CN106559187A

CN106559187A - The feedback and method of reseptance of HARQ-ACK information and equipment

Info

Publication number: CN106559187A
Application number: CN201510621999.6A
Authority: CN
Inventors: 王轶; 张世昌; 付景兴; 李迎阳
Original assignee: Beijing Samsung Telecommunications Technology Research Co Ltd; Samsung Electronics Co Ltd
Current assignee: Beijing Samsung Telecommunications Technology Research Co Ltd; Samsung Electronics Co Ltd
Priority date: 2015-09-25
Filing date: 2015-09-25
Publication date: 2017-04-05
Anticipated expiration: 2035-09-25
Also published as: CN106559187B

Abstract

Present applicant proposes a kind of feedback method of HARQ-ACK information, according to the method that the application is provided, base station sends DL Assignment in the corresponding time-frequency binding window of sub-frame of uplink that corresponding HARQ-ACK feeds back.DL DAI are included in DL Assignment.UE in time-frequency binding window receives the DL-Assignment of dispatching downlink HARQ transmission, obtains the DL DAI in DL-Assignment, and determine the mapping value of each DL DAI；Then, the mapping value according to corresponding DL DAI, by the corresponding bits of the HARQ-ACK bit maps of each HARQ feedback unit to feedback bits sequence.Disclosed herein as well is a kind of DL-Assignment generates the feedback device of equipment and HARQ-ACK information.Using method and apparatus disclosed in the present application, can support in same descending sub frame, there are the HARQ-ACK feedbacks of multiple carrier waves for starting from different time points and sending downlink data, invalid HARQ-ACK bits are removed effectively, the efficiency of HARQ-ACK feedbacks is improved, so that it is guaranteed that the downlink peak rates of UE.

Description

HARQ-ACK information feedback and receiving method and device

Technical Field

The invention relates to a wireless communication system technology, in particular to a method and equipment for feeding back and receiving HARQ-ACK information.

Background

In an enhanced LTE (LTE-a) system, a plurality of Component Carriers (CCs) are aggregated by a Carrier Aggregation (CA) technique to obtain a larger working bandwidth, so that a data transmission rate can be further increased. Each CC corresponds to a Cell (Cell), and according to the current LTE standard (Rel-12), the UE can simultaneously operate on 5 CCs at most, one of which is a Primary CC (Pcell, Primary Cell), and the other CCs are called Secondary CCs (Scell, Secondary Cell).

In downlink communication of an LTE-a system, reliability of downlink data reception is ensured by a hybrid automatic Repeat reQuest (HARQ) technology. The UE receives a downlink grant (DL-Assignment), where the DL-Assignment is carried by a Physical Downlink Control Channel (PDCCH) or an Enhanced Physical Downlink Control Channel (EPDCCH), receives a Physical Downlink Shared Channel (PDSCH) according to indication information in the DL-Assignment, and for each Transport Block (TB) in the received PDSCH or a received Physical Downlink Control Channel (PDCCH) indicating Semi-Persistent Scheduling (SPS) release (hereinafter, both of which are collectively referred to as downlink HARQ transmission), the UE needs to feed back an ACK (correctly received) bit or a NACK (incorrectly received or lost) bit, hereinafter, collectively referred to as HARQ-ACK bit, to the base station through a corresponding uplink subframe. If the eNB receives the NACK bit, the transmission block corresponding to the NACK or the PDCCH indicating the SPS release is retransmitted. According to different HARQ-ACK feedback mechanisms, the LTE-A standard defines a corresponding method for determining the number of HARQ-ACK bits needing to be fed back and the corresponding HARQ-ACK bit value.

In the FDD system, if the UE feeds back HARQ-ACK bits through a Physical Uplink Shared Channel (PUSCH) on a certain uplink subframe n, the number of HARQ-ACK bits to be fed back is determined by the number of carriers configured by the UE and a transmission mode (a transmission mode of one TB or a transmission mode of two TBs) on each carrier. For each carrier configured by the UE, if the transmission mode is one TB, the carrier corresponds to one HARQ-ACK bit, and if the transmission mode is two TBs, the carrier corresponds to two HARQ-ACK bits. The bits are arranged in ascending order of carrier index to form a HARQ-ACK bit sequence finally fed back by the UE in the uplink subframe n (the HARQ-ACK bit sequence refers to the HARQ-ACK bit sequence before channel coding, the same applies below). It can be seen that in the HARQ-ACK feedback mechanism defined by the existing standard, the HARQ-ACK sequence finally fed back by the UE is determined by the configured number of carriers and transmission mode, and therefore the finally fed-back HARQ-ACK may include HARQ-ACK bits corresponding to carriers where there is no downlink HARQ transmission. When the maximum number of the carriers supported by the UE is 5, the existence of the invalid HARQ-ACK bit does not bring obvious influence on the performance of the system. But when the maximum number of carriers supportable by the UE increases further, for example, to 32, the negative impact of the invalid HARQ-ACK bit problem will certainly increase. In the research of 3GPP Rel-13eCA, the problem is discussed, and it is proposed that HARQ-ACK feedback is only based on actual scheduling, that is, only HARQ-ACK bits corresponding to carriers with downlink HARQ transmission are fed back. In order to avoid the inconsistency between the understanding of the base station and the UE about the number of feedback HARQ-ACK bits, for example, the base station schedules downlink HARQ transmissions of N downlink carriers, and the UE detects downlink HARQ transmissions of only M (M < N) downlink carriers, and 3GPP is studying DAI counting for all downlink carriers scheduled. That is, the DAIs are sorted in order from small to large, i.e., ascending, according to the index number of the scheduled carrier. As shown in fig. 1, the base station configures 16 carriers for the UE, and schedules 5 carriers, CC2, CC3, CC5, CC7, and CC15, in subframe n. The DAI included in the DCI scheduling the 5-carrier transmission is 0 to 4, respectively.

It should be noted that, in fig. 1, it is assumed that the aggregated carriers are all licensed band carriers. The scheduled carriers in the same subframe are all transmitted from the subframe edge, i.e. the #0OFDM symbol of the subframe at the same time. With the increasing shortage of spectrum resources, 3GPP is beginning to research data transmission on unlicensed Band (unlicensed Band) carriers. The LTE equipment can work on carriers of the authorized frequency band and the unauthorized frequency band at the same time and adopts a carrier aggregation or dual connection mode. One obvious difference between the unlicensed frequency band carrier and the licensed frequency band carrier is that signal transmission of the LTE device on the unlicensed frequency band carrier needs to be based on lbt (listen before talk), that is, the LTE device needs to monitor a busy-idle state of the unlicensed frequency band carrier, and if and only if the unlicensed frequency band carrier is idle, the LTE device can transmit a signal on the carrier. Since the LTE device cannot accurately predict when the unlicensed band carrier is idle, the LTE device may have uncertainty in transmitting on the unlicensed band carrier, that is, cannot determine in advance whether it can transmit in subframe n. Meanwhile, in order to improve the transmission efficiency of the LTE device on the unlicensed band carrier, the transmission of the LTE device on the unlicensed band carrier is allowed to start from the middle of a subframe, for example, the transmission of the PDSCH may start from a subframe boundary, i.e., #0 th OFDM symbol, or may start from a slot boundary, i.e., #0 th or #7 th OFDM symbol, or may start from more OFDM symbol boundaries, e.g., #0, #4, #7, #11OFDM symbols. Then, in the same subframe, when the LTE device transmits on multiple carriers, the transmission time start points of the respective carriers may be different. For example, the start of transmission time of the licensed band carrier is #0OFDM symbols of the subframe boundary, the start of transmission time of a part of the unlicensed band carrier is also #0OFDM symbols of the subframe boundary, and the start of transmission time of another part of the unlicensed band carrier is the second slot, i.e., #7OFDM symbols of the subframe. As shown in fig. 2, the base station configures 16 carriers for the UE, and in subframe n, the base station expects to schedule 9 carriers, which are CC2, CC3, CC5, CC7, CC8, CC9, CC11, CC14, and CC15, respectively. Wherein, the transmission of the licensed band carrier can be predetermined and can be started from the #0OFDM symbol, and the transmission of the unlicensed carrier is determined according to the LBT condition. In fig. 2, CC11 and CC15 complete LBT before subframe n, and thus transmission at subframe n may be determined before subframe n and it is determined to start transmission from #0OFDM symbol. And CC7 and CC9 do not complete LBT before subframe n and continue LBT in subframe n until LBT is completed before the second slot of subframe n, and thus it is determined in subframe n that it can transmit within subframe n and it is determined to start transmitting from #7OFDM symbol. And CC8 and CC14 fail to complete LBT before the second slot and thus cannot transmit in subframe n. Correspondingly, the bit preparation time of DCI containing DAI in each carrier is also before or after, and the transmission time of DCI is also divided from #0OFDM symbol and #7OFDM symbol. Therefore, if the DAIs are numbered from small to large in the order of the carrier indexes, the number of the DAI cannot be determined for the carrier with a smaller carrier index number but a relatively later downlink transmission time and the carrier with a larger carrier index number but a relatively earlier downlink transmission time. For example, CC11 and CC15 in fig. 2 have carrier indexes larger than CC7, CC8 and CC9, but when generating the DAI numbers of CC11 and CC15, since the base station cannot determine whether the carriers CC7, CC8 and CC9 can be transmitted in the same subframe, it cannot determine whether the DAI numbers need to be reserved for the three carriers. There is still no ideal solution to this problem.

In addition, 3GPP is also studying another type of DAI, indicating the total number of all downlink transmissions scheduled in the current subframe. And all DCIs of all downlink carriers scheduled by the current subframe comprise the DAI. When all the carriers are authorized frequency band carriers, the transmission is scheduled to be determined and started at the same time because all the carriers are transmitted in the current subframe. However, when the aggregated carriers include unlicensed band carriers, because whether the unlicensed band carriers can be accurately predicted before the current subframe when the current subframe is transmitted or not, for the DCI which starts to be transmitted at the #0 th OFDM symbol at the edge of the subframe, the DAI included therein is the total number of downlink carriers that cannot be accurately reflected in the scheduling of the subframe. As shown in fig. 2, DAI in DCI of CC2, CC3, CC5, CC11 and CC15 which starts to be transmitted at #0 th OFDM symbol at the boundary of subframe n cannot count all carriers transmitted in subframe n, i.e., cannot count whether CC7, CC8, CC9 and CC14 can be transmitted in the second slot of subframe n. There is also no ideal solution to this problem.

In a TDD system, the above problems also exist.

In addition, with the emergence of new services, the requirements on the time delay of wireless transmission are higher and higher. The existing 1ms subframe length as a minimum transmission time unit (TTI) cannot meet the requirement of time delay. Therefore, smaller TTIs, e.g. 0.5ms per subframe or as small as 1OFDM symbol 66.7us, will be included in the study content of 3 GPP. Then, when some of the multiple carriers still use 1ms TTI, and some of the carriers use smaller TTI and can start to transmit from the middle of 1ms subframe, the existing DAI indication cannot be applied.

Disclosure of Invention

The application provides a method and equipment for feeding back and receiving HARQ-ACK information, which can improve the efficiency of feeding back and receiving HARQ-ACK information and ensure the downlink peak rate of UE.

