ES2589477T3 - Uplink HARQ feedback channel design for carrier aggregation in OFDMA systems - Google Patents

Abstract

A method comprising: receiving a configuration message from the upper layer of an eNB (502) by a user equipment, UE, (501) in a multi-carrier wireless communication network with carrier aggregation, CA; receive one or more downlink concessions, DL, from the eNB (502); determine a HARQ feedback format based on the UE capacity of the maximum number of component carriers, CCs, supported, with the result of detection of the DL concessions received, and the configuration of the upper layer; and transmitting HARQ feedback information using the determined HARQ feedback format, characterized in that the method further comprises decoding in the eNB (502) of the HARQ feedback information using the HARQ feedback format, and because depending on the number of CCs required to be supported by the UE (501), the UE (501) uses a simple CC, a non-CA format, and wherein the UE (501) supports a simple CC; or the UE (501) changes to a simple CC, a non-CA format, where the UE (501) supports more than one CC, and where only one CC is configured by the upper layer; or the UE (501) changes to CA with a small payload size, a CA-S format, where the UE (501) supports up to two CCs, where two CCs are configured by the upper layer, and where the UE (501) detects at least one DL grant for the transmission of data on a secondary CC, SCC; or the UE (501) changes to the CA with large payload size, a CA-L format, where the UE (501) supports up to five CCs, where more than one CC is configured by the upper layer, and where the UE (501) detects at least one DL grant for the transmission of data on a secondary CC, SCC; or the UE (501) changes to a simple CC, a non-CA format in backward mode, where the UE (501) supports more than one CC, where more than one CCs is configured by the upper layer, and where the UE (501) detects only one DL grant for the transmission of data on a primary CC, PCC.

Description

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DESCRIPTION

Uplink HARQ feedback channel design for carrier aggregation in OFDMA systems.

Cross reference with related applications

This application claims priority under 35 USC §119 of the Provisional Application of the United States Number 61 / 356,081, entitled "Design of the Upstream Link HARQ Feedback Channel for Carrier Aggregation in OFDMA Systems", filed on June 18, 2010 ; U.S. Provisional Application Number 61 / 373,351, entitled "Upstream Link HARQ Feedback Channel Design for Carrier Aggregation in OFDMA Systems", filed on August 13, 2010; U.S. Provisional Application Number 61 / 390,064, entitled "Resource Assignment for Upstream Link HARQ Feedback Channel for Carrier Aggregation in OFDMA TDD / FDD Systems", filed October 5, 2010.

Field of the Invention

The disclosed claims relate in general to wireless network communications, and, more particularly, to the design of the uplink HARQ feedback channel and to the allocation of the resource for carrier aggregation in OFDMA systems.

Background of the invention

A Long-Term Evolution (LTE) system offers high peak data rates, low latency, improved system capacity, and low operating costs as a result of a simple network architecture. An LTE system also provides seamless integration to an older wireless network, such as GSM, CDMA and the Universal Mobile Telecommunication System (UMTS). In LTE systems, an evolved universal terrestrial radio access network (E-UTRAN) includes a variety of evolved Nodes-Bs (eNBs) that communicate with a variety of mobile stations, referred to as user equipment (UEs).

An LTE system uses a hybrid automatic repeat request (HARQ) as its physical layer (PHY) to improve the quality of data transmission while controlling the procedure by Media Access Control (MAC) or higher layers . The HARQ is an error correction mechanism that combines forward error control (FEC) and automatic repeat request (ARQ). On the transmitting side, the error detection bits are added to the transmission data. The receiver decodes the received bits and sends a positive acknowledgment (ACK) or a negative acknowledgment (NACK) back to the transmitter based on whether the transmitted data can be decoded correctly. The receiver sends the ACK or NACK defining the corresponding bit (s) on a reverse control channel. In particular, the LTE system, upon receiving the downlink data of an eNB, a UE can send the HARQ feedback information to the eNB through a Physical Uplink Link Control Channel (PUCCH). The current PUCCH supports up to 4 bits of HARQ feedback information. The HARQ process improves system performance. However, problems arise for the design of the existing HARQ feedback channel with improvements to the LTE system.

Improvements to the LTE system (LTE advance system) are considered to meet or exceed the fourth generation (4G) International Advanced Mobile Telecommunications (IMT-advanced) standard. One of the keys to improvements is to support bandwidth up to 100 MHz and be backward compatible with wireless network systems. Carrier aggregation (CA) is introduced to improve system performance. With carrier aggregation, the LTE-advanced system can support peak data rates in excess of 1 Gbps in the downlink (DL) and 500 Mbps in the uplink (UL). Such technology is attractive because it allows operators to add various contiguous or non-contiguous smaller carrier components to provide a larger system bandwidth, and provide backward compatibility allowing legacy users to access the system using one of the components. of carriers.

In a mobile network, a UE's broadband requirement changes with the amount of data that the UE transmits or receives. Carrier aggregation allows the mobile network to use broadband more efficiently. In particular, bearer aggregation allows an asymmetric number of uplink and downlink component carriers for each UE. For example, a UE with multiple CC capacity can be configured to have five component carriers and only one UL component carrier in the Frequency Division Duplex (FDD) system; or five DL portions and only one UL portion in the Time Division Duplex (TDD) system. Due to asymmetric UL and DL CC configuration, the uplink HARQ payload size increases significantly. For example, if five DL component bearers are configured, up to 12 bits are required to carry the HARQ feedback information for FDD, and up to 47 bits are required for TDD. The current non-CA PUCCH channel format, however, only supports up to 4 bits for HARQ feedback information.

