WO2017194022A1

WO2017194022A1 - Method, device, and system for transmitting downlink control information

Info

Publication number: WO2017194022A1
Application number: PCT/CN2017/084279
Authority: WO
Inventors: 石靖; 夏树强; 左志松; 张雯; 韩祥辉; 任敏
Original assignee: 中兴通讯股份有限公司
Priority date: 2016-05-13
Filing date: 2017-05-15
Publication date: 2017-11-16

Abstract

Provided in embodiments of the present disclosure are a method, device, and system for transmitting downlink control information. The method comprises: carrying, by means of at least one from a legacy PDCCH, EPDCCH, and sPDCCH, DCI of UE for scheduling an sTTI; and sending to a terminal the carried DCI, wherein service channels to be scheduled by the DCI comprises at least one of the following: only service channels within the sTTI; service channels within the sTTI or service channels within a TTI of 1 ms; and service channels within the sTTI and service channels within a TTI of 1 ms. The embodiments of the present disclosure solve the problem of the related art in which lack of support for a short TTI and downlink control information of related service scheduling thereof exists in low-latency communication scenarios, and provide implementation schemes to support short TTI scheduling and related service scheduling with variable TTI lengths, thus ensuring that latency-related communication requirements are met.

Description

Method, device and system for transmitting downlink control information

Technical field

The present disclosure relates to the field of communications, and in particular, to a method, an apparatus, and a system for transmitting downlink control information.

Background technique

With the 4th Generation mobile communication technology (4G, the 4th Generation mobile communication technology) Long Term Evolution (LTE), the Long Term Evolution (LTE-Advance/LTE-A, Long-Term Evolution Advance) system is commercially available. More and more perfect, the technical requirements for the next-generation mobile communication technology, the 5th Generation mobile communication technology (5G), are also getting higher and higher. It is widely believed in the industry that next-generation mobile communication systems should have features such as ultra-high speed, ultra-high capacity, ultra-high reliability, and ultra-low-latency transmission characteristics. For the ultra-low latency index in 5G systems, it is currently recognized that the air interface delay is on the order of 1 ms.

A method for effectively implementing the ultra-low latency is to reduce the processing delay interval by reducing the transmission time interval (TTI) of the LTE system to support the characteristic requirement of the above 1 ms air interface delay. At present, there are two methods for reducing TTI, one is to reduce the duration of a single OFDM symbol by expanding the subcarrier spacing of an Orthogonal Frequency Division Multiplexing (OFDM) system. The method is in a 5G high frequency communication system. It is involved in both ultra-dense networks; another method is to reduce the TTI length by reducing the number of OFDM symbols in a single TTI as currently discussed by 3GPP. The advantage of this method is that it can be fully compatible with current LTE systems. This article focuses on the latter method.

The downlink control information (DCI, Downlink Control Information) in the LTE system is carried by the downlink control channel (PDCCH) of the resource region occupying the first 0-4 OFDM symbols in the system bandwidth, or by using the downlink data traffic channel. Enhanced downlink control channel (ePDCCH, Enhanced Physical Downlink) of some PRB resource areas in (PDSCH, Physical Downlink Shared Channel) Control Channel) can schedule 1ms TTI services. Compared with the current 1 ms TTI length subframe, the shortened TTI with fewer OFDM symbols is used as a new granular short TTI (sTTI), the length of the sTTI is less than 1 ms, and the possible length is 1-7 OFDM symbols. .

In view of the lack of downlink control information supporting short TTI and its related service scheduling in the low-latency communication scenario in the related art, an effective solution has not been given yet.

Public content

The embodiments of the present disclosure provide a method, an apparatus, and a system for transmitting downlink control information, so as to at least solve the problem of lacking downlink control information supporting short TTI and related service scheduling in a low latency communication scenario in the related art.

According to an embodiment of the present disclosure, a method for transmitting downlink control information is provided, including: carrying, by using at least one of a legacy physical downlink control channel legacy PDCCH, an enhanced physical downlink control channel ePDCCH, and an sPDCCH, a UE for scheduling sTTI a DCI, where the sPDCCH is a physical downlink control channel in the sTTI, and the bearer is sent to the terminal, where the DCI is used for scheduling the traffic channel, including at least one of the following: only the traffic channel in the sTTI; Traffic channel or traffic channel in 1ms TTI; traffic channel in sTTI and traffic channel in 1ms TTI.

Optionally, when the DCI is used to schedule a traffic channel, at least one of the following manners: the DCI of the UE for scheduling the sTTI is the same as the DCI for scheduling the 1 ms PDSCH, and is distinguished by the RNTI. And distinguishing by different values of different types of RNTIs, or by different values of the same type of RNTIs; the DCIs of the UEs for scheduling sTTIs and the DCIs for scheduling 1ms PDSCHs are located in different search spaces; The DCI of the UE for scheduling the sTTI is distinguished by the indication flag in the first-level DCI of the first-level DCI or the two-level DCI for scheduling the traffic channel in the 1 ms TTI or for scheduling the traffic channel in the sTTI.

Optionally, the message carried by the traffic channel in the 1 ms TTI includes at least one of the following: a UE unicast message, or a cell broadcast message, or a public message of a group of UEs, or a cell System change message notification information for a level or group of UEs.

Optionally, when the downlink control information is two-level DCI, the scheduling information of the traffic channel is indicated by at least one of the following: the first level and the second level of the two-level DCI together form complete scheduling information; The second level in the DCI contains complete scheduling information.

Optionally, the method further includes: using one of the modes or pre-defining one of the modes by the eNB by using a high layer signaling SIB or RRC notification.

Optionally, the first-level DCI of the two-level DCI includes at least one of the following information: information indicating a parameter required for detecting an sPDCCH carrying a second-level DCI, where the second-level DCI includes scheduling sPDSCH and/or a second-level DCI of the sPUSCH; information indicating a DMRS port or a reserved RE when the sPDCCH and/or sPDSCH rate of the second-level DCI is matched; and demodulation using the pilot of the sPDCCH and/or the sPDSCH carrying the second-level DCI Information of CRS and/or DMRS; information indicating a transmission mode of sPDSCH; information indicating whether sPDCCH and/or sPDSCH carrying the second-level DCI is used based on CRS demodulation; indicating sPDCCH carrying the second-level DCI and/or Whether the sPDSCH is based on the information of the CRS when demodulating the DMRS; indicating the information of the PRB location of the DMRS used when the sPDCCH and/or the sPDSCH carrying the second-level DCI is demodulated; indicating the frequency domain position of the downlink DL sTTI band and/or Information of the uplink UL sTTI band frequency domain location; information indicating the length of the DL sTTI and/or the length of the UL sTTI; information indicating the number of DL sTTI bundling transmissions and/or the number of UL sTTI bundling transmissions.

Optionally, the parameters required for detecting the sPDCCH that carries the second-level DCI include at least one of the following: an aggregation level, a number of candidate sets, a search space frequency domain location, a search space time domain location, an sPDCCH scrambling parameter, and an sPDCCH usage. DMRS scrambling parameters, sPDCCH transmission mode, DMRS port used for sPDCCH demodulation.

Optionally, when the first-level DCI of the two-level DCI includes information indicating a parameter required for detecting sPDCCH of the second-level DCI, the first-level DCI is indicated on a parameter of the RRC or SIB configuration. A subset of the parameters of the RRC or SIB configuration, the subset comprising a subset of the parameter categories, and/or a subset of the parameter value ranges.

Optionally, the second-level DCI of the two-level DCI includes at least one of the following information: when the two-level DCI forms a complete scheduling information, the second-level DCI includes information about resource allocation and is in the first An indication based on resource allocation in the first-level DCI; when the second level of the two-level DCI includes complete scheduling information, the second-level DCI includes information of resource allocation; indicating sPDSCH and/or sPUSCH resources Allocation information; information indicating a DMRS port or a reserved RE when the sPDSCH rate is matched; information indicating a PRB position where the DMRS is used for sPDSCH demodulation; information indicating a length of the DL sTTI and/or a length of the UL sTTI; indicating DL The sTTI binds the number of transmissions and/or the number of UL sTTI binding transmissions.

Optionally, an update period of the first-level DCI in the two-level DCI is configured by a high-level signaling SIB or RRC.

Optionally, in the case that the sPDCCH is based on DMRS demodulation, the method further includes: when the DMRS is shared with the sPDSCH of the UE, the usage principle of the sPDSCH port includes at least one of the following: at RI=1 The DMRS with the same port as the sPDCCH is used; when RI=2, the same port as the DMRS where the sPDCCH is located is used; when RI>2, the same port as the DMRS where the sPDCCH is located is used preferentially, and then the DMRS with the sPDCCH is used. The sPDSCH port is used to indicate the sPDSCH port by using the sPDCCH transmission mode. When the DMRS is shared with the sPDSCH that is not the UE, the sPDSCH port usage principle includes at least one of the following: preferentially using the RE location of the DMRS with the sPDCCH. The same port, and secondly uses a port different from the RE location where the DMRS of the sPDCCH is located.

Optionally, the DMRS resource location adopts different occupation manners according to whether the sPDCCH and the sPDSCH share the DMRS.

Optionally, when the DMRS frequency domain location shared by the sPDCCH and the sPDSCH is located in a part of the PRB, the DMRS frequency domain location shared by the sPDCCH and the sPDSCH includes at least one of the following: only in the PRB where the sPDCCH is located; at least in the PRB where the sPDCCH is located Medium; located in the PRB of the intermediate interval selected by the sPDCCH or sPDSCH.

Optionally, the scrambling initialization method of the sPDCCH includes: the scrambling initialization method of the sPDCCH is independently scrambled in a subframe or in each sTTI in a radio frame, where the first sTTI or the legacy PDCCH region in the subframe sPDCCH scrambling initialization is satisfied

c _init is the scrambling initialization value, n _s is the slot number,

Is the cell identification number.

Optionally, when the DCI is used to schedule a traffic channel in a 1 ms TTI, the scheduling of the 1 ms TTI traffic channel with reduced processing delay or the scheduling delay of the 1 ms TTI traffic channel is not reduced, and the scheduling manner includes the following at least One: 1ms TTI delay is reduced and 1ms TTI delay is not reduced. Uniform DCI is used. When the content in the DCI is implicitly determined to be less than the preset TBS threshold, the 1ms TTI delay is reduced. Otherwise, The 1 ms TTI delay does not decrease; the 1 ms TTI delay decreases and the 1 ms TTI delay does not decrease. The unified DCI is used, and the independent bit field display in the DCI indicates whether to perform 1 ms TTI delay reduction; 1 ms TTI delay decreases and 1 ms TTI Do not reduce the use of the respective DCI format.

Optionally, when scheduling the 1 ms TTI service channel by using the DCI, the method further includes: performing, by using the high layer signaling SIB or the RRC, whether to perform the 1 ms TTI delay reduction.

Optionally, when the 1 ms TTI processing delay is decreased, the uplink data scheduling delay or the downlink data feedback delay k satisfies 0<k<4 and is an integer, and the value of k includes at least one of the following: an eNB and The UE side uses the same fixed k value, or the eNB and the UE side respectively use different fixed k values; the downlink and uplink use the same fixed k value, or the downlink and uplink respectively use different fixed k values; pass DCI or SIB or RRC Notifying the eNB and the UE side of the same k value, or notifying the eNB and the UE side of different k values by DCI or SIB or RRC; notifying the same k value for downlink and uplink by DCI or SIB or RRC, or by DCI or SIB Or RRC notifies the downlink and uplink of different k values.

Optionally, when the DCI is used to schedule an uplink traffic channel with a 1 ms TTI delay or sTTI, indicating that the uplink HARQ process ID and/or the redundancy version RV includes at least one of the following manners: when the 1 ms TTI delay is not used. The fixed bit field in the DCI is re-interpreted and then indicated; indicated by the independent bit field in the DCI; the CRC implicit indication is scrambled by different RNTI values.

Optionally, when the DCI is a single-level DCI or a two-level DCI, The sPDCCH resource mode includes at least one of the following manners: when the sPDCCH is included in the sPDSCH frequency domain range, or when there is only one sPDCCH in the search space, the sPDSCH frequency domain is excluded by default. All the resources except the sPDCCH are allowed to be used, or 1 bit in the DCI indicates whether the remaining resources in the search space where the sPDCCH is located are allowed to be used; when there are multiple sPDCCHs in the search space, when the candidate set fills the search space, the indication is not a candidate set to be used; indicating an unused control channel unit when the control channel unit occupies the search space; indicating an unused resource unit group or resource block when the resource unit group or the resource block occupies the search space; Indicates unused resource units when the search space is filled.

Optionally, the indication range corresponding to the indication includes at least one of: a resource indicating that the sPDCCH is not used in the sPDSCH frequency domain range; a resource indicating that the sPDCCH is not used in the sTTI band frequency domain range; indicating in the SS where the sPDCCH is located A resource that is not used by the sPDCCH; indicates resources that are not used by the sPDCCH in all SS or sTTI band frequency domain ranges.

Optionally, the short control channel unit sCCE used by the sPDCCH is composed of a short resource unit group sREG, and the composition manner includes at least one of the following manners: one sCCE is composed of a fixed number of sREGs; One sCCE consists of a different number of sREGs.

Optionally, according to different preset conditions, the 1 sCCE is composed of different numbers of sREGs, including: when there is a cell reference signal CRS, 1sCCE=4sREG; when there is no CRS, 1sCCE=3sREG.

Optionally, when the DCI schedules the traffic channel in the sTTI, and the sTTI length is unknown, the method for detecting the DCI includes at least one of the following: attempting blind detection according to different sPDCCH detection positions corresponding to different sTTI lengths; and corresponding sTTI lengths The sPDCCH detection positions are the same, but the respective pilot patterns in different sTTI lengths are respectively attempted to be demodulated in different rate matching manners; the sPDCCH detection positions corresponding to different sTTI lengths are the same and the same rate is used according to the pilots in the same position in the sPDCCH region at the same rate. The matching method attempts to demodulate.

