CN102843730B

CN102843730B - Method for transmitting data, network element side and UE (User Equipment) in joint transmission

Info

Publication number: CN102843730B
Application number: CN201110171606.8A
Authority: CN
Inventors: 邓云; 艾建勋
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2011-06-23
Filing date: 2011-06-23
Publication date: 2017-05-03
Anticipated expiration: 2031-06-23
Also published as: WO2012174889A1; CN102843730A

Abstract

The invention discloses a method for sending downlink data in joint transmission. The method comprises the following steps of distributing a data transmission protocol framework of a data package by adopting an MAC (Media Access Control) layer according to an anchor point network element and a non-anchor point network element which are involved in the joint transmission, wherein the MAC layer of the data transmission protocol framework comprises an MAC-1 entity and an MAC-2 entity which are positioned in the anchor point network element and an MAC-2 entity which is positioned in the non-anchor point network element; and distributing a downlink data package to each MAC-2 entity by the MAC-1 entity positioned in the anchor point network element during data joint transmission, and sending the received downlink data package to UE (User Equipment) by each MAC-2 entity which receives the downlink data package. The invention also simultaneously discloses a receiving method of the downlink data, a sending and receiving method of uplink data, a corresponding network element side and the UE in the joint transmission. According to the scheme disclosed by the invention, the data transmission problem in a joint transmission way is solved, the reasonable data distribution at the network element side is facilitated, and the data transmission rate of the UE is increased.

Description

Method for data transmission in joint transmission, network element side and user equipment

Technical Field

The present invention relates to the third generation partnership project (3GPP) technology in the field of communications, and in particular, to a method, a network element side, and a user equipment for data transmission in joint transmission.

Background

As shown in fig. 1, an architecture of an existing 3GPP Access System includes a Radio Access network portion and a core network portion, where the Radio Access network portion includes a geran (gsm EDGE Radio Access network), a Universal Mobile Telecommunications System (UMTS) Access network, and a Long Term Evolution (LTE) Access network. The access networks of GERAN and UMTS are connected with the GPRS service Support Node (SGSN) of the core network element, and the access network of LTE is connected with the Mobility Management Entity (MME) of the core network element. GERAN refers to a Base Station Subsystem (BSS), which includes a Base Station Controller (BSC) and a Base Station (BS); the access Network element of the UMTS includes a Radio Network Controller (RNC) and a base station (NodeB); the access network element of LTE is an Evolved base station (eNB, Evolved NodeB). In order to ensure that a connected User Equipment (UE) can move freely between different access systems, an S3 interface is established between an SGSN and an MME, and the interface can implement handover of the UE between different access systems.

In order to achieve higher transmission rate, 3GPP proposes a Carrier Aggregation (Carrier Aggregation) technical solution, which uses multiple carriers to simultaneously serve user equipment. Existing carrier aggregation schemes mainly utilize multiple carriers in a single system to provide services for user equipment simultaneously, such as UMTS, which utilizes 2 or more carriers (each carrier may be an independent cell or a resource carrier that only provides data transmission) to simultaneously maintain communication with the user equipment, or LTE, which utilizes 2 or more carriers to simultaneously maintain communication with the user equipment. However, in practical networks, due to the limitation of the number of carrier frequencies, some mobile operators do not have enough frequencies to deploy multiple UMTS and LTE systems simultaneously, and the mobile operators can adjust the number of UMTS and LTE carriers according to the number of user equipment accessing the network. Since the UMTS system and the LTE system coexist for a long time, when the capacity (the limitation of carrier frequency) of a single system is not enough to provide a high transmission rate, a scheme of joint transmission using different systems is conceived, which may also be referred to as cross-system carrier aggregation, as shown in fig. 2, a user equipment simultaneously uses two access technologies to establish two radio links for transmitting data, one is a radio link between the user equipment and an evolved base station of LTE, and the other is a radio link between the user equipment and a base station and an RNC in the UMTS system, which not only can obtain higher throughput, but also can achieve better load balancing effect. Before the scheme of joint transmission is not adopted, the load balance among the systems can be implemented only by a switching and redirecting method, and if the scheme of joint transmission is adopted, the network side can dynamically adjust the transmission rate of each user equipment on different links according to the load of different access systems, so that the load balance can be better realized.

When the user equipment adopts the scheme of joint transmission, the user equipment must have the capability of simultaneously supporting hardware and software of two access technologies, and under a joint transmission mode, the problem of how to transmit data through two systems and how to ensure complete and ordered data transmission needs to be solved.

Disclosure of Invention

In view of this, the main objective of the present invention is to provide a method for data transmission in joint transmission, a network element side and a user equipment, which solve the problem of data transmission when the user equipment accesses two systems simultaneously, help the network side to distribute data reasonably, and help to improve the data transmission rate of the user equipment.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

the invention provides a method for sending downlink data in joint transmission, which comprises the following steps:

the anchor point network element and the non-anchor point network element which participate in the joint transmission adopt a data transmission protocol architecture of a Media Access Control (MAC) layer to distribute data packets;

the MAC layer of the data transmission protocol architecture comprises an MAC-1 entity and an MAC-2 entity which are positioned at an anchor network element, and an MAC-2 entity which is positioned at a non-anchor network element;

when the data is transmitted jointly, the MAC-1 entity positioned in the anchor point network element distributes the downlink data packet to each MAC-2 entity, and the MAC-2 entity receiving the downlink data packet sends the received downlink data packet to the user equipment.

In the above solution, the data transmission protocol architecture for the MAC layer to distribute the data packet further includes: a Packet Data Convergence Protocol (PDCP) layer and a Radio Link Control (RLC) layer;

the anchor point network element enables the downlink Data packet to sequentially pass through a PDCP entity of a PDCP layer and an RLC entity of an RLC layer, and generates an RLC Protocol Data Unit (PDU); the RLC entity transmits the RLC PDU to the MAC-1 entity of the MAC layer.