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Therefore, at least one PUCCH channel format is required for uplink HARQ information. To be regressively compatible, the LTE system needs to support both the uplink CA HARQ non-uplink format and the new CA HARQ uplink format. In addition, the non-CA HARQ uplink format has a better efficiency in the use of resources, while the CA HARQ format is less efficient. Depending on the application scenario, it is therefore desired that the HARQ feedback channel format applied, change according to achieve a better efficiency in the use of the resource. However, the uplink is unreliable and controls messages and data may be lost during transmission. This will result in a mismatch of information between UEs and eNBs. Blind decoding on the eNB side introduces a higher calculation complexity and performance degradation. To solve the problem, a HARQ format synchronization scheme between UEs and eNBs is required. A rule for switching the HARQ format is required at the same time in the UEs and in the eNBs.

Another problem for the design of the HARQ feedback channel in an LTE-advanced system is the allocation of physical resource 5 for the uplink HARQ. Due to the asymmetry of the UL and DL carrier components for a UE, there may be only one HARQ feedback channel in a specific UL component carrier for multiple programmed transport blocks (TBs) in more than one DL CCs. Therefore, the implicit resource assignment based on the current non-CA cannot be used, which depends on the logical address of the downlink programmer. The implicit resource allocation will create multiple candidate resource assignments for feedback due to multiple DL programmers in the same programming period (for example, a subframe in LTE). Due to the unreliable decoded results, an eNB does not know which resource location a UE will apply and therefore has to reserve all candidate resource assignments. A solution was sought to allocate the resource for the HARQ feedback channel more efficiently for the CA mode.

MOTOROLA: "Uplink ACK / NACK Transmission Format for Carrier Aggregation", 3GPP Draft; R1-103157, 3rd Generation Partnership Project (3GPP), Mobile Competence Center; 650, route des Lucioles; F-06921 Sophia-Antipolis Cedex; France, Vol: RAN WG1, no. Montreal, Canada; 20100510 belongs to the draft Project of the 3rd generation Association (3GPP) related to the subject of its title.

MOTOROLA: "Uplink ACK / NACK Transmission Format for Carrier Aggregation", 3GPP Draft; R1-103157, 3rd Generation Partnership Project (3GPP), Mobile Competence Center; 650, route des Lucioles; F-06921 Sophia-Antipolis Cedex; France, Vol: RAN WG1, no. Montreal, Canada; 20100510 belongs to the draft Project of the 3rd generation Association (3GPP) related to the subject of its title.

WO2010 / 068069 A2 belongs to a method and apparatus for detecting a control channel in a multi-carrier broadband wireless access system and more particularly, with the reduction of the blind decoding complexity of a user equipment in the detection of a control channel

WO2010 / 050754 A2 belongs to a wireless access system, and more particularly with an effective transmission method of a control channel in a multi-carrier aggregation state.

Summary of the invention

The object is solved by a method according to claim 1 and 3, respectively, and a user equipment according to claim 2 and a base station according to claim 4, which implements said methods.

The design of the HARQ feedback channel for carrier aggregation (CA) is proposed in an LTE / LTE-A multi-carrier system. In a new aspect, a predefined rule for switching the format of the HARQ feedback channel is adopted by the system. Different HARQ formats are supported: single component carrier mode (non-CA), carrier aggregation mode with small payload size (CA-S), carrier aggregation mode with large payload size (CA -L), and a reverse mode. From various CA and non-CA formats, the format for using the uplink HARQ feedback channel is determined based on the following factors: UE capacity for the maximum number of supported CCs; CC configuration information by the radio resource configuration layer (RRC); and detection results of downlink programmers. The CC configuration information may include the number of CCs that are configured by the RRC, and a specific HARQ format to use. Because the most reliable upper configuration layer is used to make the HARQ format-switching decision, the risk of UE and eNB mismatch is greatly reduced.

In another new aspect, a HARQ feedback channel resource allocation scheme is adopted by the system. Two resource allocation schemes (for example, explicit and hybrid) are applied for HARQ ACK / NACK (A / N). Part of the resources are allocated based on the explicit method through the RRC configuration. Another part of the resources are allocated based on the hybrid method using both the RRC and

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the implicit information made by downlink programmers. In an explicit method, the physical resource for the physical A / N resource is determined based on a Resource Index in a DL programming concession. The DL concession corresponds to transport blocks on a configured CC. The Resource Index points to a physical resource from a set of physical resources of A / N uplink candidates reserved for the CC. If the DL transmission mode is configured as a dual code word (CW), then a second physical A / N resource is determined by applying compensation to the Resource Index. In an implicit method, physical A / N resources are determined based on a logical address of the DL programming concession. In one embodiment, the implicit and explicit resource allocation is applied in a dynamic DL programming scheme. In another embodiment, the implicit resource assignments are applied in a semi-persistent programming DL (SPS) programming scheme.

Other embodiments and advantages are described below in the detailed description. This summary does not mean that you define the invention. The invention is defined by the claims.

Brief description of the drawings

The accompanying drawings, where, like the numerals, they also indicate the components, illustrate the embodiments of the invention.

Figure 1 illustrates a request for automatic hybrid repetition of the feedback channel design (HARQ) in a 100 LTE-A system in accordance with a new aspect.

Figure 2 illustrates an example wireless communication system comprising a user terminal and a base station according to a new aspect.

Figure 3 shows the set of HARQ FDD formats, the range of the number of supported HARQ bits, and their possible mapping to the existing or new PUCCH format.

