CN107046716B

CN107046716B - Physical downlink control channel transmission with specific transmission time interval

Info

Publication number: CN107046716B
Application number: CN201610082891.9A
Authority: CN
Inventors: 熊芝兰; 张闽
Original assignee: Nokia Shanghai Bell Co Ltd; Alcatel Lucent SAS
Current assignee: Nokia Shanghai Bell Co Ltd; Alcatel Lucent SAS
Priority date: 2016-02-05
Filing date: 2016-02-05
Publication date: 2020-09-08
Anticipated expiration: 2036-02-05
Also published as: CN107046716A

Abstract

The embodiment of the disclosure provides a method and a device for physical downlink control channel transmission with a specific transmission time interval. The method includes receiving first configuration information specific to a user equipment from a base station via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval. The method also includes searching for a first physical downlink control channel from a potential search region for a current transmission time interval within the current transmission time interval. The embodiment of the disclosure can realize the transmission of the physical downlink control channel with flexible transmission time interval length, and can effectively reduce the control signaling overhead for the data transmission of the short transmission time interval less than 1 millisecond, thereby realizing the reduction of the transmission delay.

Description

Physical downlink control channel transmission with specific transmission time interval

Technical Field

Embodiments of the present disclosure generally relate to the field of wireless communications, and in particular, to a method and apparatus for physical downlink control channel transmission with a specific transmission time interval.

Background

In existing Long Term Evolution (LTE) and/or long term evolution-advanced (LTE-a) systems, the Transmission Time Interval (TTI) for data transmission is typically 1 millisecond (ms). However, more and more applications (such as some critical applications, remote control, autopilot, and TCP applications, etc.) require shorter latency for fast response and data transfer. For example, to further reduce the transmission delay, the TTI length may be reduced to 0.5 ms.

In existing Enhanced Physical Downlink Control Channel (EPDCCH) transmission, a base station (e.g., an evolved node b (enb)) configures an EPDCCH search region to a User Equipment (UE) through Radio Resource Control (RRC) signaling, so that the UE can quickly find its own EPDCCH. The search region is indicated by the number of Physical Resource Block (PRB) pairs and a specific combination index of the PRB pairs. The number of PRB pairs may be set to 2, 4 or 8. The combination index may support any PRB pair combination in the frequency domain and corresponding to a given number of PRB pairs. The number of Resource Elements (REs) required in one EPDCCH may be from 72 bits to 1152 bits for normal Cyclic Prefix (CP) and from 64 bits to 1024 bits for extended CP. Therefore, when the TTI is shortened, the number of REs in the supported EPDCCH region will be insufficient.

Therefore, there is a need in the art for a pdcch transmission scheme with a specific TTI to solve the above-mentioned problems.

Disclosure of Invention

Embodiments of the present disclosure are directed to a method and apparatus for physical downlink control channel transmission with a specific transmission time interval.

According to a first aspect of the present disclosure, there is provided a method for physical downlink control channel transmission with a specific transmission time interval, comprising: receiving first configuration information specific to a user equipment from a base station via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval; and searching the first physical downlink control channel from the potential search area aiming at the current transmission time interval in the current transmission time interval.

In some embodiments, the first configuration information indicates the potential search area in a time domain, and a transmission time interval corresponding to the potential search area is indicated by at least one of: a transmission time interval pattern, a start symbol, and a transmission time interval length.

In some embodiments, the first configuration information indicates the potential search area in a frequency domain.

In some embodiments, searching for the first physical downlink control channel from the potential search region for the current transmission time interval comprises: determining a second physical downlink control channel as the first physical downlink control channel when an identifier of the user equipment is included in a cyclic redundancy check code of the second physical downlink control channel in the potential search area.

In some embodiments, the method further comprises: receiving second configuration information from the base station via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information.

In some embodiments, the second configuration information indicates the potential search area in a time domain.