Optionally, the DCI supports scheduling different TTI lengths and supporting whether the delay is reduced. When the channel is used, the DCI is used in at least one of the following: the TTI=2 OFDM symbols, TTI=1 time slots, 1 ms TTI delay reduction, and 1 ms TTI delay are not reduced, all using the same DCI format; 1ms TTI delay reduction and 1ms TTI delay does not decrease using one DCI format, TTI=2 OFDM symbols and TTI=1 time slots use another DCI format or two-level DCI; 1ms TTI delay does not decrease use one DCI format, TTI=2 OFDM symbols, TTI=1 time slots and 1ms TTI delay reduction using another DCI format or two-stage DCI; 1ms TTI delay reduction, 1ms TTI delay does not decrease, and TTI=1 One time slot uses one DCI format, TTI=2 OFDM symbols use another DCI format or two-level DCI; 1 ms TTI delay does not reduce the use of one DCI format, and 1 ms TTI delay reduces the use of another DCI format, TTI=2 OFDM symbols and TTI=1 time slots use another DCI format or two-stage DCI; 1ms TTI delay does not decrease using one DCI format, 1ms TTI delay is reduced and TTI=1 time slot is used A DCI format, TTI = 2 OFDM symbols using another DCI format or two-level DCI.

According to another embodiment of the present disclosure, a method for transmitting downlink control information is provided, including: receiving, by using at least one of a legacy physical downlink control channel legacy PDCCH, an enhanced physical downlink control channel ePDCCH, and an sPDCCH, for scheduling The downlink control information DCI of the terminal UE with a short transmission interval sTTI, the sPDCCH is a physical downlink control channel in the sTTI; the UE uses the DCI for scheduling; wherein the DCI is used for scheduling the traffic channel including at least the following One: only the traffic channel in the sTTI; the traffic channel in the sTTI or the traffic channel in the 1 ms TTI; the traffic channel in the sTTI and the traffic channel in the 1 ms TTI.

According to another embodiment of the present disclosure, a transmission apparatus for downlink control information is provided. The base station includes: a bearer module, configured to carry, by using at least one of a legacy physical downlink control channel legacy PDCCH, an enhanced physical downlink control channel ePDCCH, and an sPDCCH, a DCI of a UE for scheduling an sTTI, where the sPDCCH is a physical downlink in the sTTI And a sending module, configured to send the bearer DCI to the terminal, where the DCI is used for scheduling the traffic channel, including at least one of: a traffic channel only in the sTTI; a traffic channel in the sTTI or a 1 ms TTI Traffic channel in; traffic channel in sTTI and traffic channel in 1ms TTI.

According to another embodiment of the present disclosure, another apparatus for transmitting downlink control information is provided, where the terminal UE includes: a receiving module, configured to receive a legacy physical downlink control channel legacy PDCCH, an enhanced physical downlink control channel ePDCCH, The downlink control information DCI of the UE for scheduling the short transmission time interval sTTI, the sPDCCH is a physical downlink control channel in the sTTI, and the scheduling module is configured to use the DCI for scheduling, where The traffic channel used for scheduling by the DCI includes at least one of: a traffic channel only in the sTTI; a traffic channel in the sTTI or a traffic channel in the 1 ms TTI; a traffic channel in the sTTI and a traffic channel in the 1 ms TTI.

According to still another embodiment of the present disclosure, a transmission system for downlink control information, including the foregoing transmission device for downlink control information of a base station, and the foregoing transmission device for downlink control information of the terminal are provided.

According to still another embodiment of the present disclosure, a storage medium is also provided. The storage medium is configured to store program code for performing: transmitting, by at least one of legacy PDCCH, ePDCCH, sPDCCH, DCI of a UE for scheduling sTTI, the sPDCCH being a physical downlink control channel in an sTTI; The DCI is sent to the terminal; wherein the traffic channel used by the DCI for scheduling includes at least one of: a traffic channel only in the sTTI; a traffic channel in the sTTI or a traffic channel in the 1 ms TTI; a traffic channel in the sTTI And the traffic channel in the 1ms TTI.

Optionally, the storage medium is further configured to store program code for performing the following steps: receiving, by using at least one of legacy PDCCH, ePDCCH, and sPDCCH, for scheduling sTTI The DCI of the UE is the physical downlink control channel in the sTTI; the UE uses the DCI for scheduling; wherein the traffic channel used by the DCI for scheduling includes at least one of the following: a traffic channel only in the sTTI Traffic channel in sTTI or traffic channel in 1ms TTI; traffic channel in sTTI and traffic channel in 1ms TTI.

With the embodiment of the present disclosure, the DCI of the UE for scheduling the sTTI is carried in at least one of the legacy PDCCH, the ePDCCH, and the sPDCCH, and is sent to the UE, which solves the short support in the low-latency communication scenario in the related art. The problem of downlink control information for TTI and its related service scheduling is given. The implementation scheme of supporting short TTI scheduling and its related different length TTI service scheduling is given to ensure the delay communication requirement.

DRAWINGS

The drawings described herein are provided to provide a further understanding of the present disclosure, which is a part of the present disclosure, and the description of the present disclosure and the description thereof are not intended to limit the disclosure. In the drawing:

FIG. 1 is a flowchart of a method for transmitting downlink control information according to an embodiment of the present disclosure;

2(a) is a diagram 1 showing an example of the composition of sCCE/sREG according to an embodiment of the present disclosure;

2(b) is a diagram 2 showing an example of the composition of sCCE/sREG according to an embodiment of the present disclosure;

2(c) is an exemplary diagram 3 of a manner of composition of sCCE/sREG according to an embodiment of the present disclosure;

FIG. 3 is a structural block diagram of a transmission apparatus for downlink control information according to an embodiment of the present disclosure; FIG.

4 is a flowchart of another method for transmitting downlink control information according to an embodiment of the present disclosure;

FIG. 5 is a structural block diagram of another transmission apparatus for downlink control information according to an embodiment of the present disclosure; FIG.

6 is a structural block diagram of a transmission system of downlink control information according to an embodiment of the present disclosure;

7 is a schematic diagram of an sPDCCH occupying resources only in a portion of an sPRB in a first OFDM symbol in an sTTI according to a preferred embodiment of the present disclosure;

FIG. 8 is a DMRS requirement in a PRB where an sPDCCH is located according to a preferred embodiment of the present disclosure. Schematic diagram shared with sPDSCH;

9 is a schematic diagram of a portion of a PRB in which a sPDSCH is located, without sharing a DMRS with an sPDCCH, in accordance with a preferred embodiment of the present disclosure.

detailed description

The present disclosure will be described in detail below with reference to the drawings in conjunction with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

It is to be understood that the terms "first", "second", and the like in the specification and claims of the present disclosure are used to distinguish similar objects, and are not necessarily used to describe a particular order or order.

Considering the DCI of the scheduled sTTI service to be used and how the DCI scheduling the sTTI service supports 1 ms TTI and sTTI scheduling simultaneously, it is necessary to provide a transmission method for downlink control information suitable for low latency requirements.

Based on the above considerations, the embodiments of the present disclosure provide a method for transmitting downlink control information, which can solve the problem of designing downlink control information in short TTIs with fewer OFDM symbols, and support short TTI scheduling and different length TTI service scheduling. Problem, guarantee delay communication needs.

In this embodiment, a method for transmitting downlink control information is provided. FIG. 1 is a flowchart of a method for transmitting downlink control information according to an embodiment of the present disclosure. As shown in FIG. 1, the method includes the following steps:

Step S102: Carrying, by using at least one of a legacy physical downlink control channel (Legacy PDCCH), an enhanced physical downlink control channel (ePDCCH), and an sPDCCH (Short PDCCH), a downlink (UE) for scheduling a short transmission time interval (sTTI) Control information (DCI), the sPDCCH is a physical downlink control channel in the sTTI;

Step S104, the bearer of the DCI is sent to the terminal.

The service channel in which the DCI is used for scheduling includes at least one of the following:

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.

In this embodiment, the DCI of the UE for scheduling the sTTI is carried in at least one of the legacy PDCCH, the ePDCCH, and the sPDCCH, and is sent to the UE, which solves the problem that the short TTI is supported in the low-latency communication scenario in the related art. For the problem of downlink control information related to service scheduling, an implementation scheme supporting short TTI scheduling and its associated different length TTI service scheduling is given to ensure delay communication requirements. Legacy PDCCH and ePDCCH in this paper mainly describe a legacy PDCCH and an ePDCCH in an LTE system.

As a preferred implementation manner, when the DCI is used to schedule a traffic channel, at least one of the following manners may be included:

A. The size of the DCI of the UE for scheduling the sTTI is the same as the size of the DCI for scheduling the 1 ms PDSCH, and is distinguished by the RNTI, including distinguishing by different values of different types of RNTIs. Or distinguish by different values of the same type of RNTI. For example, the different scrambling code RNTI of the first-level DCI of the first-level DCI or the two-level DCI may be used to distinguish whether the DCI is used for scheduling a traffic channel in a 1 ms TTI or for scheduling a traffic channel in an sTTI. Preferably, it may be used to schedule only the traffic channel in the sTTI; or to schedule a traffic channel in the sTTI or a traffic channel in the 1 ms TTI; or to schedule a traffic channel in the sTTI and a traffic channel in the 1 ms TTI.

B. The DCI of the UE for scheduling the sTTI and the DCI for scheduling the 1 ms PDSCH are located in different search spaces. It can be distinguished by restricting the search space (Search Space, referred to as SS) in which the DCIs of different service channels are scheduled, for example, respectively located in CSS or USS, respectively in the Legacy search space and the newly defined search space. Preferably, it can be used to schedule only the traffic channel in the sTTI; schedule the traffic channel in the sTTI or the traffic channel in the 1 ms TTI; schedule the traffic channel in the sTTI and the traffic channel in the 1 ms TTI.

C. Differentiate the DCI of the UE for scheduling the sTTI by using the indication identifier in the first-level DCI or the first-level DCI of the two-level DCI to schedule the traffic channel in the 1 ms TTI or to schedule the traffic channel in the sTTI. The method is preferably used to schedule a traffic channel in sTTI or 1 ms The situation when the traffic channel is in the TTI.

Optionally, the message carried by the traffic channel in the 1 ms TTI may include at least one of the following: a UE unicast message, or a cell broadcast message, or a common message of a group of UEs, or a system change of a cell level or a group of UEs. Message notification information.

As a preferred implementation, the downlink control information (DCI) may be a first-level DCI or a two-level DCI, where the traffic channel scheduling information indicated when the DCI is two-level DCI may include at least one of the following: two-level DCI The first level and the second level together constitute complete scheduling information; the second level of the two-level DCI contains complete scheduling information.

For the above two modes, when the first-stage DCI and the second-level DCI in the two-stage DCI form a complete scheduling information, the terminal demodulates the slow DCI and skips to the next subframe to continue detecting the slow DCI without Detect the fast DCI in this sub-frame. When the second level of the two-stage DCI contains the complete scheduling information, the terminal demodulates the slow DCI and continues to detect the fast DCI in this subframe. For example, when the first-level DCI and the second-level DCI of the two-level DCI together form complete scheduling information, both the first-level and second-level DCIs contain resource allocation information and the second-level resource allocation is based on the first-level resource allocation. On the instructions. When the second-level DCI in the two-level DCI contains complete scheduling information, both the first-level DCI and the second-level DCI contain resource allocation information and the second-level resource allocation does not depend on the first-level resource allocation. Or the first-level DCI includes the detection information required to indicate the second-level DCI to reduce the second-level DCI detection complexity, but even if the first-level DCI is not detected, the terminal can still detect the parameters according to the high-level signaling RRC or SIB configuration. Second level DCI.

Alternatively, one of the above two methods may be used by the base station (eNB) through the high layer signaling RRC or SIB notification or one of the above two methods may be predefined.

Optionally, at least one of the following information may be included in the first level DCI:

Determining a parameter required for sPDCCH detection of a second-level DCI, where the second-level DCI includes a second-level DCI that schedules sPDSCH and/or sPUSCH, where the parameter may include an aggregation level, a number of candidate sets, and a search space frequency domain. At least one of a location, a search space time domain location, an sPDCCH scrambling parameter, a DMRS scrambling parameter used by the sPDCCH, an sPDCCH transmission mode, and a DMRS port used for sPDCCH demodulation;

Indicates a DMRS port or a reserved RE when the sPDCCH and/or the sPDSCH rate of the second-level DCI is matched, where the reserved RE is preferably an RE corresponding to all the DMRS ports, or an RE corresponding to the port occupying the same RE;

Indicating that the sPDCCH and/or sPDSCH demodulation carrying the second-level DCI uses pilot CRS and/or DMRS;

Indicating a transmission mode of the sPDSCH;

Determining whether to use the DMRS when the sPDCCH and/or the sPDSCH carrying the second-level DCI is demodulated based on the CRS;

Determining whether to use CRS when sPDCCH and/or sPDSCH carrying the second-level DCI is demodulated based on DMRS;

Indicate the PRB location of the DMRS used when demodulating the sPDCCH and/or sPDSCH carrying the second-level DCI;

Indicating a downlink (DL) sTTI band frequency domain location and/or an uplink (UL) sTTI band frequency domain location, wherein the frequency domain location may preferably be indicative of a portion of the LTE system bandwidth or All PRB;

Indicates the length (length) of the DL sTTI and/or the length (length) of the UL sTTI;

Indicates the number of DL sTTI bundling transmissions and/or the number of UL sTTI bundling transmissions.

Optionally, when the first-level DCI indicates a parameter required for detecting sPDCCH of the second-level DCI, indicating a subset of parameters of the RRC or SIB configuration based on parameters of the RRC or SIB configuration. The subset may include a subset of the parameter categories, and/or a subset of the parameter value ranges.

Optionally, the second level DCI may include at least one of the following information:

When the two levels of DCI together form complete scheduling information, the second level DCI includes resource allocation and is indicated on the basis of resource allocation in the first level DCI;

When the second level of the two-level DCI contains complete scheduling information, in the second level DCI Contains resource allocations;

Indicating sPDSCH and/or sPUSCH resource allocation information;

Indicates the DMRS port or the reserved RE when the sPDSCH rate is matched, and the reserved RE is preferably the RE corresponding to all the DMRS ports, or the RE corresponding to the port occupying the same RE;

Indicates the PRB location of the DMRS used for sPDSCH demodulation;

Optionally, an update period of the first-level DCI in the two-level DCI may be configured by a high-level signaling SIB or RRC. This method can be applied to the case where the fast DCI has complete scheduling information. When a slow DCI demodulation error occurs, but is still within the update period range, the previous slow DCI indication is used to reduce the fast DCI demodulation complexity.