Figure 4 shows the set of HARQ TDD formats, the range of the number of supported HARQ bits, and their possible mapping to the existing or new PUCCH format.

Figure 5 illustrates a synchronization method of the uplink HARQ format according to a new aspect.

Figure 6 illustrates a specific eNB implementation to solve the uplink HARQ format switching problem.

Figure 7 illustrates a specific UE implementation to solve the uplink HARQ format switching problem.

Figure 8A illustrates an implicit resource allocation scheme for non-cross CC programming.

Figure 8B illustrates an implicit resource allocation scheme for cross CC programming.

Figure 9 illustrates a joint allocation of the resource by the upper layer control.

Figure 10 illustrates a method of assigning the HARQ resource according to a new aspect.

Figure 11 shows the implementation stages of a dynamic resource allocation method.

Figure 12 illustrates a specific example of a dynamic resource allocation method.

Figure 13 shows the stages of implementation of the method of allocation of the SPS resource.

Figure 14 illustrates a specific example of an SPS resource allocation method.

Figure 15 illustrates a specific example of a hybrid resource allocation method.

Detailed description

Reference is now made in detail in some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

Figure 1 illustrates a hybrid automatic repeat request (HARQ) feedback design in a 100 LTE-A system in accordance with a new aspect. The 100 LTE-A system comprises a UE101 and an eNB102, both support channel aggregation (CA) on multiple component carriers (CCs). On a wireless downlink channel 103, the eNB102 transmits one or multiple downlink (DL) concessions

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to UE101. In a downlink wireless channel 104, the UE141 responds with uplink (UL) HARQ feedback information to the eNB102. There is more than one format in the system to support the HARQ feedback channel at the same time for non-CA mode and CA mode (for example, non-CA format, 1 CA format, and 2 CA format). Due to the lack of reliability of the wireless channel, UE101 and eNB102 may have different understandings about which format is applied. Additionally, because multiple DL component carriers are supported, there may be only one HARQ feedback channel in a specific UL CC for multiple transport blocks programmed in more than one DL CCs. Due to the unreliable decoding results of DL programmers, the eNB102 has no idea which resource location UE 101 will apply for the HARQ feedback channel (for example, physical location 105-108). In a new aspect, a HARQ format synchronization scheme is defined between the UE101 and the eNB102. More specifically, one format switching rule is predefined at the same time in UE101 and in eNB102. In another new aspect, a HARQ resource allocation scheme is defined for the CA mode at the same time in UE101 and in eNB102.

Figure 2 illustrates simplified block diagrams of an example wireless communication terminal UE201 and an eNB202 base station. The UE201 and the eNB202 can operate following any communication protocol. For illustrative purposes, the disclosed embodiment operates in accordance with the LTE protocol. The UE201 comprises a transceiver antenna 210 coupled to an RF module 211. The transceiver antenna 210 receives or transmits the RF signals. Although only one antenna is shown for the UE201, it is known to those skilled in the art that wireless terminals may have multiple antennas for transmission and reception. The module 211 RF receives signals from either the transceiver antenna 210 or the baseband module 212, and converts the received signals into the baseband frequency. The baseband module 212 processes the signals transmitted from, or received by the UE201. Such processing includes, for example, modulation / demodulation, coding / decoding of the channel and encoding / decoding of the source. The UE201 further comprises the processor 213 that processes the digital signals and provides other control functionalities. Memory 214 stores the program instructions and data to control the operations of UE201. Similarly, the eNB202 comprises a transceiver antenna 230 coupled to an RF module 231, a baseband module 232, a processor 233, and a memory 234.

The UE201 and the eNB202 communicate with each other by means of a common defined layered protocol stack 215. Layer 215 of the layered protocols includes layer 216 of Non-Access Stratum (NAS), which is the protocol between a UE and a mobility management entity (MME) to provide upper layer network control, layer 217 Radio Resource Control (RRC), Layer 218 of Package Data Convergence Control (PDCP), Layer 219 of Radio Link Control (RLC), Layer 220 of Media Access Control (MAC) , and the physical layer 221 (PHY). The different modules and the modules of the protocol layer can be function modules or logical entities, they can be implemented by software, firmware, hardware, or any combination of these. The different modules work together, when executed by the processor, allowing the UE201 and the eNB202 to carry out various communication activities.

In particular, the LTE system uses HARQ in the PHY layer to improve the quality of data transmission (for example, soft combination and feedback information via 205), while the HARQ procedure is controlled by the MAC or layers. higher (for example, the procedure for feedback and retransmission information via 204). The additional configuration information for the HARQ feedback channel is controlled by the upper layer (for example, RRC 203). In the layered protocol 215, the transmission of PHY layer data and the MAC layer control messages are less reliable than the upper layer control messages of the layered protocol, in one embodiment of the invention, the information of upper layer configuration to synchronize HARQ formats between UE201 and eNB202 and to allocate the HARQ resource.

HARQ format switching

As shown in Figure 2, the HARQ information is exchanged in the MAC layer. The current LTE supports various channel formats for the transmission of HARQ feedback information in the PHY layer, up to a maximum of 4 bits. In LTE-A systems, existing formats do not support enough bits of HARQ information when multiple DL CCs are configured under carrier aggregation. New formats are needed for HARQ feedback information. To support more than two DL CCs configured, at least one new HARQ channel format is required. Figure 3 and Figure 4 show, in one embodiment of the invention, a set of HARQ channel formats proposed for FDD and TDD respectively.

