CN103945480A - Method, device and system for eliminating interference between pico cell and high speed user device in heterogeneous network - Google Patents

Abstract

The object of the present invention is to provide a method, device and system for eliminating interference between pico cells and high-speed user equipment for heterogeneous networks. Wherein, the heterogeneous network includes a macro cell and a pico cell, both of which have the same geographic coverage area, and when the high-speed user equipment corresponding to the macro cell enters the coverage of the pico cell, the pico cell is the high-speed user equipment Configuring reserved resources to eliminate interference between the pico cell and the high-speed user equipment; the macro cell communicates with the high-speed user equipment on the reserved resources. The pico cell coordinates with the macro cell on reserved resources to eliminate interference to/from high-speed user equipment in the macro cell, avoids frequent handover in the heterogeneous network, reduces the amount of air signaling, and thus improves the performance of the heterogeneous network. Efficiency, and as much as possible to ensure the continuity of high-speed user equipment services, so that the high-speed user equipment can obtain a better experience.

Description

Method, device and system for eliminating interference between pico cells and high-speed user equipment in heterogeneous networks

technical field

The invention relates to the technical field of mobile communication, in particular to a technology for eliminating interference between a pico cell and high-speed user equipment used in a heterogeneous network. the

Background technique

Recently, a heterogeneous network (HetNet, heterogeneous network) has been widely discussed in 3GPP LTE-A (Long Term Evolution Advanced) for improving system performance. Small cells have been widely accepted in LTE as a promising technology that can significantly increase cell capacity. Moreover, the commercial application of small cells is also attractive to operators all over the world. the

However, due to the addition of small cells in the system, the different coverage of the cells causes serious problems in the mobility management of heterogeneous networks. The introduction of small cells, such as pico cells, will generate additional interference and more frequent handovers due to the smaller coverage of pico cells. the

Currently, when an activated user equipment moves from a macro cell to a pico cell, if it satisfies the handover conditions, it will trigger a normal handover process, which is defined by 3GPPTS 36.300. And, through a series of RRC signaling, X2 signaling and S1 signaling, the path of the user plane is handed over from the macro cell to the pico cell by the serving gateway (SGW, Serving Gateway). the

Likewise, when the activated user equipment moves from the pico cell to the macro cell, another handover procedure will be performed. And, also through the above air signaling, the path of the user plane is switched back from the pico cell to the macro cell by the SGW. the

In summary, due to the relatively small coverage of pico cells, existing solutions will generate more frequent handovers, resulting in more over-the-air signaling and poorer user experience. Therefore, for heterogeneous network scenarios, more effective solutions are needed. the

Contents of the invention

In order to avoid unnecessary over-the-air handover and ping-pong effect, a consensus has been reached: when the user equipment is close to a small cell, the high-speed user equipment should not be handed over to the small cell. However, if the high-speed user equipment is not handed over to the small cell, the high-speed user equipment may receive strong interference when passing through the small cell. The object of the present invention is to provide a method, device and system for eliminating interference between pico cells and high-speed user equipment for heterogeneous networks. the

According to one aspect of the present invention, a method for eliminating interference between a pico cell and high-speed user equipment for a heterogeneous network is provided, wherein the heterogeneous network includes a macro cell and a pico cell, and both have the same geographic coverage In an area, the high-speed user equipment includes user equipment whose speed exceeds a predetermined threshold, wherein the method includes:

a When the high-speed user equipment corresponding to the macro cell enters the coverage of the pico cell, the pico cell configures reserved resources for the high-speed user equipment to eliminate interference between the pico cell and the high-speed user equipment;

b. The macro cell communicates with the high-speed user equipment on the reserved resource. the

According to another aspect of the present invention, there is also provided an apparatus for eliminating interference between a pico cell and high-speed user equipment in a heterogeneous network, wherein the heterogeneous network includes the pico cell and has the same geographical coverage as the pico cell In a macro cell of an area, the high-speed user equipment includes user equipment whose speed exceeds a predetermined threshold, wherein the apparatus includes:

A resource configuration device, configured to configure reserved resources for the high-speed user equipment when the high-speed user equipment corresponding to the macro cell enters the coverage of the pico cell, so as to eliminate interference between the pico cell and the high-speed user equipment ;

Resource indication means, configured to send indication information about the reserved resource to the macro cell, so that the macro cell communicates with the high-speed user equipment on the reserved resource. the

According to still another aspect of the present invention, there is also provided an apparatus for assisting a macro cell in a heterogeneous network to eliminate interference between a pico cell and high-speed user equipment, wherein the heterogeneous network includes the macro cell and its For pico cells in the same geographic coverage area, the high-speed user equipment includes user equipment whose speed exceeds a predetermined threshold, wherein the device includes:

An instruction transceiving means, configured to receive indication information of reserved resources configured for the high-speed user equipment from the pico cell when the high-speed user equipment corresponding to the macro cell enters the coverage of the pico cell;

Communication means, configured to communicate with the high-speed user equipment on the reserved resource. the

According to still another aspect of the present invention, a system for eliminating interference between a pico cell and high-speed user equipment for a heterogeneous network is provided, wherein the heterogeneous network includes a macro cell and a pico cell, and both of them have geographical In the same coverage area, the high-speed user equipment includes user equipment whose speed exceeds a predetermined threshold, wherein the system includes the aforementioned method for eliminating the gap between the pico cell in a heterogeneous network and the high-speed user equipment according to another aspect of the present invention A device for interference, and a device for assisting a pico cell in a macro cell in a heterogeneous network to eliminate interference with high-speed user equipment as described above according to yet another aspect of the present invention. the

Compared with the prior art, the present invention provides an effective solution for the mobility of high-speed user equipment in a heterogeneous network, wherein the pico cell coordinates with the macro cell on reserved resources to eliminate the Interference with user equipment. The present invention avoids frequent switching in the heterogeneous network, reduces the number of air signaling, thereby improves the efficiency of the heterogeneous network, and ensures the continuity of the service of the high-speed user equipment as much as possible, so that the high-speed user equipment obtains better experience. the

