WO2015052582A2

WO2015052582A2 - Method of enforcing user equipment-ambr

Info

Publication number: WO2015052582A2
Application number: PCT/IB2014/002598
Authority: WO
Inventors: Yun DENG; Pingping Wen; Chandrika Worrall
Original assignee: Alcatel Lucent
Priority date: 2013-10-11
Filing date: 2014-10-13
Publication date: 2015-04-16
Also published as: CN104581677A; WO2015052582A3

Abstract

The invention provides a method of enforcing user equipment- AMBR. According to an embodiment of the present invention, it is provided a method, in a master eNB, of enforcing uplink user equipment- AMBR and downlink user equipment- AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: b. transmitting a first message to the secondary eNB, the first message being used to assist the secondary eNB in determining uplink AMBR of the small cell and downlink AMBR of the small cell.

Description

Method of Enforcing User Equipment- AMBR

Field of the invention

The present disclosure relates to mobile communication technology and particularly to a method of enforcing user equipment- AMBR.

Background of the invention

Due to the gain for the capacity improvement brought by the low power node, there are big interests on small cell deployments and enhancements. In 3 GPP R12, one new Study Item "Small Cell Enhancements for E-UTRA and E-UTRAN - Higher-layer aspects" has been approved and one important point is to support the dual connectivity on macro and small cell layers. Figure 1 illustrates dual connectivity for a user equipment (UE) with a master eNB (MeNB) and a secondary eNB (SeNB).

According to TS23.401 , each UE in state EMM-REGISTERED is associated with the following bearer aggregate level QoS parameter: per UE Aggregate Maximum Bit Rate (UE-AMBR), which includes uplink UE-AMBR and downlink UE-AMBR.

The UE AMBR is limited by a subscription parameter stored in the

HSS. The Mobile Management Entity (MME) shall set the UE-AMBR to the sum of the APN AMBR of all active APNs up to the value of the subscribed UE-AMBR. The UE-AMBR limits the aggregate bit rate that can be expected to be provided across all non-Guarantee Bit Rate (GBR) bearers of a UE. Each of those non-GBR bearers could potentially utilize the entire UE-AMBR, e.g. when the other non-GBR bearers do not carry any traffic.

In the past, UE only has one RRC connection with one serving eNB. This serving eNB should enforce the UE-AMBR in uplink and downlink. But when UE has established dual connectivity with the MeNB and the SeNB simultaneously, how to enforce UE-AMBR is necessary but has not been discussed yet.

Summary of the invention

In view of this, this application provides feasible solutions to enforce UE-AMBR in the situation of dual connectivity.

According to a first aspect of the invention, there is proposed a method, in a master eNB, of enforcing uplink user equipment- AMBR and downlink user equipment- AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: b. transmitting a first message to the secondary eNB, the first message being used to assist the secondary eNB in determining uplink AMBR of the small cell and downlink AMBR of the small cell.

According to a second aspect of the invention, there is proposed a method, in a secondary eNB, of enforcing uplink user equipment- AMBR and downlink user equipment-AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: A. receiving a first message from the master eNB or core network, the first message being used to assist the secondary eNB in determining uplink AMBR of the small cell and downlink AMBR of the small cell; and B. scheduling the user equipment with the uplink AMBR of the small cell and the downlink AMBR of the small cell at least based on the first message.

According to a third aspect of the invention, there is proposed a method, in a master eNB, of enforcing downlink user equipment-AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: XI . transmitting data packets of non-GBR data radio bearers with a first bit rate to the secondary eNB; X2. determining downlink AMBR of the macro cell, wherein the downlink AMBR of the macro cell equals difference between the downlink user equipment-AMBR and the first bit rate; and X3. scheduling the user equipment with the downlink AMBR of the macro cell.

According to a fourth aspect of the invention, there is proposed a method, in a secondary eNB, of enforcing downlink user equipment-AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: Tl . receiving data packets of non-GBR data radio bearers transmitted with a first bit rate from the master eNB; and T2. determining the first bit rate as downlink AMBR of the small cell, and scheduling the user equipment with the downlink AMBR of the small cell.

According to a fifth aspect of the invention, there is proposed a method, in a master eNB, of enforcing uplink user equipment-AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: i. detecting a first uplink bit rate of data packets of non-GBR data radio bearers from the user equipment to the secondary eNB; ii. obtaining a second uplink bit rate by summing the first uplink bit rate with uplink AMBR of the macro cell; and iii. comparing the second uplink bit rate with uplink user equipment- AMBR, if the second uplink bit rate is greater than the uplink user equipment-AMBR, transmitting a request message to the secondary eNB, the request message indicating the secondary eNB to decrease the first uplink bit rate.

