WO2011038660A1 - Method and system for transmitting multimedia broadcast multicast service notification information - Google Patents

Abstract

The present invention provides a method and a system for transmitting Multimedia Broadcast Multicast Service (MBMS) notification information. When the number of MBMS Point to-multi -point Control Channels (MCCHs) used in the current cell is updated, the system side notifies a User Equipment (UE) of the updated number of the MCCHs used in the cell through the system message, searches the preset corresponding relationship between the number of MCCHs and the Downlink Control Information (DCI) format for the DCI format corresponding to the updated number of MCCHs used in the cell, adopts the found DCI format to bear the MBMS notification information, and sends the MBMS notification information to the UE; the UE receives the system message, acquires the updated number of MCCHs used in the cell from the message, searches the preset corresponding relationship between the number of MCCHs and the DCI format for the DCI format corresponding to the acquired updated number of MCCHs used in the cell, and adopts the found DCI format to detect and to receive the MBMS notification information.

Description

 Method and system for transmitting MBMS notification information

 The present invention relates to an LTE (Long Term Evolution) system, and in particular to a method and system for transmitting Multimedia Broadcast Multicast Service (MBMS) MBMS Notification information.

Background technique

 With the rapid development of the Internet and the popularity of large-screen multi-function mobile phones, a large number of mobile data multimedia services and various high-bandwidth multimedia services have emerged, such as video conferencing, television broadcasting, video on demand, advertising, online education, interactive games, and the like. This aspect meets the rising business needs of mobile users and brings new business growth points to mobile operators. These mobile data multimedia services require multiple users to receive the same data at the same time, and have the characteristics of large data volume, long duration, and delay sensitivity compared with general data services.

 In order to effectively utilize mobile network resources, 3rd Generation Partnership Project (3rd Generation)

The Partnership Project (3GPP) proposes the MBMS service, which is a technology for transmitting data from one data source to multiple targets, realizing the sharing of resources (including core network and access network) and improving network resources (especially Is the utilization of air interface resources). The MBMS defined by 3GPP can not only realize low-rate plain text message class multicast and broadcast, but also realize high-speed multimedia service broadcast and multicast, and provide a variety of rich video and audio multimedia services, which undoubtedly conforms to the future development of mobile data. The trend has provided a better business prospect for the development of 3G.

The MBMS service is characterized by a large amount of data in the service, a long duration of reception by the terminal, and a constant average data rate. The above characteristics determine that the scheduling and control signaling configuration of the MBMS service are semi-static, that is, the scheduling information and signaling information of the MBMS service are all "long-term" unchanged, so that each MCCH (MBMS Point to-multi- Point Control Channel, MBMS point-to-multipoint control channel), the system side sends a message without change (always sent because new users may be accessed at any time). Therefore, for a terminal that has received the MCCH information, it is not necessary to receive an MCCH information that has not changed every time, which will cause the terminal to charge power, because the MCCH information is large, and the receiving and parsing process consumes power. So proposed to add a MCCH letter Information update indication information (ie, MCCH change notification, or MBMS notification indicator, which may be referred to as an MBMS notification message, an MBMS notification message, or an MBMS notification indication, etc.), with a small amount of physical layer information to describe whether the MCCH information has changed, has been accessed. The terminal only needs to monitor a small amount of information, and according to the MBMS notification message terminal, it decides whether to receive the MCCH information, thereby saving power.

 In addition, the MBMS service transmission area may overlap. The eMBMS (Evolved MBMS) system may have multiple MCCHs. Each MCCH corresponds to a different MBMS service transmission area, and only the MBMS service sent by the corresponding MBMS service transmission area is carried. Control information. The number of MCCHs depends on the MBMS service occurrence area to which the service in the cell belongs, so the number of MCCHs is variable.

 As can be seen from the above, in LTE, there is an urgent need to propose a new MBMS notification message mechanism to apply multiple MCCHs and scenarios in which the number of MCCHs changes.