In some embodiments, the second configuration information comprises at least one of: a transmission time interval mode indication; general control information for the subframe; and downlink control signaling for the subframe for a first transmission time interval.

In some embodiments, the method further comprises: receiving, from the base station, immediate control information for the current transmission time interval using the first physical downlink control channel; and determining control information sent by the base station to the user equipment and a physical downlink shared channel, which is used by the user equipment for receiving data and aims at a specific transmission time interval, based on at least one of the general control information and the instant control information.

According to a second aspect of the present disclosure, there is provided a method for physical downlink control channel transmission with a specific transmission time interval, comprising: receiving control signaling from a base station using a first portion and a second portion of a first physical downlink control channel for a particular transmission time interval, wherein the first portion is allocated in one or more symbols of a beginning of a subframe for transmitting control information, the second portion is allocated in one or more symbols following in the subframe, and wherein the second portion is allocated in a potential search region of the first physical downlink control channel.

In some embodiments, receiving control signaling from the base station using the first and second portions of the first physical downlink control channel for the particular transmission time interval comprises: receiving general control information for the subframe with the first portion; and receiving immediate control information for a current transmission time interval using the second portion.

In some embodiments, the method further comprises: receiving first control signaling in a first transmission time interval in the subframe; and receiving second control signaling in a second transmission time interval, wherein the second control signaling is different from the first control signaling.

In some embodiments, the method further comprises: applying the first control signaling to the second transmission time interval when the second control signaling is not received within the second transmission time interval, wherein the first control signaling is inheritable control signaling.

In some embodiments, the method further comprises: receiving third control signaling in a third transmission time interval in the subframe; and receiving the third control signaling in a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

According to a third aspect of the present disclosure, there is provided a method for physical downlink control channel transmission with a specific transmission time interval, including: transmitting first configuration information specific to a user equipment to the user equipment via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval.

In some embodiments, the method further comprises: transmitting second configuration information to the user equipment via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information.

According to a fourth aspect of the present disclosure, there is provided a method for physical downlink control channel transmission with a specific transmission time interval, comprising: transmitting control signaling to a user equipment using a first portion and a second portion of a first physical downlink control channel for a particular transmission time interval, wherein the first portion is allocated in one or more symbols of a beginning of a subframe for transmitting control information, the second portion is allocated in one or more symbols following in the subframe, and wherein the second portion is allocated in a potential search region of the first physical downlink control channel.

In some embodiments, transmitting control signaling to the user equipment using the first and second portions of the first physical downlink control channel for the particular transmission time interval comprises: transmitting general control information for the subframe using the first portion; and transmitting immediate control information for a current transmission time interval using the second portion.

In some embodiments, the method further comprises: transmitting first control signaling in a first transmission time interval in the subframe; and transmitting second control signaling within a second transmission time interval, wherein the second control signaling is different from the first control signaling.

In some embodiments, the method further comprises: and when the second control signaling is the same as the first control signaling, not transmitting the second control signaling in the second transmission time interval, wherein the first control signaling is inheritable control signaling.

In some embodiments, the method further comprises: transmitting third control signaling in a third transmission time interval in the subframe; and transmitting the third control signaling in a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

According to a fifth aspect of the present disclosure, there is provided an apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising: a first receiving device configured to receive first configuration information specific to a user equipment from a base station via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval; and searching means configured to search, within a current transmission time interval, the first physical downlink control channel from the potential search region for the current transmission time interval.

In some embodiments, the search apparatus is further configured to: determining a second physical downlink control channel as the first physical downlink control channel when an identifier of the user equipment is included in a cyclic redundancy check code of the second physical downlink control channel in the potential search area.

In some embodiments, the apparatus further comprises: a second receiving device configured to receive second configuration information from the base station via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information.

In some embodiments, the apparatus further comprises: a third receiving device configured to receive the immediate control information for the current transmission time interval from the base station by using the first physical downlink control channel; and a determining device configured to determine, based on at least one of the general control information and the immediate control information, control information sent by the base station to a user equipment and a physical downlink shared channel for a specific transmission time interval for the user equipment to receive data.