According to a sixth aspect of the invention, there is proposed a method, in a secondary eNB, of enforcing uplink user equipment-AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: Dl . receiving a request message from the macro eNB, the request message indicating the secondary eNB to decrease a first uplink bit rate of data packets of non-GBR data radio bearers from the user equipment to the secondary eNB; and D2. decreasing the first uplink bit rate, and scheduling the user equipment with the decreased first uplink bit rate.

According to a seventh aspect of the invention, there is proposed a method, in a core network, of enforcing uplink user equipment-AMBR and downlink user equipment-AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: Gl . determining uplink AMBR of the macro cell and downlink AMBR of the macro cell for the macro cell, and determining uplink AMBR of the small cell and downlink AMBR of the small cell for the small cell; and G2. transmitting a first instruction message to the macro eNB, which indicates the uplink AMBR of the macro cell and the downlink AMBR of the macro cell, and transmitting a second instruction message to the secondary eNB, which indicates the uplink AMBR of the small cell and the downlink AMBR of the small cell; G3. receiving an E-RAB message from the macro eNB, which indicates whether amount of non-GBR data radio bearers offloaded to the secondary eNB has changed; and G4. implementing the steps Gl and G2 again based on amount of non-GBR data radio bearers offloaded to the secondary eNB after change, when the amount of non-GBR data radio bearers offloaded to the secondary eNB has changed.

According to an eighth aspect of the invention, there is proposed a method, in a master eNB, of enforcing uplink user equipment- AMBR and downlink user equipment- AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps: - receiving a first instruction message from a core network, which indicates the uplink AMBR of the macro cell and the downlink AMBR of the macro cell; and - scheduling the user equipment with the uplink AMBR of the macro cell and the downlink AMBR of the macro cell.

Through the preferable embodiments of the present invention, the uplink and downlink UE-AMBR can be enforced in the situation of dual connectivity. Herein, both the MeNB and the SeNB can schedule the UE with appropriate uplink AMBR and downlink AMBR.

The respective aspects of the invention will become more apparent from the following description of particular embodiments.

Brief description of drawings

Other features, objects and advantages of the invention will become more apparent upon review of the following detailed description of non-limiting embodiments taken with reference to the drawings in which: Fig. l illustrates a UE having dual connectivity with a MeNB and a SeNB according to an embodiment of the present invention;

Fig. 2 illustrates a flow chart of a method of enforcing UE-AMBR according to an embodiment of the present invention;

Fig. 3 illustrates a flow chart of a method of enforcing downlink UE-AMBR according to an embodiment of the present invention;

Fig. 4 illustrates a flow chart of a method of enforcing uplink UE-AMBR according to an embodiment of the present invention; and

Fig. 5 illustrates a flow chart of a method of enforcing UE-AMBR according to another embodiment of the present invention.

In the drawings, identical or like reference numerals denote identical or corresponding components or features throughout the different figures.

Detailed description of embodiments

Fig. 2 illustrates a flow chart of a method of enforcing UE-AMBR according to an embodiment of the present invention.

As shown in Fig.2, in step S201, the MeNB transmits a first message to the SeNB, the first message being used to assist the SeNB in determining uplink AMBR of the small cell and downlink AMBR of the small cell.

In one embodiment of the present invention, the first message includes the uplink AMBR of the small cell and the downlink AMBR of the small cell. In this situation, before step S201, the MeNB can allocate the uplink AMBR of the small cell and the downlink AMBR of the small cell for the SeNB according to a predetermined condition. Herein, the predetermined condition includes, but not limited to, relationship between the amount of non-GBR data radio bearers offloaded to the SeNB and total amount of non-GBR data radio bearers; relationship between QoS of non-GBR data radio bearers offloaded to the SeNB and QoS of non-GBR data radio bearers not offloaded to the SeNB; channel status in the macro cell and channel status in the small cell; backhaul status (for example, available backhaul transmission rate); and load status of the macro cell and load status of the small cell, for example.

Herein, the total amount of non-GBR data radio bearers refers to the total amount of non-GBR data radio bearers established by UE. Herein, a part of non-GBR data radio bearers is offloaded to the SeNB. The SeNB provides service for those data radio bearers. Other data radio bearers will be retained at the MeNB, that is, not offloaded. The MeNB provides service for those data radio bearers.