Summary of the invention

 The technical problem to be solved by the present invention is to provide a method and system for transmitting MBMS notification information, thereby transmitting MBMS notification information in the case where a plurality of MCCHs and MCCH numbers are changed.

 In order to solve the above technical problem, the present invention provides a method for transmitting MBMS notification information, including:

 When the number of MCCHs used in the current cell is updated, the system side notifies the user equipment of the number of MCCHs used in the updated cell by using the system message, and sets the number of MCCHs and the downlink control information (DCI) format that are set in advance. In the corresponding relationship, the DCI format corresponding to the number of MCCHs used in the updated cell is searched, and the MBMS notification information is carried by the found DCI format, and the MBMS notification information is sent to the user equipment.

The method further includes: the user equipment receives the system message, obtains the number of MCCHs used in the updated cell, and searches for the MCCH used in the acquired cell from the corresponding relationship between the number of MCCHs and the DCI format. The DCI format corresponding to the number of bars detects and receives the MBMS notification information using the DCI format found. In the above method, in the correspondence between the number of MCCHs and the DCI format, the number of MCCHs is proportional to the number of bits occupied by the corresponding DCI format.

 In the above method, the correspondence between the number of MCCHs and the DCI format includes a new DCI format. In the above method, when the number of MCCHs is different from the DCI format, the corresponding DCI formats are the same or different.

The invention also discloses a system for transmitting MBMS notification information, comprising a network side device and a user device, wherein:

 The network side device is configured to send a system message to the user equipment when the number of MCCHs used in the current cell is updated, where the system message includes the number of MCCHs used in the updated cell, and the number of MCCHs that are set in advance. In the DCI format, the DCI format corresponding to the number of MCCHs used in the updated cell is searched, and the MBMS notification information is carried by the found DCI format, and the MBMS notification information is sent to the user equipment;

 The user equipment is configured to receive the system message, obtain the number of MCCHs used in the updated cell, and search for the number of MCCHs used in the acquired cell from the corresponding relationship between the number of MCCHs and the DCI format. The DCI format detects and receives MBMS notification information using the DCI format found.

 In the above system, in the correspondence between the number of MCCHs and the DCI format, the number of MCCHs is proportional to the number of bits occupied by the corresponding DCI format.

 In the above system, the correspondence between the number of MCCHs and the DCI format includes a new DCI format. In the above system, when the number of MCCHs is different from the DCI format, the corresponding DCI formats are the same or different.

The present invention has different data requirements for transmitting MBMS notification information according to different numbers of MCCH channels, and flexibly selects existing downlink control information (DCI) format to carry MBMS notification information; and does not increase the premise of UE processing. In the following, it is avoided that a PDCCH DCI format capable of carrying more data is used to waste resources when the number of MCCHs is small. BRIEF abstract

 Figure 1 is a flow chart of the method of the present invention;

 2 is a schematic diagram of a network in the first embodiment;

 Fig. 3 is a flow chart of the first embodiment.

Preferred embodiment of the invention

 The main idea of the present invention is that the PDCCH (Physical Downlink Control Channel) generally transmits three types of information, namely: scheduling information of downlink data transmission, scheduling information of uplink data transmission, and uplink power control. The command, correspondingly, DCI (Downlink Control Information) format (format) can be divided into the following (where the number of bits is changed according to the bandwidth):

 DCI format 0, used to send resource allocation information of the uplink SCH (Shared Channel) (approximately 38 bits, 20 MHz bandwidth, 4 transmit antennas, including 16-bit CRC);

 DCI format 1 is used to send resource allocation information (about 56 bits) in the case of single-antenna port/transmit diversity (single rank open-loop scheme);

 DCI format 2, used to transmit resource allocation information (about 72 bits) in the case of downlink MIMO (open loop/closed loop multiplexing);

 DCI format 3 is used to transmit a 2-bit power control command (about 38 bits) for PUSCH (Physical Uplink Share Channel) and PUCCH (Physical Uplink Control Channel).