In order to achieve the purpose, the following technical scheme is adopted in the application:

a feedback method of hybrid automatic repeat request (HARQ-ACK) information comprises the following steps:

receiving a physical downlink control channel PDCCH or an enhanced physical downlink control channel EPDCCH (physical downlink control channel) transmitted by each downlink HARQ in a time-frequency binding window corresponding to an uplink subframe of a feedback HARQ-ACK (hybrid automatic repeat request-acknowledgement), acquiring a first type downlink scheduling downlink Assignment index (DL DAI) corresponding to the downlink HARQ in downlink authorization (DL-Assignment), and determining a mapping value of each first type DL DAI; wherein, the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window;

detecting HARQ feedback units in each downlink HARQ transmission in the time-frequency binding window, and determining corresponding HARQ-ACK bits;

and mapping the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window to the corresponding bit of the feedback bit sequence according to the mapping value of the first type of DL DAI.

Preferably, the time-frequency bundling window includes time units where all downlink HARQ transmissions of the HARQ-ACK fed back in the uplink subframe are located, and the time units where all downlink HARQ transmissions are located are ordered according to a set rule; and in the time-frequency binding window, the starting point of each time unit corresponds to the starting point of the HARQ feedback unit sent in the time unit.

Preferably, the time unit includes N OFDM symbols, lengths of different time units in the same time-frequency bundling window are the same or different, and N is a set positive integer.

Preferably, when the time-frequency bundling window only includes one downlink subframe, any time unit included in the time-frequency bundling window is: the L1 th OFDM symbol in the downlink subframe is used as a time resource of which the starting point and the last OFDM symbol are used as the ending point; wherein, the time units are arranged according to the sequence of the time unit starting points, and L1 is a set positive integer.

Preferably, when the time-frequency bundling window only includes one downlink subframe,

the mapping value of the first DL DAI of any downlink HARQ transmission within the time-frequency bundling window is used to represent: the total number of HARQ feedback units sent by the base station from the 1 st time unit to the time unit where any downlink HARQ transmission is located in the downlink subframe to the carrier where any HARQ feedback unit downlink HARQ transmission is located from the first carrier; or,

the mapping value of the first DL DAI of any downlink HARQ transmission within the time-frequency bundling window is used to represent: and in the time unit of any downlink HARQ transmission, the total number of the HARQ feedback units sent by the base station is from the first carrier to the carrier of any downlink HARQ transmission.

Preferably, when the time-frequency bundling window includes a plurality of downlink subframes, any time unit included in the time-frequency bundling window is: in a downlink subframe of the plurality of downlink subframes, taking the L2 th OFDM symbol as a starting point and taking the last OFDM symbol as an end point; wherein, each time unit is arranged according to the sequence of the downlink subframe where the time unit is located, and for different time units on the same downlink subframe, the time units are arranged according to the sequence of the starting points of the time units, and L2 is a set positive integer.

Preferably, when the time-frequency bundling window includes a plurality of downlink subframes,

the mapping value of the first DL DAI of any downlink HARQ transmission within the time-frequency bundling window is used to represent: the total number of HARQ feedback units sent by the base station from the 1 st time unit to the time unit of any downlink HARQ transmission, from the 1 st carrier to the carrier of any downlink HARQ transmission, from the first downlink subframe of the time-frequency binding window to the downlink subframe of any downlink HARQ transmission, in all downlink subframes in the time-frequency binding window; or,

continuously taking values of the first class DL DAI of the same time unit on each downlink subframe in the time-frequency binding window; or,

the first class DL DAI value of any downlink HARQ transmission in the time-frequency bundling window includes a subframe dimension DAI value and a carrier dimension DAI value, wherein the subframe dimension DAI value is determined according to the existing manner, and the carrier dimension DAI value is used to represent: and in the downlink subframe carrying any downlink HARQ transmission, the total number of HARQ feedback units sent by the base station is from the first time unit of the downlink subframe to the time unit of any downlink HARQ transmission, and from the first carrier to the carrier of any downlink HARQ transmission.

Preferably, when the configured transmission starting positions of the downlink HARQ transmissions of all the unlicensed carriers are the same, the first class DAI of the downlink HARQ transmission of the licensed band carrier is lower than the first class DAI of the downlink HARQ transmission of the unlicensed carrier.

Preferably, when the first type of DAI value is not subjected to modulo operation, the starting point sequence of each downlink HARQ transmission in the time-frequency binding window is consistent with the ascending sequence of the corresponding DAI value.

Preferably, the HARQ feedback unit is a downlink subframe, a downlink time unit, or a transport block TB where downlink HARQ transmission exists.

Preferably, after receiving the PDCCH or EPDCCH, acquiring a second DL DAI corresponding to the downlink HARQ transmission in DL-Assignment, and determining a mapping value thereof;

and further performing mapping according to the mapping value of the second type DL DAI when the HARQ-ACK bit of each HARQ feedback unit is mapped.

Preferably, when the time-frequency bundling window only includes one downlink subframe, the mapping value of the second type DL DAI of any downlink HARQ transmission in the time-frequency bundling window is used to indicate: and starting from the starting point of the time-frequency binding window until the time unit of any downlink HARQ transmission or the time unit of the DL-Assignment, and counting the HARQ feedback units sent by the base station on all carriers.

Preferably, when the time-frequency bundling window includes a plurality of downlink subframes, the mapping value of the second type DL DAI of any downlink HARQ transmission in the time-frequency bundling window is used to represent: the total number of HARQ feedback units sent by the base station on all carriers from the 1 st time unit to the time unit where any downlink HARQ transmission is located, and from the first downlink subframe of the time-frequency binding window to the downlink subframe where any downlink HARQ transmission is located, in all downlink subframes in the time-frequency binding window; or,

the second class DL DAI value of any downlink HARQ transmission in the time-frequency bundling window includes a subframe dimension second class DAI value and a carrier dimension second class DAI value, wherein the subframe dimension second class DAI value is determined according to the existing manner, and the carrier dimension second class DAI value is used to represent: and in the downlink subframe carrying any downlink HARQ transmission, the total number of the HARQ feedback units sent by the base station on all carriers from the 1 st time unit to the time unit where any downlink HARQ transmission is located.

Preferably, the mapping value of DL DAI of the second type for any downlink HARQ transmission in the time-frequency bundling window is used to indicate: starting from the starting point of the time-frequency binding window to the end point of the time-frequency binding window, or starting from the starting point of the time-frequency binding window to the last time unit of the subframe where any downlink HARQ transmission is located in the time-frequency binding window, the total number of HARQ feedback units expected to be sent by the base station on all carriers, or the total number of HARQ feedback units actually sent.

Preferably, the total number of HARQ feedback units sent by the base station is less than or equal to the mapping value of the second type DL DAI of the downlink HARQ transmission before the current time, and the UE performs HARQ-ACK bit feedback according to the mapping value of the second type DL DAI of the downlink HARQ transmission; or the total number of the HARQ feedback units actually sent by the base station is larger than the mapping value of the second type DL DAI of the downlink HARQ transmission before the current time, the base station updates the mapping value of the second type DL DAI corresponding to the current downlink HARQ transmission, and the UE carries out the feedback of the HARQ-ACK bits according to the updated mapping value of the second type DL DAI.

Preferably, the mapping value of DL DAI of the second type for any downlink HARQ transmission in the time-frequency bundling window is used to indicate: the HARQ feedback units in any downlink HARQ transmission are the last X HARQ feedback units on all carriers from the start of the time-frequency bundling window to the time unit in which any downlink HARQ transmission or DL Assignment is located, where X is a set positive integer and corresponds to different mapping values of the second type of DL DAI, and the values of X are the same or different.

Preferably, the mapping value of DL DAI of the second type for any downlink HARQ transmission in the time-frequency bundling window is used to indicate: the HARQ feedback units in any downlink HARQ transmission are the last Y HARQ feedback units expected to be sent by the base station on all carriers from the start point of the time-frequency bundling window to the time unit where any downlink HARQ transmission or DL Assignment is located, Y is a set positive integer and corresponds to different mapping values of the second class of DL DAI, and the values of Y are the same or different.

A method for receiving HARQ-ACK information, comprising:

sending a PDCCH or an EPDCCH for scheduling each downlink HARQ transmission in a time-frequency binding window corresponding to an uplink subframe for feeding back the HARQ-ACK, and carrying a first type of DL DAI corresponding to the downlink HARQ transmission in DL-Assignment carried by the PDCCH or the EPDCCH; wherein, the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window;

sending HARQ feedback units in each downlink HARQ transmission in a time-frequency binding window;

and receiving a feedback bit sequence, and correspondingly extracting the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window according to the mapping value of the first type of DL DAI.

the mapping value of the first DL DAI of any downlink HARQ transmission within the time-frequency bundling window is used to represent: the total number of HARQ feedback units sent by the base station from the first carrier to the carrier where any downlink HARQ transmission is located in the time unit where any downlink HARQ transmission is located;

the time-frequency binding window comprises time units where all downlink HARQ transmissions of the HARQ-ACK are fed back in the uplink subframe; in the time-frequency binding window, the starting point of each time unit corresponds to the starting point of the HARQ feedback unit sent in the time unit, and the time units are arranged according to the sequence of the starting points of the time units.

the first class DL DAI value of any downlink HARQ transmission in the time-frequency bundling window includes a subframe dimension DAI value and a carrier dimension DAI value, wherein the subframe dimension DAI value is determined according to the existing manner, and the carrier dimension DAI value is used to represent: in a downlink subframe carrying any downlink HARQ transmission, the total number of HARQ feedback units sent by a base station is counted from a first time unit of the downlink subframe to a time unit where the downlink HARQ transmission is located, from a first carrier to a carrier where the downlink HARQ transmission is located;

the time-frequency binding window comprises time units where all downlink HARQ transmissions of the HARQ-ACK are fed back in the uplink subframe; in the time-frequency binding window, the starting point of each time unit corresponds to the starting point of the HARQ feedback unit sent in the time unit, the time units are arranged according to the sequence of the downlink subframe in which the time unit is positioned, and different time units on the same downlink subframe are arranged according to the sequence of the starting points of the time units.

Preferably, the DL-Assignment carries a second type DL DAI corresponding to the downlink HARQ transmission;

and further performing mapping value according to the second type DL DAI when the HARQ-ACK bit is extracted.

the mapping value of the second DL DAI of any downlink HARQ transmission within the time-frequency bundling window is used to represent: the total number of HARQ feedback units sent by the base station on all carriers from the 1 st time unit to the time unit where any downlink HARQ transmission is located, and from the first downlink subframe of the time-frequency binding window to the downlink subframe where any downlink HARQ transmission is located, in all downlink subframes in the time-frequency binding window; or,

Preferably, the mapping value of DL DAI of the second type for any downlink HARQ transmission in the time-frequency bundling window is used to indicate:

the HARQ feedback units in any downlink HARQ transmission are the last X HARQ feedback units on all carriers from the starting point of the time-frequency binding window to the time unit where any downlink HARQ transmission or DL Assignment is located, wherein X is a set positive integer and corresponds to different mapping values of a second type of DL DAI, and the values of X are the same or different; or,

the mapping value of the second type DL DAI of any downlink HARQ transmission within the time-frequency bundling window is used to represent: the HARQ feedback units in any downlink HARQ transmission are the last Y HARQ feedback units expected to be sent by the base station on all carriers from the start point of the time-frequency bundling window to the time unit where any downlink HARQ transmission or DL Assignment is located, Y is a set positive integer and corresponds to different mapping values of the second class of DL DAI, and the values of Y are the same or different.