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of the non-limiting embodiments made with reference to the following drawings:

Fig. 1 shows an exemplary application scenario according to the present invention;

Figure 2 shows a flow chart of a method for eliminating interference between a pico cell and a high-speed user equipment in cooperation with a macro cell and a pico cell in a heterogeneous network according to a preferred embodiment of the present invention;

FIG. 3 shows a flowchart of a method for eliminating interference between a pico cell and a high-speed user equipment in cooperation with a macro cell and a pico cell in a heterogeneous network according to another preferred embodiment of the present invention;

Fig. 4 shows a schematic diagram of a base station of a macro cell and a pico cell cooperating to eliminate interference between a pico cell and high-speed user equipment in a heterogeneous network according to a preferred embodiment of the present invention. the

The same or similar reference numerals in the drawings represent the same or similar components. the

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings. the

Based on the existing handover process, an improved solution is proposed in the present invention to realize effective mobility management in heterogeneous network scenarios. For the situation where one or more user equipments belonging to the macro cell pass through the pico cell, in addition to the solution of handing over these user equipments from the macro cell to the pico cell, the present invention provides another solution: these user equipments are still managed by the macro cell The cell provides services on some specific resources, while the pico cell will reserve these resources to eliminate the interference it generates to/from these user equipments on the downlink/uplink. the

As shown in FIG. 1 , the heterogeneous network includes a macro cell 10 and a pico cell 20 , both of which have the same geographic coverage area. Here, geographically identical coverage means that the macro cell 10 and the pico cell 20 have the same coverage area geographically. The user equipments 3 and 4 correspond to the macro cell 10 , that is, the user equipments 3 and 4 are within the coverage of the macro cell 10 , and their moving paths will pass through the pico cell 20 . the

Here, it may be determined whether user equipments 3 and 4 belong to high-speed user equipments by setting a predetermined threshold. Moreover, the predetermined threshold can be adjusted according to specific application scenarios. The macro cell 10 can obtain the mobility status information of the user equipment in various ways, for example, the mobility status information of the user equipment can be reported by the user equipment to the macro cell 10, or obtained by the macro cell 10 in other ways, such as according to the sound reference signal is estimated. For example, the macro cell 10 configures the measurement report of the user equipment, adding an additional movement threshold to assist the user equipment to judge its mobile status, such as a high-speed moving device or a low-speed moving device; subsequently, when the user equipment reports the measurement report to the macro cell 10 , including information about its movement state. In the following, for the convenience of describing the present invention, the user equipment 3 is mostly taken as an example of high-speed user equipment, and it is labeled as high-speed user equipment 3 . the

When the high-speed user equipment 3 enters the coverage of the pico cell 20, the pico cell 20 configures reserved resources for the high-speed user equipment 3, so as to eliminate the interference between the pico cell 20 and the high-speed user equipment 3. Here, the resource utilization pattern (resource utilization pattern) of reserved resources may have multiple granularities, such as subframe (subframe) utilization pattern. In the case of considering the quality of service (QoS, Quality of Service) and other factors, it is also possible to use a smaller granularity, such as resource block (RB, Resource Block) utilization mode. The resource utilization pattern can be composed of two parts, including the resource utilization pattern of the downlink and the resource utilization pattern of the uplink. Herein, for the convenience of describing the present invention, the subframe utilization mode is mostly used as an example. the

The macro cell 10 communicates with the high-speed user equipment 3 on the reserved resource. For example, the macro cell 10 reconfigures the high-speed user equipment 3 through RRC signaling, and schedules the high-speed user equipment 3 on the reserved resource. the

For the reserved subframe, on the downlink, the pico cell 20 will not transmit any radio signal, and the macro cell 10 can schedule on the reserved subframe to transmit data to the high-speed user equipment 3, so as to eliminate the impact of the pico cell 20 on the high-speed user equipment. The interference caused by the device 3; on the uplink, the pico cell 20 can also reserve specific resources, and the high-speed user equipment 3 can send uplink data to the macro cell 10 on the reserved resources, so as to eliminate the interference of the high-speed user equipment 3 to the pico cell 20 interference. Thus, the uplink/downlink interference between the pico cell 20 and the high-speed user equipment 3 can be eliminated. For other subframes, the pico cell 20 can still be scheduled normally. the

Subsequently, when the high-speed user equipment 3 leaves the coverage of the pico cell 20 , the macro cell 10 will notify the pico cell 20 to stop configuring reserved resources for the high-speed user equipment 3 . the

Fig. 2 is a flow chart of a method according to a preferred embodiment of the present invention, showing a process in which a macro cell cooperates with a pico cell to eliminate interference between a pico cell and high-speed user equipment in a heterogeneous network. the

With reference to FIG. 1 , the pico cell 20 is within the coverage of the macro cell 10 , that is, both have the same geographic coverage area. The high-speed user equipment 3 is within the coverage of the macro cell 10 , and its moving path will pass through the pico cell 20 . the

In step S201a, the macro cell 10 configures measurement parameters for the user equipment within its coverage area, and these measurement parameters may help to control the function of connection mobility of the user equipment. In step S201b, when a predetermined rule is satisfied, these user equipments are triggered to report corresponding measurement reports to the macro cell 10 according to the measurement parameters configured by the macro cell 10 . the

In step S202, the macro cell 10 makes a handover decision to the corresponding user equipment according to the measurement report reported by the user equipment and RRM (Radio Resource Management, radio resource management) information. the

The above process is the same as the existing corresponding process defined by LTE-Advanced, so it will not be described in detail here. the

In step S203, when a specific user equipment is selected for handover and certain conditions are met, for example, the selected user equipment is a high-speed user equipment, the macro cell 10 sends a handover request about the selected high-speed user equipment to the pico cell 20 (HANDOVER REQUEST), to transfer necessary information to the pico cell 20 for its handover preparation. These information include X2 signaling context of user equipment, S1EPC (Evolved Packet Core, evolved packet core network) signaling context of user equipment, RRC (Radio Resource Control, radio resource control) context and QoS information. Of course, the indication information of the high-speed user equipment passing through the pico cell 20 should also be included. the