In another embodiment of the present invention, the first message includes the uplink UE-AMBR and the downlink UE-AMBR and total amount of non-GBR data radio bearers.

And when the total amount of the non-GBR data radio bearers is updated and/or the amount of non-GBR data radio bearers offloaded to the SeNB is updated, the MeNB will transmit a second message to the SeNB, the second message including the updated total amount of the non-GBR data radio bearers and/or the updated amount of non-GBR data radio bearers offloaded to the SeNB.

As shown in Fig.2, in step S202, the SeNB schedules the UE with the uplink AMBR of the small cell and the downlink AMBR of the small cell at least based on the first message.

More specifically, in the situation in which the first message includes the uplink AMBR of the small cell and the downlink AMBR of the small cell, the SeNB can schedule the UE immediately based on the uplink AMBR of the small cell and the downlink AMBR of the small cell in the first message. More clearly, for example, the SeNB obtains the downlink AMBR of the small cell, when the SeNB allocates the downlink transmission resource, it needs to calculate the bit rate for data transmission, which should not be greater than the downlink AMBR of the small cell. Of course, in other embodiments of the present invention, the SeNB will also consider channel quality and other factors. Herein, scheduling the UE based on the uplink AMBR of the small cell and the downlink AMBR of the small cell means that the uplink bit rate for scheduling the UE is not greater than uplink AMBR, and the downlink bit rate for scheduling the UE is not greater than downlink AMBR.

Alternatively, in the situation in which the first message includes the uplink UE-AMBR, the downlink UE-AMBR and total amount of non-GBR data radio bearers, since the SeNB definitely has known the amount of the non-GBR data radio bearers offloaded to the SeNB, the SeNB will determine the uplink AMBR of the small cell and the downlink AMBR of the small cell through the following relationship.

Specifically, the SeNB determines the uplink AMBR of the small cell based on uplink UE-AMBR, the total amount of the non-GBR data radio bearers and the amount of non-GBR data radio bearers offloaded to the SeNB.

For example, the uplink AMBR of the small cell is determined based on the following rule.

uplink AMBR of the small cell = uplink UE-AMBR * (amount of non-GBR data radio bearers offloaded to the SeNB/ total amount of the non-GBR data radio bearers)

For example, the amount of the non-GBR data radio bearers established by the UE is 4, the amount of non-GBR data radio bearers offloaded to the SeNB is 3, then the uplink AMBR of the small cell could be determined through the following equation:

uplink AMBR of the small cell = uplink UE-AMBR * (3/4)

For downlink AMBR of the small cell, it can be determined by applying a similar method.

That is, based on the following rule:

downlink AMBR of the small cell = downlink UE-AMBR * (amount of non-GBR data radio bearers offloaded to the SeNB/ total amount of the non-GBR data radio bearers)

Herein, if the SeNB receives the abovementioned second message from the MeNB later, the SeNB will implement the abovementioned rule based on the updated total amount of the non-GBR data radio bearers and/or the updated amount of non-GBR data radio bearers offloaded to the SeNB in the second message, for determining the uplink AMBR of the small cell and the downlink AMBR of the small cell currently.

Now return to Fig.2, in step S203, the MeNB determines uplink AMBR of the macro cell and downlink AMBR of the macro cell. Herein, the MeNB can determine the uplink AMBR of the macro cell and the downlink AMBR of the macro cell based on the following relationship: uplink AMBR of the macro cell + uplink AMBR of the small cell = uplink UE-AMBR; and

downlink AMBR of the macro cell + downlink AMBR of the small cell = downlink UE-AMBR

That is, herein, the uplink AMBR of the macro cell equals difference between the uplink UE-AMBR and the uplink AMBR of the small cell, and the downlink AMBR of the macro cell equals difference between the downlink UE-AMBR and the downlink AMBR of the small cell.

Then, in step 204, the MeNB schedules the UE with the uplink AMBR of the macro cell and the downlink AMBR of the macro cell. Similarly, this means the uplink bit rate used by the MeNB to schedule the UE is not greater than the uplink AMBR, and the downlink bit rate used by the MeNB to schedule the UE is not greater than the downlink AMBR.