A feedback apparatus of HARQ-ACK information, comprising: the device comprises a receiving unit, a detecting unit and a feedback unit;

the receiving unit is configured to receive a PDCCH or an EPDCCH for scheduling each downlink HARQ transmission in a time-frequency bundling window corresponding to an uplink subframe for feeding back HARQ-ACK, obtain first DL DAIs corresponding to the downlink HARQ transmission in DL-Assignment, and determine a mapping value of each first DL DAI; wherein, the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window;

the detection unit is used for detecting the HARQ feedback unit in each downlink HARQ transmission in the time-frequency binding window and determining the corresponding HARQ-ACK bit;

and the feedback unit is used for mapping the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window to the corresponding bit of the feedback bit sequence according to the mapping value of the first type of DL DAI.

A receiving apparatus of HARQ-ACK information, comprising: a transmitting unit and a receiving unit;

the sending unit is used for sending PDCCH or EPDCCH for scheduling each downlink HARQ transmission in the time-frequency binding window corresponding to the uplink subframe for feeding back the HARQ-ACK, and carrying the first type DL DAI corresponding to the downlink HARQ transmission in DL-Assignment; wherein, the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window; the HARQ feedback unit is also used for sending the HARQ feedback units in each downlink HARQ transmission in the time-frequency binding window;

and the receiving unit is used for receiving the feedback bit sequence and correspondingly extracting the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window according to the mapping value of the first class of DL DAI.

According to the technical scheme, in the time-frequency binding window corresponding to the uplink subframe for feeding back the HARQ-ACK, the PDCCH or EPDCCH transmitted by each downlink HARQ in the time-frequency binding window is received and scheduled, the first type DL DAI corresponding to the downlink HARQ transmission in the DL-Assignment is obtained, and the mapping value of each first type DL DAI is determined. And detecting the HARQ feedback units in each downlink HARQ transmission in the time-frequency binding window, and determining corresponding HARQ-ACK bits. And mapping the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window to the corresponding bit of the feedback bit sequence according to the mapping value of the first type of DL DAI. In the above processing, the mapping value of the first type DL DAI is determined according to the starting position of the corresponding downlink HARQ transmission in the time-frequency bundling window. Therefore, the number of the scheduled downlink carriers at each current time can be correctly reflected according to the DL DAI, the HARQ-ACK feedback and receiving efficiency is improved, and the downlink peak rate of the UE is ensured.

Drawings

Fig. 1 is a schematic diagram of a scheduled carrier transmission start position when aggregation carriers are both authorized frequency band carriers;

fig. 2 is a schematic diagram of a scheduled carrier transmission start position when part of an aggregation carrier is an authorized frequency band carrier and part of the aggregation carrier is an unauthorized frequency band carrier;

fig. 3a and 3b are schematic diagrams of time-frequency bundling windows in the case that the downlink CC is an FDD carrier;

fig. 4 is a schematic diagram of a time-frequency bundling window in the case that a downlink CC is a TDD carrier;

FIG. 5 is a schematic diagram of a first preferred type DL DAI of the present application 1;

FIG. 6 is a schematic diagram of a preferred first type DL DAI of the present application, FIG. 2;

FIG. 7 is a diagram of a preferred first type DL DAI of the present application, schematically illustrated in FIG. 3;

FIG. 8 is a diagram of a preferred first type DL DAI of the present application, schematically illustrated in FIG. 4;

FIG. 9 is a diagram of a preferred first type DL DAI of the present application, schematically illustrated in FIG. 5;

FIG. 10 is a diagram of a preferred first type DL DAI of the present application, schematically illustrated in FIG. 6;

FIG. 11 is a schematic diagram of a preferred first type DL DAI and second type DL DAI of the present application 1;

FIG. 12 is a schematic diagram of a preferred first type DL DAI and second type DL DAI of the present application 2;

FIG. 13 is a schematic illustration of a preferred first type DL DAI and second type DL DAI of the present application 3;

FIG. 14 is a schematic illustration of a preferred first type DL DAI and second type DL DAI of the present application 4;

FIG. 15 is a schematic illustration of a preferred first type DL DAI and second type DL DAI of the present application 5;

FIG. 16 is a diagram of a preferred first type DL DAI and second type DL DAI of the present application shown in FIG. 6;

fig. 17 is a schematic diagram 7of a preferred first type DL DAI and second type DL DAI of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and examples.

In the current research of downlink HARQ transmission, DL DAIs included in DL Assignment sequence DL DAIs corresponding to downlink HARQ transmission according to the index number of the scheduled carrier. With the occurrence of partial subframes (partial subframes) of the unlicensed carriers and the occurrence of shorter TTIs supporting smaller time delays, different transmission starting positions of PDCCH/EPDCCH/PDSCH of different carriers may occur in the same subframe, that is, different transmission starting positions of downlink HARQ may occur, so that the DL DAI determined in the above manner cannot accurately reflect the number of scheduled downlink carriers, and thus the UE cannot perform accurate HARQ-ACK feedback and reception according to the DL DAI.

Based on the analysis, the method provides a new HARQ-ACK feedback and receiving scheme, and the method is carried out according to the starting position of downlink HARQ transmission when corresponding DL DAI is set for the downlink HARQ transmission, so that the quantity of the downlink carriers scheduled at each current time can be correctly reflected according to the DL DAI, the accuracy and the efficiency of HARQ-ACK feedback and receiving are improved, the downlink peak rate of UE is ensured, and the system performance is improved.

The scheme provided by the application comprises two aspects: the method for feeding back the HARQ-ACK information by the UE and the method for receiving the HARQ-ACK information by the base station.

Specifically, the feedback method of the HARQ-ACK information at the UE side includes:

step a, receiving PDCCH or EPDCCH transmitted by each downlink HARQ in a scheduling time-frequency binding window in a time-frequency binding window corresponding to an uplink subframe for feeding back HARQ-ACK, acquiring first type DL DAI corresponding to the downlink HARQ transmission in DL-Assignment, and determining a mapping value of each first type DL DAI; the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window;

step b, detecting HARQ feedback units in each downlink HARQ transmission in a time-frequency binding window, and determining corresponding HARQ-ACK bits;

and c, mapping the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window to the corresponding bit of the feedback bit sequence according to the mapping value of the first type of DL DAI.

The method for receiving the HARQ-ACK information of the base station side comprises the following steps:

a1, sending PDCCH or EPDCCH for scheduling each downlink HARQ transmission in a time-frequency binding window corresponding to an uplink subframe for feeding back HARQ-ACK, and carrying a first type DL DAI corresponding to the downlink HARQ transmission in DL-Assignment carried by the PDCCH or the EPDCCH; the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window;

step b1, sending HARQ feedback units in each downlink HARQ transmission in the time-frequency binding window;

and c1, receiving the feedback bit sequence, and correspondingly extracting the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window according to the mapping value of the first type of DL DAI.

By the HARQ feedback and receiving method, the DL DAI can be suitable for PDSCH/PDCCH/EPDCCH transmission smaller than a subframe, and the total number of HARQ feedback units until the DL assignment is received in a time-frequency binding window can be accurately reflected, so that the HARQ feedback and receiving accuracy can be improved, and the system performance can be improved. The following describes the above-mentioned specific implementation of the present application in detail by two embodiments. Wherein, the HARQ feedback and receiving method is corresponding, and there are repeated parts in the specific process, and for the sake of clarity of the description, the following will be described from the perspective of UE process, and for the special process in which the base station needs to perform, it will be described together in the process.

The first embodiment is as follows:

the present embodiment provides a method for feeding back HARQ-ACK information, which is used in a downlink multi-carrier transmission system, such as a CA system or a DC (dual connectivity) system, and is characterized in that the method includes:

step 101: the UE receives DL-Assignment of scheduling downlink HARQ transmission in a time-frequency binding window corresponding to an uplink subframe of the feedback HARQ-ACK, acquires first-class DL DAIs in the DL-Assignment and determines a mapping value of each first-class DL DAI;

step 102: UE detects HARQ feedback units in each downlink HARQ transmission in a time-frequency binding window and determines corresponding HARQ-ACK bits;

step 103: the UE determines the total length O of the feedback bit sequence fed back on the subframe n according to the detected DAI_ACK。

Step 104: and the UE maps the HARQ-ACK bit of each HARQ feedback unit to the corresponding bit of the feedback bit sequence according to the mapping value of the corresponding first type DL DAI. And reporting the feedback bit sequence to the base station.

The HARQ feedback unit refers to an entity corresponding to each HARQ-ACK bit fed back by the UE. In the present application, the HARQ feedback unit may be a downlink subframe or a downlink time unit or a Transport Block (TB). Specifically, the method comprises the following steps:

if the HARQ feedback unit is a downlink subframe, each downlink subframe with downlink HARQ transmission may generate one HARQ-ACK bit (hereinafter, referred to as HARQ-ACK bit of the subframe) corresponding to the feedback bit sequence, if the transmission mode of the downlink subframe is one TB, the one bit is the HARQ-ACK bit corresponding to the TB transmitted in the subframe, otherwise, if the transmission mode of the downlink subframe is two TBs, the one bit is the result of spatial bundling of the two HARQ-ACK bits corresponding to the two TBs transmitted in the subframe.

If the HARQ feedback unit is a downlink time unit, each downlink time unit with downlink HARQ transmission may generate one HARQ-ACK bit (hereinafter, referred to as a HARQ-ACK bit of the time unit) corresponding to the feedback bit sequence, if the transmission mode of the downlink time unit is one TB, the one bit is the HARQ-ACK bit corresponding to the TB transmitted in the time unit, otherwise, if the transmission mode of the downlink time unit is two TBs, the one bit is a result after spatial bundling of the two HARQ-ACK bits corresponding to the two TBs transmitted in the time unit.

If the HARQ feedback unit is a TB, the HARQ-ACK bit of each TB corresponds to one bit in the feedback bit sequence fed back. For a subframe or time unit with downlink HARQ transmission in one of the carriers with a TB transmission mode, a bit corresponds to the feedback bit sequence, whereas for a subframe or time unit with downlink HARQ transmission in one of the carriers with two TB transmission modes, two bits correspond to the feedback bit sequence.

The UE determines the type of the HARQ feedback unit by receiving the signaling of the eNB, wherein the signaling comprises at least one of the following signaling forms: broadcast messages, RRC layer signaling, MAC layer signaling, physical layer signaling.

Preferably, the time-frequency bundling window includes time units where all downlink HARQ transmissions requiring HARQ-ACK feedback in the uplink subframe n are located, and all time units are ordered according to a set rule.

Preferably, the time unit is N OFDM symbols, and the length N of each time unit may be different. The following describes the definition of the time unit in the time-frequency bonding window in detail with respect to the number of downlink subframes included in the time-frequency bonding window.