In the above scheme, the MAC-1 entity located in the anchor network element distributes the downlink data packet to each MAC-2 entity, and the method includes: the MAC-1 entity distributes downlink data packets to each MAC-2 entity through a data interface according to a preset distribution strategy;

the preset distribution strategy is as follows: a strategy for distributing the downlink data packets according to a set proportion, or a strategy for determining the proportion for distributing the downlink data packets according to the quality of the wireless channel.

In the above scheme, the method further comprises:

the user equipment is internally provided with a protocol stack corresponding to a system where the anchor point network element is located and a protocol stack corresponding to a system where the non-anchor point network element is located, the user equipment is provided with an MAC-1 entity and an MAC-2 entity in the protocol stack corresponding to the system where the anchor point network element is located, the protocol stack corresponding to the system where the non-anchor point network element is located is provided with an MAC-2 entity, and a data interface is established between the MAC-1 entity and the MAC-2 entity.

In the above scheme, the method further comprises: the physical layer of the user equipment obtains a downlink data packet, and sends the obtained downlink data packet to an MAC-1 entity of a protocol stack corresponding to a system in which an anchor point network element is located in the user equipment through an MAC-2 entity of the protocol stack corresponding to the system in which an anchor point network element is located in the user equipment and/or an MAC-2 entity of the protocol stack corresponding to the system in which a non-anchor point network element is located;

and the MAC-1 entity of a protocol stack corresponding to a system in which the anchor point network element in the user equipment is positioned sends the downlink data packet to an application layer through an RLC entity and a PDCP entity of the user equipment in sequence.

In the above scheme, the method further comprises: when the user equipment sends the uplink data packet, the uplink data packet is distributed to each MAC-2 entity in the user equipment through the MAC-1 entity of the protocol stack corresponding to the system in which the anchor point network element is located, and the MAC-2 entity sends the uplink data packet to the anchor point network element and/or the non-anchor point network element through the physical layer.

In the above scheme, the method further comprises: the physical layer of the anchor network element and/or the non-anchor network element obtains an uplink data packet sent by the user equipment, and sends the uplink data packet to the MAC-1 entity located in the anchor network element through the MAC-2 entity located in the physical layer;

and the MAC-1 entity positioned at the anchor network element sends the uplink data packet to a PDCP entity through the RLC entities of the anchor network element in sequence.

In the above solution, the anchor point network element is an access network element of a system that has established Radio Resource Control (RRC) connection with a user equipment.

In the above solution, when the system that has established RRC connection with the user equipment is a UMTS system, the anchor point network element is an RNC or a base station of the UMTS system; or, when the system which has established the RRC connection with the user equipment is an LTE system, the anchor point network element is an evolved base station of the LTE system.

The invention provides a method for receiving downlink data in joint transmission, which comprises the following steps:

the user equipment sets an MAC-1 entity and an MAC-2 entity in a protocol stack corresponding to a system in which an anchor point network element is located in the user equipment, sets an MAC-2 entity in a protocol stack corresponding to a system in which a non-anchor point network element is located in the user equipment, and establishes a data interface between the MAC-1 entity and the MAC-2 entity;

a physical layer of user equipment acquires a downlink data packet, and sends the acquired downlink data packet to an MAC-1 entity of a protocol stack corresponding to a system in which an anchor point network element is located in the user equipment through an MAC-2 entity of the protocol stack corresponding to the system in which an anchor point network element is located in the user equipment and/or an MAC-2 entity of the protocol stack corresponding to the system in which a non-anchor point network element is located;

The invention provides a method for sending uplink data in joint transmission, which comprises the following steps:

when the user equipment sends the uplink data packet, the uplink data packet is distributed to each MAC-2 entity in the user equipment through the MAC-1 entity of the protocol stack corresponding to the system in which the anchor point network element is located, and the MAC-2 entity sends the uplink data packet to the anchor point network element and/or the non-anchor point network element through the physical layer.

The invention provides a method for receiving uplink data in joint transmission, which comprises the following steps:

the anchor point network element and the non-anchor point network element which participate in the joint transmission adopt a data transmission protocol architecture of a data packet distributed by an MAC layer;

the physical layer of the anchor network element and/or the non-anchor network element obtains an uplink data packet sent by user equipment, and sends the uplink data packet to an MAC-1 entity located in the anchor network element through an MAC-2 entity located in the physical layer;

The invention provides a network element side for data transmission in combined transmission, which comprises: an anchor network element and a non-anchor network element; wherein,

the anchor network element and the non-anchor network element adopt a data transmission protocol architecture of a data packet distributed by an MAC layer, and the MAC layer of the data transmission protocol architecture comprises an MAC-1 entity and an MAC-2 entity which are positioned on the anchor network element and an MAC-2 entity which is positioned on the non-anchor network element;

the anchor point network element is used for distributing downlink data packets to each MAC-2 entity through the MAC-1 entity positioned on the anchor point network element, and the MAC-2 entity sends the received downlink data packets distributed by the MAC-1 entity to the user equipment;

and the non-anchor network element is used for sending the received downlink data packet distributed by the MAC-1 entity to the user equipment through the MAC-2 entity of the non-anchor network element.

In the above scheme, the anchor point network element is specifically configured to send a downlink data packet to the MAC-1 entity through the PDCP entity and the RLC entity in sequence when jointly transmitting data; and distributing the received downlink data packet to each MAC-2 entity positioned at the anchor network element and each MAC-2 entity positioned at the non-anchor network element through the MAC-1 entity.