As a preferred implementation manner, in a case where the sPDCCH is based on DMRS demodulation,

When the DMRS is shared with the sPDSCH of the UE, the sPDSCH port usage principle includes at least one of the following:

Use DMRS with the same port as sPDCCH when RI=1;

When RI=2, the same port as the RE location of the DMRS of the sPDCCH is used;

When RI>2, the port with the same RE location as the DMRS of the sPDCCH is preferentially used, and the port with the RE location of the DMRS of the sPDCCH is used secondly;

The sPDSCH port is indicated by the DCI in combination with the sPDCCH transmission mode. For example, the sPDSCH port may be not indicated when the sPDSCH is used in the DCI, or the same port as the RE where the sPDCCH is used by the sPDCCH, and the sPDCCH uses port x1, sPDSCH. Also use port x1, or use port x2 with the same RE location as port x1. The sPDSCH layer 2 transmission may not indicate, and the corresponding port is used according to the sPDCCH transmission mode. When the sPDCCH transmission mode uses the port x1, the sPDSCH uses the port x1 and x2 of the same RE position as the port x1, and the port x1 and y1 are used when the sPDCCH transmission mode is used. When sPDSCH makes Use port x1, x2 at the same RE position as port x1, or port y1, y2 at the same RE position as port y1, or use port x1, y1 (preferred), or indicate the port corresponding to the sPDCCH transmission mode, when sPDCCH transmission mode When port x1 is used, it indicates that sPDSCH uses ports x1 and x2 of the same RE position as port x1. When port x1 and y1 are used for sPDCCH transmission mode, sPDSCH uses port x1 and x2 of the same RE position as port x1, or is the same as port y1. Port y1, y2 of the RE position, or port x1, y1 (preferred). When the sPDSCH uses more than Layer 2 transmission, it may not indicate that the corresponding port is used according to the transmission mode. When the sPDCCH transmission mode uses port x1, the sPDSCH uses the port x1, x2, x3, ... of the same RE position as the port x1, when the sPDCCH is transmitted. When port x1 and y1 are used, sPDSCH uses port x1, x2, x3, ... at the same RE position as port x1, or port y1, y2, y3, ... at the same RE position as port y1, or uses port x1, y1, x2. Y2, ... (preferably), or port x1, x2, x3, ... indicating that the sPDSCH uses the same RE position as the port x1, and when the sPDCCH transmission mode uses the ports x1, y1, the sPDSCH uses the port x1, x2 of the same RE position as the port x1 , x3..., or port y1, y2, y3... at the same RE position as port y1, or using ports x1, y1, x2, y2, ... (preferred);

When the DMRS is shared with the sPDSCH that is not the UE, the sPDSCH port usage principle includes at least one of the following:

The port with the same RE location as the DMRS of the sPDCCH is preferentially used, and the port with the RE location of the DMRS of the sPDCCH is used next.

Optionally, the DMRS resource location may adopt different occupation manners according to whether the sPDCCH and the sPDSCH share the DMRS. For example, if the sPDCCH and the sPDSCH share the DMRS, the possible DMRS resource occupation manner is as follows. The partial PRB is located in the PRB where the sPDCCH is located, at least in the PRB where the sPDCCH is located, and is located in the PRB resource occupied by the sPDCCH or the sPDSCH. The selected PRB is medium; if the sPDCCH and the sPDSCH do not share the DMRS, the DMRS resource occupation mode may be equal to the PRB selected by each PRB and located at the middle interval of the PRB resources occupied by the sPDSCH.

Optionally, the DMRS frequency domain location shared by the sPDCCH and the sPDSCH is located in a part. When PRB, include at least one of the following occupation methods:

Only in the PRB where the sPDCCH is located;

At least in the PRB where the sPDCCH is located;

The PRB is located in the PRB of the intermediate interval of the PDCCH occupied by the sPDCCH or the sPDSCH. For example, the max{sPDCCH occupies the PRB resource, and the sPDSCH occupies the PRB resource}.

Optionally, the scrambling initialization method of the sPDCCH is that each sTTI in the subframe or the radio frame is independently scrambled, wherein the sPDCCH scrambling initialization in the first sTTI or the legacy PDCCH region in the subframe satisfies

c _init is the scrambling initialization value, n _s is the slot number,

It is the identification (ID) number of the cell.

As a preferred implementation manner, when the DCI is used to schedule a traffic channel in a 1 ms TTI, the scheduling of the 1 ms TTI traffic channel with reduced processing delay or the scheduling of the 1 ms TTI traffic channel without processing delay is supported. Including at least one of the following:

Manner 1: 1ms TTI delay is reduced and 1ms TTI delay is not reduced. Use unified DCI. When the value of the TBS is less than the preset TBS threshold in the DCI (for example, the resource allocation RA and the modulation and coding mode MCS), the TBS is small, and the 1 ms TTI delay can be reduced. Otherwise, the 1 ms TTI delay is supported. Not lowering.

Manner 2: 1 ms TTI delay is reduced and 1 ms TTI delay is not reduced. Use unified DCI. The display of the independent bit field in the DCI indicates whether to perform the 1 ms TTI delay reduction.

Mode 3: 1 ms TTI delay is reduced with 1 ms TTI delay is not reduced using the respective DCI format.

Optionally, when the 1 ms TTI processing delay is decreased, 0<k<4 and an integer, and the k value manner includes at least one of the following:

Manner 1: Fixed value, including eNB and UE side respectively using the same k value, or eNB Different values are used for the UE side and the UE side; the same k value is used for the downlink and uplink, respectively, or different k values are used for the downlink and uplink respectively.

Manner 2: non-fixed value, the k value is notified by DCI or SIB or RRC, including notifying the eNB and the UE side of the same k value, or notifying the eNB and the UE side of different k values; the same k for the downlink and uplink notifications Value, or different k values for downstream and upstream notifications.

Where k is the uplink data scheduling delay or the downlink data feedback delay. Currently, in the LTE system, k=4 for the FDD system and k≥4 for the TDD system. When the processing delay described here is reduced (hereinafter referred to as delay reduction), the delay is smaller than the current LTE system, and k is a positive integer less than 4.

Specifically, how to determine the execution delay of 1 ms TTI delay is mainly divided into dynamic and semi-static modes:

Dynamic mode:

Manner 1: In the DCI, when the small TBS is implicitly determined (by the resource allocation RA+ modulation coding scheme MCS), the 1 ms TTI delay is reduced. At this time, DCI has no effect. Of course, this method also needs to determine the limited TBS threshold size. TBS threshold: fixed or SIB/RRC configurable. From the perspective of different UE capabilities, the RRC is configured to configure the TBS threshold.

Manner 2: The DCI indicates whether to perform the 1ms TTI delay reduction. The TBS threshold is not needed at this time and is completely determined by the DCI dynamic scheduling. At this time, the DCI is a DCI that introduces a new bit field. For example, when the 1 ms TTI delay is reduced, the PUCCH resource indication and the newly designed RA may be added to the DCI. At this time, the small TBS does not necessarily perform the 1 ms TTI delay.

For mode two, when the DCI is still the existing format. Sub-method 1: Increase the execution condition of If used for latency reduction mode for format 0/4. At this time, adding the DCI size of the new bit field does not exceed the size of the original legacy format 0/4, that is, it needs to compress other bit fields (such as RA), and there is a new design. Sub-method 2: Add the bit field directly in format 0/4, otherwise reserved if not used. The corresponding format 1A may complement padding.

For mode two, when DCI is the new format. Whether other bit fields are new or not.

In addition, whether the 1ms TTI delay is reduced, including: through DCI or SIB/RRC 1 bit indicates whether to perform a 1 ms TTI delay reduction, or indicates one of the k value sets by x bit in DCI or SIB/RRC, or indicates a k value set by x bit in SIB/RRC.

In addition, both of the above methods can support only one or more values of k when the 1 ms TTI delay is reduced. For mode 1, when the k value is not unique, the RRC notification can be used. For the second mode, the k value is not unique and can be notified by DCI or RRC. In addition, when the 1 ms TTI delay is reduced, there are two cases: the eNB has the same k value as the UE, or the eNB has a different k value from the UE. For example, the eNB and the UE perform uplink and downlink scheduling and uplink and downlink feedback timing with the same k value, such as k=2, or the eNB and the UE respectively perform with different k values in consideration of different processing capabilities. Also, the k value is unique when the 1 ms TTI delay is reduced, and includes two cases: the eNB has the same k value as the UE, or the eNB and the UE have different k values. Example: k-value set {1, 2, 3, 4, (4, 2), (2, 4), (4, 3), (3, 4), (2, 3), (3, 2)} .

Semi-static mode:

Increase whether the high-level signaling SIB/RRC configuration performs 1ms TTI delay reduction.

Manner 1: 1ms TTI delay is reduced and 1ms TTI delay is not reduced. Use unified DCI. Same as dynamic one. At this time, the TBS cannot be too large, and only a small TBS is allocated semi-static.

Manner 2: 1 ms TTI delay is reduced and 1 ms TTI delay is not reduced. Use unified DCI. Same as dynamic mode two. It is completely determined by the schedule, and one of them is semi-statically executed.

Mode 3: 1 ms TTI delay is reduced with 1 ms TTI delay is not reduced using the respective DCI format. Use only one of them semi-static.

When there is no such high layer signaling, the default new UE can perform delay reduction. The difference is that when there is a high-level signaling configuration, the delay is configured when the new UE is not configured to perform 1 ms TTI, even if the small TBS does not perform the 1 ms TTI delay, and only when the high-level signaling configuration can be executed, the further TBS is performed. The 1ms TTI delay is reduced. When there is no high-level signaling configuration, for a new UE, when the small TBS is performed, the 1 ms TTI delay is definitely reduced.

When all TBS sizes can support the delay reduction, the above method is still applicable, but it is not necessary to distinguish whether it is a small TBS and a possible TBS threshold. If only a small TBS can perform k=2, the eNB configuration (semi-static configuration, but the actual timing dynamically changes with the TBS size) determines whether the terminal performs a 1 ms delay reduction in the small TBS, and an additional TBS threshold. Optional. If k=2 can be performed regardless of the TBS size, the eNB semi-statically configured terminal changes between k=2 and k=4 without DCI dynamic indication k=2 or k=4.

As a preferred implementation manner, when the DCI is used to schedule an uplink traffic channel with a 1 ms TTI delay or sTTI, indicating an uplink HARQ process number and or a redundancy version (RV) includes at least one of the following manners. :

Manner 1: When the 1 ms TTI delay is not reduced, the existing bit field in the DCI is re-interpreted and then indicated.

Manner 2: The independent bit field indication in the DCI.

Manner 3: The CRC implicit indication is scrambled by different RNTI values.

Specifically, when the PUSCH or the sPUSCH uses the asynchronous UL HARQ, the UL grant needs to introduce a UL HARQ process number (2 to 4 bits) and an RV (1 to 2 bits).

The possible methods are as follows:

Method 1: Use the existing DCI format (format)

Option 1: Existing bit field reinterpretation. For example, the UL HARQ process number 2 bits and the RV 1 bit are implemented by the DMRS CS/OCC bit field 3 bits and the DMRS CS/OCC fixed or RRC configuration of the UE.

Option 2: Pass RNTI. For example, the UL HARQ process number and the RV are determined by a plurality of different C-RNTIs of the UE. In this case, multiple C-RNTIs are allocated to the UE through the RRC, and the correspondence between the values of the different C-RNTIs and the process number and the RV version is clarified.

Method 2: DCI is a DCI that introduces a new bit field. That is, the UL HARQ process number and RV are independent bit fields.

Option 1: Add in existing format 0/4. DCI is still an existing format. Increase the UL HARQ process number and RV for format 0/4, that is, when the remaining delay does not decrease. In addition, format 1A may need to fill padding.

Option 2: DCI is the new format. After adding the UL HARQ process number and RV, whether other bit fields are newly designed or not.

In addition, for different size TTIs (such as TTI=2, 7, 14 symbols), the process number bit field size may use different size bit fields, or the size corresponding to the largest number of processes in different TTIs.

As a preferred implementation manner, when the DCI is a single-level DCI or any one-level DCI in a two-level DCI, indicating an unused sPDCCH resource manner includes at least one of the following manners:

Mode S1: When only the sPDCCH scheduling the sPDCCH in the sPDSCH frequency domain range or when there is only one sPDCCH in the search space, all resources except the sPDCCH may be used in the sPDSCH frequency domain by default, or in the DCI. The first bit indicates whether the remaining resources in the search space where the sPDCCH is located are usable.

Mode S2: when there are multiple sPDCCHs in the search space, indicating that the candidate set is not used when the candidate set fills the search space; indicating the unused control channel unit when the control channel unit fills the search space; Indicates an unused resource unit group or resource block when the group or resource block fills the search space; indicates an unused resource unit when the resource unit fills the search space;

Optionally, the indication range corresponding to the indication includes at least one of the following manners:

(Mode 1) A resource indicating that the sPDCCH is not used is indicated in the sPDSCH frequency domain range.

(Mode 2) Indicates resources that are not used by the sPDCCH in the sTTI band frequency domain range.

(Mode 3) A resource that is not used by the sPDCCH is indicated in a search space (referred to as SS) in which the sPDCCH is located.

(Mode 4) Indicates resources that are not used by the sPDCCH in all SS or sTTI band frequency domain ranges.

Specifically, considering two possible ways of sPDCCH resource occupation (TDM, FDM), indicating granularity considerations

When in the TDM mode and in the first OFDM symbol, mode 1: occupy all frequency domain resources: (similar to the PDCCH region frequency domain occupies full bandwidth). Indicates unused REG or RB (fine graininess); indicates unused CCE or candidate set (coarse granularity); (CRS position UE is known). Mode 2: Partial frequency domain resources: Indicates unused sREG or RB; indicates unused CCE or candidate set. Mode 2-1 When all UEs have only one short TTI SS, it indicates that no RB or sCCE is used. Mode 2-2 When all UEs have more than one short TTI SS, when the sPDSCH is only possible to use unused resources in the SS, it indicates that the RB or sCCE is not used in the SS, and is applicable to the DL service self-contained DL control. . When the sPDSCH may use other resources not used in the SS, it is necessary to indicate that the RBs are not used in all the SSs, and also indicate the frequency domain range of all the SSs.

When the FDM mode (both OFDM symbols can be occupied), mode 1 occupies resources in a (2 OFDM symbol, 1 RB) minimum granularity mode: indicates an unused RB or CCE or candidate set. Mode 2 is (1 OFDM symbol, 1 RB) minimum granularity mode or when EREG occupies resources: indicates an unused sCCE or a candidate set. In this case, as in the TDM mode, there is also a problem that all UEs have one or more short TTI SSs. When there are multiple short TTI SSs, when the sPDSCH may use unused resources in other SSs, it also indicates the frequency domain range of all SSs.