(1) When the time-frequency binding window only contains one downlink subframe, the time-frequency binding window contains M₁A time unit of M₁Each time unit corresponds to the L-th time unit in the downlink sub-frame₁，L₂，…L_MOne OFDM symbol is a starting point, and the last Z OFDM symbols of the downlink subframe are time resources of an ending point, preferably, Z is 1. That is, the time units are arranged according to the sequence of the starting points of the time units, and the earlier the starting point is, the earlier the time units are arranged in the time-frequency binding window. For example, as shown in FIG. 3a, M₁2, the first time unit corresponds to a time resource from a start point of a1 st OFDM symbol in a downlink subframe to an end point of a last OFDM symbol of the downlink subframe, that is, a subframe; the second time unit corresponds to a time resource from the 8 th OFDM symbol in the downlink subframe, i.e. the #7OFDM symbol, as a starting point to the last OFDM symbol in the downlink subframe as an ending point, i.e. a time slot. For another example, as shown in FIG. 3b, M₁4, the first time unit corresponds to a time resource from the 1 st OFDM symbol in the downlink subframe, that is, the #0OFDM symbol as a starting point to the last OFDM symbol of the downlink subframe as an end point, that is, a subframe; the second time unit corresponds to a time resource from the beginning of the 5 th OFDM symbol in the downlink subframe, namely the #4OFDM symbol, to the end of the last OFDM symbol in the downlink subframe, namely 10 OFDM symbols; the third time unit corresponds to the 8 th OFDM symbol in the downlink subframe, namely the #7OFDM symbol is taken as the starting point to the last of the downlink subframeA time resource with one OFDM symbol as an end point, that is, one time slot; the fourth time unit corresponds to a time resource from the 12 th OFDM symbol in the downlink subframe, that is, the #11OFDM symbol, as a starting point to the last OFDM symbol in the downlink subframe as an ending point, that is, 3 OFDM symbols. The two examples given above are given only as examples, and the present invention is also applicable to the case of dividing the downlink subframe into smaller time units in the time dimension with other granularities. For convenience of explanation, the following description refers to M only₁As an example, the starting positions of the two time units are the start of the subframe and the start of the second slot, respectively.

(2) When the time-frequency binding window only contains a plurality of subframes, assume N₁When each downlink subframe is occupied, the time-frequency binding window contains M₂A time unit, any time unit corresponding to the N₁An L-th OFDM symbol in a downlink subframe of a subframe is a time resource from a starting point to a last Z OFDM symbols of the downlink subframe, preferably Z ═ 1, which is an ending point, for example, M is a time resource of the downlink subframe₂Each time unit corresponds to the following time resources: in the first downlink sub-frame, the L < th > frame₁，L₂，…L_MThe time resource with one OFDM symbol as the starting point and the last OFDM symbol as the ending point in the first downlink sub-frame and the L-th downlink sub-frame₁，L₂，…L_MTime resource with one OFDM symbol as starting point and the last OFDM symbol as end point of the second downlink sub-frame, …, Nth₁In each downlink subframe, the L-th subframe₁，L₂，…L_MStarting from one OFDM symbol, Nth₁And the last OFDM symbol of each downlink subframe is the time resource of the terminal point. That is, each time unit is arranged according to the sequence of the downlink subframe where the time unit is located, different time units on the same downlink subframe are arranged according to the sequence of the starting point of the time unit, the earlier the time unit of the located downlink subframe is, the earlier the sequence in the time-frequency binding window is, the earlier the different time units on the same downlink subframe are, the earlier the starting point is, the earlier the time unit is, the earlier the sequence in the time-frequency binding window is, and the earlier the sequence in the time-frequency binding window is.

Preferably, the DAI value of the downlink HARQ transmission corresponding to each time unit in the time-frequency bundling window may be determined in the following manner:

(1) and when the time-frequency binding window only comprises one downlink subframe, the base station sends DL-Assignment of a scheduling carrier c, wherein the contained first type DL DAI is used for indicating the total number of HARQ feedback units sent by the base station from the first carrier to the carrier c scheduled by the DL-Assignment in the downlink subframe from the 1 st time unit until the downlink HARQ transmission scheduled by the DL-Assignment or the k time unit where the DL-Assignment is located. The first carrier is a carrier having the smallest DAI value, and the carrier index and DAI value are associated with each other according to a predefined rule. For example, the ascending or descending order of carrier indices corresponds to the ascending order of DAIs. Value m of said first type of DAI_DAI1,c,kThis can be implemented by the following pseudo code:

setting m_DAI1＝0

Setting i to 1

Setting j to 1

while i<＝M₁

while j<＝Nc

The sub-frame number is n-k on if carrier j_cThe subframe is a downlink subframe, HARQ-ACK bits of the subframe are fed back in an uplink subframe n, and the sequence number of the subframe of the base station is n-k_cStarts to transmit the PDCCH/EPDCCH of the scheduled PDSCH in the ith downlink time unit in the subframe,

j is a carrier index where a time unit in the time-frequency binding window is located, and j is more than 0 and less than or equal to Nc;

nc is the total number of downlink component carriers for feeding back HARQ-ACK in the uplink subframe;

the subframe number of the downlink subframe in the time-frequency binding window is n-k_cWherein n is the subframe number of the uplink subframe, k_cFor a predefined value, e.g. k_c＝4。

i is the downlink subframe n-k_cThe time unit index in the index table satisfies that i is more than 0 and less than or equal to M₁。

It should be noted that, in general, on the same carrier, if PDCCH/EPDCCH is transmitted in the downlink subframe, only M is used₁One of the starting points starts transmission without occurrence of a plurality of PDCCH/EPDCCH whose transmission starting points are different. Moreover, on the unlicensed frequency band carrier, for a downlink transmission burst (dl transmission burst), only in the first subframe, the starting point position of the PDCCH/EPDCCH may be M₁One of the starting points, in the subsequent subframe of the current downlink transmission burst, the starting point position of the PDCCH/EPDCCH is fixed and uniquely determined, or the time unit in which the starting point position of the PDCCH/EPDCCH is fixed.

When the UE finds the downlink subframe n-k in the time-frequency binding window_cFor example, assuming that the UE starts from the beginning of the first time unit to the current time unit k, and the total number of detected PDSCHs and PDCCH/EPDCCH indicating downlink SPS release is U from the first carrier to the carrier c_DAIThe value of the first type DAI in the received DL-Assignment DCI satisfies m_DAI1,≠(U_DAI-1) mod4+1, the UE can find at least one DL-Assignment missed. In the feedback bit sequence of the UE, a bit corresponding to the HARQ feedback unit corresponding to the PDSCH scheduled by the missed PDCCH/EPDCCH is NACK.

A more detailed example is given in fig. 5. The base station configures 8 carriers for the UE, wherein the CC 1-CC 3 are authorized carriers, and the CC 4-CC 8 are unauthorized carriers. The base station is in the downlink subframe n-k in the time-frequency binding window_cIt is desirable to schedule 7 carriers for downlink transmission, CC 2-CC 8. AuthorizationAnd carriers CC2 and CC3, starting transmission in the first time unit of the subframe, i.e., the subframe start position. The sending of the unlicensed carrier is determined according to the result of the LBT carrier detection. Wherein, CC4 fails to pass carrier monitoring, and therefore cannot occupy the channel in the subframe, and CC5, CC6 occupy the channel and transmit the HARQ feedback unit in the second slot. CC8 fails to occupy the channel by carrier monitoring, while CC7 occupies the channel and starts sending HARQ feedback elements at the beginning of the subframe. Therefore, when the base station transmits the DAI, the base station first performs DAI numbering of the first type on the carriers which start to be transmitted in the first time unit according to the carrier index in ascending order, that is, CC2DAI is 1, CC3DAI is 2, and CC7DAI is 3. Then, for the carrier starting to transmit in the second time unit, the first-class DAI numbering is performed according to the carrier index in ascending order, namely CC5DAI is 4 and CC6DAI is 5.

And the UE receives the DAI and maps the HARQ-ACK bit of each HARQ feedback unit to the corresponding bit of the feedback bit sequence according to the mapping value of the DL DAI. Therefore, if the UE receives the DAIs on the 5 carriers, the UE determines the total length of the feedback ACK/NACK bits according to the DAI on the CC with the highest carrier index received in the second time slot, i.e., the DAI value on the CC 6. Assuming that these 5 carriers are all transmission modes supporting only one TB transmission, the total length of ACK/NACK bits is 5. And the UE sorts the corresponding ACK/NACK according to the sequence of the DAIs 1-5. If the UE receives only a partial DAI, for example:

(a) if the UE receives only DAIs 1,2, 4, 5 of CC2, CC3, CC5, CC6, the UE, when detecting DAI 4, U_DAI＝3，m_DAI1,UE discovery m 4_DAI1,≠(U_DAI-1) mod4+1, it can be determined that a DAI was missed by the detection. The UE still determines that the total length of the feedback ACK/NACK bits is 5 bits according to the DAI on the CC with the highest carrier index received in the second slot, i.e., the DAI value on the CC 6. The UE sorts the ACK/NACK bits corresponding to the DAI1, 2, 4, 5 and the NACK without detecting the DAI 3 in the order of the DAIs. Assuming that the PDSCH of CC2, CC3, CC5, and CC6 are all demodulated correctly, the ACK bit generated by the UE is ACK ACKNACK ACK ACK. Although the UE cannot judge the missed detection DWhether the HARQ feedback unit corresponding to AI 3 starts to transmit from the first slot or the second slot does not affect the determination of the position of the corresponding NACK in the fed-back ACK sequence.

(b) If the UE receives only DAIs 1, 3, 5 of CC2, CC7, CC6, the UE may determine that two DAIs have been missed. The UE still determines that the total length of the feedback ACK/NACK bits is 5 bits according to the DAI on the CC with the highest carrier index received in the second slot, i.e., the DAI value on the CC 6. The UE sorts the ACK/NACK bits corresponding to the DAIs 1, 3, 5 and the NACK for the undetected DAIs 2, 4 in the order of the DAIs. Assuming that the PDSCH of CC2, CC7, and CC6 are all demodulated correctly, the ACK bit generated by the UE is ACK NACKACK NACK ACK. The UE may determine, through DAI1 and DAI 3 detected in the first slot, that the PDSCH corresponding to the missed DAI2 is sent from the first slot, but the UE cannot determine whether the PDSCH corresponding to the missed DAI 4 is sent from the first slot or the second slot, but does not influence it to determine the position of the corresponding NACK in the fed-back ACK sequence.

(2) When the time-frequency binding window comprises a plurality of downlink subframes, the base station sends a first type DAI of a scheduling carrier c to indicate that the first downlink subframe (namely the downlink subframe n-k) in the time-frequency binding window is from the 1 st time unit to the kth time unit, from the first carrier to the carrier c and from the first downlink subframe (namely the downlink subframe n-k) in the time-frequency binding window in all downlink subframes in the time-frequency binding window_max,c) Up to downlink sub-frame n-k_cAnd the total number of the HARQ feedback units sent by the base station. k is a radical of_c∈K_c，K_cAnd the UE feeds back the HARQ-ACK adopted by the downlink subframe on the carrier c on the uplink subframe n to determine the HARQ timing relationship. Value m of the DAI_{DAI1,c,k,n-kc}It can be determined in two ways as shown by the following pseudo code:

the first method is as follows: the first class of DAIs is counted jointly in subframe and carrier dimensions:

setting m_DAI1＝0

Setting l to k_max,c

Setting i to 1

Setting j to 1

while l>＝k_min,c

while i<＝M₁

while j<＝Nc

On if carrier j, the subframe with the subframe number of n-l is a downlink subframe, HARQ-ACK bits of the subframe are fed back in the uplink subframe n, and the base station starts to send PDCCH/EPDCCH for scheduling PDSCH on the ith downlink time unit in the subframe with the subframe number of n-l,

k_min,cIs the last downlink subframe in the time-frequency binding window.

