WO2013120318A1

WO2013120318A1 - Method and system for achieving uplink subframe scheduling during subframe bundling

Info

Publication number: WO2013120318A1
Application number: PCT/CN2012/074008
Authority: WO
Inventors: 熊科
Original assignee: 中兴通讯股份有限公司
Priority date: 2012-02-17
Filing date: 2012-04-13
Publication date: 2013-08-22
Also published as: CN102595609A; CN102595609B

Abstract

Disclosed are a method and system for achieving uplink subframe scheduling during subframe bundling. The method comprises: when an uplink subframe bundling function for a terminal is enabled, according to the proportioning relationship between an uplink time slot and a downlink time slot, performing uplink time slot scheduling once on the terminal every fixed number of subframes. Aiming at an uplink subframe bundling application, the technology for achieving uplink subframe scheduling during subframe bundling of the present invention effectively reduces the overhead required when performing uplink scheduling on the terminal by scheduling the uplink subframe in a fixed cycle. In addition, the scheduling cycle can be dynamically configured in the background, thereby increasing the flexibility for performing a subframe bundling function.

Description

Method and system for implementing uplink subframe scheduling when subframes are bundled

The present invention relates to the field of communications, and in particular, to a method and system for implementing uplink subframe scheduling when a subframe is bundled. Background technique

The current universal terrestrial wireless communication network uses a honeycomb structure. Only one base station is deployed in a single cell. This is a typical star network where the channel quality of users at the edge of a star network can be degraded by various disturbances. In the LTE (Long Term Evolution) system, the probability of retransmission of the uplink HARQ (Hybrid Automatic Repeat Request) is greatly increased, and the communication delay is increased. The uplink subframe bundling technique is to transmit the same data in four consecutive uplink TTIs (Transmission Time Intervals) in the same HARQ process. This method can be applied to scenarios where the terminal is at the edge of the cell or other scenarios where the transmission delay is relatively high.

At present, the transmission timing corresponding to the first TTI in the subframe bundle has the authorization signaling to be sent on the PDCCH (hysical downlink control channel), and only the fourth bundle of the subframe is bundled ( That is, the last one) ACK/NACK (Acknowledgment/Negative-Acknowledgment, acknowledgment/rejection) is fed back through the PHICH (Physical Hybrid ARQ Indicator Channel).

LTE is divided into TDD (Time Division Duplex) mode and FDD (Frequency Division Duplex) mode. To implement uplink subframe bonding in TDD and FDD modes, the following requirements must be met:

When the terminal is configured as a subframe bundle, the RTT (Round-Trip Time) of the HARQ is increased by 2 times.

When the terminal is configured as a subframe bundle, the number of HARQ processes supported by the terminal is reduced to the original. Half.

According to the agreement, the number of HARQ processes of FDD is fixed to four, and the number of HARQ processes of TDD varies according to different time slot ratios, as shown in Table 1:

Table 1

The LTE protocol clearly states that TDD can only perform uplink subframe bundling when the uplink and downlink time slot ratios are 0, 1, and 6. When the TDD uplink and downlink time slot ratio is 0, the number of HARQ processes running in parallel on the terminal side is up to seven. When the terminal is configured as a subframe bundle, the number of HARQ processes running in parallel on the terminal side needs to be reduced to three. Therefore, it is necessary to calculate the transmission time of the PUSCH (Physical Uplink Shared Channel) packet according to the following rules:

When the high bit of the UL (uplink) Index field in the DCI (downlink control information) 0 received by the terminal in the nth subframe is set to 1, or IPHICH=0, the terminal needs to Transmitting a data packet of the first PUSCH at the n+kth subframe; when the lower bit of the UL Index field in the DCI0 received by the terminal in the nth subframe is set to 1, or I _PfflCH = 1, the terminal The data packet of the first PUSCH needs to be transmitted at subframe n+7. When the lower and upper bits of the UL Index field in the DCI0 received by the terminal in the nth subframe are simultaneously set, the terminal cannot transmit the PUSCH data packet at the n+k and n+7th subframes.

In view of this, for configuration 0, the judgment of subframe bundling for each TTI needs to be performed. For example, look at the UL Index first, then look at I _PfflCH . This implementation is more complicated and therefore more expensive. Summary of the invention

A main object of the present invention is to provide a method and system for implementing uplink subframe scheduling when subframes are bundled, so as to reduce the overhead required for calculating uplink subframe scheduling timing when subframes are bundled.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

A method for implementing uplink subframe scheduling when a subframe is bundled includes:

When the uplink subframe bundling function is enabled for the terminal, the uplink time slot scheduling is performed for the terminal according to the uplink/downlink slot ratio relationship.