The cost of indicating the unused resources of the sPDCCH is considered: the resource granularity is assumed to be the candidate set > sCCE > RB / sREG > RE:

For the above method S2, the overhead is considered, and the DCI should not be too large, and it is expected to be about 2 to 4 bits. When the candidate set fills the search space, the unused candidate set is indicated, and when all the detected candidate sets occupy the SS: the candidate set numbers that are not used in the N candidate sets are indicated. Determination of N: Select 1. Only 1 SS or only SS for its own when there are multiple SSs (multi-UE shared SS): Consider the total number of blind detections in each sTTI, and the N value is based on the candidate set. In the case of 2 to 4, the unused candidate set overhead is saved by 2-4 bits, and then the corresponding sCCE or RB or sREG resource can be converted. When the 2.sPDSCH self-contained sPDCCH is selected (single UE exclusive SS): only 1 bit can be used to indicate whether resources other than sPDCCH occupancy are available or not. Select 3. When there are multiple SSs: the N value corresponding to the entire symbol in the sTTI band or the scheduled sPDSCH range. The overhead is greater than option 1. When the control channel unit fills the search space, the unused control channel unit is indicated, and the candidate set does not occupy the SS, indicating the unused sCCE sequence number in the N sCCEs, similar to the above, the overhead is increased; Or a resource block fills the search space Indicates an unused resource unit group or a resource block. In this case, the CCE does not fill the SS, indicating that the sREG or RB sequence number is not used in the N sREGs or RBs, and the overhead is larger; when the resource unit fills the search space, the indication is not The resource unit used is the most expensive at this time.

For the case where the S1SCH does not need to be instructed, the sPDCCH may be used as the resource that is not used for the sPDCCH, and may be used when allocating the sPDSCH resource, that is, the sPDCCH is not used when the resource used by the sPDSCH is allocated. The resources are allocated to the sPDSCH, ie no additional signaling indication is required. In this case, different symbols belong to different sPDSCHs in order to avoid the same PRB. A limit may be added. The RB occupied by the sPDCCH must be the RB occupied by the sPDSCH, and the RA in the DCI only needs to allocate the RBs of other locations. However, if sPDSCH is occupied by sREG as granularity, there are two restrictions on sPDCCH, one is sCCE/sREG is composed of RBG, and the other is sCCE/sREG is still composed of RB but allocated Only one RB of the four RBs corresponding to each RBG can be allocated in the SS.

For the composition of sCCE/sREG (ie, sCCE and/or sREG), at least one of the following methods is included:

Mode 1:1 sREG (1 OFDM, 1 PRB) = 12 RE, 1 s CCE = 3 REG.

At this time, there is 36 available REs in 1sCCE when there is no CRS. When there is CRS, 24RE is available in 1CCE; if there is another DMRS, the corresponding available RE will be less.

Mode 2: 1 sREG (1 OFDM, 1 PRB) = 12 RE, and the number of sREGs constituting the sCCE is not unique.

According to whether there is CRS (that is, whether there is CRS according to sREG, or whether the symbol of sREG has CRS), the number of sREGs constituting sCCE is different. At this time, 1sREG(1OFDM, 1PRB)=12RE, see Table 5 below:

table 5

Mode 3: Still use REG, CCE definition. Not applicable when using DMRS demodulation.

Mode 4: sREG is the sequence number of the X PRBs after subtracting the CRS and or DMRS. Then, sCCE is formed according to the ECCE method.

Mode 5: Unified with the traffic channel, sCCE/sREG is based on RBG or PRG. For example, the sCCE is composed of 4 REBs, that is, 1 REG. In this case, the sCCE includes 4 sREGs, and 1 sREG consists of 1 RB.

Example 1: TDM mode 1, as shown in FIG. 2(a), the sPDCCH region is all the first OFDM symbols, the resources occupied by the sPDCCH of the UE1 are PRB1, 3, and 5, and the other sPDCCHs occupy the PRBs 4, 6, and 8. The sPDSCH occupied resource of UE1 is PRB1-8. At this time, according to the mode 1, it is required to indicate that the

PRBs

2 and 7 are not used by the sPDCCH, and according to the mode 2, it is necessary to indicate that the

PRBs

2, 7, ... are not used by the sPDCCH

Example 2: In TDM mode 2, as shown in Figure 2(b), only one short TTI SS is PRB1-8, the sPDSCH of UE1 occupies PRB1-10, and the sPDCCH of UE1 occupies PRB1, 3, and 5. The

PRB

2, 7 is not used by the sPDCCH according to the

mode

1 or 2.

Example 3: TDM mode 2, as shown in Figure 2(b), there are only 2 short TTI SSs, the first SS is PRB1-6, the second SS is PRB3-8, and the sPDSCH of UE1 occupies PRB1-10. The sPDCCH of UE1 is located in the first SS and occupies PRB1, 3, and 5. In this case, only PRB2 and 7 are not used by sPDCCH according to

mode

1 or 2, and the frequency domain range of the second SS needs to be notified to the UE1.

Example 4: In the FDM mode, as shown in Figure 2(c), only one short TTI SS is PRB1-4, the sPDCCH of UE1 occupies CCE1, the other sPDCCH occupies CCE2, and the remaining CCE3 is unused. The scheduled sPDSCH of UE1 occupies PRB1-10. At this time, according to

mode

1 or 2, CCE3 is not used in the SS.

As a preferred implementation manner, when the DCI schedules a traffic channel in the sTTI, when the sTTI length is unknown, the manner of detecting the DCI includes at least one of the following:

Mode 1: respectively, try blind detection according to different sTTI lengths, including: different sPDCCH detection positions corresponding to different sTTI lengths; sPDCCH corresponding to different sTTI lengths The detection positions are the same but the demodulation is attempted separately according to the respective pilot patterns of different sTTI lengths in different rate matching manners.

Mode 2: Try blind detection without distinguishing between different sTTI lengths. The method includes: the sPDCCH detection positions corresponding to different sTTI lengths are the same, and the pilots in the same position according to the same position in the sPDCCH region try to demodulate in the same rate matching manner.

Whether the specific sPDCCH blind detection needs to be blindly detected with different sTTI lengths is mainly a DMRS-based demodulation problem, and CRS-based demodulation does not exist.

When the sTTI length is known, if the slow DCI informs the sTTI length of the subframe, the sPDCCH blind detection only needs to follow the DMRS in the specific sTTI. When the sTTI length is known, the blind detection of the sPDCCH has no problem.

When the sTTI length is not known, that is, the sPDCCH is sPDCCH, the s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s (The DL sTTI only supports 2 or 7 symbols, the problem is mainly concentrated at the beginning of the second slot, assuming that the sPDCCH is located in the first OFDM symbol in the sTTI):

Method 1: blind detection

When sTTI=2 symbols, OFDM symbol #6 is detected in DL sTTI#3, and DMRS RE is de-rate matched according to sTTI=2 symbol; OFDM symbol #7 is detected when sTTI=7 symbol, demodulated according to DMRS located at symbols #9 and 10. At this time, it is assumed that there is no DMRS in symbol #7.

At this time, the DMRS design assumes that when sTTI=7, the DMRS is located at

symbols

2, 3 and symbols 9, 10; when sTTI=2, the DMRS is located at both symbols. The DMRS defaults to one RE in the frequency domain and occupies 3 REs.

Method 2: Unified blind inspection

Both the sTTI=2 symbol and the sTTI=7 symbol blindly check the sPDCCH in OFDM symbol #7, and rate-matching is performed in the same manner. The DMRS has the same DMRS RE position in OFDM symbol #7 for sTTI=2 symbols and sTTI=7 symbols.

At this time, the DMRS design assumption is: when sTTI=7, the DMRS is at least at symbol 7; sTTI=2 At the same time, the DMRS is located on both symbols at the same time. The DMRS defaults to one RE in the frequency domain and occupies 3 REs.

Remark: The other sTTI=2 is blinded according to the first OFDM symbol in the sTTI (except for the legacy PDCCH region). When sTTI=7, it is blindly detected in the legacy PDCCH in the first slot.

As a preferred implementation manner, when the DCI supports scheduling a different TTI length and supporting a traffic channel with reduced delay, the DCI usage mode includes at least one of the following:

Mode 1: The TTI=TTI=2 OFDM symbols, TTI=1 slots (for example, 7 OFDM symbols), 1 ms TTI (for example, 14 OFDM symbols) delay reduction, and 1 ms TTI delay are not reduced. The DCI format, that is, also includes whether the delay is reduced at 1 ms TTI.

Mode 2: 1 ms TTI delay reduction and 1 ms TTI delay does not decrease using the same DCI format, TTI = 2 OFDM symbols and TTI = 1 slot (eg 7 OFDM symbols) using another DCI format or two levels DCI, the above two DCI formats are different from each other.

Mode 3: 1 ms TTI delay does not decrease using a DCI format, TTI = 2 OFDM symbols, TTI = 1 slot (eg, 7 OFDM symbols), and 1 ms TTI (eg, 14 OFDM symbols) delay reduction uses another A DCI format or two-level DCI, the above two DCI formats are different from each other.

Mode 4: 1 ms TTI delay is reduced, 1 ms TTI delay is not reduced, and TTI = 1 slot (for example, 7 OFDM symbols) uses the same DCI format, TTI = 2 OFDM symbols use another DCI format or two Level DCI, the above two DCI formats are different from each other.

Mode 5: 1 ms TTI delay does not decrease using one DCI format, 1 ms TTI delay is reduced using another DCI format, TTI = 2 OFDM symbols and TTI = 1 slot (for example, 7 OFDM symbols) The DCI format or the two-level DCI, the above three DCI formats are different from each other.

Mode 6: 1 ms TTI delay does not decrease using one DCI format, 1 ms TTI delay reduction and TTI = 1 slot (for example, 7 OFDM symbols) use another DCI format, TTI = 2 OFDM symbols use one more Kind of DCI format or two-level DCI, the above three DCI formats are not mutually the same.

Specifically, the mode 1 is equivalent to a unified design, that is, the UE supporting the reduced delay at this time uses a DCI. Alt.1 is based on the existing format 0/1A, adds the bit field, and uses RRC to configure the TTI length. Alt.2 is based on the newly designed DCI format, which uses the TTI length indication, single-level DCI or slow DCI. Advantages: Unified DCI design. Disadvantages: alt.1 does not support dynamic scheduling of PDSCH and sPDSCH. Alt.2 is necessary for the single-level DCI except that the first sTTI in the subframe has a TTI length indication, and the other sTTI indications are useless. If the new DCI includes an sPDCCH resource indicating that it is not used, the DCI is not properly loaded with the PDCCH channel. Therefore, for mode 1, it is more suitable for two-level DCI, and the slow DCI supports different length TTIs and is carried by the PDCCH. At this time, the sPDCCH carries the fast DCI. For TTI=14, the slow DCI contains complete scheduling information.

When the TTI length is not known when detecting fast DCI or single-level DCI, it can be semi-statically configured through high-level signaling, or DCI can be blindly checked according to different TTI lengths, one or two in the same way as G. Moreover, when the TTI length is not indicated in the DCI, the other bit fields corresponding to different TTI lengths are all the same at this time.

Modes 2 through 4 consider both DCIs. Modes 2 and 4 can be regarded as distinguishing two different DCIs from the perspective of TTI length. Mode 3 distinguishes two different DCIs from the perspective of whether the delay is reduced. Benefits of Mode 2: The 1 ms TTI delay is treated differently from the sTTI, that is, the 1 ms TTI delay is reduced and the 1 ms TTI delay is not reduced. The same DCI is used, and the legacy DCI is used as much as possible or slightly modified. The sTTI DCI design has large variables, such as two-level DCI, indicating unused sPDCCH resources. The benefit of mode 4: For sTTI=7 symbols, it is indeed contradictory. On the one hand, the existing protocol indicating the scheduling of the slot level can already be supported, that is, sTTI=7 and TTI=14 are not substantially different. On the other hand, sTTI=7 has been discussed together with sTTI=2, that is, both are also suitable for using the same DCI. So way 4 is another possibility. Reason 3: The 1 ms delay does not reduce the use of the existing legacy DCI, and the rest of the delay reduction can use common features such as asynchronous UL HARQ.

Modes

5 and 6 consider three DCIs, that is, the 1 ms TTI delay does not decrease. The legacy DCI separates two possible cases for the 1 ms TTI delay reduction and whether the sTTI uses the same DCI and the sTTI=7 symbol. However, distinguishing too many DCI formats adds complexity to UE blind detection.

When the 1 ms TTI delay is reduced and the same DCI format is used for the 1 ms TTI existing delay, the following possible ways are included: 1. Use the existing DCI without modification. When the PHICH is still used to feed back ACK/NACK to the PUSCH, the 1 ms delay reduction is implicitly determined by the TBS. 2. Add a new bit field directly. It may be new DCI format, or it may be modified directly in format 0 or 4 to increase the bit field. It is possible to add a UL HARQ process number, RV (asynchronous HARQ) in Format 0/4, and a timing k indication may be added in format 0 or 4 or 1A. Affects format 1A to increase padding. The sTTI DCI can also be supported when a new bit field is added at this time. At this time, when the 1 ms TTI delay does not decrease, the newly added bit field can be reserved. Alternatively, when there is a k indication, the respective bit fields can be defined separately. 3. Currently DCI bit field reuse. When the PHICH is not used, the UL grant needs to add the UL HARQ process number, RV, and the reinterpreted bit field is used when implicitly performing a 1 ms delay reduction according to the RRC configuration according to the TBS or display or according to different C-RNTI scrambling.

When the 1 ms TTI delay is reduced to use the same DCI format as the sTTI, the following possible modes are included: 1. When the TTI length indicating bit field exists in the DCI, the remaining bit fields of different TTI lengths may be separately designed. When the DCI is a single-level DCI, the bit field mainly functions in the first sTTI or legacy PDCCH region. When the DCI is two-level DCI, the bit field is located in the slow DCI, and for TTI=1ms and or TTI=7 symbols, the slow DCI contains complete scheduling information. 2. When there is no TTI length indication bit field in the DCI, the remaining bit fields of different TTI lengths need to be uniformly designed. In this case, the TTI length can be semi-statically configured by the high layer signaling or a fixed value. When there is no TTI length bit field in the downlink DCI in the two-stage DCI, the resource allocation field is applicable to all TTI lengths at this time, and when the scheduling sTTI=2 or 7 or UL sTTI=4 symbols, the subsequent undesired bit field reserved Or partially used to reinterpret the indication of fast DCI resources; for scheduling TTI = 14 or 7 symbols, all required bit fields are used.