The invention provides a user equipment for data transmission in joint transmission, which comprises: a data packet receiving unit and a protocol layer transmission unit; wherein,

the data packet receiving unit is used for acquiring a downlink data packet at a physical layer;

a protocol layer transmission unit, configured to send the obtained downlink data packet to an MAC-1 entity of a protocol stack corresponding to a system in which the anchor point network element is located in the user equipment through an MAC-2 entity of the protocol stack corresponding to the system in which the anchor point network element is located in the user equipment and/or an MAC-2 entity of the protocol stack corresponding to the system in which the non-anchor point network element is located; and sending the downlink data packet to an application layer through an RLC entity and a PDCP entity of the user equipment in sequence by an MAC-1 entity of a protocol stack corresponding to a system where the anchor point network element in the user equipment is located.

The invention provides a user equipment for data transmission in joint transmission, which comprises: a packet transmitting unit; wherein,

the data packet sending unit is configured to distribute the uplink data packet to each MAC-2 entity in the user equipment through an MAC-1 entity of a protocol stack corresponding to a system in which an anchor point network element is located in the user equipment when sending the uplink data packet, where the MAC-2 entity sends the uplink data packet to the anchor point network element and/or the non-anchor point network element through a physical layer.

the anchor network element and the non-anchor network element adopt a data transmission protocol architecture of a data packet distributed by an MAC layer;

the anchor point network element is used for sending the uplink data packet sent by the user equipment to the MAC-1 entity through the MAC-2 entity of the anchor point network element when the uplink data packet is obtained by the physical layer; the MAC-1 entity sends the received uplink data packets to a PDCP entity through the RLC entities of the anchor network element in sequence;

and the non-anchor network element is used for sending the uplink data packet to the MAC-1 entity positioned on the anchor network element through the MAC-2 entity positioned on the non-anchor network element when the uplink data packet sent by the user equipment is obtained on the physical layer.

The invention provides a method for data transmission in joint transmission, a network element side and user equipment, wherein an anchor point network element and a non-anchor point network element which participate in the joint transmission adopt a data transmission protocol architecture of an MAC layer for distributing data packets; the MAC layer of the data transmission protocol architecture comprises an MAC-1 entity and an MAC-2 entity which are positioned at an anchor network element, and an MAC-2 entity which is positioned at a non-anchor network element; when the data is transmitted jointly, the MAC-1 entity positioned in the anchor point network element distributes the downlink data packet to each MAC-2 entity, and the MAC-2 entity receiving the downlink data packet sends the received downlink data packet to the user equipment; therefore, the data transmission problem in a combined transmission mode is solved, the reasonable data distribution at the network side is facilitated, and the data transmission rate of the user equipment is improved.

Drawings

Fig. 1 is a schematic diagram of an architecture of a conventional third generation partnership project access system;

fig. 2 is a schematic diagram of a structure in which a ue employs joint transmission in the prior art;

fig. 3 is a flowchart illustrating a method for sending downlink data in joint transmission according to the present invention;

fig. 4 is a flowchart illustrating a method for implementing downlink data transmission in joint transmission according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a data transmission protocol architecture of a data packet distributed by an MAC layer of an RNC according to an embodiment of the present invention;

fig. 6 is a flowchart illustrating a method for implementing downlink data transmission in joint transmission according to a second embodiment of the present invention;

fig. 7 is a schematic diagram of a data transmission protocol architecture of a data packet distributed by the MAC layer of the enb 3 according to the second embodiment of the present invention.

Detailed Description

The basic idea of the invention is: the anchor point network element and the non-anchor point network element which participate in the joint transmission adopt a data transmission protocol architecture of a data packet distributed by an MAC layer; the MAC layer of the data transmission protocol architecture comprises an MAC-1 entity and an MAC-2 entity which are positioned at an anchor network element, and an MAC-2 entity which is positioned at a non-anchor network element; when the data is transmitted jointly, the MAC-1 entity positioned in the anchor point network element distributes the downlink data packet to each MAC-2 entity, and the MAC-2 entity receiving the downlink data packet sends the received downlink data packet to the user equipment.

The invention is further described in detail below with reference to the figures and the specific embodiments.

The invention realizes a method for sending downlink data in joint transmission, as shown in fig. 3, the method comprises the following steps:

step 101: the anchor point network element and the non-anchor point network element which participate in the joint transmission adopt a data transmission protocol architecture of a Media Access Control (MAC) layer to distribute data packets;

in this step, the data transmission protocol architecture of the MAC layer for distributing the data packet includes: a PDCP layer, an RLC layer and an MAC layer; the MAC layer comprises a MAC-1 entity and a MAC-2 entity which are positioned on an anchor network element and a MAC-2 entity which is positioned on a non-anchor network element, and the MAC-1 entity and the MAC-2 entity communicate through a data interface;

specifically, when the combined transmission configuration is performed, the anchor point network element, the non-anchor point network element and the user equipment configure user plane parameters of a data transmission protocol architecture which adopts an MAC layer to distribute data packets;

the anchor network element, the non-anchor network element and the user equipment configure user plane parameters of a data transmission protocol architecture adopting an MAC layer to distribute data packets, and the method comprises the following steps: after determining to perform joint transmission, the anchor point network element configures user plane parameters of a data transmission protocol architecture which adopts an MAC layer to distribute data packets, wherein the user plane parameters include: a PDCP layer PDCP entity, a RLC layer RLC entity, data transmission parameters of an MAC-1 entity and an MAC-2 entity of an MAC layer, storage report parameters (BSR) and the like, and sends a joint transmission request to a non-anchor network element; after receiving the joint transmission request, the non-anchor network element sets an MAC-2 entity aiming at the user equipment; the user equipment acquires the joint transmission according to the bearing establishment or reconfiguration signaling sent by the anchor point network element, and then configures the user plane parameters of the data transmission protocol architecture which adopts the MAC layer to distribute the data packets.