 In addition, for each format of DCI, there are different options, such as formatl, which can also be subdivided into 1A, 1B, 1C or ID for different occasions, and the number of bits it can carry is also different. .

Therefore, the technical solution of the present invention forms a mapping relationship between the MBMS notification information and the PDCCH DCI format. When the number of MCCH channels changes, it means that the number of bits of the MBMS notification information changes, and the PDCCH DCI format can be used to carry. The MBMS notification information, so that the UE can know the number of MCCHs in the current cell according to the system message, and correspondingly The mapping relationship can be used to know which PDCCH DCI format the MBMS notification information in the current cell is in, and use the corresponding DCI format to detect and receive the MBMS notification message, as shown in FIG.

 The system side (for example, the eNB or the BMSC broadcasts the multicast service center, etc.) and the UE side may

The corresponding relationship between the number of MCCHs and the DCI format is notified to the UE by the signaling. For example, the correspondence between the number of MCCHs and the DCI format can be as shown in Table 1:

 Table 1 shows the correspondence between the number of MCCHs and the DCI format.

 In different embodiments, the specific correspondence between the number of MCCHs and the DCI format may be based on the data load of the MBMS notification message under different MCCH numbers to select a corresponding DCI format (ie, the more the number of MCCHs, the data load of the MBMA notification message is also The larger, choose the DCI format with large resources);

In addition, it is also allowed to use the same DCI format to carry MBMS notification messages under different MCCH numbers. In some cases, there may be some resources waste.

The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings and specific embodiments.

A system for transmitting MBMS notification information, including a network side device and a UE. When the number of MCCHs used in the current cell is updated, the network side device sends a system message to the UE, where the system message includes the number of MCCHs used in the updated cell, and the number of MCCHs and the DCI format set in advance. In the corresponding relationship, the DCI format corresponding to the number of MCCHs used in the updated cell is searched, and the MBMS notification information is carried by the found DCI format, and the MBMS notification information is sent to the UE;

 The UE is configured to receive the system message, obtain the number of MCCHs used in the updated cell, and search for the corresponding number of MCCHs used in the acquired cell from the correspondence between the number of MCCHs and the DCI format that are set in advance. The DCI format detects and receives MBMS notification information by using the found DCI format;

 The corresponding relationship between the number of MCCHs and the DCI format may include a new DCI format, that is, when the existing DCI format is insufficient, a new DCI format (ie, a new DCI format) may be designed to match a certain number of MCCHs. MBMS notification message; different MCCH numbers can correspond to the same or different DCI formats.

 In a preferred embodiment, the larger the number of MCCHs, the greater the data load of the MBMA notification message. Therefore, the corresponding DCI is the larger the number of MCCHs and the DCI format. The more bits the format occupies.

Example 1

 In this embodiment, two MCCHs are configured in a cell as an example (as shown in FIG. 2), and the process of transmitting MBMS notification information is illustrated. The process is as shown in FIG. 3, and includes the following steps:

 Step 301: The system side sends the configuration information of the two MCCH channels to the UE in the system message, and selects one DCI format corresponding to the two MCCHs to carry the MBMS notification according to the corresponding relationship between the number of MCCHs and the DCI format. Information

 In this step, the correspondence between the number of MCCHs and the DCI format is agreed by the system side and the UE side in advance. If the existing DCI format is insufficient, a new DCI format (ie, a new DCI format) can be designed to match an MCCH. MBMS notification message under the number of bars;

In a preferred embodiment, the MBMA notification message data is considered when the number of MCCHs is increased. The load is also larger. Therefore, in the correspondence between the number of MCCHs and the DCI format set in advance, the number of bits occupied by the MCCH corresponding to the DCI format is larger.