Here, the macro cell 10 may select one or more user equipments to perform handover as long as they meet the handover conditions. Preferably, the aforementioned handover condition may further include that the residence time of the selected user equipments in the picocell 20 is similar. Further, the macro cell 10 may first establish a group for the selected multiple high-speed user equipments, and send a handover request related to the high-speed user equipment group to the pico cell 20 . the

For ease of description, the macro cell 10 selects a high-speed user equipment 3 to request a handover to the pico cell 20 as an example for illustration. However, those skilled in the art should understand that these examples are only used to illustrate the purpose of the present invention, and should not be regarded as any limitation to the present invention, that is, for the situation of selecting multiple high-speed user equipments for handover, the present invention The same applies to inventions. the

In step S204, after receiving its handover request for the high-speed user equipment 3 from the macro cell 10, the pico cell 20 configures reserved resources for the high-speed user equipment 3 in response to the handover request. Based on the received QoS information of E-RAB (Enhanced-Radio Access Bear, enhanced radio access bearer) and the radio resources of the pico cell 20, the pico cell 20 performs strategy selection and access control. Here, the pico cell 20 decides to reject the handover request, but selects an interference cancellation mechanism co-scheduled with the macro cell 10, for example, the pico cell 20 configures reserved resources for the high-speed user equipment 3 requesting handover, such as reserving a specific subframe, For the macro cell to provide services for the high-speed user equipment 3 on reserved resources. Wherein, in the reserved subframe, the pico cell 20 still needs to transmit at least a CRS signal (Cell-specific Reference Signal, cell reference signal). the

In step S205, the pico cell 20 sends a handover refusal message corresponding to its handover request to the macro cell 10, and the handover refusal message includes indication information of reserved resources configured for the high-speed user equipment 3 requesting handover. For example, the pico cell 20 sends a HANDOVERREQUEST Negative ACKNOWLEDGE (NACK) message to the macro cell, which carries the resource utilization mode of reserved resources configured by the pico cell 20 for the high-speed user equipment 3 requesting handover. Preferably, the handover decision message may also carry other information, for example, in the case of a high-speed user equipment group requesting handover, the pico cell 20 may decide to handover only part of the high-speed user equipment, that is, the high-speed user equipment group Other high-speed user equipments in the configuration reserved resources, so that the handover decision message may also include the updated high-speed user equipment group (including the high-speed user equipments for which the picocell 20 configures reserved resources) and its identification information, as well as the associated Subframe utilization mode. the

After receiving the handover rejection message sent by the pico cell 20 corresponding to the previous handover request, the macro cell 10 provides services to the high-speed user equipment 3 on the reserved resources configured by the pico cell 20 according to the indication information of the reserved resources included therein , to avoid interference to/from the pico cell 20 . In step S206a, after receiving the NACK message, the macro cell 10 configures RRM/RLM (Radio Link Mornitor, radio link monitoring)/CSI (Channel State Information, channel state information) for restricted measurement reports. In step S206b, the high-speed user equipment 3 will be triggered according to a predetermined rule to report a corresponding measurement report to the macro cell 10 according to the configured RRM/RLM/CSI restrictive parameters. the

In step S207, the macro cell 10 determines whether the high-speed user equipment 3 has moved out of the pico cell 20 based on the received RLM restricted measurement report. An exemplary judgment condition is shown below:

If the reference signal received power (RSRP, Reference Signal Receiving Power) of the pico cell < the reference signal received power of the macro cell - T, that is, RSRP (pico cell) < RSRP (macro cell) - T, then the high-speed user equipment 3 is in the pico cell Out of coverage, where T is a predetermined threshold. the

When it is determined that the high-speed user equipment 3 moves out of the coverage of the pico cell 20, the macro cell 10 sends a notification message to the pico cell 20 about stopping the configuration of reserved resources for the high-speed user equipment 3, such as the macro cell 10 sends to the pico cell 20 "Stop Coordination Request (StopCoordination Request)" message, which carries the identification information of the high-speed user equipment 3. the

For the situation where there are multiple high-speed user equipments requesting handover, when all high-speed user equipments are outside the coverage of the pico cell 20, the macro cell 10 sends a notification message to the pico cell 20 about stopping the configuration of reserved resources for these high-speed user equipments . the

In step S208 , according to the notification message sent by the macro cell 10 , the pico cell 20 stops configuration of corresponding reserved resources for coordinated scheduling with the macro cell 10 . That is, the pico cell 20 stops configuring the reserved subframes of the high-speed user equipment 3 and returns to normal operation. the

In step S209, the pico cell 20 sends a "Stop Coordination Request Acknowledge" message to the macro cell 10. the

In step S210, the macro cell 10 reconfigures the channel condition measurement report for the high-speed user equipment 3, and resumes normal operation. the

Fig. 3 is a flow chart of a method according to another preferred embodiment of the present invention, showing a process in which a macro cell cooperates with a pico cell to eliminate interference between a pico cell and high-speed user equipment in a heterogeneous network. the

Still referring to FIG. 1 , the pico cell 20 is within the coverage of the macro cell 10 , that is, both have the same geographical coverage area. The high-speed user equipment 3 is within the coverage of the macro cell 10 , and its moving path will pass through the pico cell 20 . the

The preferred embodiment shown in FIG. 3 avoids interference between the pico cell 20 and the high-speed user equipment 3 by using ABS (almost blank subframe, almost blank subframe) in the pico cell 20. Therefore, this pico cell 20-oriented ABS configuration process can be used to solve the strong interference problem generated when the high-speed user equipment 3 in the macro cell 10 passes through the coverage of the pico cell 20 . the

Specifically, in step S301a, the macro cell 10 configures measurement reports for all UEs within its coverage area, and adds a mobility threshold to assist the UEs to determine their mobility status, that is, high-speed UEs or low-speed UEs. The threshold is determined by the macro cell 10 and can be adjusted according to the actual situation. the

