the cell is seriously interfered, and the adjacent cell should properly reduce the sending power of the UE on the PRB according to the interference overload indication. In the traditional interference overload indication transmission process, if the cell is subjected to the overload indication of the neighboring cell, the cell searches for the UE scheduled on the overload PRB in all the UEs and reduces the sending power of the UE. This decision method has a drawback, for example, in fig. 3, if cell 1 is indicated by interference overload of cell 3 and UE1 happens to be located on the PRB indicated by the interference overload, cell 1 should instruct UE1 to decrease the transmission power according to the scheduling method of the prior art. However, in practice, since the UE1 is far from the cell 3, the UE1 hardly causes interference to the cell 3, and the interference of the cell 3 may be caused by UEs in other neighboring cells of the cell 3.

The processing method of the embodiment of the invention is also processed according to the UE set of the adjacent area. When the cell 1 receives the interference overload indication of the neighboring cell 3, the cell 1 searches the UE set of the neighboring cell 3, and if the UE set has the UE scheduled on the PRB indicated by the interference overload, the transmission power of the UE is reduced. Cell 1 does not operate on UEs outside the set of UEs in the neighboring cell 3. The scheduling method can avoid unnecessary scheduling and increase the throughput of the UE.

The embodiment of the invention has the advantages of reducing the interaction frequency of interface signaling between the base station and the base station, reducing unnecessary power control of interference overload indication and improving the throughput of the cell when the load is higher.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A method for interference coordination based on UE position, comprising:

determining a serving cell and a neighboring cell of the serving cell;

positioning the edge UE;

attributing the edge UE to a UE set corresponding to at least one neighbor cell according to the positioning result of the edge UE, wherein the UE in the UE set is the UE which is expected to generate interference on the attributive neighbor cell; and when the high interference indication is sent to the first adjacent cell, only sending the high interference indication to the UE in the UE set corresponding to the first adjacent cell.

2. The method of claim 1, further comprising:

3. The method of claim 1, wherein the step of locating the edge UE specifically comprises:

4. The method according to claim 1, wherein the step of attributing the edge UE to a UE set corresponding to at least one neighboring cell according to the positioning result of the edge UE specifically includes:

5. The method of any of claims 1-4,

6. An apparatus for interference coordination based on UE location, comprising:

a positioning module, configured to position the edge UE;

7. The apparatus of claim 6, further comprising:

8. The apparatus of claim 6, wherein the positioning module is specifically configured to:

9. The apparatus of claim 6, wherein the processing module is specifically configured to:

10. The apparatus of any of claims 6-9, wherein the processing module,

and deleting the edge UE from the UE set of all the adjacent cells of the serving cell when the edge UE leaves the serving cell.