Corresponding to the transmission method of the downlink control information, in this embodiment, a The transmission device of the line control information is located in the base station, and the device is used to implement the above-mentioned embodiments and preferred embodiments, and has not been described again. As used below, the term "module" may implement a combination of software and/or hardware of a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware, is also possible and contemplated.

FIG. 3 is a structural block diagram of a transmission apparatus for downlink control information according to an embodiment of the present disclosure. As shown in FIG. 3, the apparatus includes:

The bearer module 22 is configured to carry downlink control information DCI of the terminal UE for scheduling the short transmission time interval sTTI by using at least one of a legacy physical downlink control channel (legacy PDCCH), an enhanced physical downlink control channel (ePDCCH), and an sPDCCH. The sPDCCH is a physical downlink control channel in the sTTI; the sending module 24 is connected to the bearer module 22, and is configured to send the DCI carried by the bearer module 22 to the terminal; where the DCI is used for scheduling the traffic channel, including at least the following One: only the traffic channel in the sTTI; the traffic channel in the sTTI or the traffic channel in the 1 ms TTI; the traffic channel in the sTTI and the traffic channel in the 1 ms TTI.

Optionally, the apparatus may further include a notification module, configured to use one of the foregoing two manners by using the high layer signaling RRC or the SIB notification or to use one of the foregoing two methods.

Optionally, the apparatus may further include: a configuration module, configured to configure an update period of the first-level DCI in the two-level DCI by using high-level signaling SIB or RRC. This method can be applied to the case where the fast DCI has complete scheduling information. When a slow DCI demodulation error occurs, but is still within the update period range, the previous slow DCI indication is used to reduce the fast DCI demodulation complexity.

As a preferred embodiment, in a case where the sPDCCH is based on DMRS demodulation, the apparatus may further include a port selection module configured to select to use a corresponding sPDSCH port according to a port usage principle.

Specifically, when the DMRS is shared with the sPDSCH of the local UE, the sPDSCH port usage principle includes at least one of the following:

Use DMRS with the same port as sPDCCH when RI=1;

When RI=2, the same port as the RE location of the DMRS of the sPDCCH is used;

The sPDSCH port is indicated by the DCI in combination with the sPDCCH transmission mode. For example, the sPDSCH port may be not indicated when the sPDSCH is used in the DCI, or the same port as the RE where the sPDCCH is used by the sPDCCH, and the sPDCCH uses port x1, sPDSCH. Also use port x1, or use port x2 with the same RE location as port x1. The sPDSCH layer 2 transmission may not indicate, and the corresponding port is used according to the sPDCCH transmission mode. When the sPDCCH transmission mode uses the port x1, the sPDSCH uses the port x1 and x2 of the same RE position as the port x1, and the port x1 and y1 are used when the sPDCCH transmission mode is used. When the sPDSCH uses port x1, x2 of the same RE location as port x1, or port y1, y2 of the same RE location as port y1, or uses port x1, y1 (preferred), or indicates a port corresponding to the sPDCCH transmission mode, when When port x1 is used for the sPDCCH transmission method, the sPDSCH is instructed to use the ports x1 and x2 of the same RE position as the port x1, and when the sPDCCH transmission mode uses the ports x1 and y1, the sPDSCH uses the port x1, x2 of the same RE position as the port x1, or Port y1 port y1, y2 at the same RE position, or port x1, y1 (preferred). When the sPDSCH uses more than Layer 2 transmission, it may not indicate that the corresponding port is used according to the transmission mode. When the sPDCCH transmission mode uses port x1, the sPDSCH uses the port x1, x2, x3, ... of the same RE position as the port x1, when the sPDCCH is transmitted. When port x1 and y1 are used, sPDSCH uses port x1, x2, x3, ... at the same RE position as port x1, or port y1, y2, y3, ... at the same RE position as port y1, or uses port x1, y1, x2. Y2, ... (preferably), or port x1, x2, x3, ... indicating that the sPDSCH uses the same RE position as the port x1, and when the sPDCCH transmission mode uses the ports x1, y1, the sPDSCH uses the port x1, x2 of the same RE position as the port x1 , x3..., or port y1, y2, y3... at the same RE position as port y1, or using ports x1, y1, x2, y2, ... (preferred);

Optionally, the apparatus may further include a scrambling module configured to scramble the sPDCCH. The scrambling initialization method of the sPDCCH is that each sTTI in the subframe or the radio frame is independently scrambled, wherein the sPDCCH scrambling initialization in the first sTTI or the legacy PDCCH region in the subframe satisfies

c _init is the scrambling initialization value, n _s is the slot number,

It is the identification (ID) number of the cell.

It should be noted that each of the above modules may be implemented by software or hardware. For the latter, the foregoing may be implemented by, but not limited to, the foregoing modules are all located in the same processor; or, the above modules are in any combination. The forms are located in different processors.

In this embodiment, another method for transmitting downlink control information is further provided. FIG. 4 is a flowchart of another method for transmitting downlink control information according to an embodiment of the present disclosure. As shown in FIG. 4, the method includes The following steps:

Step S302, receiving downlink control information (DCI) of a terminal (UE) for scheduling a short transmission time interval (sTTI) carried by at least one of a legacy physical downlink control channel legacy PDCCH, an enhanced physical downlink control channel ePDCCH, and an sPDCCH, The sPDCCH is a physical downlink control channel in an sTTI;

Step S304, the UE uses the DCI to perform scheduling.

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.

In this embodiment, the DCI of the UE for scheduling the sTTI is carried in at least one of the legacy PDCCH, the ePDCCH, and the sPDCCH, and the UE uses the DCI to perform scheduling, which solves the short support in the low-latency communication scenario in the related art. The problem of downlink control information for TTI and its related service scheduling is given to support short TTI scheduling and its associated different length TTIs. The implementation of the service scheduling ensures the delay communication requirements.

B. The DCI of the UE for scheduling the sTTI and the DCI for scheduling the 1 ms PDSCH are located in different search spaces. It can be distinguished by restricting the search space in which the DCIs of different service channels are scheduled, for example, respectively located in CSS or USS, respectively in the Legacy search space and the newly defined search space. Preferably, it can be used to schedule only the traffic channel in the sTTI; schedule the traffic channel in the sTTI or the traffic channel in the 1 ms TTI; schedule the traffic channel in the sTTI and the traffic channel in the 1 ms TTI.

C. Differentiate the DCI of the UE for scheduling the sTTI by using the indication identifier in the first-level DCI or the first-level DCI of the two-level DCI to schedule the traffic channel in the 1 ms TTI or to schedule the traffic channel in the sTTI. The method is preferably used to schedule a traffic channel in an sTTI or a traffic channel in a 1 ms TTI.

Indicating a transmission mode of the sPDSCH;

Indicates whether the sPDCCH and/or sPDSCH carrying the second-level DCI is demodulated based on CRS Use DMRS;

When the second level of the two-level DCI includes complete scheduling information, the second-level DCI includes resource allocation;

Indicating sPDSCH and/or sPUSCH resource allocation information;

Indicates the PRB location of the DMRS used for sPDSCH demodulation;

Indicates the number of DL sTTI bundling transmissions and/or UL sTTI bindings (bundling) The number of transmissions.

Use DMRS with the same port as sPDCCH when RI=1;

When RI=2, the same port as the RE location of the DMRS of the sPDCCH is used;

The sPDSCH port is indicated by the DCI in combination with the sPDCCH transmission mode. For example, the sPDSCH port may be not indicated when the sPDSCH is used in the DCI, or the same port as the RE where the sPDCCH is used by the sPDCCH, and the sPDCCH uses port x1, sPDSCH. Also use port x1, or use port x2 with the same RE location as port x1. The sPDSCH layer 2 transmission may not indicate, and the corresponding port is used according to the sPDCCH transmission mode. When the sPDCCH transmission mode uses the port x1, the sPDSCH uses the port x1 and x2 of the same RE position as the port x1, and the port x1 and y1 are used when the sPDCCH transmission mode is used. When the sPDSCH uses port x1, x2 of the same RE location as port x1, or port y1, y2 of the same RE location as port y1, or uses port x1, y1 (preferred), or indicates a port corresponding to the sPDCCH transmission mode, when When port x1 is used for the sPDCCH transmission method, the sPDSCH is instructed to use the ports x1 and x2 of the same RE position as the port x1, and when the sPDCCH transmission mode uses the ports x1 and y1, the sPDSCH uses the port x1, x2 of the same RE position as the port x1, or Port y1 port y1, y2 at the same RE position, or port x1, y1 (preferred). When the sPDSCH uses more than Layer 2 transmission, it may not indicate that the corresponding port is used according to the transmission mode. When the sPDCCH transmission mode uses port x1, the sPDSCH uses the same RE location as the port x1. Port x1, x2, x3, ..., when port x1, y1 is used for the sPDCCH transmission mode, sPDSCH uses port x1, x2, x3, ... of the same RE position as port x1, or port y1, y2 of the same RE position as port y1 Y3..., or use port x1, y1, x2, y2, ... (preferred), or port x1, x2, x3, ... indicating that sPDSCH uses the same RE position as port x1, and sPDSCH when port s1, y1 is used for sPDCCH transmission mode Use port x1, x2, x3, ... at the same RE position as port x1, or port y1, y2, y3, ... at the same RE position as port y1, or use port x1, y1, x2, y2, ... (preferred);

Optionally, when the DMRS frequency domain location shared by the sPDCCH and the sPDSCH is located in a part of the PRB, at least one of the following occupation modes is included:

Only in the PRB where the sPDCCH is located;

At least in the PRB where the sPDCCH is located;

c _init is the scrambling initialization value, n _s is the slot number,

It is the identification (ID) number of the cell.

Corresponding to the transmission method of the other downlink control information, in the embodiment, another downlink control information transmission device is further provided, which is located in the UE, and the device is used to implement the foregoing embodiment and the preferred embodiment, and has been performed. The description will not be repeated.

FIG. 5 is a structural block diagram of another apparatus for transmitting downlink control information according to an embodiment of the present disclosure. As shown in FIG. 5, the apparatus includes:

The receiving module 42 is configured to receive downlink control information of a UE for scheduling a short transmission time interval (sTTI) carried by at least one of a legacy physical downlink control channel (legacy PDCCH), an enhanced physical downlink control channel (ePDCCH), and an sPDCCH. (DCI), the sPDCCH is a physical downlink control channel in the sTTI, and the scheduling module 44 is configured to perform scheduling by using the DCI received by the receiving module 42. The traffic channel used by the DCI for scheduling includes at least one of the following: : only the traffic channel in the sTTI; the traffic channel in the sTTI or the traffic channel in the 1 ms TTI; the traffic channel in the sTTI and the traffic channel in the 1 ms TTI.

Optionally, the apparatus may further include an obtaining module, configured to obtain, by using the high layer signaling RRC or the SIB, one of the foregoing two methods or one of the foregoing two methods.

Optionally, the acquiring module may be further configured to acquire an update period of the first-level DCI in the two-level DCI configured by the high-layer signaling SIB or RRC. This method can be applied to the case where the fast DCI has complete scheduling information. When a slow DCI demodulation error occurs, but is still within the update period range, the previous slow DCI indication is used to reduce the fast DCI demodulation complexity.

Use DMRS with the same port as sPDCCH when RI=1;

When RI=2, the same port as the RE location of the DMRS of the sPDCCH is used;

c _init is the scrambling initialization value, n _s is the slot number,

It is the identification (ID) number of the cell.

In this embodiment, a transmission system for downlink control information is also provided. FIG. 6 is a structural block diagram of a transmission system for downlink control information according to an embodiment of the present disclosure. As shown in FIG. 6, the device includes the same as shown in FIG. The transmission device 30 located in the downlink control information of the base station further includes a transmission device 40 located in the downlink control information of the UE as shown in FIG. 5.

By using the transmission scheme of the downlink control information proposed in this embodiment, the problem of designing downlink control information in short TTIs with fewer OFDM symbols can be solved, short TTI scheduling and scheduling services of different lengths of TTIs are supported, and low-latency communication requirements are ensured. .

The following description is made in conjunction with the preferred embodiments, and the following preferred embodiments incorporate the above-described embodiments and preferred embodiments thereof.

In the following preferred embodiments, a downlink control information transmission scheme is provided: the base station carries the downlink control information of the scheduled sTTI UE by using at least one of the legacy PDCCH and the sPDCCH, and sends the downlink control information to the terminal.

The traffic channel scheduled by the downlink control information includes at least one of the following:

Used only to schedule traffic channels in sTTI;

Used to schedule a traffic channel in a sTTI or a traffic channel in a 1 ms TTI;

It is used to schedule the traffic channel in the sTTI and the traffic channel in the 1ms TTI.

The Legacy PDCCH is a physical downlink control channel in the LTE system, and includes a PDCCH, an ePDCCH, an rPDCCH, and the like. The sPDCCH indicates a physical downlink control channel in the sTTI, which may be simply referred to as a sPDCCH (Short PDCCH), and similarly, a physical downlink traffic channel in the sTTI. It can be abbreviated as sPDSCH (Short PDSCH), and the physical uplink traffic channel in sTTI can be simply referred to as sPUSCH (Short PUSCH). The sTTI is a TTI that is less than 1 ms in time. For the LTE system, the short TTI is composed of N OFDM symbols, and the number N of OFDM symbols included is {1, 2, 3, 4, 5, 6, 7}. At least one of them. Wherein, if the sTTI includes N OFDM symbols, the sPDCCH occupies X OFDM symbols in the time domain, X≤N, and X preferably takes a value of 1 or 2. And X OFDM symbols are located in the first X OFDM symbols among the N OFDM symbols of the sTTI. The value of X can be fixed or configured by the base station. The sPDCCH is located in a subframe or a partial resource position in an OFDM symbol or an OFDM symbol, and the partial resource is a partial PRB or REG resource in one or more OFDM symbols in a subframe or an sTTI, or a partial resource is a partial PRB or REG resource in the OFDM symbol. Further, the resource unit in the frequency domain may also use the PRB aggregation and use or configure the N PRBs as a group; similar REGs may also be used for aggregation.