In step S301b, when the high-speed user equipment 3 is close to the pico cell 20, because the RSRP received from the pico cell is stronger than the RSRP received from the macro cell 10, the A3 event is triggered, and the high-speed user equipment 3 reports to the macro cell 10 Submit the measurement report. In addition to the usual measurement parameters, the high-speed user equipment 3 also sends high-speed user equipment indication information to the macro cell 10, for example, a high-speed user equipment indicator is added to the measurement report, which can occupy one bit, and "1" is used to indicate the high-speed user equipment , using “0” to represent low-speed user equipment to inform the macro cell 10 that it should be avoided from being handed over to the pico cell 20 . The estimation of the mobility state of the user equipment can be obtained by calculating the number of handovers of the user equipment within a predetermined time. An exemplary A3 event is shown below:

Mn+Ofn+Ocn-Hys＞Mp+Ofp+Ocp+Off

Among them, Mn is the measurement result of the adjacent cell, without considering any offset;

Ofn is the frequency specific offset of the neighboring cell, i.e. the offset frequency parameter (offsetFreq) defined in the measurement configuration (measObjectEUTRA) of EUTRA, which corresponds to the frequency of the neighboring cell;

Ocn is the cell-specific offset of the adjacent cell, that is, the cell-specific offset parameter (cellIndividualOffset) defined in the EUTRA measurement configuration (measObjectEUTRA). If it is not configured for the adjacent cell, Ocn is set to 0;

Mp is the measurement result of the primary serving cell, regardless of any offset;

Ofp is the frequency specific offset of the primary serving cell, i.e. the offset frequency parameter (offsetFreq) defined in the EUTRA measurement configuration (measObjectEUTRA), which corresponds to the carrier frequency of the primary serving cell;

Ocp is the cell-specific offset of the primary serving cell, that is, the cell-specific offset parameter (cellIndividualOffset) defined in the EUTRA measurement configuration (measObjectEUTRA). If it is not configured for a pico cell, set Ocp to 0;

Hys is the hysteresis parameter of this event, that is, the hysteresis parameter defined for this event in EUTRA's report configuration (reportConfigEUTRA);

Off is the offset parameter of the event, that is, the a3 offset defined for the event in the EUTRA report configuration (reportConfigEUTRA). the

In step S302, when receiving the measurement report triggered by the A3 event, the macro cell 10 classifies the mobility state of the user equipment according to the high-speed user equipment indicator therein. At the same time, the macro cell 10 will detect the type of the target cell for potential handover, that is, the target cell is a macro cell or a pico cell, and the target cell will cause strong interference to the user equipment in the macro cell 10. the

According to the mobile state level of the user equipment, the macro cell 10 will perform the following operations respectively:

1) For low-speed user equipment, the macro cell 10 will start a handover operation;

2) For the high-speed user equipment, the macro cell 10 will request the pico cell 20 to configure reserved resources for it, and it will not be handed over to the pico cell 20 any more. the

In step S303, for the high-speed user equipment 3, the macro cell 10 sends a configuration request about configuring reserved resources for the high-speed user equipment 3 to the target pico cell, for example, the macro cell 10 sends an "ABS turn-on request (ABS Turn- on Request)" message. Preferably, when the macro cell 10 is currently providing a VoIP (Voice over Internet Protocol, VoIP) service for the high-speed user equipment 3, the ABS opening request can further include the next transmission time message of the VoIP service. the

In step S304 , the pico cell 20 configures reserved resources, such as ABS, for the high-speed user equipment 3 in response to the configuration request sent by the macro cell 10 . According to the current ABS status of the pico cell 20, the pico cell 20 will perform the following operations respectively:

1) If the pico cell 20 is not currently configured with ABS and the high-speed user equipment 3 is using the VoIP service, the pico cell 20 decides to be a high-speed user according to the next transmission time message and the VoIP data transmission interval of the high-speed user equipment 3 in the ABS activation request Which subframe is used when device 3 configures ABS;

2) If the femto cell 20 is not currently configured with ABS and the high-speed user equipment 3 does not use the VoIP service, the femto cell 20 can configure any subframe as a reserved subframe;

3) If the pico cell 20 is currently configured with ABS and the received ABS opening request is not for high-speed user equipment using VoIP services, the pico cell 20 does not need to additionally configure reserved subframes for the high-speed user equipment;

4) If the femtocell 20 has currently configured ABS and the received ABS opening request is for a high-speed user equipment using VoIP service, the femtocell 20 reconfigures the ABS according to the next transmission time message of the high-speed user equipment 3 in the ABS opening request . the

In step S305, the pico cell 20 sends indication information about reserved resources configured for the high-speed user equipment 3 to the macro cell 10. For example, after the pico cell 20 configures or reconfigures ABS for the high-speed user equipment 3, the pico cell 20 sends indication information of the configured ABS to the macro cell 10 through an existing X2ABS load-related message. the

In step S306, after the macro cell 10 receives the indication information of the configured ABS from the pico cell 20, the macro cell 10 resets the measurement configuration information through RRC signaling and makes a corresponding scheduling decision according to the configured ABS. the

Since ABS is used in the pico cell 20 to protect the high-speed user equipment 3 in the macro cell 10, when the high-speed user equipment 3 leaves the pico cell 20, ABS should be stopped to avoid waste of resources. In step S307, the macro cell 10 detects whether the high-speed user equipment 3 is still in the coverage of the pico cell 20, and when it leaves the pico cell 20, sends a notification message about stopping the configuration of reserved resources to the pico cell 2, for example, to the pico cell 20. Cell 20 sends an "ABS Turn-off Request (ABS Turn-off Request)" message. Here, there are at least two ways to detect whether the high-speed user equipment 3 is outside the coverage of the pico cell 20, so that the pico cell 20 stops configuring ABS for it:

1) When the high-speed user equipment 3 detects that the received RSRP (Reference Signal Receiving Power, reference signal receiving power) or RSRQ (Reference Signal Receiving Quality, reference signal receiving quality) is lower than the corresponding predetermined threshold, the high-speed user equipment 3 will report to the The macro cell 10 sends a specific message to indicate that the interference from the pico cell 20 is currently small, so that the pico cell 20 can be notified to stop the ABS configuration;