The user equipment configures user plane parameters of a data transmission protocol architecture which distributes data packets by adopting an MAC layer, and the user plane parameters comprise: configuring data transmission parameters, storage report parameters and the like of a PDCP layer PDCP entity, an RLC layer RLC entity, an MAC-1 entity and an MAC-2 entity of user equipment, wherein the storage report parameters are optional; the user equipment is internally provided with a protocol stack corresponding to a system where the anchor point network element is located and a protocol stack corresponding to a system where the non-anchor point network element is located, the user equipment is provided with a self MAC-1 entity and a self MAC-2 entity in the protocol stack corresponding to the system where the anchor point network element is located, the protocol stack corresponding to the system where the non-anchor point network element is located is provided with a self MAC-2 entity, and a data interface is established between the self MAC-1 entity and the MAC-2 entity.

Step 102: when data are transmitted jointly, the MAC-1 entity positioned at the anchor point network element distributes a downlink data packet to each MAC-2 entity;

specifically, when data is transmitted jointly, a downlink data packet of an anchor point network element sequentially passes through a PDCP entity and an RLC entity to generate an RLC PDU, and the RLC entity sends the RLC PDU to an MAC-1 entity; and the RLC PDU is the MAC SDU after reaching the MAC-1 entity, and the MAC-1 entity distributes the received downlink data packet to each MAC-2 entity positioned at the anchor point network element and each MAC-2 entity positioned at the non-anchor point network element through a data interface. Here, after the downlink data packet sequentially passes through the PDCP entity and the RLC entity, functions such as ciphering, segmentation, etc. have been implemented, and for the ordered transmission of the downlink data packet, the PDCP entity and the RLC entity add respective Sequence Numbers (SNs) to the downlink data packet.

In this step, the MAC-1 entity distributes the received downlink data packet to each MAC-2 entity located in the anchor network element and each MAC-2 entity located in the non-anchor network element through the data interface, which generally includes: the MAC-1 entity distributes downlink data packets to each MAC-2 entity through a data interface according to a preset distribution strategy, such as: the system where the anchor network element and the non-anchor network element are respectively a UMTS system and an LTE system, the preset distribution strategy is to distribute downlink data packets according to a set proportion, and if the set proportion is 1 to 1, the MAC-1 entity sends 50% of downlink data packets to the MAC-2 entity of the UMTS system, and the other 50% of downlink data packets are sent to the MAC-2 entity of the LTE system; or, the preset distribution strategy is to determine the proportion of distributing the downlink data packets according to the quality of the wireless channel, and then the MAC-1 entity obtains the quality of the wireless channel of the system where the anchor network element and the non-anchor network element are located according to the measurement report of the user equipment, wherein the proportion of the better part of the wireless channel quality is large, and the proportion of the worse part of the wireless channel quality is small, for example, when the MAC-1 entity obtains the quality of the wireless channel of the system where the anchor network element is located according to the measurement report of the user equipment, and the quality of the wireless channel of the system where the non-anchor network element is located is not suitable for transmitting data, the MAC-1 entity does not distribute the downlink data packets to the MAC-2 entity located at the anchor network element, and distributes the downlink data packets to the; when the MAC-1 entity obtains that the quality of a wireless channel of a system where an anchor network element is located is better and the quality of the wireless channel of the system where a non-anchor network element is located is not suitable for transmitting data according to a measurement report of user equipment, the MAC-1 entity distributes a downlink data packet to an MAC-2 entity located in the anchor network element and does not distribute the downlink data packet to the MAC-2 entity located in the non-anchor network element; when the MAC-1 entity obtains the quality of a wireless channel of a system where an anchor network element is located and the quality of a wireless channel of a system where a non-anchor network element is located according to a measurement report of user equipment, wherein the quality of the wireless channel of the system where the non-anchor network element is located is both suitable for transmitting data, but the quality of the wireless channel of the system where the anchor network element is located is better than that of the system where the non-anchor network element is located, the proportion of downlink data packets distributed to the MAC-2 entity located in the anchor network element by the MAC-1 entity is greater than that of the downlink; and so on.

In this embodiment, the anchor point network element is an access network element of a system that has established an RRC connection with a user equipment; when the system which establishes RRC connection with the user equipment is a UMTS system, the anchor point network element is an RNC or a base station of the UMTS system; or, when the system that has established the RRC connection with the user equipment is an LTE system, the anchor point network element is an evolved base station of the LTE system, and the like.

In this step, when the ue is configured to transmit data by using a High Speed Packet Access (HSPA) technology, that is, an Uplink is a High Speed Uplink Packet Access (HSUPA), a Downlink is a High Speed Downlink Packet Access (HSDPA), and a spreading code used by the ue, a timeslot using the spreading code, and the like are controlled by the base station, the MAC-2 entity is disposed in the base station of the UMTS system in the UMTS system; in the UMTS system, the MAC-2 entity is located in the RNC of the UMTS system when the user equipment is not configured to transmit data using HSPA technology.

Step 103: the MAC-2 entity receiving the downlink data packet sends the received downlink data packet to the user equipment;

specifically, the MAC-2 entity that receives the downlink data packet multiplexes the received downlink data packet and sends the multiplexed downlink data packet to the physical layer of the user equipment; the MAC-2 entity receiving the downlink data packet may be a MAC-2 entity located at an anchor network element and/or a MAC-2 entity located at a non-anchor network element.