The downlink control information includes at least one of a legacy DCI in the LTE system and a newly designed sTTI DCI in the sTTI UE. When the downlink control information is used only for scheduling the traffic channel in the sTTI, the legacy PDCCH carries the 1 ms TTI traffic channel of the legacy DCI scheduling sTTI UE, and the legacy channel is carried by the legacy PDCCH or the sPDCCH carrying the sTTI DCI; the downlink control information is used for The traffic channel in the sTTI or the traffic channel in the 1 ms TTI is scheduled by the Legacy PDCCH or the sPDCCH carrying the sTTI DCI when the traffic channel in the sTTI or the traffic channel in the 1 ms TTI is scheduled. The downlink control information is used to schedule the traffic channel in the sTTI and the traffic in the 1 ms TTI. In the case of the channel, the Legacy DCI carries the 1 ms TTI traffic channel of the sTTI UE, and the sPDCCH carries the sTTI DCI to schedule the traffic channel in the sTTI;

Further, when the DCI is used to schedule a traffic channel in a sTTI or a traffic channel in a 1 ms TTI, in the first level of the first-level DCI or the two-level DCI, the indication bit field is used to distinguish whether the service channel in the 1 ms TTI is scheduled. Traffic channel in sTTI.

Specifically, the sTTI DCI includes a function of scheduling sTTI or 1 ms TTI. When using single-level In the DCI, whether the 1ms TTI or the sTTI traffic channel is scheduled is indicated by the sTTI/TTI flag bit field. The sPDCCH is used to carry the sTTI DCI and simultaneously supports 1 ms TTI and sTTI dynamic scheduling. Optionally, the sTTI/TTI flag is useless in the non-first sTTI in the subframe, or the sTTI/TTI flag is used to indicate other functions in the non-first sTTI. When a two-level DCI is used, the first-level DCI (also referred to as a slow DCI) indicates whether to schedule a 1 ms TTI or an sTTI traffic channel by using the sTTI/TTI flag, and may be a legacy PDCCH or an sPDCCH bearer for the slow DCI. The use of the sTTI/TTI flag indication is shown in Table 1, where the cases indicated by flag=0 and flag=1 are also interchangeable. At this time, only one PDSCH or sPDSCH is scheduled to be supported in one subframe of the same carrier, and the detection complexity is low, and the terminal processing is simple. For the case of indicating the sTTI scheduling, the sTTI extracted per subframe scheduling information may include DL and/or UL scheduling information, such as the sTTI band resource allocation (the resource allocation refers to the resource indication on the frequency domain, preferably indicating the system bandwidth) Which PRB resources are occupied) may be DL sTTI band resource allocation and/or UL sTTI band resource allocation, sTTI length may be DL sTTI length and/or UL sTTI length, fast DCI resource indication (fast DCI resource indication refers to sPDCCH carrying fast DCI) The parameter indication required for detection) may be a DL fast DCI resource indication and/or a UL fast DCI resource indication.

Table 1sTTI/TTI flag indication

Or, when the DCI is used to schedule a traffic channel in a sTTI or a traffic channel in a 1 ms TTI, whether the service channel in the 1 ms TTI is scheduled by using the indication bit field in the first level of the first-level DCI or the two-level DCI Traffic channel in sTTI. At this time, the identifier bit field is not only 1 bit indicating 1 ms TTI and sTTI, but also 2 bits indicating sTTI of different granularity, such as using 2 bits. Indicates 1 ms TTI, 2 OFDM symbol sTTI, 7 OFDM symbol sTTI, 4-3-4-3 OFDM symbol sTTI (indicating that the OFDM symbol in the normal CP at the time of the sub-frame is divided into 4 sTTIs, respectively having 4-3-4-3 OFDM symbol, when Extended CP, this structure is 3-3-3-3 OFDM symbol).

Further, the downlink control information is a first-level DCI or a two-level DCI, where the traffic channel scheduling information indicated by the two-level DCI includes at least one of the following:

The first level and the second level of the two-level DCI together form complete scheduling information;

The second level of the two-level DCI includes complete scheduling information. In this case, the first level optionally includes but is not limited to at least one of the following: partial scheduling information, indication information of the second-level DCI, frequency domain range of the sTTI, and downlink. (DL) length of sTTI, length of uplink (UL) sTTI, frequency domain range of DL sTTI bandwidth, frequency domain range of UL sTTI band;

Specifically, when the downlink control information is the first-level DCI, each DCI can independently schedule the corresponding traffic channel, and has complete scheduling information. In the case that no base station configuration detects the sTTI time, the default is required in each sTTI. The DCI is detected. When the downlink control information is two-level DCI, the two-stage DCI indicates that the traffic channel scheduling information is that the first level and the second level of the two-level DCI form a complete scheduling information, and the terminal needs to obtain the information in the two-level DCI to obtain the service. Channel scheduling information. When the downlink control information is two-level DCI, the two-stage DCI indicates that the traffic channel scheduling information is that the second level of the two-level DCI includes complete scheduling information, and the terminal needs to obtain only The information in the second-level DCI can obtain the scheduling information of the traffic channel. At this time, the information in the first-level DCI is the information that assists the second-level DCI detection or the dynamic configuration information of other physical layers. The second-level DCI is also called fast DCI.

Further, the first level DCI includes at least one of the following information:

Determining parameters required for sPDCCH detection carrying a second level DCI, the second level DCI including a second level DCI scheduling sPDSCH and/or sPUSCH, wherein the parameters include an aggregation level, a number of candidate sets, and a search space frequency domain location At least one of a search space time domain location, an sPDCCH scrambling initial value parameter, a DMRS scrambling initial value parameter used by the sPDCCH, an sPDCCH transmission mode, and a DMRS port used for sPDCCH demodulation; specifically, indicating that the aggregation level is sPDCCH supporting all aggregations The partial polymerization level in the rank is preferably one. The number of candidate sets indicated is a partial candidate set of all candidate sets corresponding to each aggregation level, preferably one. The indicated search space frequency domain location is part of the RBG or PRB or REG location in the system bandwidth or sTTI band. The indicated search space time domain location is a partial OFDM symbol position in a subframe or in an sTTI. Instructing the sPDCCH scrambling initial value parameter to be UE-specific

Or group-specific

There is no need to indicate the use of a cell ID for public messages. Indicates that the DMRS scrambling initial value parameter used by the sPDCCH is UE-specific

Or group-specific

There is no need to indicate the use of a cell ID for public messages. The sPDCCH transmission mode is indicated to be at least one of a centralized transmission, a distributed transmission, and a transmit diversity transmission. Indicates the DMRS port used for sPDCCH demodulation, that is, the DMRS port number used by the eNB to directly indicate the second-level DCI demodulation through the first-stage DCI, or indicates the port number combination used.

Indicates a DMRS port or a reserved RE when the sPDCCH and/or the sPDSCH rate of the second-level DCI is matched, where the reserved RE is preferably an RE corresponding to all the DMRS ports, or an RE corresponding to the port occupying the same RE; When the sPDCCH and the sPDSCH use the DMRS in the region with the overlapping frequency domain locations, the first-level DCI indicates the DMRS port when the sPDCCH and/or the sPDSCH rate of the second-level DCI is matched, so that the sPDCCH carrying the second-level DCI is used. And/or the sPDSCH can know the DMRS pilot that does not need to be demodulated but exists in the rate matching in the frequency domain overlapping region, so that the eNB and the terminal match at the rate. Understand the same.

Indicating that the sPDCCH and/or sPDSCH demodulation carrying the second-level DCI uses the pilot CRS and/or DMRS; specifically, the first-stage DCI indicates that the sPDCCH and/or sPDSCH demodulation using the second-level DCI uses the pilot as a CRS or DMRS, or both CRS and DMRS.

Indicates a transmission mode of the sPDSCH; specifically, the first-level DCI indicates an sPDSCH transmission mode in the subframe.

Indicates whether the sPDCCH and/or the sPDSCH carrying the second-level DCI is used based on CRS demodulation; specifically, the first-level DCI indicates whether the sPDCCH and/or the sPDSCH carrying the second-level DCI is used based on CRS demodulation.

Indicates whether the CRS is used when the sPDCCH and/or the sPDSCH carrying the second-level DCI is demodulated based on the DMRS; specifically, the first-level DCI indicates whether the sPDCCH and/or the sPDSCH carrying the second-level DCI is used based on the DMRS demodulation.

Indicates the PRB location of the DMRS used when demodulating the sPDCCH and/or sPDSCH carrying the second-level DCI. Specifically, the first-level DCI indicates the PRB location of the DMRS used when the sPDCCH and/or sPDSCH carrying the second-level DCI is demodulated.

Indicating a downlink DL sTTI bandwidth frequency domain location and/or an uplink UL sTTI bandwidth frequency domain location;

For the indications referred to above, when the first level DCI is non UE-specific signaling, the sPDCCH and or sPDSCH related parameters for non UE-specific are indicated. When the first level DCI is UE-specific signaling, the sPDCCH and or sPDSCH related parameters for UE-specific are indicated.

Further, when the first-level DCI indicates a parameter required for detecting the sPDCCH of the second-level DCI, indicating the RRC or SIB configuration based on the parameters of the RRC or SIB configuration. A subset of the parameters. The subset may include a subset of the parameter categories, and/or a subset of the parameter value ranges. Specifically, parameters required for sPDCCH detection of the second-level DCI are still configured by higher layer signaling (SIB or RRC signaling), where the parameters include an aggregation level, a number of candidate sets, a search space frequency domain location, and a search space time domain. At least one of a location, an sPDCCH scrambling initial value parameter, a DMRS scrambling initial value parameter used by the sPDCCH, an sPDCCH transmission mode, and a DMRS port used for sPDCCH demodulation, where the first level DCI is based on a high layer signaling SIB or an RRC indication parameter Indicates a reduced or specific parameter, ie, a subset indicating a high layer signaling SIB or RRC indication parameter, the subset including a subset of the parameter categories, and or a subset of the parameter value ranges. If one or a few are indicated in the configured aggregation level set, one type is indicated in the configured candidate set, and the reduced or specific frequency domain location is indicated in the configured search space frequency domain location. The configured search space time domain location indicates a reduced or specific time domain location.

Further, the second level DCI includes at least one of the following information:

When the two-level DCI is configured to form the complete scheduling information, the second-level DCI includes the resource allocation and is indicated on the basis of the resource allocation in the first-level DCI; specifically, the sTTI frequency domain in the current subframe indicated by the first-level DCI Based on the location range R, the second-level DCI indicates that the UE supports all or part of the resources in the resource R allocated by the first-level DCI. For example, 3 bits are used to indicate that resources occupying {1, 1/2, 1/4} R, that is, 7 possibilities, wherein 1/2R and 1/4R can occupy occupied resources at equal intervals or at equal intervals.

Indicating sPDSCH and/or sPUSCH resource allocation information;

Indicates the PRB location of the DMRS used when sPDSCH demodulation.

Indicates the DMRS port when the sPDSCH rate matches; specifically, when sPDCCH and When the sPDSCH uses the DMRS in the area with the overlapping frequency domain position, the second-level DCI indicates the DMRS port when the sPDSCH rate matches, so that the sPDSCH can know the DMRS that does not need to be demodulated but exists in the rate matching in the frequency domain overlapping area. The pilots make the eNB and the terminal understand the consistency in rate matching.

Indicates the PRB location of the DMRS used when sPDSCH demodulation. Specifically, the second-level DCI indicates the PRB location of the DMRS used when the sPDSCH is demodulated.

Indicates a downlink DL sTTI bandwidth frequency domain location and/or an uplink UL sTTI bandwidth frequency domain location.

Indicates the length of the DL sTTI and/or the length of the UL sTTI.

Indicates the number of DL sTTI binding transmissions and/or the number of UL sTTI binding transmissions.

Further, an update period of the first-level DCI (also referred to as a slow DCI) in the two-stage DCI is configured by higher layer signaling (SIB or RRC). Specifically, when the second-level DCI (also called fast DCI) has complete scheduling information, when a slow DCI demodulation error occurs, but is still within the update period range, the previous slow DCI indication is used to lower the fast DCI demodulation complexity. Preferably, the update period is at least one of 1 ms, 4 ms, 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, 160 ms, 320 ms.

Further, when the sPDCCH is demodulated based on DMRS:

Use DMRS with the same port as sPDCCH when RI=1;

When RI=2, the same port as the RE location of the DMRS of the sPDCCH is used;

The sPDSCH port may be indicated by the DCI in combination with the sPDCCH transmission mode. For example, the sPDSCH port may be used when the sPDSCH port is used in the DCI, or the same port as the RE where the sPDCCH is used, and the sPDCCH port is used. X1, sPDSCH also uses port x1, or port x2 with the same RE position as port x1. The sPDSCH layer 2 transmission may not indicate, and the corresponding port is used according to the sPDCCH transmission mode. When the sPDCCH transmission mode uses the port x1, the sPDSCH uses the port x1 and x2 of the same RE position as the port x1, and the port x1 and y1 are used when the sPDCCH transmission mode is used. When the sPDSCH uses port x1, x2 of the same RE location as port x1, or port y1, y2 of the same RE location as port y1, or uses port x1, y1 (preferred), or indicates a port corresponding to the sPDCCH transmission mode, when When port x1 is used for the sPDCCH transmission method, the sPDSCH is instructed to use the ports x1 and x2 of the same RE position as the port x1, and when the sPDCCH transmission mode uses the ports x1 and y1, the sPDSCH uses the port x1, x2 of the same RE position as the port x1, or Port y1 port y1, y2 at the same RE position, or port x1, y1 (preferred). When the sPDSCH uses more than Layer 2 transmission, it may not indicate that the corresponding port is used according to the transmission mode. When the sPDCCH transmission mode uses port x1, the sPDSCH uses the port x1, x2, x3, ... of the same RE position as the port x1, when the sPDCCH is transmitted. When port x1 and y1 are used, sPDSCH uses port x1, x2, x3, ... at the same RE position as port x1, or port y1, y2, y3, ... at the same RE position as port y1, or uses port x1, y1, x2. Y2, ... (preferably), or port x1, x2, x3, ... indicating that the sPDSCH uses the same RE position as the port x1, and when the sPDCCH transmission mode uses the ports x1, y1, the sPDSCH uses the port x1, x2 of the same RE position as the port x1 , x3..., or port y1, y2, y3... at the same RE position as port y1, or using ports x1, y1, x2, y2, ... (preferred);

Specifically, it is assumed that the sPDCCH uses a DMRS port similar to ePDCCH.

7 is a schematic diagram of an sPDCCH occupying resources only in a portion of an sPRB in a first OFDM symbol in an sTTI according to a preferred embodiment of the present disclosure. As shown in FIG. 7, the sPDCCH is only occupied in a portion of the sPRB in the first OFDM symbol in the sTTI. Resources. It is assumed that PRB#48-49 and 36-37 are occupied by sPDCCH1, and the scheduled sPDSCH1 is located at PRB#44-49, 32-37.