2) When the macro cell 10 receives a measurement report triggered by another A3 event, wherein the identity information of the target cell is different from the identity information of the pico cell in the measurement report of the A3 event triggered by the high-speed user equipment 3, the macro cell 10 knows that the high-speed user equipment 3 has left the pico cell 20, and may notify the pico cell 20 to stop ABS configuration. the

In step S308, after receiving the ABS deactivation request sent by the macro cell 10, the pico cell 20 determines whether to stop configuring ABS according to other received ABS deactivation requests. the

Fig. 4 is a schematic diagram of an apparatus according to a preferred embodiment of the present invention, showing base stations of a macro cell and a pico cell cooperating to eliminate interference between a pico cell and high-speed user equipment in a heterogeneous network. the

In this document, a macro cell and its corresponding base station, that is, a "macro cell base station" are used equally without distinction. Similarly, a pico cell and its corresponding base station, that is, a "pico cell base station" are also used equally without distinction. the

With reference to FIG. 1 , the pico cell 20 is within the coverage of the macro cell 10 , that is, both have the same geographic coverage area. The high-speed user equipment 3 is within the coverage of the macro cell 10 , and its moving path will pass through the pico cell 20 . the

As shown in FIG. 4 , the macro cell base station 10 includes an indication transceiving device 101 and a communication device 102 ; the pico cell base station 20 includes a resource configuration device 201 and a resource indication device 202 . the

When the high-speed user equipment 3 enters the coverage of the pico cell 20, the resource allocation device 201 of the pico-cell base station 20 configures reserved resources (reserved resources) for the high-speed user equipment 3, so as to eliminate the gap between the pico cell 20 and the high-speed user equipment 3 Interference between. Here, resource utilization patterns (resource utilization patterns) of reserved resources may have multiple granularities, such as subframe (subframe) utilization patterns. In the case of considering the quality of service (QoS, Quality of Service) and other factors, it is also possible to use a smaller granularity, such as resource block (RB, Resource Block) utilization mode. The resource utilization pattern can be composed of two parts, including the resource utilization pattern of the downlink and the resource utilization pattern of the uplink. Herein, for the convenience of describing the present invention, the subframe utilization mode is mostly used as an example. the

Subsequently, the resource indication unit 202 of the pico cell base station 20 sends indication information of reserved resources configured for the high-speed user equipment 3 to the macro cell 10 . Correspondingly, the indication transceiving means 101 of the macro cell base station 10 receives the indication information about reserved resources from the pico cell 20 . the

The communication device 102 of the macro cell base station 10 communicates with the high-speed user equipment 3 on the reserved resource. For example, the communication device 102 reconfigures the high-speed user equipment 3 through RRC signaling, and schedules the high-speed user equipment 3 on the reserved resource. the

For the reserved subframe, on the downlink, the pico cell 20 will not transmit any radio signal, and the macro cell 10 can schedule on the reserved subframe to transmit data to the high-speed user equipment 3, so as to eliminate the impact of the pico cell 20 on the high-speed user equipment. The interference caused by the device 3; on the uplink, the pico cell 20 can also reserve specific resources, and the high-speed user equipment 3 can send uplink data to the macro cell 10 on the reserved resources, so as to eliminate the interference of the high-speed user equipment 3 to the pico cell 20 interference. Thus, the uplink/downlink interference between the pico cell 20 and the high-speed user equipment 3 can be eliminated. For other subframes, the pico cell 20 can still be scheduled normally. the

When the high-speed user equipment 3 leaves the coverage of the pico cell 20 , the macro cell 10 may also notify the pico cell 20 to stop configuring reserved resources for the high-speed user equipment 3 . the

In a preferred application scenario of the macro cell base station 10 and the pico cell base station 20 shown in FIG. 4 , the pico cell base station 20 decides whether to configure reserved resources for the high speed user equipment 3 . the

Specifically, the macro cell 10 configures measurement parameters for the user equipment within its coverage, and these measurement parameters may help to control the function of connecting and moving the user equipment. When a predetermined rule is satisfied, these user equipments are triggered to report corresponding measurement reports to the macro cell 10 according to the measurement parameters configured by the macro cell 10 . the

The macro cell 10 makes a handover decision for the corresponding user equipment according to the measurement report reported by the user equipment and RRM (Radio Resource Management, radio resource management) information. the

When a specific user equipment is selected for handover and certain conditions are met, for example, the selected user equipment is a high-speed user equipment, the instruction transceiver unit 101 of the macro cell base station 10 sends a handover about the selected high-speed user equipment to the pico cell 20 request (HANDOVER REQUEST) to deliver necessary information to the pico cell 20 for handover preparation. These information include X2 signaling context of user equipment, S1EPC signaling context of user equipment, RRC context and QoS information. Of course, the indication information of the high-speed user equipment passing through the pico cell 20 should also be included. the

Here, the macro cell 10 may select one or more user equipments to perform handover as long as they meet the handover conditions. Preferably, the aforementioned handover condition may further include that the residence time of the selected user equipments in the picocell 20 is similar. Further, the macro cell 10 may first establish a group for the selected multiple high-speed user equipments, and send a handover request related to the high-speed user equipment group to the pico cell 20 . the

For ease of description, the macro cell 10 selects a high-speed user equipment 3 to request a handover to the pico cell 20 as an example for illustration. However, those skilled in the art should understand that these examples are only used to illustrate the purpose of the present invention, and should not be regarded as any limitation to the present invention, that is, for the situation of selecting multiple high-speed user equipments for handover, the present invention The same applies to inventions. the