The method further includes: confirming, by the medium access control MAC layer, an uplink subframe bundling function for the terminal.

The process of the MAC layer initiating the confirmation includes:

The MAC layer determines whether the uplink subframe bundling function of the terminal can be enabled according to the uplink channel quality of the terminal, and notifies the radio resource control RRC layer of the judgment result; the RRC layer finally determines whether the uplink subframe bundling function is enabled, and will eventually The decision result informs the MAC layer.

The RRC layer also notifies the terminal of the final decision result: The RRC layer sends an RRC reconfiguration message to notify the terminal whether the uplink subframe bundling function is enabled.

The method for performing the scheduling according to the uplink-downlink slot ratio relationship is:

The sub-frame bundling special scheduling mode is entered, and the control scheduler performs an uplink time slot scheduling for the terminal according to the algorithm parameters configured in the background, and the current communication mode and the uplink-downlink slot ratio relationship, and the fixed number of subframes per interval.

A system for implementing uplink subframe scheduling when a subframe is bundled, including a scheduling unit, is configured to: when an uplink subframe bundling function is enabled for a terminal, according to an uplink/downlink slot ratio relationship, the number of fixed subframes per interval is The terminal performs an uplink time slot scheduling.

The scheduling unit is further configured to: initiate an uplink subframe bundling function for the terminal, Recognize.

Wherein, the system further comprises a secondary decision unit;

When the scheduling unit initiates the acknowledgment, the method is configured to: determine, according to the uplink channel quality of the terminal, whether the uplink subframe bundling function of the terminal is enabled, and notify the second-level decision unit of the determination result; The decision unit finally decides whether the uplink subframe bundling function is enabled, and notifies the scheduling unit of the final decision result.

The secondary decision unit is further configured to notify the terminal of the final decision result: the secondary decision unit sends a reconfiguration message to notify the terminal whether the uplink subframe bundling function is enabled.

The secondary decision unit is an RRC layer.

The scheduling unit performs the scheduling according to the uplink-downlink slot ratio relationship, and is configured to: enter a subframe bundling special scheduling mode, and control the scheduler according to algorithm parameters configured by the background, and current communication mode and uplink and downlink The gap ratio relationship, the number of subframes fixed every interval is an uplink time slot scheduling for the terminal.

The scheduling unit is a MAC layer.

The technology for implementing the uplink subframe scheduling in the subframe binding of the present invention, for the uplink subframe bundling application, by scheduling the uplink subframes in a fixed cycle, effectively reduces the overhead required for uplink scheduling of the terminal. Moreover, the scheduling period can be dynamically configured in the background, which improves the flexibility of the implementation of the subframe bundling function. DRAWINGS

FIG. 1 is a flowchart of implementing uplink subframe scheduling when a subframe is bundled according to an embodiment of the present invention; FIG. 2 is a schematic flowchart of implementing uplink subframe scheduling when a subframe is bundled according to an embodiment of the present invention. detailed description

For the uplink subframe bundling function in the uplink scheduling of the MAC (Medium Access Control) layer in the LTE system, the present invention proposes to implement uplink when a seed frame is bundled. Subframe scheduling technique. In general, through a large number of simulation experiments, it is found that in the uplink subframe bundling mode, the period in which the base station sends an uplink scheduling instruction to the same terminal follows a certain rule. Therefore, according to the TDD uplink and downlink slot ratio relationship, the functional entity such as the MAC layer determines whether the terminal can transmit data on the PUSCH according to the currently scheduled subframe number.

Specifically, the operation shown in Figure 1 can be performed:

1. In the background cell configuration, configure the algorithm parameters corresponding to 0, 1, and 6 of the TDD uplink and downlink time slot. This parameter indicates the uplink subframe scheduling period. Configure the current cell to enable the uplink subframe binding function.

2. The MAC layer determines whether the uplink subframe bundling function of the terminal can be enabled according to the uplink channel quality of the terminal. The judgment result is notified to the RRC (Radio Resource Control) layer.

3. After receiving the subframe bundling judgment result sent by the MAC layer, the RRC layer performs a decision according to the algorithm to determine whether the uplink subframe bundling function is enabled, and notifies the PHY (physical) layer, the MAC layer, and the terminal of the final decision result. . The method for notifying the terminal may be to send an RRC reconfiguration message to notify the terminal whether the uplink subframe bundling function is enabled. The RRC layer may be referred to as a secondary decision unit.