A more detailed example is given in fig. 6. The base station configures 8 carriers for the UE, wherein the CC 1-CC 3 are authorized carriers, and the CC 4-CC 8 are unauthorized carriers. The time-frequency binding window comprises 2 downlink subframes, namely a subframe 1 and a subframe 2. The base station expects to schedule 7 carriers for downlink transmission in subframe 1, CC 2-CC 8. The licensed carriers CC2 and CC3 start transmitting at the first time unit of the subframe, i.e., the subframe start position. The sending of the unlicensed carrier is determined according to the result of the LBT carrier detection. Wherein, the CC4 fails to pass carrier monitoring, and thus cannot occupy the channel in the subframe, and the CC5 and the CC6 occupy the channel and transmit the PDSCH/PDCCH/EPDCCH in the second time slot. CC8 fails to occupy the channel due to not being monitored by the carrier, while CC7 occupies the channel and starts sending HARQ feedback units at the beginning of the subframe. The base station expects to schedule 7 carriers for downlink transmission in subframe 2, CC1, CC 3-CC 8. The licensed carriers CC1 and CC3 start transmitting at the first time unit of subframe 2, i.e., the subframe start position. The sending of the unlicensed carrier is determined according to the result of the LBT carrier detection. Wherein, the CC8 fails to pass carrier monitoring, and thus cannot occupy the channel in the subframe, and the CC4 occupies the channel and transmits the PDSCH/PDCCH/EPDCCH in the second time slot. The unlicensed band carriers CC 5-CC 7 occupy the channel in subframe 1, so LBT is not needed in subframe 2, and the transmission can be directly performed, and starts from the first time unit of subframe 2. Therefore, when transmitting DAI, the base station first performs DAI numbering of the first type on the carriers starting to be transmitted in the first time unit of the subframe 1 according to the carrier index in ascending order, that is, CC2DAI is 1, CC3DAI is 2, and CC7DAI is 3. Then, the carriers starting to be transmitted in the second time unit of the subframe 1 are numbered with the first DAI according to the carrier index in ascending order, i.e., CC5DAI is 4 and CC6DAI is 5. Subsequently, for the carrier that starts to be transmitted in the first time unit of the subframe 2, the first class DAI numbering is performed according to the carrier index in ascending order, that is, CC1 DAI is 6, CC3DAI is 7, CC5DAI is 8, CC6DAI is 9, and CC7DAI is 10. And then, for the carrier which starts to be transmitted in the second time unit of the subframe 2, the first-type DAI numbering is performed according to the carrier index, namely, CC4 DAI is 11.

And the UE receives the DAI and maps the HARQ-ACK bit of each HARQ feedback unit to the corresponding bit of the feedback bit sequence according to the mapping value of the DL DAI. Therefore, if the UE receives all the DAIs, the UE determines the total length of the feedback ACK/NACK bits according to the DAI on the CC with the highest carrier index received in the second slot of the second subframe, i.e., the DAI value on the CC 4. Assuming that all carriers are in a transmission mode supporting only two TB transmissions, the total length of ACK/NACK bits is 2 × DAI value 2 × 11 — 22. It is assumed here that the HARQ feedback unit is a time unit, not a TB. And then the UE sorts the corresponding ACK/NACK according to the sequence of the DAIs 1-11. If the UE receives only a partial DAI, for example:

(a) if the UE receives only CC2, CC5, CC6 of subframe 1, DAI1, 4, 5, 3 of CC7, CC1, CC6 of subframe 2, DAI 6, 9, 11of CC 4. Then the UE may determine that one DAI2 is missed in the first slot of the subframe 1, and 3 DAIs, DAIs 7, DAIs 8, and DAIs 10 are missed in the subframe 2, where the DAIs 7 and 8 may determine that the missed DAI 10 is missed in the first slot of the subframe 2, but the UE cannot determine that the missed DAI 10 is in the second slot of the subframe, but does not affect the UE to determine the location to map the corresponding NACK. The UE still determines that the total length of the feedback ACK/NACK bits is 22 bits according to the DAI value on the CC4 with the highest carrier index received in the second slot of the second subframe. And the UE sorts the ACK/NACK bits according to ascending DAI indexes by the ACK/NACK corresponding to the detected DAI and the NACK not detected by the DAI.

(b) If the UE receives only the DAIs 1, 4, 3 of CC2, CC5, CC 7of subframe 1, CC3, CC4, CC6 of subframe 2, DAI 7, 11, 9, 10 of CC 7. Then the UE may determine that one DAI2 was missed in the first slot of subframe 1, 1 DAI 8 was missed in the first slot of subframe 2, and 2 DAIs, DAIs 5 and DAIs 6 were missed in the second slot of subframe 1 or the first slot of subframe 2. Although the UE cannot determine that the two DAIs are in the second slot of subframe 1 or the first slot of subframe 2, it does not affect the UE to determine the NACK positions corresponding to the two DAIs. The UE still determines that the total length of the feedback ACK/NACK bits is 22 bits according to the DAI value on the CC4 with the highest carrier index received in the second slot of the second subframe. And the UE sorts the ACK/NACK bits according to ascending DAI indexes by the ACK/NACK corresponding to the detected DAI and the NACK not detected by the DAI.

The second method comprises the following steps: the first class of DAIs is counted in the subframe dimension and the carrier dimension, i.e., two independent DAIs correspond to the subframe dimension and the carrier dimension, respectively. The DAI of the subframe dimension may be according to methods in the existing standards, e.g. 7.3.2.1 in TS 36.213. The DAI of the carrier dimension, the base station and the UE count according to the method of (1) in this embodiment when the time-frequency bundling window only includes one downlink subframe.

In another implementation manner of this embodiment, the values of the first type of DAI may be counted in each time unit. For example, for the time-frequency bundling window in (1) containing only one downlink subframe, it is assumed that the downlink subframe contains M₁2 time units, the entire subframe and the second slot. Then, in the current time unit k, the first type DAI m in the DL-Assignment DCI of carrier c_DAI1,Indicating the number of HARQ feedback units accumulated from the first carrier up to carrier c in the current time unit k in the downlink subframe. Then, the UE maps the HARQ-ACK bit of each HARQ feedback unit to the corresponding bit of the feedback bit sequence according to the received mapping value of the DL DAI and the sequence of the time units. When the time-frequency binding window in (2) contains a plurality of downlink subframes, the first class DAIm in the DL-Assignment DCI of the same time unit of the plurality of subframes can be used_DAI1,And continuously taking values, for example, when the time-frequency binding window includes 2 downlink subframes, continuously numbering the DAIs of the first slot of the subframe 1 and the subframe 2, and continuously numbering the DAIs of the second slot of the subframe 1 and the subframe 2, but numbering the DAIs of the first slot and the second slot respectively.

As shown in fig. 7, it is assumed that (1) the time-frequency bundling window only includes one downlink subframe. The DAIs of CC2, CC3, and CC7 starting to be transmitted in the first slot are DAI1, 2, and 3, respectively, and the DAIs of CC5 and CC6 starting to be transmitted in the second slot are DAI1 and DAI2, respectively. And the UE sorts the fed back ACK/NACK according to the DAI respectively received by the two slots and the sequence of the slots from small to large, namely, the ACK/NACK is fed back according to the sequence of CC2, CC3, CC7, CC5 and CC 6.

Preferably, a simplified example of this embodiment: if the possible sending starting positions of the HARQ feedback units of all the unauthorized carriers configured for the UE are certain the same, the base station can configure the authorized frequency band carrier to correspond to a lower carrier index number and the unauthorized frequency band carrier to correspond to a higher carrier index number, and the first class DAI and the carrier index numbers are in one-to-one correspondence according to the ascending relationship. In this case, the DAI may be numbered only according to the order of the carrier index numbers and/or the order of the subframes within the time bundling window without dividing the subframes into smaller time units. For example, due to the influence of adjacent channel leakage or avoiding excessive wifi resource preemption, all unlicensed band carriers configured for the UE may be limited to transmit at the same time, that is, all unlicensed band carriers may transmit signals only from the same time point, for example, from the subframe edge or the second timeslot. Since the licensed band carrier always starts transmission from the subframe edge, the unlicensed band carrier cannot start transmission at an earlier time point in the same subframe than the licensed band carrier. Therefore, the uncertainty problem that the carriers sent in the same subframe later are numbered first can be avoided by firstly carrying out DAI numbering on the carriers in the authorized frequency range and then carrying out DAI numbering on the carriers in the unauthorized frequency range. As shown in fig. 8, CC 1-CC 3 are licensed band carriers, and CC 4-CC 8 are unlicensed band carriers of the same band. CC 4-CC 8 can only start transmission or not transmit at the same time. CC4 and CC8 fail to occupy the channel and cannot transmit in the subframe. The CC 5-CC 7 complete carrier monitoring after the subframe edge and before the second slot, and although the time for completing eCCA is different, the three CCs need to align the transmission time and start transmission together at the second slot. Then, DAI numbering is carried out on the CCs successfully sending signals in the sub-frame according to the ascending order of the carrier indexes, and the numbers are respectively DAI 1-5.

Preferably, the modulo operation may be performed according to the first type of DAI determined by the above method. For example, if the number of bits indicating the first type of DAI is 2 bits, the bits indicating the first type of DAI take values modulo 4 the value of the first type of DAI, e.g., the value of the bits indicating the first type of DAI in DCI ═ m (m)_DAI1-1) mod4+ 1. Then figure 5The values of DAI are shown in fig. 9.

It should be noted that, if the number of bits used for the first-type DAI indication in the DL Assignment is sufficient to directly indicate the value of the DAI without modulo, the method described above may not limit that the DAI needs to be sorted according to the order of the carrier indexes, but only limit that the DAI needs to be sorted in an ascending order according to the order of the starting points of the HARQ feedback units to be transmitted. Then, for example, when the time-frequency bundling window in (1) only includes one downlink subframe, the UE assumes the first type DAI m received in the current time unit_DAI1,Indicating the downlink sub-frame n-k within the time-frequency bundling window_cStarting from the beginning of the first time unit, and accumulating the number of HARQ feedback units from a certain carrier corresponding to a smaller DAI to the carrier c until the current time unit k. As shown in fig. 10, the DAI index value of the second slot is still after the DAI index value of the first slot, but the 2 DAIs of the second slot, i.e. the DAI values of CC5 and CC6, may not be arranged in an ascending order according to the carrier index, but may be arranged in an inverted order, where the DAI of CC5 is 6 and the DAI of CC6 is 4. The UE only needs to sort the corresponding ACK/NACK according to the sequence of the DAI values from small to large.