According to a sixth aspect of the present disclosure, there is provided an apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising: a fourth receiving device configured to receive control signaling from a base station using a first portion and a second portion of a first physical downlink control channel for a specific transmission time interval, wherein the first portion is allocated in one or more symbols of a start of a subframe for transmitting control information, the second portion is allocated in one or more symbols following the subframe, and wherein the second portion is allocated in a potential search region of the first physical downlink control channel.

In some embodiments, the fourth receiving apparatus is further configured to: receiving general control information for the subframe with the first portion; and receiving immediate control information for a current transmission time interval using the second portion.

In some embodiments, the apparatus further comprises a fifth receiving device configured to: receiving first control signaling in a first transmission time interval in the subframe; and receiving second control signaling in a second transmission time interval, wherein the second control signaling is different from the first control signaling.

In some embodiments, the fifth receiving apparatus is further configured to: applying the first control signaling to the second transmission time interval when the second control signaling is not received within the second transmission time interval.

In some embodiments, the fifth receiving apparatus is further configured to: receiving third control signaling in a third transmission time interval in the subframe; and receiving the third control signaling in a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

According to a seventh aspect of the present disclosure, there is provided an apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising: a first transmitting device configured to transmit first configuration information specific to a user equipment to the user equipment via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval.

In some embodiments, the apparatus further comprises: a second transmitting device configured to transmit second configuration information to the user equipment via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information.

According to an eighth aspect of the present disclosure, there is provided an apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising: a third transmitting device configured to transmit control signaling to a user equipment using a first portion and a second portion of a first physical downlink control channel for a specific transmission time interval, wherein the first portion is allocated in one or more symbols of a start of a subframe for transmitting control information, the second portion is allocated in one or more symbols subsequent to the subframe, and wherein the second portion is allocated in a potential search region of the first physical downlink control channel.

In some embodiments, the third transmitting device is further configured to: transmitting general control information for the subframe using the first portion; and transmitting immediate control information for a current transmission time interval using the second portion.

In some embodiments, the apparatus further comprises a fourth transmitting device configured to: transmitting first control signaling in a first transmission time interval in the subframe; and transmitting second control signaling within a second transmission time interval, wherein the second control signaling is different from the first control signaling.

In some embodiments, the fourth transmitting device is further configured to: and when the second control signaling is the same as the first control signaling, not transmitting the second control signaling in the second transmission time interval, wherein the first control signaling is inheritable control signaling.

In some embodiments, the fourth transmitting device is further configured to: transmitting third control signaling in a third transmission time interval in the subframe; and transmitting the third control signaling in a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

According to the transmission mechanism of the physical downlink control channel with the specific transmission time interval, the transmission of the physical downlink control channel with the flexible TTI length can be realized, and the control signaling overhead of data transmission aiming at the short TTI less than 1 millisecond can be effectively reduced, so that the transmission delay is reduced.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this disclosure, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure and not to limit the disclosure. In the drawings:

fig. 1 illustrates a flow diagram of a method 100 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure;

fig. 2 illustrates a schematic diagram of potential search regions for a Short Physical Downlink Control Channel (SPDCCH) in accordance with an embodiment of the disclosure;

fig. 3 illustrates a flow chart of a method 300 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure;

fig. 4 illustrates a flow diagram of a method 400 for a user equipment to search for SPDCCH for a current TTI in accordance with an embodiment of the present disclosure;

fig. 5 illustrates a flow chart of a method 500 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure;

fig. 6 illustrates a schematic diagram of a hybrid SPDCCH according to an embodiment of the present disclosure;

fig. 7 illustrates a schematic diagram of an inheritable SPDCCH according to an embodiment of the present disclosure;

fig. 8 illustrates a schematic diagram of jointly applying a hybrid SPDCCH and an inheritable SPDCCH according to an embodiment of the present disclosure;

fig. 9 illustrates a flow diagram of a method 900 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure;

fig. 10 illustrates a block diagram of an apparatus 1000 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure;

fig. 11 illustrates a block diagram of an apparatus 1100 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure;

fig. 12 illustrates a block diagram of an apparatus 1200 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure; and

fig. 13 illustrates a block diagram of an apparatus 1300 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure.