Figure 3 shows, in one embodiment of the invention for FDD, the set of HARQ formats, the range of the number of supported HARQ bits, and their possible mapping to the existing or new PUCCH format. The FDD non-CA format supports less than or equal to two HARQ bits in the uplink feedback information, and uses the LTE 8/9 launch PUCCH format 1a / 1b. The small payload format (CA-S) of FDD carrier aggregation supports more than two and less than or equal to four HARQ bits in the feedback information of

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uplink, and takes the form of the 1b PUCCH format with the channel selection. The large payload format (CA-L) of FDD carrier aggregation supports more than two HARQ bits in the uplink feedback information, and takes the form of PUCCH Format 3 based on the DFT-S-OFDM.

Figure 4 shows, in one embodiment of the invention, the set of HARQ formats for TDD, the range of the number of supported HARQ bits, and their possible mapping to the existing or new PUCCH format. The non-CA TDD format supports less than or equal to four HARQ bits in the uplink feedback information, and uses the 1 a / 1 b PUCCH launch LTE 8/9 format or the PUCCH 1b format with channel selection. The small payload (CA-S) format of TDD carrier aggregation supports more than two and less than or equal to four HARQ bits in the uplink feedback information, and takes the form of the 1b PUCCH format with channel selection using the CA mapping table. The large payload format (CA-L) of TDD carrier aggregation supports more than four bits of HARQ in the uplink feedback information, and takes the form of the 3 PUCCH format based on the DFT-S-OFDM.

Figure 3 and Figure 4 are sample channel formats that contain HARQ information to support carrier aggregation. Due to the asymmetric DL and the UL CC configuration, a new HARQ format is required. The format with increased payload for HARQ feedback information makes the system less efficient in utilizing the uplink resource. Therefore, the UE and the eNB should be able to switch the format based on the application scenario. Problems occur when control messages from the less reliable MAC or PHY layer are lost or not recovered correctly. Said control messages include DL concession messages that dynamically program the transmission of data for a CC, which is activated by the MAC or a higher layer. For example, an eNB sends three downlink concessions to a UE. The eNB based on the three DL concessions sent, expects the HARQ feedback from the receiving UE in the CA-L format as defined in Figure 3 and Figure 4. Since the PHY or MAC layer is a message channel less reliable control, the UE can receive only two concessions. The UE analyzes the information and makes the decision as to whether the uplink HARQ format is justified. Since the UE only receives two DL grants, it discovers that the required HARQ bits are less than or equal to four. Therefore, the UE sends the uplink HARQ information using the CA-S format. The format used by the UE, based on its DL concession received, is different than what the eNB sender expects. A mismatch of HARQ format occurs between the eNB and the UE. To solve the problem, a default scheme is required to synchronize the UE and the eNB in the uplink HARQ format switching.

Figure 5 shows an embodiment of the invention that solves the problem of mismatch. In step 510, the eNB 502 sends semi-static CC configuration data via an upper layer control channel (for example, the RRC) to the UE 501. The CC configuration data may include the number of CCs that are configured by the RRC , and a specific HARQ format to be used. This upper layer control channel is more reliable than the lower layer, such as the PHY or the MAC layer. In step 520, the UE 501 receives this upper layer control message and uses it to make the decision in the HARQ format. In step 511, the eNB 502 sends a variety of DL grants through either the MAC layer or the Physical Downlink Link Control Channel (PDCCH). Such concession (s) may also be lost due to errors or losses in unreliable lower layer control messages. Upon receiving the diversity of DL concessions, in step 521, the UE 501 determines whether the switching of the HARQ format is required. In an embodiment of the invention, this decision is made in step 522 based on the following information: 1) the capacity of UE 501 of the maximum number of CC supported; 2) the CC configuration of the upper layer received from eNB 502 in step 510; and 3) the detection results of the DL programmer in the UE 501. In step 512, the UE 501 sends the HARQ feedback information with the corresponding format based on the decision taken in step 522. Upon receiving the feedback information HARQ, the eNB502 decodes the information using the corresponding format in step 513. Because the most reliable upper layer configuration is used to make the HARQ format switching decision, the UE and eNB mismatch is greatly reduced.

Figure 6 shows an embodiment of the eNB implementation of the algorithm in Figure 5 in the FDD system. For a UE that supports AC, in step 601, the eNB first considers whether the UE has the capacity to support more than two CCs. If not, in step 602, the eNB further checks if the upper layer configures the UE with more than one CC. If not, in eNB it puts this UE in a simple 607 CC mode, and uses the 610 non-CA format for HARQ feedback. If yes, the eNB will enter state 606: the AC with small payload size mode or reverse mode. If the backward mode is activated due to downlink programmer detection for only the PCC, then the non-CA 610 format is used for the uplink HARQ feedback; otherwise, the CA, with the small payload size mode is activated and the 609 CA-S format is used for HARQ uplink feedback.

In step 601, if the eNB determines that the UE supports more than two CCs, then the eNB continues to step 603. In step 603, the eNB checks if the upper layer configures the UE with less than 2 CCs. If not, the eNB enters the state

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605: AC with large payload size mode or reverse mode. If the backward mode is activated due to downlink programmer detection for the PCC only, then non-CA 610 format is used for uplink HARQ feedback; otherwise, the CA is activated with the large payload size mode and the CA-L 608 format is used for HARQ uplink feedback. If in step 603, the eNB finds that there are less than two CCs configured for the UE, the HARQ mode for the UE also depends on other configuration information of the upper layer. In one embodiment of the invention, the eNB verifies if the UE is configured with CA-S format in step 604. If the CA-S format is configured for the UE, the eNB will enter state 606: AC with the mode of Small payload size or recoil mode. If backward mode is activated due to downlink programmer detection for the PCC only, then non-CA 610 format is used for uplink HARQ feedback; otherwise the CA is activated with the small payload size mode and the 609 CA-S format is used for HARQ uplink feedback. On the other hand, if the CA-L format for the UE is configured in step 604, the eNB enters state 605: the CA with the large payload size mode or recoil mode. If backward mode is activated due to downlink programmer detection for the PCC only, then non-CA 610 format is used for uplink HARQ feedback; otherwise, the CA is activated with large payload size and the 608 CA-L format is used for HARQ uplink feedback.