The above examples are all described by taking the feedback unit as the time unit. Preferably, when the feedback unit is TB, the above method of the present embodiment is also applicable to DAI counting in TB units. That is, if the TM configured for the carrier j supports transmission of 2 TBs and spatial bundling (spatial bundling) is not configured, the DAI corresponding to the carrier is a value obtained by adding 2 to the DAI corresponding to the previous carrier. For example, when the time-frequency bundling window only includes one downlink subframe, the first type of DAI for transmitting the scheduling carrier c is used to indicate the total number of TBs transmitted by the base station from the 1 st time unit to the kth time unit, and from the first carrier to the carrier c in the downlink subframe (the number of TBs is 1 for PDCCH/EPDCCH releasing SPS). Value m of the DAI_DAI1,c,kThis can be determined in the following manner:

setting m_DAI1＝0

Setting i to 1

Setting j to 1

while i<＝M₁

while j<＝Nc

it is assumed that the first type of DAI received in step 101 is determined based on any of the above manners. That is, the UE assumes a first type of DAI m received at the current time unit_DAI1,Indicating the downlink sub-frame n-k within the time-frequency bundling window_cStarting from the beginning of the first time unit, and up to the current time unit k, and the total number of accumulated HARQ feedback units from the first carrier up to the carrier c. Then, in step 103, the UE determines the total length O of the feedback bit sequence according to the value of the last first class DAI of the last time unit detected in the time-frequency bundling window_ACK. Finally, in step 104, the UE maps the HARQ-ACK bits of each HARQ feedback unit to corresponding bits of the feedback bit sequence according to the received mapping value of the DL DAI. For the feedback bit sequence, the bit corresponding to no feedback unit, i.e. no corresponding DAI is detected, should be set as NACK.

It is noted that, due to the PDSCH of SPS, the transmission of PDSCH of SPS is not scheduled by PDCCH/EPDCCH, except that SPS activation or SPS deactivation involves PDCCH/EPDCCH scheduling. Also, usually, the transmission of PDSCH of SPS is known in advance, for example, starting at the first slot of the SPS resource subframe. Therefore, the present embodiment does not discuss the case when there is SPS PDSCH transmission in the method of determining how to determine DAI when the PDSCH transmission starting position is uncertain. However, when feeding back the ACK/NACK bit, the UE needs to feed back not only PDCCH/EPDCCH scheduled PDSCH and SPS release PDCCH/EPDCCHHARQ-ACK information, but also HARQ-ACK information of SPS PDSCH. The mapping of HARQ-ACK of PDSCH of SPS may be according to the prior art, or may adopt other new technical solutions, and the present invention is not limited. For example, if SPS downlink transmission exists in the time-frequency bundling window, HARQ-ACK bits corresponding to the SPS downlink transmission are mapped to a set position of the feedback bit sequence. Preferably, the HARQ-ACK bit corresponding to the SPS transmission is mapped to the beginning of the feedback bit sequence in an ascending order according to the index of the downlink subframe in the time-frequency binding window, or is mapped to the front of the HARQ-ACK bit corresponding to the downlink HARQ transmission scheduled by the DL-Assignment containing the type I; or the HARQ-ACK bit corresponding to the SPS transmission is mapped to the tail of the feedback bit sequence in a descending order according to the index of the downlink subframe in which the SPS transmission is positioned in the time-frequency binding window, or is mapped to the front of the HARQ-ACK bit corresponding to the downlink HARQ transmission scheduled by the DL-Assignment containing the type I.

It should be noted that the first type of DAI in this embodiment cannot completely avoid the inconsistency between the UE and the base station in understanding the total number of scheduled PDCCH/EPDCCH. For example, if the UE misses one PDCCH/EPDCCH or N PDCCH/EPDCCH with the largest first-type DAI value, the UE cannot determine the missing by only depending on the detected first-type DAI. For example, in fig. 5, if the UE detects only CC2, CC3, CC7 and CC5, but does not detect CC6, the DAI received by the UE is continuous, DAI1, 2,3, 4. The UE cannot find DAI 5 missing CC 6. Therefore, the UE feeds back only ACK/NACKs of 4 carriers, but the base station expects to receive ACK/NACKs of 5 carriers. The base station can determine the ACK/NACK fed back by the UE by blindly detecting the ACK/NACK of 5 carriers and the ACK/NACK feedback sequence of 4 carriers. Alternatively, the UE may determine whether to miss detection according to other DAI indication information, for example, the second type of DAI in embodiment two, by indicating the number of HARQ feedback units sent by the base station within the time-frequency bundling window, or by indicating the number of the last one or more HARQ feedback units sent by the base station within the time-frequency bundling window, in combination with the first type of DAI. The first embodiment may be used in combination with an existing or other new technical solution for solving the problem that the UE fails to detect one or more HARQ feedback units with the largest DAI value, and will not be described in detail herein.

Example two:

in this embodiment, on the basis of the first embodiment, the DL-Assignment further includes a second type DL DAI, and when performing HARQ-ACK bit mapping, the value of the second type DL DAI is further considered. Specifically, the feedback method for HARQ-ACK information provided in this embodiment is used in a downlink multi-carrier transmission system, for example, a CA system or a DC (dual connectivity) system, and the method specifically includes:

step 201: the UE receives DL-Assignment of scheduling downlink HARQ transmission in a time-frequency binding window corresponding to an uplink subframe of the feedback HARQ-ACK, acquires a first class DAI and a second class DAI in the DL-Assignment, and determines a mapping value of each DL DAI;

step 202: the UE detects the HARQ feedback units in each downlink HARQ transmission in the time-frequency binding window and determines corresponding HARQ-ACK bits;

step 203: the UE determines the total length O of the feedback bit sequence fed back on the subframe n according to the second type and/or the first type DAI_ACK。

Step 204: and the UE maps the HARQ-ACK bit of each HARQ feedback unit to the corresponding bit of the feedback bit sequence according to the mapping value of the corresponding DL DAI. And reporting the feedback bit sequence to the base station.

The method for using the first type of DAI in this embodiment is the same as that in the first embodiment, and will not be described herein again. The present embodiment is mainly described with respect to DAI of the second type.

Preferably, the first class of DAI and the second class of DAI correspond to different bit fields in the same DL Assignment.

Preferably, the first class of DAI and the second class of DAI correspond to the same bit field in the same DL Assignment. The DAI of the second type is used only under predetermined conditions.

Preferably, the first type of DAI and the second type of DAI are in different DCIs. For example, a first type of DAI is in PDCCH/EPDCCH scheduling PDSCH and a second type of DAI is in DCI dedicated to indicate PDCCH/EPDCCH. Preferably, the second type of DAI indicates the total number of the PDCCH/EPDCCH for scheduling PDSCH and the PDCCH/EPDCCH for indicating SPS release sent by the base station from the beginning of the time-frequency bundling window until the kth time unit where the PDSCH scheduled by the DL-Assignment or the DL-Assignment is located. The definition of the time unit is the same as that of the first embodiment.

(1) And when the time-frequency binding window only comprises one downlink subframe, the base station sends the DL-Assignment of the scheduling carrier c, wherein the contained second-type DAI is used for indicating the total number of HARQ feedback units sent by the base station on all carriers from the 1 st time unit to the kth time unit where the downlink HARQ transmission scheduled by the DL-Assignment or the DL-Assignment is located in the downlink subframe. Value m of the DAI_DAI2,kThis can be determined by means of the following pseudo code:

setting m_DAI2＝0

Setting i to 1

Setting j to 1

while i<＝M₁

while j<＝Nc

The sub-frame number is n-k on if carrier j_cThe subframe is a downlink subframe, HARQ-ACK bits of the subframe are fed back in an uplink subframe n, and the sequence number of the subframe of the base station is n-k_cStarts to transmit PDCCH/EPDCCH of the scheduled PDSCH in the ith downlink time unit in the subframe (taking PDSCH as downlink HARQ transmission as an example),

It can be seen that the DAI of the second type generated by the method, the DAI of the second type transmitted in the time unit before the time, does not include the number of PDCCH/EPDCCH transmitted in the time unit after the time. As shown in fig. 11, the second type DAI in the first slot is 3, which indicates that the total number of PDCCH/EPDCCH transmitted on all carriers in the first slot is 3, and the second type DAI in the second slot is 5, which indicates that the total number of HARQ feedback units transmitted on all carriers from the first slot to the second slot is 5, that is, the total number of transmission starting points of downlink HARQ transmission is the first slot and the starting point is the second slot is 5. If the UE misses CC6 in the second slot, the UE may compare the total number U of detected HARQ feedback units counted by the UE_DAI4 and a second class of DAIm_DAI2Determining that one HARQ feedback unit is missed, 5.

(2) When the time-frequency binding window comprises a plurality of downlink subframes, the base station sends DL-Assignment of a scheduling carrier c, wherein the contained second type DAI is used for indicating that in all the downlink subframes in the time-frequency binding window, from the 1 st time unit to the kth time unit where downlink HARQ transmission scheduled by the DL-Assignment or the DL-Assignment is located, from the first downlink subframe n-k in the time-frequency binding window_maxUntil the downlink HARQ transmission scheduled by the DL-Assignment or the downlink subframe where the DL-Assignment is locatedn-k_cThe total number of HARQ feedback units transmitted by the base station on all carriers. k is a radical of_c∈ Kc, K is determined by the HARQ timing relationship used by the UE to feed back the HARQ-ACK of the downlink subframe on carrier c on uplink subframe n_DAI2,k,n-kcIt can be determined in the following two ways:

the first method is as follows: the DAI of the second type is counted jointly in the subframe dimension and the carrier dimension:

setting m_DAI2＝0

Setting l to k_max

Setting i to 1

Setting j to 1

while l>＝k_min,c

while i<＝M₁

while j<＝Nc

It can be seen that the DAI of the second type generated by the method, the DAI of the second type transmitted in the time unit before the time, does not include the number of HARQ feedback units transmitted in the time unit after the time or in the time unit in the subframe after the time in the same subframe. As shown in fig. 12, there are 2 subframes in the time-frequency bundling window. The second class DAI of CC2, CC3, and CC 7of the first slot in subframe 1 is 3, the second class DAI of CC5 and CC6 of the second slot in subframe 1 is 5, the second class DAI of CC1, CC3, CC8, CC9, and CC10 of the first slot in subframe 2 is 10, and the second class DAI of CC 4of the second slot in subframe 2 is 11.

The second method comprises the following steps: the DAIs of the second type are counted in the subframe dimension and the carrier dimension, respectively. I.e. two independent DAIs correspond to the subframe dimension and the carrier dimension, respectively. The DAI of the subframe dimension may be according to the method in the existing standard, for example, the method of 7.3.2.1 in TS 36.213 or other new technical solutions. The DAI of the carrier dimension, the base station and the UE count according to the method of (1) in this embodiment when the time-frequency bundling window only includes one downlink subframe.

In step 203, the UE determines the total length O of the feedback bit sequence fed back on the subframe n according to the first and second types of DAIs of PDCCH/EPDCCH in the last time unit detected by the UE in the time-frequency bundling window_ACK. If the total number of HARQ feedback units calculated based on the first type of DAI is smaller than the value indicated by the second type of DAI, the UE determines the total length O of the feedback bit sequence according to the value indicated by the second type of DAI_ACK. For example, in fig. 12, if the UE detects the CC5 of the second slot but does not detect the HARQ feedback units in the downlink HARQ transmission of the CC6 of the second slot, the UE may find that the total number of HARQ feedback units indicated by the second type DAI in the CC5 is 5, and the total number of HARQ feedback units indicated by the first type DAI is 4. The UE may determine that one is missed and the UE determines that the total length of the feedback bit sequence is 5 based on 5 of the second type DAI.