After the resource allocation device 201 of the pico cell base station 20 receives its handover request about the high-speed user equipment 3 from the macro cell 10, it configures reserved resources for the high-speed user equipment 3 in response to the handover request. Based on the received QoS information of E-RAB (Enhanced-Radio Access Bear, enhanced radio access bearer) and the radio resources of the pico cell 20, the pico cell 20 performs strategy selection and access control. Here, the resource configuration device 201 decides to reject the handover request, but selects an interference cancellation mechanism coordinated with the macro cell 10. For example, the resource configuration device 201 configures reserved resources for the high-speed user equipment 3 requesting the handover, such as reserving a specific frames for the macro cell to provide services for the high-speed user equipment 3 on reserved resources. Wherein, in the reserved subframe, the pico cell 20 still needs to transmit at least a CRS signal (Cell-specific Reference Signal, cell reference signal). The resource configuration device 201 sends a handover refusal message corresponding to its handover request to the macro cell 10, the handover refusal message including indication information of reserved resources configured for the high-speed user equipment 3 requesting handover. For example, the resource configuration device 201 sends a HANDOVER REQUEST NegativeACKNOWLEDGE (NACK) message to the macro cell, which carries the resource utilization mode of reserved resources configured by the pico cell 20 for the high-speed user equipment 3 requesting handover. Preferably, the handover decision message may also carry other information, for example, in the case of a high-speed user equipment group requesting handover, the pico cell 20 may decide to handover only part of the high-speed user equipment, that is, the high-speed user equipment group Other high-speed user equipments in the configuration reserved resources, so that the handover decision message may also include the updated high-speed user equipment group (including the high-speed user equipments for which the picocell 20 configures reserved resources) and its identification information, as well as the associated Subframe utilization mode. the

After the instruction transceiver device 101 of the macro cell base station 10 receives the handover rejection message sent by the pico cell 20 corresponding to the previous handover request, the communication device 102 uses the reserved resources configured in the pico cell 20 according to the indication information contained therein. High-speed user equipment 3 is served on resources to avoid interference to/from the pico cell 20 . After instructing the transceiver device 101 to receive the NACK message, the communication device 102 configures RRM/RLM (Radio Link Momitor, radio link monitoring)/CSI (Channel State Information, channel state information) for restricted measurement reports. The high-speed user equipment 3 will be triggered according to a predetermined rule to report a corresponding measurement report to the macro cell 10 according to the configured RRM/RLM/CSI restrictive parameters. the

Based on the RLM restricted measurement report reported by the high-speed user equipment 3, the notification means 103 of the macro cell base station 10 determines whether the high-speed user equipment 3 has moved out of the pico cell 20. An exemplary judgment condition is shown below:

If the reference signal received power (RSRP, Reference Signal Receiving Power) of the pico cell < the reference signal received power of the macro cell - T, that is, RSRP (pico cell) < RSRP (macro cell) - T, then the high-speed user equipment 3 is in the pico cell Out of coverage, where T is a predetermined threshold. the

When it is determined that the high-speed user equipment 3 has moved out of the coverage of the pico cell 20, the notification means 103 sends a notification message to the pico cell 20 about stopping the allocation of reserved resources for the high-speed user equipment 3, such as the notification means 103 sends to the pico cell 20 a " Stop Coordination Request (StopCoordination Request)" message, which carries the identification information of the high-speed user equipment 3. the

For the situation where there are multiple high-speed user equipments requesting handover, when all the high-speed user equipments are outside the coverage of the pico cell 20, the notification means 103 sends a notification message about stopping to configure reserved resources for these high-speed user equipments to the pico cell 20 . the

The notification receiving unit 203 of the picocell base station 20 receives the notification message sent by the macro cell 10 , and the configuration control unit 204 stops configuration of corresponding reserved resources for coordinated scheduling with the macro cell 10 . That is, the configuration control means 204 stops configuring the reserved subframes of the high-speed user equipment 3, and meanwhile the pico cell 20 resumes normal operation. the

The notification receiver 203 also sends a “Stop Coordination Request Acknowledge” message to the macro cell 10 . the

Subsequently, the macro cell 10 reconfigures the channel condition measurement report for the high-speed user equipment 3 and resumes normal operation. the

In another preferred application scenario of the macro cell base station 10 and the pico cell base station 20 shown in FIG. almost blank subframe, almost blank subframe) to avoid interference between the pico cell 20 and the high-speed user equipment 3. Therefore, this pico cell 20-oriented ABS configuration process can be used to solve the strong interference problem generated when the high-speed user equipment 3 in the macro cell 10 passes through the coverage of the pico cell 20 . the

The macro cell 10 configures measurement reports for all user equipments within its coverage area, and adds a mobile threshold to assist the user equipment to judge its mobile state, that is, high-speed user equipment or low-speed user equipment. The threshold is determined by the macro cell 10 and can be adjusted according to the actual situation. the

When the high-speed user equipment 3 approaches the pico cell 20 , because the RSRP it receives from the pico cell is stronger than the RSRP received from the macro cell 10 , the A3 event is triggered, and the high-speed user equipment 3 reports a measurement report to the macro cell 10 . In addition to the usual measurement parameters, the high-speed user equipment 3 also sends high-speed user equipment indication information to the macro cell 10, for example, a high-speed user equipment indicator is added to the measurement report, which can occupy one bit, and "1" is used to indicate the high-speed user equipment , using “0” to represent low-speed user equipment to inform the macro cell 10 that it should be avoided from being handed over to the pico cell 20 . The estimation of the mobility state of the user equipment can be obtained by calculating the number of handovers of the user equipment within a predetermined time. An exemplary A3 event is shown below:

Mn+Ofn+Ocn-Hys＞Mp+Ofp+Ocp+Off

in,

Among them, Mn is the measurement result of the adjacent cell, without considering any offset;

Ofn is the frequency specific offset of the neighboring cell, i.e. the offset frequency parameter (offsetFreq) defined in the measurement configuration (measObjectEUTRA) of EUTRA, which corresponds to the frequency of the neighboring cell;

Ocn is the cell-specific offset of the adjacent cell, that is, the cell-specific offset parameter (cellIndividualOffset) defined in the measurement configuration (measObjectEUTRA) of EUTRA. If it is not configured for the adjacent cell, Ocn is set to 0;

Mp is the measurement result of the primary serving cell, regardless of any offset;

Ofp is the frequency specific offset of the primary serving cell, i.e. the offset frequency parameter (offsetFreq) defined in the EUTRA measurement configuration (measObjectEUTRA), which corresponds to the carrier frequency of the primary serving cell;