4. When the uplink subframe bundling function is enabled, the MAC layer enters the subframe bundling special scheduling mode, and the control scheduler is fixed according to the algorithm parameters configured by the background, and the current communication mode and the uplink-downlink slot ratio relationship. The number of subframes is an uplink time slot scheduling for the terminal.

In practical applications, the following operations can be performed:

1. In the background cell configuration, the communication mode is set to TDD and the uplink and downlink time slot ratio is 0. The corresponding algorithm parameters are configured to indicate the scheduling period of the PUSCH when the uplink subframe bundling function is enabled in the current cell configuration.

2. The MAC layer determines whether the uplink subframe bundling function is enabled according to the uplink channel quality of the terminal, and finally determines the uplink subframe bundling function of the enabled terminal, and notifies the RRC layer of the situation, for example, sending an uplink subframe bundling function enable message. . After receiving the uplink subframe bundling function enable message sent by the MAC layer, the RRC layer enables the uplink subframe bundling function according to the algorithm decision, and notifies the PHY layer, the MAC layer, and the terminal of the decision result, and the method for notifying the terminal The RRC reconfiguration message may be sent to notify the terminal whether the uplink subframe bundling function is enabled.

4. The MAC layer determines whether the subframe binding enable flag is included in the decision result sent by the RRC layer, and includes confirming that the uplink subframe bundling function is enabled and performing step 5, otherwise confirming that the uplink subframe bundling function is not enabled and executing Step 6.

5. If the current uplink subframe scheduling time after the subframe is bundled, the HARQ process can be immediately allocated, and the RB (Resource Block) and PHICH resources are allocated; otherwise, according to the periodic scheduling, the scheduling period is based on the previous The algorithm parameters configured in the background, in ΤΉ. End the process.

6, normal scheduling.

As shown in the above description, the operation of implementing the uplink subframe scheduling in the subframe bundling of the present invention may represent the process shown in FIG. 2, and the process includes the following steps:

Step 210: The MAC layer initiates confirmation of the uplink subframe bundling function of the terminal. Of course, in practical applications, the confirmation can also be initiated by other functional entities.

Step 220: When the uplink subframe bundling function is enabled, the MAC layer performs an uplink time slot scheduling for the terminal according to the uplink-downlink slot ratio relationship, and the number of fixed subframes is fixed. Of course, in actual applications, the scheduling may also be performed by other functional entities, and the functional entities performing the scheduling may be collectively referred to as a scheduling unit.

In summary, the method for implementing the uplink subframe scheduling in the subframe binding of the present invention is applicable to the uplink subframe binding application, and the uplink subframe is scheduled in a fixed cycle, thereby effectively reducing the terminal. The overhead required for upstream scheduling. Moreover, the scheduling period can be dynamically configured by the background, which improves the flexibility of the implementation of the subframe bundling function.

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

Claims

Claim

2. The method according to claim 1, wherein the method further comprises: initiating confirmation by the medium access control MAC layer for the uplink subframe bundling function of the terminal.

3. The method according to claim 2, wherein the process of the MAC layer initiating the confirmation comprises:

4. The method according to claim 3, wherein the RRC layer also informs the terminal of the final decision result: The RRC layer sends an RRC reconfiguration message to notify the terminal whether the uplink subframe bundling function is enabled.

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dagger.

The method according to any one of claims 1 to 4, wherein the method for performing the scheduling according to the uplink-downlink slot ratio relationship is:

A system for implementing uplink subframe scheduling when a subframe is bundled, comprising a scheduling unit, configured to: when an uplink subframe bundling function for a terminal is enabled, according to an uplink and downlink slot ratio relationship, a fixed subframe per interval The number is an uplink time slot scheduling for the terminal.

The system according to claim 6, wherein the scheduling unit is further configured to: initiate an acknowledgement of an uplink subframe bundling function of the terminal.

8. The system of claim 7, wherein the system further comprises a secondary decision unit; When the scheduling unit initiates the acknowledgment, the method is configured to: determine, according to the uplink channel quality of the terminal, whether the uplink subframe bundling function of the terminal is enabled, and notify the second-level decision unit of the determination result; The decision unit finally decides whether the uplink subframe bundling function is enabled, and notifies the scheduling unit of the final decision result.

The system according to claim 8, wherein the secondary decision unit is further configured to notify the terminal of the final decision result: the secondary decision unit sends a reconfiguration message to notify the terminal whether the uplink subframe is enabled. Bundle function.

10. The system of claim 8, wherein the secondary decision unit is an RRC layer.

The system according to any one of claims 6 to 10, wherein, when the scheduling unit performs the scheduling according to the uplink-downlink slot ratio relationship, it is used to:

12. The system according to claim 6, wherein the scheduling unit is a MAC layer.