In step 204, the UE determines the timingAnd in the frequency binding window, determining the bit position of the fed-back bit sequence by the first class DAI and the second class DAI of the downlink HARQ transmission in each time unit detected by the UE. Suppose the feedback bit sequence is o₀o₁,...,And sequentially discharging the ACK/NACK according to the sequence of the first type DAI detected by the UE from small to large. For the bits in the feedback bit sequence corresponding to the non-feedback unit, NACK should be set, i.e. 0. For example, in fig. 11, if the UE detects the CC5 of the second slot but does not detect the PDCCH/EPDCCH of the CC6 of the second slot, the UE may find that the total number of HARQ feedback units indicated by the second type of DAI in the CC5 is 5, and the total number of HARQ feedback units indicated by the first type of DAI is 4. The UE may determine that one is missed and the UE determines that the total length of the feedback bit sequence is 5 based on 5 of the second type DAI. Assuming that the UE detects PDCCH/EPDCCH for CC2, CC3, CC5, CC7 and the scheduled PDSCH are all demodulated correctly, the UE generates ACK/NACK feedback bit sequence ACK ACK ACK ACK NACK. The last NACK is the feedback corresponding to the missed HARQ feedback unit with the first type DAI of 5.

Preferably, the DAI of the second type indicates an upper limit of the total number of HARQ feedback units expected to be transmitted and/or actually transmitted by the base station from the start point of the time-frequency bundling window to the end point of the time-frequency bundling window. It can also be interpreted that the DAI of the second type indicates the total number of HARQ feedback units assumed by the UE to feed back the ACK/NACK sequence from the start of the time-frequency bundling window to the end of the time-frequency bundling window. The values of the second class of DAIs sent in each time unit of the time-frequency bundling window are the same, or the values of the second class of DAIs sent in each time unit of the time-frequency bundling window may be different. The definition of the time unit is the same as that of the first embodiment. Or, the second class DAI of the current downlink HARQ transmission may further indicate: starting from the starting point of the time-frequency binding window until the last time unit of the subframe where the current downlink HARQ transmission is located in the time-frequency binding window, the total number of HARQ feedback units expected to be sent by the base station on all carriers or the total number of HARQ feedback units actually sent.

Since the base station may not accurately predict the carrier in the unlicensed frequency band, in a later time unit or a later subframe, whether the base station may occupy the channel to start sending the PDCCH/EPDCCH/PDSCH may be monitored by the carrier, and therefore, the second class of DAI sent in an earlier time unit is probably not equal to the total number of HARQ feedback units actually sent by the base station in the time-frequency bonding window. And when the total number of the HARQ feedback units which can be sent by the base station is larger than the second type of DAI sent by the earlier time unit, the base station can only send the total number of the HARQ feedback units which is equal to the second type of DAI in the time-frequency bundling window. When the total number of the HARQ feedback units which can be sent by the base station is less than the second type of DAI, the UE still determines the total bit number of the fed-back ACK/NACK according to the second type of DAI. Or, in another implementation manner, when the total number of HARQ feedback units that the base station can send is greater than the second class of DAIs sent by earlier time units, the base station may send the total number of HARQ feedback units that is equal to, less than, or greater than the second class of DAIs within the time-frequency bundling window, and update the second class of DAIs in the current time unit according to the number of actually sent HARQ feedback units in the current time unit. Here, the HARQ feedback unit that the base station can send means that the base station has a service that needs to be sent, and the base station also successfully occupies a carrier, and can perform downlink HARQ transmission on the carrier.

In the above method, when the time-frequency bundling window includes multiple subframes, for example, in a TDD system, the second type DAI may indicate the total number of all HARQ feedback units in one subframe, or may indicate the total number of all HARQ feedback units in all subframes in the time-frequency bundling window, or may indicate the total number of all HARQ feedback units starting from the start point of the time-frequency bundling window and ending at the last time unit of the subframe where the current downlink HARQ transmission is located in the time-frequency bundling window.

As shown in fig. 13, it is assumed that the time-frequency bundling window only includes one subframe. The DAI of the second type indicates an upper limit of the total number of HARQ feedback units expected to be transmitted and/or actually transmitted by the base station from the start point of the time-frequency bundling window to the end point of the time-frequency bundling window. And the values of the second class of DAIs sent in each time unit of the time-frequency binding window are the same. And when the total number of the HARQ feedback units which can be sent by the base station is larger than the second type of DAI sent by the earlier time unit, the base station can only send the total number of the HARQ feedback units which is equal to the second type of DAI in the time-frequency bundling window. Specifically, the DAI of the second type is 5, which indicates that the total number of HARQ feedback units that the base station predicts can be transmitted in two time units in the subframe is 5. It can be seen that the transmission of CC2, CC3, and CC7, CC8 is started from the first time unit, and the base station does not know whether CC4, CC5, and CC6 can occupy the channel to transmit signals in the second time unit. The base station estimates more conservatively that at least one of the three carriers may occupy the channel for transmitting signals during the second time unit. As a practical matter, CC4 may not occupy the channel, and both CC5 and CC6 may complete LBT before the second time unit and may signal. However, since the base station predicts that only one carrier can transmit signals, the base station can only transmit signals on one carrier, CC 5. Even though the base station may transmit two carriers.

As shown in fig. 14, it is assumed that the time-frequency bundling window includes two subframes. The second class of DAI indicates the total number of HARQ feedback units that the base station expects to send on all carriers from the start of the time-frequency bundling window until the last time unit of the subframe where the current downlink HARQ transmission is located within the time-frequency bundling window. When the total number of the HARQ feedback units that the base station can send is greater than the second class of DAIs sent by earlier time units, the base station can send the total number of the HARQ feedback units that is greater than the second class of DAIs within the time-frequency bundling window, and at the current time unit, the second class of DAIs is updated at the current time unit according to the number of the actually sent HARQ feedback units. Assuming that in the first subframe, the total number of HARQ feedback units expected by the base station to be transmitted in the first subframe is equal to the total number of actually transmitted HARQ feedback units, in the second subframe, the total number of HARQ feedback units expected by the base station to be transmitted in the second subframe in the first slot of the second subframe is smaller than the total number of HARQ feedback units transmitted by the base station in the second subframe, that is, the second type DAI transmitted in the first slot of the second subframe is 10 (5 in the first subframe + 5 in the first slot of the second subframe), but the base station transmits one more HARQ feedback unit in the second slot of the second subframe, so that the base station transmits the updated second type DAI in the second slot of the second subframe is 11. The UE determines the size of the feedback ACK/NACK sequence according to this second type of DAI.

Preferably, the second type of DAI indicates that downlink HARQ transmission scheduled by DL-Assignment including the second type of DAI starts from the start point of the time-frequency bundling window until the kth time unit where the downlink HARQ transmission scheduled by DL-Assignment or the DL-Assignment is located, and on all carriers, the PDCCH/EPDCCH for scheduling PDSCH and the last X PDCCH/EPDCCH for indicating SPS release are sent by the base station. The definition of the time unit is the same as that of the first embodiment.

Preferably, X is 1 or X is 1,2, 3.

Preferably, if the DAI of the second type is 1 bit, 0 indicates not the last HARQ feedback unit, and 1 indicates the last HARQ feedback unit, or vice versa.

Preferably, if the DAI of the second type is 2 bits, 0 indicates that the last HARQ feedback unit is not the 1 or 2 or 3, 1 indicates that the last HARQ feedback unit is the 3, 2 indicates that the last HARQ feedback unit is the 2, and 3 indicates that the last HARQ feedback unit is the 1, or vice versa. Or 1 means that there are 1 HARQ feedback units, 2 means that there are 2 HARQ feedback units, and 3 means that there are the last 3 HARQ feedback units. Or according to other predetermined rules, 1,2 or 3 HARQ feedback units are indicated to follow.

As shown in fig. 15, the DL-Assignment includes a first class DAI and a second class DAI, and the second class DAI takes a value of 0 or 1 by using an independent bit field. The time-frequency binding window only comprises one subframe. 1 represents that the PDCCH/EPDCCH carrying the DL-Assignment starts from the starting point of the time-frequency binding window, namely the first slot of the current subframe, until the PDSCH scheduled by the DL-Assignment or the kth time unit where the DL-Assignment is located, and on all carriers, the PDCCH/EPDCCH for scheduling the PDSCH and the last 1 PDCCH/EPDCCH for indicating the PDCCH/EPDCCH released by the SPS are sent by the base station. 0 means not the last one. In the first time unit, i.e. the first slot, the DAIs of the second type of CC2, CC3 and CC7 are 0,0 and 1, respectively, i.e. it means that CC7 starts from the first slot and the last PDCCH/EPDCCH. In the second time unit, i.e. the second slot, the DAIs of the second type of CC5 and CC6D are DAI 0,1, respectively, i.e. it means that CC6 is the last PDCCH/EPDCCH starting from the first slot and ending at the second slot.

Preferably, the second type of DAI indicates that the PDSCH scheduled by the DL-Assignment including the second type of DAI starts from the start point of the time-frequency bundling window until the kth time unit where the PDSCH scheduled by the DL-Assignment or the DL-Assignment is located, and on all carriers, the base station expects to send the last X HARQ feedback units. It can also be interpreted that the DAI of the second type indicates the total number of the last X HARQ feedback units assumed by the UE to feed back the ACK/NACK sequence from the start of the time-frequency bundling window to the end of the time-frequency bundling window. The definition of the time unit is the same as that of the first embodiment.

Taking a subframe/time unit with downlink HARQ transmission as an example of the HARQ feedback unit, if the PDCCH/EPDCCH actually sent by the base station in the later time unit exceeds the number indicated by the base station in the time unit before the time, the PDCCH/EPDCCH sent by the base station in the later time unit may be limited not to exceed the number indicated in the time unit before the time, or may exceed the number and the base station labels the DAI in the time unit after the time according to the actually sent PDCCH/EPDCCH. If the PDCCH/EPDCCH actually sent by the base station in the later time unit is smaller than the number indicated by the base station in the earlier time unit, the UE still needs to determine the size and the order of the ACK/NACK sequence fed back by the UE according to the number indicated by the base station in the earlier time unit, or the base station may mark the DAI in the later time unit according to the actually sent PDCCH/EPDCCH, and the UE determines the size and the order of the ACK/NACK sequence fed back by the UE according to the last received DAI.

As shown in fig. 16, the DL-GRANT includes a first class DAI and a second class DAI, and adopts independent bit fields, and the values of the second class DAI are 0,1,2, and 3. The time-frequency binding window only comprises one subframe. In the first time unit, i.e. the first slot, the DAIs of the second type of CC2, CC3, CC7 and CC8 are 0,0,0 and 3, respectively, i.e. it means that the base station predicts that there are 3 PDCCH/EPDCCH in the second slot. In the second time unit, i.e. the second slot, the base station fails to occupy the channels of 3 carriers, and only sends PDCCH/EPDCCH on CC5 and CC 6. However, in order to ensure that the total number of ACK/NACK corresponding to the second slot fed back by the UE is 3, the DAI of the second type indicated by the base station is 2,1, respectively, which means that there are 2 HARQ feedback units after CC5 and 1 HARQ feedback unit after CC 6. Therefore, the UE generates ACK/NACK according to CC2, CC3, CC7, CC8, CC5, and CC6, respectively, and adds one NACK at the end when generating the ACK/NACK bit.