The embodiment further includes a method for receiving downlink data in joint transmission, where the method includes:

the physical layer of the user equipment sends the obtained downlink data packet to the MAC-1 entity of the protocol stack corresponding to the system in which the anchor point network element is located in the user equipment through the MAC-2 entity of the protocol stack corresponding to the system in which the anchor point network element is located in the user equipment and/or the MAC-2 entity of the protocol stack corresponding to the system in which the non-anchor point network element is located in the user equipment, wherein the MAC-2 entity of the protocol stack corresponding to the system in which the anchor point network element is located in the user equipment and/or the MAC-2 entity of the protocol stack corresponding to the system in which the non-anchor point network element is located in the user equipment also demultiplex (demultiplex) the; the MAC-1 entity of a protocol stack corresponding to a system where an anchor point network element in the user equipment is located sends the downlink data packet to an application layer after sequentially passing through an RLC entity and a PDCP entity of the user equipment;

the RLC entity sends the complete combination of the data packets to the PDCP entity of the RLC entity according to the SN of the RLC layer, and the PDCP entity sends the data packets to the application layer in sequence according to the SN of the PDCP layer, so that the user equipment can receive the complete and ordered data packets.

The embodiment further includes a method for sending uplink data in joint transmission, where the method includes:

when user equipment sends an uplink data packet, the uplink data packet is distributed to each MAC-2 entity in the user equipment through the MAC-1 entity of a protocol stack corresponding to a system in which an anchor point network element in the user equipment is located;

and the MAC-2 entity sends the uplink data packet to an anchor network element and/or a non-anchor network element through a physical layer.

The embodiment further includes a method for receiving uplink data in joint transmission, where the method includes:

In order to implement the above method, the present invention further provides a network element side for data transmission in joint transmission, where the network element side includes: an anchor network element and a non-anchor network element; wherein,

The anchor point network element is specifically used for sending a downlink data packet to an MAC-1 entity through a PDCP entity and an RLC entity in sequence when data are jointly transmitted; and distributing the received downlink data packet to each MAC-2 entity positioned at the anchor network element and each MAC-2 entity positioned at the non-anchor network element through the MAC-1 entity.

The anchor point network element is further used for distributing the downlink data packet to each MAC-2 entity through the MAC-1 entity and the data interface according to a preset distribution strategy.

Based on the above network element side, the present invention further provides a user equipment for data transmission in joint transmission, where the user equipment includes: a data packet receiving unit and a protocol layer transmission unit; wherein,

The present invention also provides a user equipment for data transmission in joint transmission, the user equipment comprising: a packet transmitting unit; wherein,

The data packet sending unit is specifically configured to distribute downlink data packets to each MAC-2 entity in the user equipment according to a preset distribution strategy through an MAC-1 entity and a data interface of a protocol stack corresponding to a system in which an anchor point network element in the user equipment is located; the preset distribution strategy comprises the following steps: a strategy for distributing downlink packets according to a set ratio, a strategy for determining the ratio for distributing downlink packets according to the quality of a radio channel, and the like.

Based on the user equipment, the present invention further provides a network element side for data transmission in joint transmission, where the network element side includes: an anchor network element and a non-anchor network element; wherein,

The following detailed description of the implementation and principles of the method of the present invention is provided in connection with specific embodiments.

Example one

In this embodiment, the UE1 resides in a cell 1 managed by a base station 1 in the UMTS system, and is in an idle state, and the base station 1 is managed by an RNC. A cell 2 having the same coverage (or overlapping coverage) as the cell 1 is governed by an evolved base station 2, and the evolved base station 2 belongs to the LTE system. In the UMTS system, an Iub interface is established between the RNC and the base station 1. Since the RNC may implement joint transmission with the enb 2 in LTE, a new interface is established between the RNC and the enb 2 for transferring data and control signaling. The interface establishment between the RNC and the enb 2 may be implemented by an Operation and Maintenance (Operation & Maintenance) server. In this embodiment, a method for downlink data transmission in joint transmission is implemented, as shown in fig. 4, the method includes the following steps:

step 201, UE1 initiates random access in cell 1, and sends RRC connection request to RNC;

step 202, the RNC receives the connection request sent by the UE1, and returns an RRC connection setup (RRC ConnectionSetup) Signaling to the UE1, where the RRC connection setup Signaling includes configuration parameters of a Signaling Radio Bearer (SRB);

step 203, the UE1 sends an RRC Connection Setup Complete (RRC Connection Setup Complete) signaling to the RNC by using the configuration parameters of the SRB in the RRC Connection Setup signaling;

the RRC connection setup complete signaling also includes capability information of the UE1, i.e., capability information that the UE1 supports joint transmission.

To this end, the UE1 has established an RRC connection with the RNC.

Step 204, the UE1 sends an Initial Direct Transfer (Initial Direct Transfer) signaling to the RNC, where the signaling includes a non-access stratum signaling, that is, a service request; after receiving the initial direct transmission signaling, the RNC sends a service request to a core network;

step 205, after receiving the service Request and successfully authenticating the user equipment, the core network returns a Radio Access Bearer Assignment Request (Radio Access Bearer Assignment Request) to the RNC, where the Radio Access Bearer Assignment Request includes quality of service parameters of a Data Radio Bearer (Data Radio Bearer) DRB1 to be established.

In this step, the DRB1 of the bearer corresponding to the empty port of the radio access bearer assignment request has a high data transmission rate required by the DRB1, i.e. the data rate included in the qos parameter is high.

Step 206, the RNC detects that the radio resource of the cell 1 cannot meet the data transmission rate requirement of the DRB1, the RNC selects the cell 2 as a target cell for joint transmission, the RNC configures the user plane parameters of the data transmission protocol architecture for distributing the data packets by its MAC layer, and sends a joint transmission request to the enb 2 through the interface between the RNC and the enb 2;

in this step, a data transmission protocol architecture of the data packet distributed by the MAC layer of the RNC is shown in fig. 5, and includes: a PDCP layer, an RLC layer and an MAC layer; wherein, the MAC layer comprises an MAC-1 entity and an MAC-2 entity which are positioned in the RNC, and an MAC-2 entity which is positioned in the evolution base station 2;

the RNC configures user plane parameters of a data transmission protocol architecture of a self MAC layer distribution data packet, and specifically comprises the following steps: the RNC configures data transmission parameters, storage report parameters and the like of a PDCP entity of a self PDCP layer, an RLC entity of an RLC layer, an MAC-1 entity of an MAC layer and an MAC-2 entity, wherein the storage report parameters are optional;

the joint transmission request comprises service quality parameter information of the DRB1 and cell identification information of the cell 2;

and the RNC obtains the decision that the cell 1 cannot meet the requirement of the DRB1 according to the used radio resources of the cell 1 and the radio resources occupied by the DRB 1.