Figure 7 shows an embodiment of the UE implementation of the algorithm in Figure 5 in the TDD system. In the example of Figure 7, a UE may decide the HARQ format based on the information in step 522 in Figure 5 by first categorizing the HARQ format mode. As shown in Figure 7, in step 701, the UE first considers the capacity of the maximum number of CCs supported by this UE. If the UE can only support one CC, then the HARQ feedback format of the UE is a simple 709 CC mode. The UE should use the 712 non-CA format for uplink HARQ feedback in PUCCH. If step 701 determines that the UE has the capacity to support more than one CC, then the UE then checks in its upper layer configuration to decide if more than one CC has been configured in step 702. If there is only one CC configured by The top layer, although the UE can support more than one CC, the UE still follows a simple 709 CC mode and uses a 712 non-CA format. On the other hand, if step 702 determines that more than one CCs has been configured for this UE, then the decision of which HARQ format mode to use will additionally depend on the detection of the DL programmer in step 703. If the UE only detects the programmer for the Primary Component Carrier (PCC), the UE will define its HARQ format to backlash mode 708. If the UE is in the backward mode for the uplink HARQ feedback, the HARQ non-CA 712 feedback format should be used for HARQ feedback information.

If at step 703, there is at least one DL programmer for the Secondary Component Carrier (SCC), then the UE continues to step 704. If at step 704, there are less than or equal to four DL programmers detected, then with Based on the upper layer configuration, the UE will define any AC with a small size payload 706 mode or a CA with a large size payload 707 mode. In one embodiment, in step 705, the UE will verify if the CA-S format is configured by the upper RRC layer for uplink HARQ feedback. If the CA-S format is configured for this UE, then the UE is defined to the CA with small size payload mode 706, and uses the 710 HARQ CA-S feedback format. Otherwise, the UE is defined to the CA with the 707 large-size payload mode, and uses the 711 HARQ CAL feedback format. If in step 704, there are more than four DL programmers detected, then the UE is defined to the CA with the large size payload 707 mode, and uses the 711 HARQ CA-L feedback format.

Figure 6 and Figure 7 show example implementations based on the methods of Figure 5 to solve the problem of switching the HARQ format. Considering the combination of the maximum CC capacity UE, the upper layer CC configuration information, and the detection results of the DL programmers, the UE has less risk of exposure to the unreliable lower layer control channel. This makes the format switching more efficient.

Resource Assignment

Another problem related to the uplink HARQ in an LTE-advanced system is the resource allocation for the HARQ feedback channel. The existing non-CA-based system uses implicit resource allocation based on the logical direction of the downlink programmer. This implicit method does not work in an enabled CA system. This is because multiple DL component carriers can be supported with only one UL component carrier. As a result, there may be only one HARQ feedback channel in a specific UL component carrier for multiple transport blocks programmed in more than one of the DL component carriers. In addition, due to the unreliable decoding results of the downlink programmer, the eNB does not know which physical resource EU will apply for HARQ feedback. Problems with resource allocation may occur when any of the control messages are lost due to the unreliable wireless channel. For example, an eNB sends three DL grants: G1, G2, and G3 to a UE. The eNB does not know

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which EU resource to choose, and will have to reserve all possible physical resources. This is not an efficient way to allocate the HARQ uplink resource. Consequently, a more efficient resource allocation scheme is necessary.

In addition, the non-CA based implicit resource allocation scheme cannot be used in a CA-enabled system, especially when multiple DL component bearers are configured with only one UL component bearer. The implicit resource allocation scheme determines the physical resources ACK / NACK (A / N) uplink implicitly based on the logical direction of the PCC downlink programming concession. Figure 8A and Figure 8B illustrate examples of the implicit resource allocation scheme.

Figure 8A shows an implicit resource allocation with a non-cross CC programming scheme. There are three CCs that are used for the UE. Each of the three CCs has its own control field that points to its transport block (TB). In a non-CA mode, the physical resource for uplink A / N feedback is implicitly allocated using the logical 802 address of the uplink programming concession. This logical address points to a physical resource 801, which is the physical resource for uplink A / N feedback.

Figure 8B shows an implicit resource assignment with a cross CC programming scheme. Three CCs (CC # 1, CC # 2 and CC # 3) are used for the UE. CC # 2 has three control fields that program the three CCs. Control field 813 points to CC # 1, control field 814 points to CC # 2, and control field 815 points to CC # 3. In a non-CA mode, the physical resource is implicitly assigned using the 812 logical address of the downlink programming concession. This logical address points to a physical resource 811, which is the physical resource for uplink physical A / N feedback.

Another type of uplink A / N physical resource allocation method is illustrated in Figure 9 where an upper layer channel, such as an RRC, configures multiple sets of the physical resource for uplink A / N feedback. A set of uplink physical A / N resources is reserved for each CC configured by an upper layer channel. For example, if there are two CCs configured, two sets of physical uplink A / N resources are reserved. Different sets of the physical uplink A / N resource may be the same. In addition, multiple UEs can share the same set of physical uplink A / N resource on each configured CC.