8 is a schematic diagram of a DMRS in a PRB where an sPDCCH is located in need of sharing with an sPDSCH according to a preferred embodiment of the present disclosure, and FIG. 9 is a schematic diagram of a part of a PRB in which a sPDSCH is located without sharing a DMRS with an sPDCCH according to a preferred embodiment of the present disclosure. DMRS in PRB #48-49, 36-37 shown in 8 may need to be shared with sPDSCH (used in sPDSCH) The CRS or sPDSCH does not need to be shared when using the exclusive DMRS. As shown in FIG. 9, the DMRSs in the PRBs #44-47 and 32-35 (if the sPDSCH uses the DMRS) need not be shared with the sPDCCH.

Sharing means that two channels need to use DMRS at the same RE location in CDM mode.

If not shared, the sPDCCH and the sPDSCH each use an independent DMRS RE, which makes the pilot overhead in the sTTI larger.

When sPDSCH uses RI=1, the same port is used;

When sPDCCH is centralized, such as port7, sPDSCH also uses centralized port7.

sPDCCH uses distributed time port 7/9, sPDSCH also uses port7/9;

- Equivalent to PDSCH also increases the way of spatial diversity.

When sPDSCH uses RI=2:

When the sPDCCH is centralized, such as port 7, the sPDSCH layer is the same as the sPDCCH port7, and the port used by the other layer is recommended to select the port 8 of the same RE location;

When sPDCCH is distributed, such as port7/9, the two layers of sPDSCH use port7 and port9 respectively;

- Equivalent to the introduction of restrictions on the second layer port of the PDSCH. The principle is to consider the overhead first, and try to make the DMRS overhead of the sPDSCH not increase based on the DMRS overhead used by the sPDCCH.

When sPDSCH uses RI>2:

When the sPDCCH is centralized, such as port 7, the sPDSCH layer is the same as the sPDCCH port7, and the port used by the other layer is recommended to preferentially select ports 8, 11, and 13 of the same RE location, and then select ports 9, 10, and 12 of different RE locations. 14;

When the sPDCCH is distributed, such as port 7/9, the port of the sPDSCH can be flexibly selected.

- Similar to RI = 2, the use of ports for PDSCH may introduce restrictions when RI > 2. The principle is to consider the overhead first, and try to make the DMRS overhead of the sPDSCH not increase based on the DMRS cost used by the sPDCCH when the RI requirement is met. When the RI requires, the resource location that increases the DMRS overhead is selected.

The port with the same RE location as the DMRS of the sPDCCH is preferentially used, and the port with the RE location of the DMRS of the sPDCCH is used secondly;

Specifically, if the sPDCCH uses the DMRS port 7, the sPDSCH preferentially uses the DMRS ports 8, 11, and 13, and the sub-optimal uses the DMRS ports 9, 10, 12, and 14.

Further, when the DMRS frequency domain location shared by the sPDCCH and the sPDSCH is located in the partial PRB, the method includes at least one of the following manners:

Only in the PRB where the sPDCCH is located; for example, the DMRS of the UE is configured only from the PRB including the sPDCCH, and the demodulation performance for the sPDSCH may be deteriorated at this time. The sPDCCH is preferably distributed in the PRB occupied by the sPDSCH, so that the DMRS is dispersed in the frequency domain as much as possible.

The DMRS of the UE is also configured in the PRB of the PRB where the sPDSCH is located, except for the DMRS in which the PDCCH is located in the PRB.

The PRB is located in the PRB of the intermediate interval of the PDCCH occupied by the sPDCCH or the sPDSCH. For example, the max{sPDCCH occupies the PRB resource, and the sPDSCH occupies the PRB resource}. The interval is x PRBs, where x is a fixed value or a value configured by the eNB through higher layer signaling or physical layer signaling.

The PRB location where the DMRS is located may also be indicated by higher layer signaling or physical layer signaling.

Further, the scrambling initialization method of the sPDCCH is the same as the legacy PDCCH scrambling in the first sTTI in the subframe, and the subsequent sTTI in the subframe is different from the legacy PDCCH scrambling.

Specifically, when the base station side sends the sPDCCH, the initial value determining manner used by the scrambling sequence includes at least one of the following. It should be noted that the following methods (1), (2), and (3) only take the sTTI as two OFDM symbols and the normal CP as an example, and the sTTI number in the subframe is 0 to 6. Also suitable for short TTIs of other lengths. If the sTTI is 7 OFDM symbols, the sTTI sequence number in the subframe is 0 to 1. If the sTTI is 4-3-4-3 OFDM symbols, the sTTI sequence number in the subframe is 0 to 3. The c _init in the following formula is the scrambling initialization value, and n _s is the slot number.

It is the identification (ID) number of the cell.

(1)

n _TTI =0, 1, ..., 6.

(2)

n _TTI =0, 1, ..., 6.

(3)

And when the channel-coded b(i) and c(i) are scrambled, the truncated c-sequence is used. which is

Changed to

Where A is related to at least one of sTTI length, system bandwidth, modulation order, sTTI band width, etc., for example, for sPDCCH, sTTI = 2 OFDM symbols, preferably A = 2400 or 4800.

The scrambling mode is better than the frame-based scrambling randomization method when the sTTI index can be accurately known, and the sPDCCH scrambling in the legacy PDCCH region in the subframe is not added to the PDCCH. Interference conflicts, compatible after implementation.

Further, if the sPDCCH is UE-specific, the C-RNTI or the Group-RNTI is used instead.

Generate a scrambling initial value, or a RRC-configured UE-specific parameter value

The above scheme will be further described in detail below through specific embodiments.

Preferred embodiment 1

(This preferred embodiment 1 implements scheduling PDSCH or sPDSCH through two-level DCI)

The base station schedules the sPDSCH through two-stage DCI. The first-level DCI optionally includes a frequency domain occupied position indicating an sTTI band, and optionally includes an indication sTTI length/pattern. At the same time, the first-level DCI can flexibly schedule 1ms PDSCH and sTTI sPDSCH for the sTTI UE. Preferably, the indication of 1 ms TTI and sTTI scheduling identity is included in the first level of DCI. The first-level DCI is located in the Legacy PDCCH region, or is in the first sTTI, and is carried by the Legacy PDCCH or the sPDCCH.

The first-level DCI (slow DCI) content is exemplified in Table 1, and the downlink traffic channel is scheduled as an example.

Table 1 Format X

If the base station schedules the sPDSCH in the sTTI, the sPDCCH carrying the second-level DCI (fast DCI) is transmitted in the sTTI. The fast DCI content is exemplified in Table 2, and the downlink traffic channel is scheduled as an example. The resource allocation 3 bits indicates that the resources occupying {1, 1/2, 1/4} R, that is, 7 kinds of possibilities, wherein R/2 and R/4 can occupy the resources or occupy the resources at equal intervals. For example, if R is divided into 16 parts, the two types corresponding to R/2 may be a group of even numbers of 16 parts, an odd numbered group; the four types corresponding to R/4 may be 16 parts of the number {0, A group of 4, 8, 12}, a group of numbers {1, 5, 9, 13}, a group of numbers {2, 6, 10, 14}, one of numbers {3, 7, 11, 15} group.

Table 2 Format Y

When receiving the downlink service data, the terminal first demodulates the slow DCI in the Legacy PDCCH region. When demodulating and determining that the PDSCH is scheduled according to the flag, the terminal no longer receives the detected fast DCI, and receives the PDSCH in the detection subframe according to the scheduling information. When it is determined by the flag that the sTTI sPDSCH is scheduled according to the flag, the fast DCI carried in the sPDCCH is continuously detected in the sTTI.

The sPDSCH is demodulated in the sTTI according to the information of the scheduled sPDSCH in the demodulation fast DCI.

With the scheme of the embodiment, the first-level DCI in the two-level DCI is added to distinguish the 1ms TTI or the sTTI flag identifier, so that the sTTI terminal performs only one TTI length service channel demodulation in the same subframe, without At the same time, PDSCHs of different TTI lengths are demodulated to reduce the complexity of terminal detection processing. Guaranteed delay requirements.

Preferred embodiment 2

(Two-stage DCI is used in the preferred embodiment 2, and is used independently or independently to indicate fast DCI, transmission mode, pilot, etc.)

The base station schedules the sPDSCH through two-stage DCI. Optionally, the first-level DCI includes a frequency domain occupied position indicating an sTTI band, optionally including an indication sTTI length/pattern, optionally including an sPDSCH transmission mode, and optionally a demodulation pilot including sPDCCH and or sPDSCH. Optionally, the PRB location of the DMRS used by the sPDCCH and or the sPDSCH is optionally included, and optionally includes parameters required for fast DCI related detection. The first-level DCI is located in the Legacy PDCCH region, or is in the first sTTI, and is carried by the Legacy PDCCH or the sPDCCH.

The content of the first-level DCI (slow DCI) is exemplified in Table 3, and the downlink traffic channel is scheduled as an example. The sPDSCH transmission indication may be indicated based on the existing LTE transmission mode (1-10), or may be indicated in the transmission mode set used by the sTTI UE, and the transmission mode set used by the sTTI UE may be only included in the LTE. The transmission mode, or also the newly defined transmission mode for the sTTI UE. The demodulation pilot indication indicates whether the cell reference signal CRS or the UE demodulation reference signal DMRS is based. The PRB location where the DMRS is located is only in the DMRS. Used in each PRB, that is, when there is a DMRS in a part of the PRB, and is not used in a fixed location, indicating that the PRB location where the DMRS is located in the resource allocation area, such as a part of the PRB selected according to the equal interval x (PRB), configures the DMRS. . The Fast DCI detection parameter indication specifically includes an aggregation level, a number of candidate sets, a search space frequency domain location, a search space time domain location, an sPDCCH scrambling initial value parameter, a DMRS scrambling initial value parameter used by the sPDCCH, an sPDCCH transmission mode, and an sPDCCH demodulation. At least one of the DMRS ports used, or a subset of partial parameters (eg, a reduced value or a specific value), based on a higher layer signaling SIB or RRC configuration.

Table 3 Format X

The base station schedules the sPDSCH in the sTTI, and transmits the sPDCCH carrying the second-level DCI (fast DCI) in the sTTI. The fast DCI content is exemplified in Table 4, and the downlink traffic channel is scheduled as an example. When the first level indicates the sTTI resource allocation, the second level DCI indicates further resource allocation, for example, 3 bits indicate that the resources occupying {1, 1/2, 1/4} R, that is, 7 possibilities, where R/2 and R/4 can occupy resources at equal intervals or at discrete intervals. When the second-level DCI is specifically independent of the sPDSCH scheduling information, the resource allocation information of the sPDSCH is directly indicated in the second level.

Table 4 Format Y

When receiving the downlink service data, the terminal first demodulates the slow DCI in the Legacy PDCCH region. When the two-stage DCI together constitutes the complete scheduling information, the terminal demodulates the second-level DCI based on the demodulation of the first-level DCI. Complete sPDSCH demodulation indicator parameters. When the second-level DCI in the two-stage DCI includes complete sPDSCH scheduling information, demodulating the first-level DCI can make the demodulation of the second-level DCI faster and reduce the detection complexity. Otherwise, the second-level DCI detection is not demodulated. When the first-level DCI is obtained, it is detected with a high detection complexity. When the second-level DCI can independently carry the sPDSCH scheduling information, the first-level DCI may not be referred to as DCI, that is, one physical layer signaling, and the detection complexity of the DCI is reduced by the indication.

With the solution of the embodiment, the first-level DCI is added to indicate the second-level DCI-related detection information in the two-level DCI, so that the sTTI terminal obtains the scheduling information with a lower detection complexity when detecting the two-level DCI. The sTTI terminal transmission is flexible based on the subframe level change by adding information indicating the transmission mode of the sPDCCH and or the sPDSCH, demodulation pilot, and the like in the first-stage DCI in the two-stage DCI. Guaranteed delay requirements.

Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware, but in many cases, the former is A better implementation. Based on such understanding, portions of the technical solutions of the present disclosure that contribute substantially or to the prior art may be embodied in the form of a software product stored in a storage medium (eg, ROM/RAM, disk, The optical disc includes a number of instructions for causing a terminal device (which may be a cell phone, a computer, a server, or a network device, etc.) to perform the methods described in various embodiments of the present disclosure.

Example 4

Embodiments of the present disclosure also provide a storage medium. Optionally, in the embodiment, the foregoing storage medium may be configured to store program code for performing the following steps:

Step S102: The downlink control information (DCI) of the terminal (UE) for scheduling a short transmission time interval (sTTI) is carried by at least one of the legacy PDCCH, the ePDCCH, and the sPDCCH, where the legacy PDCCH and the ePDCCH are legacy in the LTE system. PDCCH, ePDCCH, the sPDCCH is a physical downlink control channel in the sTTI;

Step S104, the bearer of the DCI is sent to the terminal.

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.

Optionally, the storage medium is further arranged to store program code for performing the following steps:

Step S302, receiving downlink control information (DCI) of a terminal (UE) for scheduling a short transmission time interval (sTTI) carried by at least one of a legacy PDCCH, an ePDCCH, and an sPDCCH, where the legacy PDCCH and the ePDCCH are in an LTE system. Legacy PDCCH, ePDCCH, the sPDCCH is a physical downlink control channel in the sTTI;

Step S304, the bearer of the DCI is sent to the terminal.

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.

Optionally, in this embodiment, the foregoing storage medium may include, but not limited to, a USB flash drive, a Read-Only Memory (ROM), a Random Access Memory (RAM), a mobile hard disk, and a magnetic memory. Various kinds of programs that can store program code, such as a disc or a disc. quality.

For example, the specific examples in this embodiment may refer to the examples described in the foregoing embodiments and the optional embodiments, and details are not described herein again.

It will be apparent to those skilled in the art that the various modules or steps of the present disclosure described above can be implemented by a general-purpose computing device that can be centralized on a single computing device or distributed across a network of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated as a single integrated circuit module. As such, the disclosure is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present disclosure, and is not intended to limit the disclosure, and various changes and modifications may be made to the present disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and scope of the present disclosure are intended to be included within the scope of the present disclosure.

Industrial applicability

As described above, the method, device, and system for transmitting downlink control information provided by the embodiments of the present invention have the following beneficial effects: the downlink control lacking support for short TTI and related service scheduling in the low latency communication scenario in the related art is solved. The problem of information, the implementation scheme supporting short TTI scheduling and its related different length TTI service scheduling is given to ensure the delay communication requirement.