Further, the RNC sends a measurement configuration to the UE1, and selects cell 2 as a target cell for joint transmission according to a measurement report returned by the UE 1.

The present embodiment does not limit the signaling name used for indicating that cross-system association transmission needs to be established, nor does the present embodiment limit the exact name of the MAC layer divided into two parts, and the present embodiment adopts the names of the MAC-1 entity and the MAC-2 entity, and in practice, other names may be adopted, such as the MAC-Share entity and the MAC-Schedule entity, where the MAC-1 entity or the MAC-Share entity has a function of distributing a data packet, the MAC-2 entity or the MAC-Schedule entity has a function of scheduling resources, and the MAC-2 entity or the MAC-Schedule entity schedules resources to send the data packet through the physical layer.

Step 207, after receiving the joint transmission request, the enb 2 receives the request, allocates the radio resource of the UE1 in the cell 2, returns the allocated radio resource to the RNC through the joint transmission response, and sets a MAC-2 entity for the UE1 in itself;

the radio resource returned to the RNC includes at least one of the following: RNTI, scrambling code, random access parameter, physical layer configuration parameter, etc. in the cell 2.

Step 208, after receiving the joint transmission response returned by the enb 2, the RNC allocates radio resources of the UE1 in the cell 1, and sends a bearer establishment signaling to the UE1 through an RRC signaling, where the bearer establishment signaling includes radio resources allocated by the RNC to the UE1 and radio resources allocated by the enb 2 to the UE 1;

the bearer establishment signaling may reuse an existing RRC signaling, such as radio bearer establishment, radio bearer reconfiguration, or RRC connection reconfiguration, or may newly add an RRC signaling, where the RRC signaling carries radio resources allocated to the user equipment in each joint transmission system.

Step 209, after receiving the bearer establishment signaling, UE1 obtains the radio resource configured by enodeb 2 for UE1 and the radio resource configured by RNC for UE1, and configures the user plane parameters of the data transmission protocol architecture for the MAC layer to distribute data packets;

in this step, the UE1 has a protocol stack corresponding to the UMTS system and a protocol stack corresponding to the LTE system inside, the UE1 sets its MAC-1 entity and MAC-2 entity in the protocol stack corresponding to the UMTS system, sets its MAC-2 entity in the protocol stack corresponding to the LTE system, and establishes a data interface between its MAC-1 entity and MAC-2 entity; the UE1 configures data transmission parameters, storage report parameters, etc. of its PDCP layer PDCP entity, RLC layer RLC entity, MAC-1 entity and MAC-2 entity, wherein the storage report parameters are optional.

It should be noted that, in step 209, the UE1 receives the radio resource of the cell 2, which may include a random access resource, the random access resource is allocated by the enodeb 2 and sent to the UE1 via the RNC, and the UE1 initiates a random access in the cell 2 according to the random access resource to obtain uplink synchronization.

Considering that when an operator lays out a network for joint transmission, in order to reduce synchronization problems of the UE in different systems, the UMTS system and the LTE system are deployed in a synchronization state, that is, the UE1 automatically acquires synchronization with the LTE system after acquiring synchronization with the UMTS, so that the UE1 does not need to perform random access in the cell 2 to acquire uplink synchronization, and at this time, the radio resource allocated by the cell 2 to the UE1 may not include a random access resource.

Step 210: when data are transmitted jointly, the MAC-1 entity positioned in the RNC distributes downlink data packets to the MAC-2 entities positioned in the RNC and the evolution base station 2;

specifically, when data is transmitted jointly, a downlink data packet of the RNC sequentially passes through the PDCP entity and the RLC entity to generate an RLC PDU, and the RLC entity sends the RLC PDU to the MAC-1 entity; the RLC PDU is the MAC SDU after reaching the MAC-1 entity, and the MAC-1 entity distributes the received downlink data packets to each MAC-2 entity positioned at the RNC and each MAC-2 entity positioned at the base station 2 through a data interface according to a preset distribution strategy. Here, after the downlink data packet sequentially passes through the PDCP entity and the RLC entity, functions such as ciphering, segmentation, etc. have been implemented, and in order to transmit the downlink data packet in order, the PDCP entity and the RLC entity add respective SNs to the downlink data packet.

Step 211: the MAC-2 entity that receives the downlink data packet sends the received downlink data packet to the UE 1;

specifically, when receiving downlink data packets, the MAC-2 entities in the RNC and the enb 2 respectively multiplex the received downlink data packets and send the multiplexed downlink data packets to the physical layer of the UE 1.

Step 212: the UE1 combines the obtained data packets to obtain complete data.

Specifically, the physical layer of the UE1 sends the obtained downlink data packet to the MAC-1 entity of the protocol stack corresponding to the UMTS system in the UE1 through the MAC-2 entity of the protocol stack corresponding to the UMTS system in the UE and/or the MAC-2 entity of the protocol stack corresponding to the LTE system, where the MAC-2 entity of the protocol stack corresponding to the UMTS system in the UE and/or the MAC-2 entity of the protocol stack corresponding to the LTE system also demultiplex the downlink data packet; the MAC-1 entity of a protocol stack corresponding to a UMTS system in the UE1 sends the downlink data packet to an application layer through an RLC entity and a PDCP entity of the UE1 in sequence;

the RLC entity sends the complete combination of the data packets to its PDCP entity according to the SN of the RLC layer, and the PDCP entity sends the data packets to the application layer in sequence according to the SN of the PDCP layer, so that the UE1 can receive the complete and ordered data packets.