Figure 9 illustrates this resource allocation managed by an upper layer control. The eNB 903 configures the CC and physical A / N resources through an upper layer such as an RRC signal. In step 913, the RRC sends the CC configuration and the uplink A / N physical resource configuration information to the UE 901. In step 914 the eNB sends the CC configuration and the A / N physical resource configuration information. uplink to UE 902. For UE 901, two CCs are configured, UE1-CC1 and UE1-CC2. Two separate sets of physical uplink A / N resources 910 and 911 are reserved for UE1-CC1 and UE1-CC2 respectively. UE1-CC1 points to 910 and UE2-CC2 points to 911. Similarly, UE 902 is configured with three CCS: UE-CC1, UE2-CC2 and UE2-CC3. Two sets of physical uplink resources 911 and 912 A / N pool for UE 902 are reserved. UE2-CC1 points to a 911 uplink A / N resource, which is shared with a different UE, the UE 901. The UE2-CC2 and the UE2-CC3 both point to the uplink 912 A / N resource, where they share the same physical uplink A / N resource.

Figure 10 illustrates a method of assigning the HARQ resource according to a new aspect. In step 1003, the eNB1002 reserves a set of uplink A / N physical resources candidate for a CC configured for UE1001. In step 1004, the eNB1002 transmits a DL programming concession to the UE1001. The DL concession corresponds to the transport blocks on the configured CC. In step 1005, the UE1001 receives the DL programming concession and determines an A / N physical resource. The physical resource A / N is determined based on a Resource Index in the DL grant. The Resource Index corresponds to a physical resource of the candidate's set of physical resources A / N reserved for the CC. If the DL transmission mode is configured as a dual code word, then a second physical A / N resource is determined by applying compensation to the Resource Index. In step 1006, the UE1001 sends HARQ feedback information through the determined physical A / N resource (s). In step 1007, the eNB1002 receives and decodes the HARQ feedback information of the physical A / N resource (s). In step 1008, the eNB1002 transmits a second DL programming concession to the UE1001. In step 1009, the UE1001 determines one or two physical A / N resources based on a logical address of the second DL programming concession. In step 1010, the UE1001 sends HARQ feedback information through either of the two physical A / N resources. Finally, in step 1011, the eNB1002 receives and decodes the HARQ feedback information from one or both physical A / N resources.

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There are two types of DL concessions that are discussed in the resource allocation methods: 1) dynamic DL programming concession, and 2) semi-persistent programming concession (SPS). The DL non-SPS programming concession requires that each DL or UL physical resource allocation (PRB) must be granted through an access concession message and the concession expires automatically in a transmission time interval (TTI). The SPS introduces a semi-persistent PRB assignment that a user should expect in the DL or that can be transmitted in the UL. An SPS concession will not automatically expire on a TTI. Instead, it will be terminated explicitly.

In one embodiment of the invention, a dynamic programming method is used for resource allocation of the CA-S format. In this method, a maximum of uplink physical A / N resources are determined implicitly based on the logical direction of the downlink programming concession corresponding to the transport blocks on the downlink PCC. The explicit logical address scheme is as shown in Figures 8A-8B. If the downlink programming concession for the PCC is configured as a single code word, only a physical uplink A / N resource is determined implicitly based on a logical address of the downlink programming concession. The physical uplink A / N resources required are explicitly determined by the downlink programming concessions corresponding to the transport blocks on the downlink SCCs. This method can be applied at the same time to the CC cross and CC no cross programming. This also applies to both the FDD and TDD.

Figure 11 illustrates the implementation of the dynamic programming method. In step 1101, the UE first checks if it is for the CCP. If yes, in step 1102, it verifies if the PCC is configured as a dual code word. If this is not a dual code word, it continues to step 1104 and determines implicitly based on the logical address of the downlink programming concession corresponding to the transport blocks on the downlink PCC. On the other hand, if in step 1102 it determines that it is a dual code word, it continues to stages 1105 and 1108, where two uplink A / N resources are implicitly determined based on a logical address of the downlink programming concession in step 1105, and another is determined by applying the logical address plus compensation. If in step 1101, the UE determines that it is not a CCP, then the scheme moves to step 1103 to verify if the SCC is a dual code word. If in step 1103 this determines that it is not a dual code word, in step 1106, the physical uplink A / N resources required by the downlink programming concessions corresponding to the transport blocks are determined explicitly on downlink SCCs. The physical resource for this SCC will first be determined by the physical resource set configured by the upper layer as shown in Figure 10, A Resource Index in the downlink programming concession is applied to determine which candidate of the physical resource A / N uplink is used for A / N feedback on the joint reserved physical resource. If step 1103 determines that this is a dual code word, then it continues to stages 1107 and 1109. Step 1107 is the same as 1106 and this takes the physical resource for the word code 1. A second candidate is determined from Physical uplink A / N resource by applying compensation to the Resource Index in step 1109. The Resource Index plus the Compensation Index is used to determine which candidate of the uplink A / N physical resource is used for feedback A / N in the joint reserved physical resource.

Figure 12 further illustrates the method of allocation of the dynamic resource. As shown in Figure 12, the word code 1 DL PCC has a control field that contains programming for the code word 0 DL PCC, the code word 1 DL PCC, and the SCC # 0. By using this method, the physical uplink A / N resource for code word 0 DL PCC is implicitly determined based on the logical address in physical resource 1201 of the downlink programming concession for the DL PCC. Because the DL PCC is a dual code word, the physical uplink A / N resource for the code word 1 DL PCC is determined based on the logical address for the code word 0 DL PCC plus a compensation in the same resource 1201 physical. The physical uplink A / N resource for the remaining DL SCC # 0 is in the physical resource 1202 configured by the RRC signaling. The RRC configuration is as shown in Figure 10. The Resource Index in the downlink concession programming for the SCC is used to determine which candidate to use from the physical resource 1202.