Now, as shown in Fig. 2, Steps S205 to S210 shows the subsequent coordination between the SeNB and the MeNB to determine the uplink AMBR and the downlink AMBR for the respective cell. The above coordination progress could be implemented when the condition, such as the channel condition, load status and/or non-GBR data radio bearers and etc. changes.

In step S205, the SeNB will determine recommended uplink AMBR of the small cell and recommended downlink AMBR of the small cell, or determine to decrease or increase the uplink AMBR of the small cell and the downlink AMBR of the small cell, according to a predetermined condition. Herein, the SeNB needs to know the uplink UE-AMBR and downlink UE-AMBR.

Further, the predetermined condition can include, but not limited into, channel status in the small cell (referring to the channel status in the small cell where the UE is located in), load status of the small cell, transmission status of non-GBR data radio bearers offloaded to the SeNB, backhaul status, and QoS of non-GBR data radio bearers offloaded to the SeNB.

For example, if the channel status of the small cell is good and a lot of data need to be transmitted in the small cell, the SeNB will determine to recommend a higher uplink AMBR of the small cell and a higher downlink AMBR of the small cell, or determine to increase the uplink AMBR of the small cell and the downlink AMBR of the small cell. If the channel status of the small cell is not good, or the backhaul is in a higher load status, the SeNB will determine to recommend a lower uplink AMBR of the small cell and a lower downlink AMBR of the small cell, or determine to decrease the uplink AMBR of the small cell and the downlink AMBR of the small cell.

In step S206, the SeNB transmits a request message to the MeNB. This request message includes the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell, or includes indication that the SeNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell.

In step S207, the MeNB determines whether to accept the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell, or determines whether to accept the indication that the SeNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell. This could be implemented according to the abovementioned predetermined condition, for example. Herein, the MeNB can also reconfigure new uplink AMBR of the small cell and new downlink AMBR of the small cell.

Then, in step S207, the MeNB transmits a response message to the SeNB.

In one embodiment of the present invention, the response message indicates whether the MeNB accepts the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell.

Alternatively, the response message indicates whether the MeNB accepts the indication that the SeNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell.

Alternatively, the response message indicates the new uplink AMBR of the small cell and the new downlink AMBR of the small cell configured by the MeNB .

In step S208, the SeNB will conduct the corresponding procedure based on the response message.

Specifically, the SeNB schedules the UE with the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell, if the response message indicates that the MeNB accepts the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell.

Alternatively, the SeNB schedules the UE with the new uplink AMBR of the small cell and the new downlink AMBR of the small cell, if the response message indicates the new uplink AMBR of the small cell and the new downlink AMBR of the small cell configured by the MeNB.

Identically, in the side of the MeNB, in step 209, the MeNB determines a first uplink AMBR of the macro cell and a first downlink AMBR of the macro cell, if the MeNB accepts the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell or the MeNB configures a new uplink AMBR of the small cell and a new downlink AMBR of the small cell. Herein, the first uplink AMBR of the macro cell and the first downlink AMBR of the macro cell is determined still according to the abovementioned relationship. Specifically, the first uplink AMBR of the macro cell equals difference between the uplink UE-AMBR and the recommended uplink AMBR or the new uplink AMBR of the small cell, the first downlink AMBR of the macro cell equals difference between the downlink UE-AMBR and the recommended downlink AMBR or the new downlink AMBR of the small cell.

Then, in step S210, the MeNB schedules the UE with the first uplink AMBR of the macro cell and the first downlink AMBR of the macro cell determined in step S209. Thereby, step 205 to step 201 finishes the coordination procedure started by the SeNB. However, in other alternative embodiments of the present invention, when the channel condition changes, non-GBR data radio bearers change (the MeNB adds or releases non-GBR data radio bearers established by the UE for the SeNB, for example), the MeNB can reconfigure the uplink AMBR and the downlink AMBR for the SeNB.

It shall also be noted that, the number of the macro cell served by the MeNB could be one or more, the MeNB can use carrier aggregation to serve the UE. The number of the small cell served by the SeNB could be one or more, the SeNB can use carrier aggregation to serve the UE. In this scenario, when the SeNB knows the uplink AMBR of the small cell and the downlink AMBR of the small cell, the SeNB needs to guarantee that the downlink bit rate used to schedule the UE (the sum of the respective small cells) is not greater than the downlink AMBR of the small cell. This is also suitable for the uplink. Also, this is also suitable for the MeNB.

Fig. 3 illustrates a flow chart of a method of enforcing downlink UE-AMBR according to an embodiment of the present invention.