In this embodiment, the RNC is an anchor network element, and the enb 2 of the LTE system is a non-anchor network element.

Example two

In this embodiment, the UE2 is in a connected state through the LTE system access network, and the UE2 accesses the cell 3 governed by the enodeb 3, that is, the enodeb 3 has already established an RRC connection for the UE 2. The base station 4 in the UMTS system is administered by RNC, and the coverage area of the cell 4 and the cell 3 which are administered by the base station 4 are overlapped.

The application scenario of this embodiment is as follows: the UE2 has established a Data Radio Bearer (DRB), denoted DRB1 below. If the UE2 needs to create a new DRB2 for data radio bearer and the enodeb 3 does not have enough resources to meet the qos parameter requirement of the new DRB2 of the UE2, since the enodeb 3 already knows that the UE2 has the capability of supporting joint transmission when the UE2 accesses the network, the enodeb 3 wants to use the joint transmission method so that the UE2 can obtain more radio resources. The enb 3 learns that the signal quality of the cell 4 measured by the UE2 exceeds a predetermined threshold through a measurement report reported by the UE2, and the enb 3 configures joint transmission for the UE 2. As shown in fig. 6, the method for downlink data transmission in joint transmission in this embodiment includes the following steps:

step 301, the evolution base station 3 configures the user plane parameters of the data transmission protocol architecture of the data packet distributed by the MAC layer of itself, and sends a joint transmission request to the RNC through the interface between itself and the RNC;

in this step, a data transmission protocol architecture of the MAC layer of the enb 3 for distributing the data packet is shown in fig. 7, and includes: a PDCP layer, an RLC layer and an MAC layer; wherein, the MAC layer comprises an MAC-1 entity and an MAC-2 entity which are positioned at an evolution base station 3, and an MAC-2 entity which is positioned at an RNC;

the evolved node b 3 configures user plane parameters of a data transmission protocol architecture of a data packet distributed by a self MAC layer, specifically: the evolution base station 3 configures data transmission parameters, storage report parameters and the like of a PDCP entity, an RLC entity, an MAC-1 entity and an MAC-2 entity of a PDCP layer of the evolution base station 3;

the joint transmission request includes the service quality parameter information of the DRB2 and the cell identification information of the cell 4.

Step 302, after receiving the joint transmission request, the RNC receives the request, allocates the radio resource of the UE2 in the cell 4, returns the allocated radio resource to the enb 3 through the joint transmission response, and sets the MAC-2 entity for the UE2, and configures the data transmission parameter, the storage report parameter, and the like of the MAC-2 entity;

the radio resources returned and allocated to the evolved node B3 include RNTI, scrambling codes, random access parameters, physical layer configuration parameters and the like in the cell 4 or RNC;

in this step, the radio resource of the UE2 in the cell 4 is generally allocated according to the quality of service parameter of the DRB2, so as to meet the data transmission requirement of the DRB2 of the user equipment as much as possible.

Step 303, after receiving the joint transmission response returned by the RNC, the enodeb 3 allocates the radio resource of the UE2 in the cell 3, and sends a bearer establishment signaling to the UE2 through the RRC signaling, where the bearer establishment signaling includes the radio resource configured by the enodeb 3 for the UE2 and the radio resource configured by the RNC for the UE 2;

in this step, the radio resources in the cell 4 include at least one of the following: RNTI, scrambling code, random access parameter, or physical layer configuration parameter in the cell 4.

Step 304, after receiving the bearer establishment signaling, the UE2 obtains the radio resource configured by the enodeb 3 for the UE2 and the radio resource configured by the RNC for the UE2, and configures the user plane parameters of the data transmission protocol architecture of the MAC layer distribution packet;

the user plane parameters in this step include: a PDCP layer PDCP entity, an RLC layer RLC entity, a MAC layer MAC-1 entity, and a MAC-2 entity of the UE2, a storage report parameter, and the like.

Step 305: when data is transmitted jointly, the MAC-1 entity positioned in the evolution base station 3 distributes downlink data packets to the MAC-2 entities positioned in the RNC and the evolution base station 3;

specifically, when data is transmitted jointly, a downlink data packet of the evolution base station 3 sequentially passes through the PDCP entity and the RLC entity to generate an RLC PDU, and the RLC entity sends the RLC PDU to the MAC-1 entity; the RLC PDU is the MAC SDU after reaching the MAC-1 entity, and the MAC-1 entity distributes the received downlink data packets to the MAC-2 entities positioned in the RNC and the MAC-2 entities positioned in the base station 3 according to a preset distribution strategy through a data interface. Here, after the downlink data packet sequentially passes through the PDCP entity and the RLC entity, functions such as ciphering, segmentation, etc. have been implemented, and in order to transmit the downlink data packet in order, the PDCP entity and the RLC entity add respective SNs to the downlink data packet.

Step 306: the MAC-2 entity that receives the downlink data packet sends the received downlink data packet to the UE 2;

specifically, when receiving downlink data packets, the MAC-2 entities in the RNC and the enb 3 respectively multiplex the received downlink data packets and send the multiplexed downlink data packets to the physical layer of the UE 2.

Step 307: and the UE2 combines the obtained downlink data packets to obtain complete data.