Claims

A method for transmitting downlink control information includes:

The downlink control information DCI of the terminal UE for scheduling the short transmission time interval sTTI is carried by at least one of the legacy physical downlink control channel legacy PDCCH, the enhanced physical downlink control channel ePDCCH, and the sPDCCH, where the sPDCCH is the physical downlink control channel in the sTTI ;

Transmitting the DCI that is carried to the terminal;

The service channel in which the DCI is used for scheduling includes at least one of the following:

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.
The method of claim 1, wherein when the DCI is used to schedule a traffic channel, at least one of the following is included:

The size of the DCI of the UE for scheduling the sTTI is the same as the DCI size for scheduling the 1 ms PDSCH, and is differentiated by the RNTI, including distinguishing by different values of different types of RNTIs, or by different RNTIs of the same type. Value to distinguish;

The DCI of the UE for scheduling the sTTI and the DCI for scheduling the 1 ms PDSCH are located in different search spaces;

The DCI of the UE for scheduling the sTTI is distinguished by the indication flag in the first-level DCI of the first-level DCI or the two-level DCI for scheduling the traffic channel in the 1 ms TTI or for scheduling the traffic channel in the sTTI.
The method according to claim 2, wherein the message carried by the traffic channel in the 1 ms TTI comprises at least one of the following:

UE unicast message, or cell broadcast message, or a group of UE public messages, Or system change message notification information of a cell level or a group of UEs.
The method according to claim 1, wherein when the downlink control information is two-level DCI, the scheduling information of the traffic channel is indicated by at least one of the following:

The first level and the second level in the two-level DCI together constitute complete scheduling information;

The second level of the two-level DCI contains complete scheduling information.
The method of claim 4, further comprising:

One of the modes is used by the eNB through high layer signaling SIB or RRC notification or one of the modes is predefined.
The method according to claim 4, wherein the first level DCI of the two-level DCI includes at least one of the following information:

Indicates information about parameters required for sPDCCH detection of the second-level DCI, where the second-level DCI includes a second-level DCI that schedules sPDSCH and/or sPUSCH;

Information indicating a DMRS port or a reserved RE when the sPDCCH and/or sPDSCH rate carrying the second-level DCI is matched;

Demodulating the sPDCCH and/or sPDSCH carrying the second-level DCI using information of the pilot CRS and/or DMRS;

Information indicating a transmission mode of the sPDSCH;

Indicates whether the sPDCCH and/or the sPDSCH carrying the second-level DCI is based on whether the DMRS is used when demodulating the CRS;

Indicates whether the sPDCCH and/or the sPDSCH carrying the second-level DCI is based on whether the CRS is used when demodulating the DMRS;

Information indicating a PRB location where the DMRS used for demodulation of the sPDCCH and/or sPDSCH carrying the second-level DCI is located;

Information indicating a downlink DL sTTI bandwidth frequency domain location and/or an uplink UL sTTI bandwidth frequency domain location;

Information indicating the length of the DL sTTI and/or the length of the UL sTTI;

Indicates the number of DL sTTI binding transmissions and/or the number of UL sTTI binding transmissions.
The method according to claim 6, wherein the parameters required for detecting the sPDCCH carrying the second-level DCI include at least one of the following:

Aggregation level, number of candidate sets, search space frequency domain location, search space time domain location, sPDCCH scrambling parameter, DMRS scrambling parameter used by sPDCCH, sPDCCH transmission mode, DMRS port used for sPDCCH demodulation.
The method according to claim 6, wherein when the first-level DCI of the two-level DCI includes information indicating a parameter required for sPDCCH detection of a second-level DCI, the first-level DCI is in RRC or SIB. Based on the configured parameters, a subset of the parameters of the RRC or SIB configuration is indicated, the subset comprising a subset of the parameter categories, and/or a subset of the parameter value ranges.
The method of claim 4, wherein the second level of DCI of the two-level DCI includes at least one of the following information:

When the two levels of DCI together form complete scheduling information, the second level DCI includes information about resource allocation and is indicated on the basis of resource allocation in the first level DCI;

When the second level of the two-level DCI includes complete scheduling information, the second-level DCI includes information about resource allocation;

Indicating sPDSCH and/or sPUSCH resource allocation information;

Information indicating a DMRS port or a reserved RE when the sPDSCH rate matches;

Information indicating the location of the PRB where the DMRS is used for sPDSCH demodulation;

Information indicating the length of the DL sTTI and/or the length of the UL sTTI;

Indicates the number of DL sTTI binding transmissions and/or the number of UL sTTI binding transmissions.
The method of claim 4, wherein an update period of the first level of DCI in the two-level DCI is configured by higher layer signaling SIB or RRC.
The method of claim 1, wherein, in the case that the sPDCCH is based on DMRS demodulation, the method further comprises:

When the DMRS is shared with the sPDSCH of the UE, the usage principle of the sPDSCH port includes at least one of the following:

The DMRS of the same port as the sPDCCH is used when RI=1; the same port as the RE of the DMRS of the sPDCCH is used when RI=2; the same port as the RE of the DMRS of the sPDCCH is preferentially used when RI>2, and then used. a port different from the RE location of the DMRS of the sPDCCH; indicating the sPDSCH port by DCI in combination with the sPDCCH transmission mode;

When the DMRS is shared with the sPDSCH that is not the UE, the sPDSCH port usage principle includes at least one of the following:

The port with the same RE location as the DMRS of the sPDCCH is preferentially used, and the port with the RE location of the DMRS of the sPDCCH is used next.
The method according to claim 11, wherein the DMRS resource location adopts different occupation manners according to whether the sPDCCH and the sPDSCH share the DMRS.
The method of claim 11 wherein said sPDCCH is When the DMRS frequency domain location shared by the sPDSCH is located in a part of the PRB, the DMRS frequency domain location shared by the sPDCCH and the sPDSCH includes at least one of the following:

Only in the PRB where the sPDCCH is located;

At least in the PRB where the sPDCCH is located;

The PRB is located in the PRB of the intermediate interval of the PDCCH occupied by the sPDCCH or the sPDSCH.
The method according to claim 1, wherein the scrambling initialization method of the sPDCCH comprises:

The scrambling initialization method of the sPDCCH is independently scrambled in a subframe or in each sTTI in a radio frame, where the sPDCCH scrambling initialization in the first sTTI or the Legacy PDCCH region in the subframe satisfies
c init is the scrambling initialization value, n s is the slot number,
Is the cell identification number.
The method according to claim 1, wherein when the DCI is used for scheduling a traffic channel in a 1 ms TTI, a scheduling or processing delay of a 1 ms TTI traffic channel with reduced processing delay is supported, and a 1 ms TTI traffic channel is not reduced. Scheduling and scheduling methods include at least one of the following:

The 1ms TTI delay is reduced and the 1ms TTI delay is not reduced. The unified DCI is used. When the content in the DCI is implicitly determined to be less than the preset TBS threshold, the 1ms TTI delay is reduced. Otherwise, the 1ms TTI is executed. The delay does not decrease;

The 1 ms TTI delay is reduced and the 1 ms TTI delay is not reduced. The unified DCI is used, and the independent bit field display in the DCI indicates whether to perform the 1 ms TTI delay reduction;

The 1ms TTI delay is reduced with the 1ms TTI delay without using the respective DCI format.
The method of claim 15 wherein the DCI is scheduled to pass The 1 ms TTI service channel further includes: whether to perform a 1 ms TTI delay reduction by using the high layer signaling SIB or RRC configuration.
The method according to claim 15, wherein when the 1 ms TTI processing delay is decreased, the uplink data scheduling delay or the downlink data feedback delay k satisfies 0<k<4 and is an integer, and the value of k includes At least one of the following:

The eNB and the UE side use the same fixed k value, or the eNB and the UE side respectively use different fixed k values; the downlink and uplink use the same fixed k value, or the downlink and uplink respectively use different fixed k values;

The eNB and the UE side are notified of the same k value by DCI or SIB or RRC, or the eNB and the UE side are notified of different k values by DCI or SIB or RRC; the same k value is notified to the downlink and uplink by DCI or SIB or RRC , or notify the downlink and uplink of different k values through DCI or SIB or RRC.
The method according to claim 1, wherein when the DCI is used to schedule an uplink traffic channel with a 1 ms TTI delay reduction or sTTI, indicating an uplink HARQ process number and/or a redundancy version RV includes at least one of the following manners:

When the 1 ms TTI delay is not lowered, the fixed bit field in the DCI is reinterpreted and then indicated;

Indicated by an independent bit field in the DCI;

The CRC implicit indication is scrambled by different RNTI values.
The method according to claim 1, wherein when the DCI is a single-level DCI or any one-level DCI in a two-level DCI, indicating an unused sPDCCH resource manner includes at least one of the following manners:

When only the sPDCCH scheduling the sPDCCH is included in the sPDSCH frequency domain range Or when there is only one sPDCCH in the search space, by default, other resources except the sPDCCH are allowed to be used in the sPDSCH frequency domain, or 1 bit in the DCI is used to indicate whether the remaining resources in the search space where the sPDCCH is located are allowed to be used;

When there are multiple sPDCCHs in the search space, the candidate set is indicated when the candidate set fills the search space; the unused control channel unit is indicated when the control channel unit fills the search space; in the resource unit group or resource Indicates an unused resource unit group or resource block when the block fills the search space; indicates an unused resource unit when the resource unit fills the search space.
The method of claim 19, wherein the indication corresponding indication range comprises at least one of the following:

Indicates resources that are not used by the sPDCCH in the sPDSCH frequency domain range;

Indicates, in the sTTI band frequency domain range, resources that are not used by the sPDCCH;

Indicates, in the search space SS where the sPDCCH is located, a resource that is not used by the sPDCCH;

Resources that are not used by the sPDCCH are indicated in all SS or sTTI band frequency domain ranges.
The method according to claim 1, wherein the short control channel unit sCCE used by the sPDCCH is composed of a short resource unit group sREG, and the composition manner includes at least one of the following manners:

1 sCCE consists of a fixed number of sREGs;

According to different preset conditions, one sCCE is composed of different numbers of sREGs.
The method according to claim 21, wherein the one sCCE is composed of different numbers of sREGs according to different preset conditions, including:

When there is a cell reference signal CRS, 1sCCE=4sREG;

When there is no CRS, 1sCCE = 3sREG.
The method according to claim 1, wherein when the DCI schedules a traffic channel in the sTTI and the sTTI length is unknown, the manner of detecting the DCI includes at least one of the following:

Performing blind detection according to different sPDCCH detection positions corresponding to different sTTI lengths; sPDCCH detection positions corresponding to different sTTI lengths are the same, but different demodulation attempts are respectively performed according to different pilot patterns in different sTTI lengths;

The sPDCCH detection positions corresponding to different sTTI lengths are the same and the demodulation is attempted in the same rate matching manner according to the pilots in the same position in the sPDCCH region.
The method according to claim 1, wherein when the DCI supports scheduling different TTI lengths and supporting a time delay reduced traffic channel, the DCI is used in at least one of the following manners:

The TCI=2 OFDM symbols, TTI=1 time slots, 1 ms TTI delay reduction, and 1 ms TTI delay are not reduced, all using the same DCI format;

1 ms TTI delay reduction and 1 ms TTI delay does not decrease using one DCI format, using another DCI format or two-level DCI in TTI=2 OFDM symbols and TTI=1 slots;

1 ms TTI delay does not reduce the use of one DCI format, TTI = 2 OFDM symbols, TTI = 1 time slot and 1 ms TTI delay reduces the use of another DCI format or two-level DCI;

1 ms TTI delay is reduced, 1 ms TTI delay is not reduced, and TTI = 1 slot uses one DCI format, TTI = 2 OFDM symbols using another DCI format or two-level DCI;

1ms TTI delay does not decrease using one DCI format, 1ms TTI delay is reduced using another DCI format, TTI=2 OFDM symbols and TTI=1 slots use one more time a DCI format or a two-level DCI;

The 1ms TTI delay does not decrease using one DCI format, the 1ms TTI delay is reduced and the TTI = 1 slot uses another DCI format, and the TTI = 2 OFDM symbols use another DCI format or two-level DCI.
A method for transmitting downlink control information includes:

Receiving downlink control information DCI of a terminal UE for scheduling a short transmission time interval sTTI carried by at least one of a legacy physical downlink control channel legacy PDCCH, an enhanced physical downlink control channel ePDCCH, and an sPDCCH, where the sPDCCH is a physical downlink in the sTTI Control channel

The UE uses the DCI for scheduling;

The service channel in which the DCI is used for scheduling includes at least one of the following:

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.
The method of claim 25, wherein when the DCI is used to schedule a traffic channel, at least one of the following is included:

The size of the DCI of the UE for scheduling the sTTI is the same as the DCI size for scheduling the 1 ms PDSCH, and is differentiated by the RNTI, including distinguishing by different values of different types of RNTIs, or by different RNTIs of the same type. Value to distinguish;

The DCI of the UE for scheduling the sTTI and the DCI for scheduling the 1 ms PDSCH are located in different search spaces;

Is the DCI of the UE for scheduling the sTTI differentiated by the indication flag in the first-level DCI of the first-level DCI or the two-level DCI for scheduling the traffic channel in the 1ms TTI or Used to schedule traffic channels in sTTI.
A transmission device for downlink control information, located at a base station, comprising:

The bearer module is configured to carry, by using at least one of the legacy physical downlink control channel legacy PDCCH, the enhanced physical downlink control channel ePDCCH, and the sPDCCH, the downlink control information DCI of the terminal UE for scheduling the short transmission time interval sTTI, where the sPDCCH is in the sTTI Physical downlink control channel;

a sending module, configured to send the DCI that is carried to the terminal;

The service channel in which the DCI is used for scheduling includes at least one of the following:

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.
A transmission device for downlink control information, located at the terminal UE, includes:

The receiving module is configured to receive downlink control information DCI of the UE for scheduling the short transmission time interval sTTI carried by at least one of the legacy physical downlink control channel legacy PDCCH, the enhanced physical downlink control channel ePDCCH, and the sPDCCH, where the sPDCCH is sTTI Physical downlink control channel;

a scheduling module, configured to use the DCI for scheduling;

The service channel in which the DCI is used for scheduling includes at least one of the following:

Only the traffic channel in the sTTI;

Traffic channel in sTTI or traffic channel in 1ms TTI;

Traffic channel in sTTI and traffic channel in 1ms TTI.
A transmission system for downlink control information, comprising: transmission device for downlink control information according to claim 27, and transmission device for downlink control information according to claim 28.