Ocp is the cell-specific offset of the primary serving cell, that is, the cell-specific offset parameter (cellIndividualOffset) defined in the EUTRA measurement configuration (measObjectEUTRA). If it is not configured for a pico cell, set Ocp to 0;

Hys is the hysteresis parameter of this event, that is, the hysteresis parameter defined for this event in EUTRA's report configuration (reportConfigEUTRA);

Off is the offset parameter of the event, that is, the a3 offset defined for the event in the EUTRA report configuration (reportConfigEUTRA). the

When receiving the measurement report triggered by the A3 event, the macro cell 10 classifies the mobility state of the user equipment according to the high-speed user equipment indicator therein. At the same time, the macro cell 10 will detect the type of the potential handover target cell, that is, the target cell is a macro cell or a pico cell, and the target cell will cause strong interference to the user equipment in the macro cell 10 . the

According to the mobile state level of the user equipment, the macro cell 10 will perform the following operations respectively:

1) For low-speed user equipment, the macro cell 10 will start a handover operation;

2) For the high-speed user equipment, the macro cell 10 will request the pico cell 20 to configure reserved resources for it, and it will not be handed over to the pico cell 20 any more. the

For the high-speed user equipment 3, the indication transceiving means 101 of the macro cell base station 10 sends a configuration request about configuring reserved resources for the high-speed user equipment 3 to the target pico cell, for example, instructing the transceiving means 101 to send an "ABS start request (ABS Turn-onRequest)" message. Preferably, when the macro cell 10 is currently providing a VoIP (Voice over Internet Protocol, VoIP) service for the high-speed user equipment 3, the ABS opening request may further include the next transmission time message of the VoIP service. the

The resource configuration device 201 of the pico cell base station 20 receives and responds to the configuration request sent by the macro cell 10, and configures reserved resources, such as ABS, for the high-speed user equipment 3 . According to the current ABS status of the pico cell 20, the resource allocation device 201 will respectively perform the following operations:

1) If the femto cell 20 is not currently configured with ABS and the high-speed user equipment 3 is using the VoIP service, the resource configuration device 201 determines the high-speed user equipment 3 according to the next transmission time message and the VoIP data transmission interval in the ABS activation request. Which subframe is used when user equipment 3 configures ABS;

2) If the pico cell 20 is not currently configured with ABS and the high-speed user equipment 3 does not use the VoIP service, the resource configuration device 201 can configure any subframe as a reserved subframe;

3) If the femto cell 20 is currently configured with ABS and the ABS activation request it receives is not for high-speed user equipment using VoIP services, the resource configuration device 201 does not need to additionally configure reserved subframes for the high-speed user equipment;

4) If the femtocell 20 has currently configured ABS and the ABS opening request it receives is for high-speed user equipment using VoIP services, the resource configuration device 201 reconfigures according to the next transmission time message of the high-speed user equipment 3 in the ABS opening request ABS. the

The resource indication means 202 sends indication information about reserved resources configured for the high-speed user equipment 3 to the macro cell 10 . For example, after the resource configuration unit 201 configures or reconfigures ABS for the high-speed user equipment 3, the resource indication unit 202 sends indication information of the configured ABS to the macro cell 10 through an existing X2ABS load-related message. the

After the indication transceiver device 101 of the macro cell base station 10 receives the indication information of the configured ABS from the pico cell 20, the communication device 102 resets the measurement configuration information through RRC signaling and makes corresponding scheduling decisions according to the configured ABS. the

Since ABS is used in the pico cell 20 to protect the high-speed user equipment 3 in the macro cell 10, when the high-speed user equipment 3 leaves the pico cell 20, ABS should be stopped to avoid waste of resources. The notification means 103 of the macro cell base station 10 detects whether the high-speed user equipment 3 is still in the coverage area of the pico cell 20, and when it leaves the pico cell 20, sends a notification message about stopping configuration of reserved resources to the pico cell 2, for example, to the pico cell 20. Cell 20 sends an "ABS Turn-off Request (ABS Turn-offRequest)" message. Here, there are at least two ways to detect whether the high-speed user equipment 3 is outside the coverage of the pico cell 20, so that the pico cell 20 stops configuring ABS for it:

1) When the high-speed user equipment 3 detects that the received RSRP (Reference Signal Receiving Power, reference signal receiving power) or RSRQ (Reference Signal Receiving Quality, reference signal receiving quality) is lower than the corresponding predetermined threshold, the high-speed user equipment 3 will report to the The macro cell 10 sends a specific message to indicate that the interference from the pico cell 20 is currently small, so that the pico cell 20 can be notified to stop the ABS configuration;

2) When the macro cell 10 receives a measurement report triggered by another A3 event, wherein the identity information of the target cell is different from the identity information of the pico cell in the measurement report of the A3 event triggered by the high-speed user equipment 3, the macro cell 10 knows that the high-speed user equipment 3 has left the pico cell 20, and may notify the pico cell 20 to stop ABS configuration. the

After the notification receiving means 203 of the pico cell base station 20 receives the ABS deactivation request sent by the macro cell 10, the allocation control means 204 decides whether to stop configuring ABS according to other received ABS activation requests. the

It should be noted that the present invention can be implemented in software and/or a combination of software and hardware, for example, it can be implemented by using an application specific integrated circuit (ASIC), a general purpose computer or any other similar hardware devices. the

The software program of the present invention can be executed by a processor to realize the steps or functions described above. Likewise, the software program (including associated data structures) of the present invention can be stored in a computer-readable recording medium such as RAM memory, magnetic or optical drive or floppy disk and the like. In addition, some steps or functions of the present invention may be implemented by hardware, for example, as a circuit that cooperates with a processor to execute each function or step. the