 Step 302: The UE receives the foregoing system message, and learns from the system message that two MCCHs are configured in the current cell, and according to the corresponding relationship between the number of MCCHs and the DCI format, the MBMS notification information in the current cell is used. a DCI format to carry;

 Step 303: The UE detects and receives the MBMS notification information according to the found DCI format.

 Step 304: During the running of the system, if the MCCH is added to the cell, the system side updates the system message, and according to the added number of MCCHs, the number of MCCHs and the DCI format are set. Corresponding DCI format is selected in the corresponding relationship, and the MBMS notification information is carried by the DCI format and sent to the UE;

 Step 305: The UE receives the updated system message, and according to the content of the updated system message, the number of MCCHs used in the current cell is 3, and the new one is learned according to the corresponding relationship between the number of MCCHs and the DCI format. The MBMS notification information will be carried by which DCI format to use;

 Step 306: The UE detects and receives the MBMS notification information according to the new DCI format.

The above is only the embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the present invention. Within the scope of the appended claims.

Industrial applicability

 The present invention has different data requirements for transmitting MBMS notification information according to different numbers of MCCH channels, and flexibly selects an existing PDCCH DCI format to carry MBMS notification information; and avoids fixed configuration of one capable bearer without increasing UE processing. The PDCCH DCI format with more data is wasted when the number of MCCHs is small.

Claims

Claim  A method for transmitting MBMS notification information of a multimedia broadcast and a multicast service, comprising: when an MBMS point-to-multipoint control channel MCCH number used in a current cell is updated, the system side uses the system message to update the used cell. The number of MCCHs is notified to the user equipment, and the DCI format corresponding to the number of MCCHs used in the updated cell is searched for from the correspondence between the number of MCCHs and the downlink control information DCI format set in advance. The found DCI format carries MBMS notification information, and the MBMS notification information is sent to the user equipment.  2. The method of claim 1 further comprising:  Receiving, by the user equipment, the system message, obtaining the number of MCCHs used in the updated cell, and searching and obtaining the obtained information from the correspondence between the preset number of MCCHs and the DCI format. The DCI format corresponding to the number of MCCHs used in the updated cell, and detecting and receiving the MBMS notification information by using the found DCI format.  3. The method according to claim 1 or 2, wherein  In the correspondence between the number of MCCHs and the DCI format, the number of MCCHs is proportional to the number of bits occupied by the DCI format corresponding to the number of MCCHs.  4. The method according to claim 1 or 2, wherein  The corresponding relationship between the number of MCCHs and the DCI format includes a new DCI format.  5. The method according to claim 1 or 2, wherein  In the correspondence between the number of MCCHs and the DCI format, when the number of MCCHs is different, the corresponding DCI formats are the same or different.  6. A system for transmitting MBMS notification information for multimedia broadcast and multicast services, including network side devices and user equipment, wherein: The network side device is configured to send a system message to the user equipment when the number of the MBMS point-to-multipoint control channel MCCHs used in the current cell is updated, where the system message includes the MCCH strip used in the updated cell. And a DCI format corresponding to the number of MCCHs used in the updated cell in the correspondence between the number of MCCHs and the downlink control information DCI format, and the MBI in the found DCI format is used to carry the MBMS. Notice information Sending the MBMS notification information to the user equipment;  The user equipment is configured to receive the system message, obtain the number of MCCHs used in the updated cell, and search and obtain the obtained relationship between the MCCH number and the DCI format. The DCI format corresponding to the number of MCCHs used in the cell detects and receives the MBMS notification information by using the found DCI format.  7. The system of claim 6 wherein  In the correspondence between the number of MCCHs and the DCI format, the number of MCCHs is proportional to the number of bits occupied by the DCI format corresponding to the number of MCCHs.  8. The system of claim 6 wherein  The corresponding relationship between the number of MCCHs and the DCI format includes a new DCI format.  9. The system of claim 6 wherein  In the correspondence between the number of MCCHs and the DCI format, when the number of MCCHs is different, the corresponding DCI formats are the same or different.