In another embodiment of this invention, semi-persistent programming (SPS) is used for resource allocation. In this scheme, the physical uplink A / N resources required are explicitly determined by the downlink SPS activation concessions corresponding to the SPS transport blocks over CCs. A set of the physical resource is configured by the top layer signal with methods shown in Figure 10. A Resource Index is activated in the SPS activation grant to determine which candidate of the A / N physical resource is used for feedback. A / N If the downlink programming concession with dual code word transmission mode is applied for this CC, a second candidate of the uplink physical A / N resource is determined by applying compensation to the Resource Index.

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This method can be applied to either the CC cross and CC no cross programming. This can also be applied to either the FDD and the TDD.

Figure 13 shows the steps for the method of allocation of the SPS resource. In step 1301, this determines whether the DL programming concession with code word transmission mode is applied for this CC. If not, it moves to step 1302, where the Resource Index in the SPS activation concession is used to determine which candidate is used of the physical uplink A / N resource for A / N feedback. The physical resource set is reserved by the upper layer configuration as shown in Figure 10. If in step 1301 it determines that the word dual code applies to this CC, it moves to steps 1303 and 1304, where 1303 It is the same as 1302 the chosen candidate applies to the word code 0 for the A / N feedback. In step 1304, a second candidate of the uplink physical A / N resource is determined from the same physical resource by applying compensation to the SPS resource Index.

Figure 14 further illustrates the method of allocation of the SPS resource. As shown in Figure 14, three CCs are received in the UE. The PCC DL is configured as a dual code word and the DL SCC # 0 is not configured as a dual code word. The physical resource 1401 is reserved for the PCC by means of the RCC signaling using the method shown in Figure 10. The physical resource 1402 is reserved by the RRC signaling for the SCC # 0 using the method shown in Figure 10. The physical uplink A / N resource for code word 0 DL PCC is determined using the Resource Index in the SPS concession to choose from physical resource 1401. The physical uplink A / N resource for the code word 1 DL PCC is determined using the Resource Index in the SPS concession plus a compensation to choose it from the physical resource 1401. The physical uplink A / N resource for SCC # 0 is determined using the Resource Index in the SPS concession to choose it from physical resource 1402.

In other embodiments, hybrid methods can be used for resource allocation of the CA-S format. In one embodiment, the physical uplink A / N resources required are determined based on the dynamic resource allocation scheme. The remaining uplink A / N physical resources required are determined based on the allocation of the SPS resource. In another embodiment, a hybrid method can be used by applying the method of allocating the SPS resource to the PCC and using dynamic resource allocation to the others. Figure 15 illustrates said method. All these hybrid methods can be used at the same time for the CC cross and CC no cross programming. These can be applied at the same time for the FDD as! as for TDD.

Figure 15 illustrates a hybrid resource allocation method where SPS resource allocation is used for the PCC and dynamic resource allocation is used for the rest of the resource. Figure 15 shows a cross-CC programming with three CCs in subframe n: a code word 0 of the downlink primary carrier component (DL PCC CW0), a code 0 word of the downlink primary carrier component (DL PCC CW1), and a carrier # 0 downlink secondary component (DL SCC # 0). The DL PCC CW1 has the control programming fields for all three. A set of the physical uplink joint A / N resource 1501 is configured for the PCC by the upper layer by RRC signaling. A set of the physical uplink link A / N resource 1502 is configured for the SCC # 0 by the superior through RRC signaling. The Resource Index in the SPS activation concession for the PCC is applied to determine which candidate in 1501 of the physical upstream A / N resource is used for A / N feedback. A second candidate for the PCC is determined by applying compensation to the SPS Resource Index in the PCC to determine which candidate in 1501 of the physical A / N uplink resource is used for A / N feedback. The Resource Index in the DL concession for SCC # 0 is applied to determine which physical A / N resource is used in the joint physical resource 1502. Physical resources for A / N feedback are packaged in a UL PCC in the n + k sub-box. Another combination of hybrid methods can also be used to provide an efficient uplink A / N physical resource allocation.

Although the present invention has been described in connection with certain specific embodiments for instructional purposes, the present invention is limited thereto. For example, although an advanced LTE-mobile communication system is exemplified to describe the present invention, the present invention can be applied in a similar manner to all mobile communication systems based on carrier aggregation. Accordingly, various modifications, adaptations, and combinations of various features of the described embodiments can be practiced, without departing from the scope of the invention as set forth in the claims.