In addition, a part of the present invention can be applied as a computer program product, such as a computer program instruction. When it is executed by a computer, the method and/or technical solution according to the present invention can be invoked or provided through the operation of the computer. The program instructions for invoking the method of the present invention may be stored in a fixed or removable recording medium, and/or transmitted through broadcasting or data streams in other signal-carrying media, and/or stored in the in the working memory of the computer device on which the program instructions described above are executed. Here, according to one embodiment of the present invention, it comprises an apparatus comprising a memory for storing computer program instructions and a processor for executing the program instructions, wherein when the computer program instructions are executed by the processor , triggering the device to run the methods and/or technical solutions based on the aforementioned multiple embodiments of the present invention. the

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned. In addition, it is obvious that the word "comprising" does not exclude other elements or steps, and the singular does not exclude the plural. A plurality of units or devices stated in the system claims may also be realized by one unit or device through software or hardware. The words first, second, etc. are used to denote names and do not imply any particular order. the

Claims (15)

1. A method for eliminating interference between a pico cell and a high-speed user equipment for a heterogeneous network, wherein the heterogeneous network includes a macro cell and a pico cell, and both have the same geographical coverage area, and the high-speed user equipment Including user equipment whose speed exceeds a predetermined threshold, wherein the method includes: a. When the high-speed user equipment corresponding to the macro cell enters the coverage of the pico cell, the pico cell configures reserved resources for the high-speed user equipment, so as to eliminate interference between the pico cell and the high-speed user equipment; b. The macro cell communicates with the high-speed user equipment on the reserved resource. 2. The method according to claim 1, wherein said step a comprises: - the macro cell sends a configuration request about configuring reserved resources for the high-speed user equipment to the pico cell; - the pico cell configures the reserved resource for the high-speed user equipment according to the configuration request; - the pico cell sends indication information about the reserved resource to the macro cell. 3. The method according to claim 1, wherein said step a comprises: - the macro cell sends a handover request about the high-speed user equipment to the pico cell; - in response to the handover request, the pico cell configures the reserved resources for the high-speed user equipment; - the pico cell sends a handover decision message corresponding to the handover request to the macro cell, where the handover decision message includes indication information of the reserved resource. 4. The method according to any one of claims 1 to 3, wherein said step b comprises: - the macro cell reconfigures the user equipment according to the reserved resources to communicate with the user equipment on the reserved resources. 5. The method according to any one of claims 1 to 4, wherein the method further comprises: - when the high-speed user equipment is outside the coverage of the pico cell, the macro cell sends a notification message about stopping configuration of the reserved resources to the pico cell; - The pico cell stops configuring the reserved resources according to the notification message. 6. An apparatus for eliminating interference between a pico cell and high-speed user equipment in a heterogeneous network, wherein the heterogeneous network includes the pico cell and a macro cell having the same geographical coverage area as the pico cell, and the high-speed user equipment The device includes user equipment whose speed exceeds a predetermined threshold, wherein the means includes: A resource configuration device, configured to configure reserved resources for the high-speed user equipment when the high-speed user equipment corresponding to the macro cell enters the coverage of the pico cell, so as to eliminate interference between the pico cell and the high-speed user equipment ; Resource indication means, configured to send indication information about the reserved resource to the macro cell, so that the macro cell communicates with the high-speed user equipment on the reserved resource. 7. The device according to claim 6, wherein the resource configuration device is used for: - receiving a configuration request from the macro cell for configuring reserved resources for the high-speed user equipment; - configuring the reserved resource for the high-speed user equipment according to the configuration request. 8. The device according to claim 6, wherein the resource configuration device is used for: - receiving a handover request for said high-speed user equipment from the macro cell; - configuring said reserved resources for said high-speed user equipment in response to said handover request; Wherein, the resource indication device is used for: - sending a handover decision message corresponding to the handover request to the macro cell, where the handover decision message includes indication information of the reserved resource, so that the macro cell communicates with the high-speed user equipment on the reserved resource . 9. The device according to any one of claims 6 to 8, wherein the device comprises: Notification receiving means, configured to receive a notification message about stopping configuration of the reserved resources from the macro cell when the high-speed user equipment is outside the coverage of the pico cell; The configuration control device is configured to stop configuration of the reserved resources according to the notification message. 10. An apparatus for assisting a pico cell in a heterogeneous network to eliminate interference with high-speed user equipment, wherein the heterogeneous network includes the macro cell and a pico cell having the same geographical coverage as the macro cell, so The high-speed user equipment includes user equipment whose speed exceeds a predetermined threshold, wherein the apparatus includes: an instruction transceiving means, configured to receive, from the pico cell, indication information of reserved resources configured for the high speed user equipment when the high speed user equipment corresponding to the macro cell enters the coverage of the pico cell; Communication means, configured to communicate with the high-speed user equipment on the reserved resource. 11. The device according to claim 10, wherein the indication transceiving means is used for: - when the high-speed user equipment corresponding to the macro cell enters the coverage of the pico cell, sending a configuration request about configuring reserved resources for the high-speed user equipment to the pico cell; - receiving indication information of reserved resources configured by the pico cell for the high-speed user equipment from the pico cell. 12. The device according to claim 10, wherein the indication transceiving means is used for: - sending a handover request for said high-speed user equipment to the pico cell; - receiving, from the pico cell, a handover decision message corresponding to the handover request, the handover decision message including indication information of reserved resources configured by the pico cell for the high-speed user equipment. 13. The device according to any one of claims 10 to 12, wherein the communication device is configured to: - According to the reserved resources, reconfiguring the user equipment to communicate with the user equipment on the reserved resources. 14. The device according to any one of claims 10 to 13, wherein the device further comprises: Notifying means, configured to send a notification message about stopping configuration of the reserved resources to the pico cell when the high-speed user equipment is outside the coverage of the pico cell. 15. A system for eliminating interference between a pico cell and a high-speed user equipment in a heterogeneous network, wherein the heterogeneous network includes a macro cell and a pico cell, both of which have the same geographic coverage area, and the high-speed user equipment Including user equipment whose speed exceeds a predetermined threshold, wherein the system includes the device for eliminating interference between the pico cell in a heterogeneous network and high-speed user equipment according to any one of claims 6 to 9, and The device for assisting a pico cell in a macro cell in a heterogeneous network to eliminate interference with high-speed user equipment as claimed in any one of claims 10 to 14.