As shown in Fig.3, in step S301 , the MeNB transmits data packets of non-GBR data radio bearers with a first bit rate to the SeNB. This first bit rate could be constant or variable.

Then, in step S302, the SeNB determines the first bit rate as downlink AMBR of the small cell, and schedules the UE with the downlink AMBR of the small cell. In the situation in which the first bit is variable, the SeNB can obtain a maximum value of this variable first bit rate (obtain a maximum valve in a predetermined time period, for example), and schedule the UE with a downlink bit rate, which is not greater than this maximum value.

In step S303, the MeNB determines downlink AMBR of the macro cell. As similar with the abovementioned, the downlink AMBR of the macro cell equals difference between the downlink UE-AMBR and the first bit rate.

Then, in step S304, the MeNB schedules the UE with the downlink AMBR of the macro cell.

Fig.4 illustrates a flow chart of a method of enforcing uplink UE-AMBR according to an embodiment of the present invention.

As shown in Fig.4, in step S401, the MeNB detects a first uplink bit rate of data packets of non-GBR data radio bearers from the UE to the SeNB. Specifically, the MeNB obtains this first uplink bit rate through detecting the rate of the data packets of the data radio bearers sent by the SeNB to the MeNB. Alternatively, the MeNB can obtain this first uplink bit rate from the SeNB.

Then, in step S402, the MeNB obtains a second uplink bit rate by summing the first uplink bit rate with uplink AMBR of the macro cell.

Then, in step S403, the MeNB compares the second uplink bit rate with uplink UE-AMBR. If the second uplink bit rate is greater than the uplink UE-AMBR, the MeNB transmits a request message to the SeNB, the request message indicating the SeNB to decrease the first uplink bit rate.

In step S404, the SeNB decreases the first uplink bit rate, and schedules the UE with the decreased first uplink bit rate.

Fig. 5 illustrates a flow chart of a method of enforcing UE-AMBR according to another embodiment of the present invention. Different from the abovementioned embodiments, this embodiment involves a MeNB, a SeNB and a core network. Herein, the MME module in the core network will be applied.

As shown in Fig. 5, in step S501, the core network determines uplink AMBR of the macro cell and downlink AMBR of the macro cell for the macro cell, and determines uplink AMBR of the small cell and downlink AMBR of the small cell for the small cell. Herein, the core network can also allocate the abovementioned uplink AMBR and downlink AMBR based on the total amount of non-GBR data radio bearers established by the UE and the amount of non-GBR data radio bearers offloaded to the SeNB and/or the load status of the macro cell and the small cell.

In step S502, the core network transmits a first instruction message to the MeNB, which indicates the uplink AMBR of the macro cell and the downlink AMBR of the macro cell, and transmits a second instruction message to the SeNB, which indicates the uplink AMBR of the small cell and the downlink AMBR of the small cell.

Further, the MeNB and the SeNB will schedule the UE based on the corresponding bit rate, respectively.

In step S503, the MeNB transmits an E-RAB message to the core network. This E-RAB message can include at least one of the amount of the non-GBR data radio bearers offloaded to the SeNB and the amount of the non-GBR data radio bearers. When this E-RAB message includes the amount of the non-GBR data radio bearers offloaded to the SeNB, it indicates that the amount of the non-GBR data radio bearers offloaded to the SeNB has changed.

In step S504, the core network implements the steps S501 and S502 again based on amount of non-GBR data radio bearers offloaded to the SeNB after change, when the amount of non-GBR data radio bearers offloaded to the SeNB has changed. That is, the uplink AMBR and the downlink AMBR have been reconfigured for the macro cell and the small cell.

Similarly, then, the MeNB and the SeNB will schedule the UE based on the corresponding bit rate, respectively.

It shall be appreciated that the foregoing embodiments are merely illustrative but will not limit the invention. Any technical solutions without departing from the spirit of the invention shall fall into the scope of invention, including that different technical features, methods appearing in different embodiments are used to combine to advantage.

Claims

1. A method, in a master eNB, of enforcing uplink user equipment-AMBR and downlink user equipment-AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

b. transmitting a first message to the secondary eNB, the first message being used to assist the secondary eNB in determining uplink AMBR of the small cell and downlink AMBR of the small cell.