Claims (4)

5 10 fifteen twenty 25 30 35 40 Four. Five 1. A method comprising: receiving a configuration message from the upper layer of an eNB (502) by a user equipment, UE, (501) in a multi-carrier wireless communication network with carrier aggregation, CA; receive one or more downlink concessions, DL, from the eNB (502); determine a HARQ feedback format based on the EU capacity of the maximum number of component carriers, CCs, supported, resulting in detection of the DL concessions received, and the configuration of the upper layer; Y transmit HARQ feedback information using the determined HARQ feedback format, characterized in that the method further comprises decoding in the eNB (502) of the HARQ feedback information using the HARQ feedback format, and because depending on the number of CCs required to be supported by the UE (501), the UE (501) uses a simple CC, a non-CA format, and where the UE (501) supports a simple CC; or the UE (501) changes to a simple CC, a non-CA format, where the UE (501) supports more than one CC, and where only one CC is configured by the upper layer; or the UE (501) changes to CA with a small payload size, a CA-S format, where the UE (501) supports up to two CCs, where two CCs are configured by the upper layer, and where the UE (501) detects at least one DL concession for the transmission of data on a secondary CC, SCC; or the UE (501) changes to the CA with large payload size, a CA-L format, where the UE (501) supports up to five CCs, where more than one CC is configured by the upper layer, and where the UE (501) detects at least one DL concession for the transmission of data on a secondary CC, SCC; or the UE (501) changes to a simple CC, a non-CA format in backward mode, where the UE (501) supports more than one CC, where more than one CCs is configured by the upper layer, and where the UE (501) detects only one DL concession for the transmission of data on a primary CC, PCC. 2. A user equipment, UE, (201) comprising: a radio resource control layer module (217), RRC, adapted to receive a configuration message from an eNB (202); a module (221) of physical layer, PHY, or module (220) of media access control layer, MAC, adapted to receive one or more downlink concessions, DL, of the eNB (202) wherein the module ( 221) of PHY layer or MAC layer module (220) are adapted to determine a HARQ feedback format based on the UE capacity of the maximum number of CCs supported, the result of the detection of the DL concessions received, and the message Of configuration; and an antenna (210) adapted to transmit HARQ feedback information, where the HARQ feedback information was decoded using the determined HARQ feedback format, characterized in that the eNB (202) is adapted to decode the HARQ feedback information using the determined HARQ feedback format, and in which depending on the number of CCs required to be supported by the UE (201), the UE (201) is adapted to use a simple CC, non-CA format, and where the UE (201) supports a simple CC; or the UE (201) adapts to change to the simple CC, of non-CA format, where the UE (201) supports more than one CC, and where only one CC is configured by the upper layer; or the UE (210) adapts to change to the CA with small payload size, CA-S format, where the UE (201) supports up to two CCs, where two CCs are configured by the upper layer, and where in the UE (201) detects at least one DL concession for the transmission of data on a secondary CC, SCC; or the UE (201) adapts to change to the CA with large payload size, CA-L format, where the UE (201) supports up to five CCs, where more than one CC is configured by the upper layer, and in where the UE (201) detects at least one DL concession for the transmission of data on a secondary CC, SCC; or 5 10 fifteen twenty 25 30 35 40 Four. Five the UE (201) adapts to change to a simple CC, of non-CA format in the backward mode, where the UE (201) supports more than one CC, where more than one CCs is configured by the upper layer, and wherein the UE (201) only detects a DL concession for the transmission of data on PCC. 3. A method comprising: transmitting an upper layer configuration message of an eNB (502) to a user equipment, UE, (501) in a multi-carrier wireless communication network with carrier aggregation, CA; transmit one or more downlink concessions, DL; determine a HARQ feedback format based on the UE capacity of the maximum number of CCs supported by the transmitted DL concessions, and the upper layer configuration; Y receive and decode HARQ feedback information using the determined HARQ feedback format, characterized in that, depending on the number of CCs required to be supported by the UE (501), the eNB (502) uses a simple CC, a non-CA format to decode the HARQ feedback information for a non-CA capable UE; or the eNB (502) uses a simple CC, a non-CA format to decode the HARQ feedback information for an AC capable UE, where the eNB (502) configures only one CC for the upper layer; or The eNB (502) uses CA with small payload size, a CA-S format to decode the HARQ feedback information, where the UE (501) supports up to two CCs, and where two CCs are configured by the upper layer ; or the eNB (502) uses CA with large payload size, CA-L format to decode the HARQ feedback information, where the UE (501) supports up to five CCs, and where more than one CC is configured by the top layer; or The eNB (502) uses a simple CC, non-CA format to decode HARQ feedback information in backward mode for an AC capable UE, where more than one CCs is configured by the upper layer. 4. A base station (202), comprising: a radio resource control layer module (237), RRC, adapted to transmit a higher layer configuration message to a user equipment (201), UE, in a multi-carrier wireless communication network with carrier aggregation, CA ; a module (241) of physical layer, PHY, or module (240) of media access control layer, MAC, adapted to transmit one or more downlink concessions, DL, wherein the module (241) of PHY layer or the MAC layer module (240) are adapted to determine a HARQ feedback format based on the UE capacity of the maximum number of CCs supported, the DL concessions transmitted, and the configuration of the upper layer; Y an antenna (230) adapted to receive HARQ feedback information, wherein the HARQ feedback information is decoded using the determined HARQ feedback format, characterized in that, depending on the number of CCs required to be supported by the UE (201), the eNB (202) is adapted to use a simple CC, a non-CA format to decode the HARQ feedback information for the non-CA capable UE; or the eNB (202) is adapted to use a simple CC, a non-CA format to decode the HARQ feedback information for an AC capable UE, where the eNB (202) configures only one CC for the upper layer; or The eNB (202) is adapted to use the CA with small payload size, a CA-S format to decode the HARQ feedback information, where the UE (201) supports up to two CCs, and where two CCs are configured by the top layer; or The eNB (202) is adapted to use the CA with large payload size, a CA-L format to decode the HARQ feedback information, where the UE (201) supports up to five CCs, and where more than one CC it is configured by the upper layer; or The eNB (202) is adapted to use a simple CC, a non-CA format to decode the HARQ feedback information in backward mode for the AC capable UE, where more than one CCs is configured by the upper layer.