As shown in fig. 17, the DL-Assignment includes a first class DAI and a second class DAI, and independent bit fields are adopted, and the values of the second class DAI are 0,1,2, and 3. The time-frequency binding window only comprises one subframe. In the first time unit, i.e. the first slot, the DAIs of the second type of CC2, CC3, CC7 and CC8 are 0,0,0 and 3, respectively, i.e. it means that the base station predicts that there are 3 PDCCH/EPDCCH in the second slot. In the second time unit, i.e. the second slot, the base station fails to occupy the channels of 3 carriers, and only sends PDCCH/EPDCCH on CC5 and CC 6. Then the DAIs of CC5 and CC6 generated by the base station are 1 and 0, respectively, indicating that there are 1 PDCCH/EPDCCH after CC5 and 0 PDCCH/EPDCCH after CC 6. Accordingly, the UE generates ACK/NACK according to CC2, CC3, CC7, CC8, CC5, and CC6, respectively, when generating the ACK/NACK bit.

Preferably, the modulo operation may be performed according to the DAI of the second type determined by the above method. For example, if the bit number indicating the second class of DAI is 2 bits, the bit indicating the second class of DAI is pairThe value of the second type of DAI is modulo 4, e.g., the value of the bit in DCI indicating the second type of DAI is (m ═ m)_DAI1-1)mod4+1。

Under the several determination modes of the second class DL DAIs given above, the last HARQ feedback units missed in the time-frequency bonding window can be found by combining the values of the first class DL DAI and the second class DL DAI.

It is noted that the method of the first or second embodiment is equally applicable to other forms of DAI.

The foregoing is a specific implementation of the HARQ feedback and receiving method in this application. The application also provides a concrete implementation of the HARQ feedback and receiving equipment.

The HARQ feedback device provided by the application comprises a receiving unit, a detecting unit and a feedback unit. The receiving unit is used for receiving and scheduling PDCCH or EPDCCH transmitted by each downlink HARQ in a time-frequency binding window corresponding to an uplink subframe for feeding back HARQ-ACK, acquiring first type DL DAIs corresponding to the downlink HARQ in DL-Assignment, and determining a mapping value of each first type DL DAI; wherein, the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window. And the detection unit is used for detecting the HARQ feedback unit in each downlink HARQ transmission in the time-frequency binding window and determining the corresponding HARQ-ACK bit. And the feedback unit is used for mapping the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window to the corresponding bit of the feedback bit sequence according to the mapping value of the first type of DL DAI.

The HARQ receiving device comprises a sending unit and a receiving unit. The sending unit is used for sending PDCCH or EPDCCH for scheduling each downlink HARQ transmission in a time-frequency binding window corresponding to an uplink subframe for feeding back HARQ-ACK, and carrying a first type of DL DAI corresponding to the downlink HARQ transmission in DL-Assignment; wherein, the mapping value of the first type DL DAI is determined according to the initial position of the corresponding downlink HARQ transmission in the time-frequency binding window; and the HARQ feedback unit is also used for sending the HARQ feedback units in each downlink HARQ transmission in the time-frequency binding window. And the receiving unit is used for receiving the feedback bit sequence and correspondingly extracting the HARQ-ACK bit of each HARQ feedback unit in the time-frequency binding window according to the mapping value of the first type of DL DAI.

It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.

In addition, functional units in the embodiments of the present application may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.

The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A feedback method of hybrid automatic repeat request HARQ-ACK information is characterized by comprising the following steps:

2. The method of claim 1, wherein the time-frequency bundling window comprises time units in which all downlink HARQ transmissions for feeding back HARQ-ACK in the uplink subframe are located, and the time units in which all downlink HARQ transmissions are located are ordered according to a set rule; and in the time-frequency binding window, the starting point of each time unit corresponds to the starting point of the HARQ feedback unit sent in the time unit.

3. The method of claim 2, wherein the time unit comprises N OFDM symbols, and lengths of different time units in a same time-frequency bundling window are the same or different, and N is a positive integer.

4. The method of claim 2, wherein when the time-frequency bundling window only includes one downlink subframe, any time unit included in the time-frequency bundling window is: the L1 th OFDM symbol in the downlink subframe is used as a time resource of which the starting point and the last OFDM symbol are used as the ending point; wherein, the time units are arranged according to the sequence of the time unit starting points, and L1 is a set positive integer.

5. The method of claim 4, wherein when the time-frequency bundling window comprises only one downlink subframe,

6. The method of claim 2, wherein when the time-frequency bundling window comprises a plurality of downlink subframes, any time unit included in the time-frequency bundling window is: in a downlink subframe of the plurality of downlink subframes, taking the L2 th OFDM symbol as a starting point and taking the last OFDM symbol as an end point; wherein, each time unit is arranged according to the sequence of the downlink subframe where the time unit is located, and for different time units on the same downlink subframe, the time units are arranged according to the sequence of the starting points of the time units, and L2 is a set positive integer.

7. The method of claim 6, wherein when the time-frequency bundling window comprises a plurality of downlink subframes,

8. The method as claimed in claim 4 or 6, wherein when the transmission starting positions of the configured downlink HARQ transmissions of all the unlicensed carriers are the same, the first type DAI of the downlink HARQ transmission of the licensed band carrier is lower than that of the downlink HARQ transmission of the unlicensed carriers.

9. The method of claim 1, wherein when the first type of DAI values do not perform the modulo operation, the starting point sequence of each downlink HARQ transmission in the time-frequency bundling window is consistent with the ascending sequence of the corresponding DAI values.

10. The method of claim 1, wherein the HARQ feedback unit is a downlink subframe, a downlink time unit or a Transport Block (TB) in which a downlink HARQ transmission exists.

11. The method according to claim 1,2,3, 4, 5, 6, 7, 9 or 10, wherein after receiving the PDCCH or EPDCCH, a second DL DAI corresponding to the downlink HARQ transmission in DL-Assignment is obtained and a mapping value thereof is determined;

12. The method of claim 11, wherein when the time-frequency bundling window only includes one downlink subframe, the mapping value of DL DAI of the second type for any downlink HARQ transmission in the time-frequency bundling window is used to indicate: and starting from the starting point of the time-frequency binding window until the time unit of any downlink HARQ transmission or the time unit of the DL-Assignment, and counting the HARQ feedback units sent by the base station on all carriers.

13. The method of claim 11, wherein when the time-frequency bundling window comprises a plurality of downlink subframes,

14. The method of claim 11, wherein the mapping value of the second type DL DAI for any downlink HARQ transmission within the time-frequency bundling window is used to indicate: starting from the starting point of the time-frequency binding window to the end point of the time-frequency binding window, or starting from the starting point of the time-frequency binding window to the last time unit of the subframe where any downlink HARQ transmission is located in the time-frequency binding window, the total number of HARQ feedback units expected to be sent by the base station on all carriers, or the total number of HARQ feedback units actually sent.

15. The method as claimed in claim 14, wherein the total number of HARQ feedback units sent by the base station is less than or equal to the mapping value of the second type DL DAI of the downlink HARQ transmission before the current time, and the UE performs the feedback of the HARQ-ACK bits according to the mapping value of the second type DL DAI of the downlink HARQ transmission; or the total number of the HARQ feedback units actually sent by the base station is larger than the mapping value of the second type DL DAI of the downlink HARQ transmission before the current time, the base station updates the mapping value of the second type DL DAI corresponding to the current downlink HARQ transmission, and the UE carries out the feedback of the HARQ-ACK bits according to the updated mapping value of the second type DL DAI.

16. The method of claim 11, wherein the mapping value of the second type DL DAI for any downlink HARQ transmission within the time-frequency bundling window is used to indicate: the HARQ feedback units in any downlink HARQ transmission are the last X HARQ feedback units on all carriers from the start of the time-frequency bundling window to the time unit in which any downlink HARQ transmission or DL Assignment is located, where X is a set positive integer and corresponds to different mapping values of the second type of DL DAI, and the values of X are the same or different.

17. The method of claim 11, wherein the mapping value of the second type DL DAI for any downlink HARQ transmission within the time-frequency bundling window is used to indicate: the HARQ feedback units in any downlink HARQ transmission are the last Y HARQ feedback units expected to be sent by the base station on all carriers from the start point of the time-frequency bundling window to the time unit where any downlink HARQ transmission or DL Assignment is located, Y is a set positive integer and corresponds to different mapping values of the second class of DL DAI, and the values of Y are the same or different.

18. A method for receiving HARQ-ACK information, comprising:

19. The method of claim 18, wherein when the time-frequency bundling window comprises only one downlink subframe,

20. The method of claim 18, wherein when the time-frequency bundling window comprises a plurality of downlink subframes,

21. The method according to any of claims 18 to 20, wherein a second type DL DAI corresponding to the downlink HARQ transmission is carried in the DL-Assignment;

22. The method of claim 21, wherein when the time-frequency bundling window only includes one downlink subframe, the mapping value of DL DAI of the second type for any downlink HARQ transmission in the time-frequency bundling window is used to indicate: and starting from the starting point of the time-frequency binding window until the time unit of any downlink HARQ transmission or the time unit of the DL-Assignment, and counting the HARQ feedback units sent by the base station on all carriers.

23. The method of claim 21, wherein when the time-frequency bundling window comprises a plurality of downlink subframes,

24. The method of claim 21, wherein the mapping value of the second type DL DAI for any downlink HARQ transmission within the time-frequency bundling window is used to indicate: starting from the starting point of the time-frequency binding window to the end point of the time-frequency binding window, or starting from the starting point of the time-frequency binding window to the last time unit of the subframe where any downlink HARQ transmission is located in the time-frequency binding window, the total number of HARQ feedback units expected to be sent by the base station on all carriers, or the total number of HARQ feedback units actually sent.

25. The method as claimed in claim 24, wherein the total number of HARQ feedback units sent by the base station is less than or equal to the mapping value of the second type DL DAI of the downlink HARQ transmission before the current time, and the UE performs the feedback of the HARQ-ACK bits according to the mapping value of the second type DL DAI of the downlink HARQ transmission; or the total number of the HARQ feedback units actually sent by the base station is larger than the mapping value of the second type DL DAI of the downlink HARQ transmission before the current time, the base station updates the mapping value of the second type DL DAI corresponding to the current downlink HARQ transmission, and the UE carries out the feedback of the HARQ-ACK bits according to the updated mapping value of the second type DL DAI.

26. The method of claim 21, wherein the mapping value of the second type DL DAI for any downlink HARQ transmission within the time-frequency bundling window is used to indicate:

27. A device for feeding back HARQ-ACK information, comprising: the device comprises a receiving unit, a detecting unit and a feedback unit;

28. An apparatus for receiving HARQ-ACK information, comprising: a transmitting unit and a receiving unit;