Specifically, the physical layer of the UE2 sends the obtained downlink data packet to the MAC-1 entity of the protocol stack corresponding to the LTE system in the UE2 through the MAC-2 entity of the protocol stack corresponding to the UMTS system in the UE and/or the MAC-2 entity of the protocol stack corresponding to the LTE system in the UE, where the MAC-2 entity of the protocol stack corresponding to the UMTS system in the UE and/or the MAC-2 entity of the protocol stack corresponding to the LTE system also demultiplex the downlink data packet; the MAC-1 entity of a protocol stack corresponding to an LTE system in the UE2 sends the downlink data packet to an application layer through an RLC entity and a PDCP entity of the UE2 in sequence;

the RLC entity sends the complete combination of the data packets to its PDCP entity according to the SN of the RLC layer, and the PDCP entity sends the data packets to the application layer in sequence according to the SN of the PDCP layer, so that the UE2 can receive the complete and ordered downlink data packets.

In this embodiment, the enodeb 3 is an anchor network element, and the RNC is a non-anchor network element.

In this embodiment, if the UE2 uses the HSPA technology on the UMTS side, the MAC-2 entity may be located in the base station 4, the base station 3 may transmit a downlink data packet of a user through an interface with the RNC, and then the RNC transmits the downlink data packet to the base station 4 through an interface with the base station 4, and the MAC-2 entity in the base station 4 is responsible for resource scheduling and transmits the downlink data packet to the UE 2; or a direct interface is established between the base station 3 and the base station 4, the base station 3 transmits a downlink data packet of a user to the base station 4 through the interface, and an MAC-2 entity in the base station 4 is responsible for resource scheduling and sends the downlink data packet to the UE 2.

In this embodiment, the MAC-1 entity distributes the received downlink data packet to each MAC-2 entity located in the RNC and each MAC-2 entity located in the base station 3 according to a preset distribution policy through the data interface, which is generally: the MAC-1 entity distributes the data packets according to a set proportion, or the MAC-1 entity determines the proportion of distributing the downlink data packets according to the quality of the wireless channel, such as: the MAC-1 entity dynamically adjusts the distribution proportion of the downlink data packets according to the wireless channel quality of the cell 3 and the cell 4 measured by the UE2, and if the wireless channel quality of the cell 3 is the same as that of the cell 4, the downlink data packets can be distributed according to the proportion of 1: 1; if the quality of the radio channel of the cell 3 is better, more downlink data packets can be allocated to the MAC-2 entity located in the base station 3, and higher throughput can be obtained by transmitting data through the link with good quality of the radio channel.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.

Claims

1. A method for sending downlink data in joint transmission is characterized in that the method comprises the following steps:

2. The method of claim 1, wherein the data transmission protocol architecture for the MAC layer to distribute the data packets further comprises: a Packet Data Convergence Protocol (PDCP) layer and a Radio Link Control (RLC) layer;

the anchor point network element enables the downlink data packet to sequentially pass through a PDCP entity of a PDCP layer and an RLC entity of an RLC layer, and an RLC Protocol Data Unit (PDU) is generated; the RLC entity transmits the RLC PDU to the MAC-1 entity of the MAC layer.

3. The method of claim 1, wherein the MAC-1 entity located in the anchor network element distributes the downlink data packet to each MAC-2 entity, and the method is as follows: the MAC-1 entity distributes downlink data packets to each MAC-2 entity through a data interface according to a preset distribution strategy;

4. The method of claim 1, further comprising:

5. The method of claim 4, further comprising: the physical layer of the user equipment obtains a downlink data packet, and sends the obtained downlink data packet to an MAC-1 entity of a protocol stack corresponding to a system in which an anchor point network element is located in the user equipment through an MAC-2 entity of the protocol stack corresponding to the system in which an anchor point network element is located in the user equipment and/or an MAC-2 entity of the protocol stack corresponding to the system in which a non-anchor point network element is located;

6. The method of claim 4, further comprising: when the user equipment sends the uplink data packet, the uplink data packet is distributed to each MAC-2 entity in the user equipment through the MAC-1 entity of the protocol stack corresponding to the system in which the anchor point network element is located, and the MAC-2 entity sends the uplink data packet to the anchor point network element and/or the non-anchor point network element through the physical layer.

7. The method of claim 6, further comprising: the physical layer of the anchor network element and/or the non-anchor network element obtains an uplink data packet sent by the user equipment, and sends the uplink data packet to the MAC-1 entity located in the anchor network element through the MAC-2 entity located in the physical layer;

8. The method of any of claims 1 to 7, wherein the anchor network element is an access network element of a system that has established a Radio Resource Control (RRC) connection with a user equipment.

9. The method of claim 8, wherein when the system that has established the RRC connection with the ue is a Universal Mobile Telecommunications System (UMTS) system, the anchor network element is an RNC or a base station of the UMTS system; or, when the system that has established the RRC connection with the user equipment is a Long Term Evolution (LTE) system, the anchor point network element is an evolved base station of the LTE system.

10. A method for receiving downlink data in joint transmission, the method comprising:

11. A method for transmitting uplink data in joint transmission, the method comprising:

12. A method for receiving uplink data in joint transmission, the method comprising:

13. A network element side for data transmission in joint transmission, the network element side comprising: an anchor network element and a non-anchor network element; wherein,

14. The network element side of claim 13, wherein the anchor point network element is specifically configured to send a downlink data packet to the MAC-1 entity via the PDCP entity and the RLC entity in sequence when jointly transmitting data; and distributing the received downlink data packet to each MAC-2 entity positioned at the anchor network element and each MAC-2 entity positioned at the non-anchor network element through the MAC-1 entity.

15. A user equipment for data transmission in a joint transmission, the user equipment comprising: a data packet receiving unit and a protocol layer transmission unit; wherein,

16. A user equipment for data transmission in a joint transmission, the user equipment comprising: a packet transmitting unit; wherein,

17. A network element side for data transmission in joint transmission, the network element side comprising: an anchor network element and a non-anchor network element; wherein,