2. A method according to claim 1 , wherein

the first message includes the uplink AMBR of the small cell and the downlink AMBR of the small cell; before the step b, the method includes step a:

a. allocating the uplink AMBR of the small cell and the downlink AMBR of the small cell for the secondary eNB according to a predetermined condition;

or, the first message includes the uplink user equipment-AMBR, the downlink user equipment-AMBR and total amount of non-GBR data radio bearers, and when the total amount of the non-GBR data radio bearers is updated and/or amount of non-GBR data radio bearers offloaded to the secondary eNB is updated, the step b further includes: transmitting a second message to the secondary eNB, the second message including the updated total amount of the non-GBR data radio bearers and/or the updated amount of non-GBR data radio bearers offloaded to the secondary eNB.

3. A method according to claim 2, wherein the predetermined condition includes ate least one of the followings:

- relationship between the amount of the non-GBR data radio bearers offloaded to the secondary eNB and the total amount of non-GBR data radio bearers;

- relationship between QoS of the non-GBR data radio bearers offloaded to the secondary eNB and QoS of non-GBR data radio bearers not offloaded to the secondary eNB;

- channel status in the macro cell and channel status in the small cell;

- backhaul status; and

- load status of the macro cell and load status of the small cell.

4. A method according to claim 1 , wherein the method further comprises steps s i and s2:

s i . determining uplink AMBR of the macro cell and downlink AMBR of the macro cell, wherein the uplink AMBR of the macro cell equals difference between the uplink user equipment-AMBR and the uplink AMBR of the small cell, the downlink AMBR of the macro cell equals difference between the downlink user equipment-AMBR and the downlink AMBR of the small cell; and

s2. scheduling the user equipment with the uplink AMBR of the macro cell and the downlink AMBR of the macro cell.

5. A method according claim 1 , wherein the method further comprises steps c to g:

c. receiving a request message from the secondary eNB, the request message including uplink AMBR of the small cell recommended by the secondary eNB and downlink AMBR of the small cell recommended by the secondary eNB, or the request message including the indication that the secondary eNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell;

d. determining whether to accept the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell, or determining whether to accept the indication that the secondary eNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell;

e. transmitting a response message to the small cell, the response message indicating whether the master eNB accepts the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell, or the response message indicating whether the master eNB accepts the indication that the secondary eNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell, or the response message indicating new uplink AMBR of the small cell and new downlink AMBR of the small cell configured by the master eNB;

f. determining a first uplink AMBR of the macro cell and a first downlink AMBR of the macro cell, if the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell is accepted or the new uplink AMBR of the small cell and the new downlink AMBR of the small cell is configured, wherein the first uplink AMBR of the macro cell equals difference between the uplink user equipment-AMBR and the recommended uplink AMBR or the new uplink AMBR of the small cell, the first downlink AMBR of the macro cell equals difference between the downlink user equipment-AMBR and the recommended downlink AMBR or the new downlink AMBR of the small cell; and

g. scheduling the user equipment with the first uplink AMBR of the macro cell and the first downlink AMBR of the macro cell.

6. A method, in a secondary eNB, of enforcing uplink user equipment-AMBR and downlink user equipment-AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

A. receiving a first message from the master eNB or core network, the first message being used to assist the secondary eNB in determining uplink AMBR of the small cell and downlink AMBR of the small cell; and

B. scheduling the user equipment with the uplink AMBR of the small cell and the downlink AMBR of the small cell at least based on the first message.

7. A method according to claim 6, wherein the first message includes the uplink AMBR of the small cell and the downlink AMBR of the small cell; or

the first message includes the uplink user equipment-AMBR and the downlink user equipment-AMBR and total amount of non-GBR data radio bearers, the step B further includes:

B 1. determining the uplink AMBR of the small cell based on the uplink user equipment-AMBR, the total amount of the non-GBR data radio bearers and amount of non-GBR data radio bearers offloaded to the secondary eNB, and determining the downlink AMBR of the small cell based on the downlink user equipment-AMBR, the total amount of the non-GBR data radio bearers and amount of non-GBR data radio bearers offloaded to the secondary eNB; and

B2. scheduling the user equipment with the uplink AMBR of the small cell and the downlink AMBR of the small cell.

8. A method according to claim 6 or 7, wherein in the situation in which the first message is received from the macro eNB, the method further comprises the following steps:

C. determining recommended uplink AMBR of the small cell and recommended downlink AMBR of the small cell, or determining to decrease or increase the uplink AMBR of the small cell and the downlink AMBR of the small cell, according to a predetermined condition;

D. transmitting a request message to the macro eNB, the request message including the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell, or including indication that the secondary eNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell;

E. receiving a response message from the macro eNB, the response message indicating whether the master eNB accepts the recommended uplink

AMBR of the small cell and the recommended downlink AMBR of the small cell, or the response message indicating whether the master eNB accepts the indication that the secondary eNB requests to decrease and increase the uplink AMBR of the small cell and the downlink AMBR of the small cell, or the response message indicating new uplink AMBR of the small cell and new downlink AMBR of the small cell configured by the master eNB;

F. scheduling the user equipment with the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell, if the response message indicates that the macro eNB accepts the recommended uplink AMBR of the small cell and the recommended downlink AMBR of the small cell; scheduling the user equipment with the new uplink AMBR of the small cell and the new downlink AMBR of the small cell, if the response message indicates the new uplink AMBR of the small cell and the new downlink AMBR of the small cell configured by the macro eNB.

9. A method according to claim 8, wherein the predetermined condition includes ate least one of the followings:

- channel status in the small cell;

- load status of the small cell;

- transmission status of the non-GBR data radio bearers offloaded to the secondary eNB ;

- backhaul status; and

- QoS of the non-GBR data radio bearers offloaded to the secondary eNB.

10. A method, in a master eNB, of enforcing downlink user equipment- AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

XI . transmitting data packets of non-GBR data radio bearers with a first bit rate to the secondary eNB;

X2. determining downlink AMBR of the macro cell, wherein the downlink AMBR of the macro cell equals difference between the downlink user equipment- AMBR and the first bit rate; and

X3. scheduling the user equipment with the downlink AMBR of the macro cell.

11. A method, in a secondary eNB, of enforcing downlink user equipment- AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

Tl . receiving data packets of non-GBR data radio bearers transmitted with a first bit rate from the master eNB ; and

T2. determining the first bit rate as downlink AMBR of the small cell, and scheduling the user equipment with the downlink AMBR of the small cell.

12. A method, in a master eNB, of enforcing uplink user equipment- AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

i. detecting a first uplink bit rate of data packets of non-GBR data radio bearers from the user equipment to the secondary eNB ;

ii. obtaining a second uplink bit rate by summing the first uplink bit rate with uplink AMBR of the macro cell; and

iii. comparing the second uplink bit rate with uplink user equipment- AMBR, if the second uplink bit rate is greater than the uplink user equipment-AMBR, transmitting a request message to the secondary eNB, the request message indicating the secondary eNB to decrease the first uplink bit rate.

13. A method, in a secondary eNB, of enforcing uplink user equipment-AMBR, which is used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

Dl . receiving a request message from the macro eNB, the request message indicating the secondary eNB to decrease a first uplink bit rate of data packets of non-GBR data radio bearers from the user equipment to the secondary eNB; and

D2. decreasing the first uplink bit rate, and scheduling the user equipment with the decreased first uplink bit rate.

14. A method, in a core network, of enforcing uplink user equipment-AMBR and downlink user equipment-AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

Gl . determining uplink AMBR of the macro cell and downlink AMBR of the macro cell for the macro cell, and determining uplink AMBR of the small cell and downlink AMBR of the small cell for the small cell; and

G2. transmitting a first instruction message to the macro eNB, which indicates the uplink AMBR of the macro cell and the downlink AMBR of the macro cell, and transmitting a second instruction message to the secondary eNB, which indicates the uplink AMBR of the small cell and the downlink

AMBR of the small cell;

G3. receiving an E-RAB message from the macro eNB, which indicates whether amount of non-GBR data radio bearers offloaded to the secondary eNB has changed; and

G4. implementing the steps Gl and G2 again based on amount of non-GBR data radio bearers offloaded to the secondary eNB after change, when the amount of non-GBR data radio bearers offloaded to the secondary eNB has changed.

15. A method, in a master eNB, of enforcing uplink user equipment-AMBR and downlink user equipment-AMBR, which are used for non-GBR data radio bearers established by a user equipment, in a dual connectivity-based communication scenario, wherein the user equipment, the master eNB and a secondary eNB form dual connectivity, the master eNB serves a macro cell, and the secondary eNB serves a small cell, the method comprises following steps:

- receiving a first instruction message from a core network, which indicates the uplink AMBR of the macro cell and the downlink AMBR of the macro cell; and

- scheduling the user equipment with the uplink AMBR of the macro cell and the downlink AMBR of the macro cell.