Like or corresponding reference characters designate like or corresponding parts throughout the several views.

Detailed Description

Hereinafter, various exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that the drawings and description relate to exemplary embodiments only. It is noted that from the following description, alternative embodiments of the structures and methods disclosed herein are readily contemplated and may be employed without departing from the principles of the present disclosure as claimed.

It should be understood that these exemplary embodiments are given solely for the purpose of enabling those skilled in the art to better understand and to practice the present disclosure, and are not intended to limit the scope of the present disclosure in any way.

The terms "including," comprising, "and the like, as used herein, are to be construed as open-ended terms, i.e.," including/including but not limited to. The term "based on" is "based, at least in part, on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment". Relevant definitions for other terms will be given in the following description.

Hereinafter, a technical scheme of physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

In existing Enhanced Physical Downlink Control Channel (EPDCCH) transmission, a base station (e.g., eNB) configures an EPDCCH search region to a User Equipment (UE) through RRC signaling, so that the UE can quickly find its own EPDCCH. However, when the TTI is shortened, the number of REs in the supported EPDCCH region will be insufficient. To support Physical Downlink Control Channel (PDCCH) transmissions with a specific TTI length (e.g., TTI less than 1ms), embodiments of the present disclosure propose an EPDCCH-based Short Physical Downlink Control Channel (SPDCCH), which is for a physical downlink control channel with a flexible TTI length. In addition, in order to reduce TTI, embodiments of the present disclosure further provide a technical solution for reducing overhead of SPDCCH transmission.

Fig. 1 illustrates a flow diagram of a method 100 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure. For example, the method 100 may be performed by a base station (e.g., an eNB). As shown in fig. 1, the method 100 may include a step S101.

In step S101, UE-specific first configuration information is transmitted to the UE via RRC signaling, wherein the first configuration information indicates a potential search area of the first physical downlink control channel for a specific TTI. The first physical downlink control channel described herein is used to refer to SPDCCH, and both are used interchangeably hereinafter. For example, the eNB may configure a potential search region for the UE-specific SPDCCH to each UE that may be scheduled or receive control information within a short TTI of less than 1 ms. According to an embodiment of the present disclosure, the first configuration information may indicate the potential SPDCCH search region in the time domain and the frequency domain. For example, fig. 2 illustrates a schematic diagram of potential search regions for a Short Physical Downlink Control Channel (SPDCCH) in accordance with an embodiment of the disclosure. As shown in fig. 2, in the frequency domain, a potential search region of SPDCCH may be indicated by the number of PRB pairs and the combination index of the PRB pairs; and in the time domain, the potential search region for each TTI may be indicated by a TTI pattern, a starting symbol, and/or a TTI length. In addition, like the EPDCCH, the first configuration information may further include information such as a demodulation reference signal (DMRS) scrambling sequence, a Physical Downlink Shared Channel (PDSCH) Resource Element (RE) mapping, and a quality of service class indicator (QCI).

Additionally or alternatively, the method 100 may further include step S102 (not shown in fig. 1). In step S102, second configuration information is transmitted to the UE via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting the control information, and wherein the second configuration information indicates a potential search region of the SPDCCH in a time domain. For example, the second configuration information may include a TTI mode indication, general control information for the current subframe, and/or downlink control signaling for the first TTI for the current subframe. The TTI mode indication may include a TTI mode, a starting symbol, and/or a TTI length. Thus, the second configuration information may also indicate a potential search region for the UE-specific SPDCCH. In some embodiments, step S102 may be omitted.

Thus, with the method 100 (step S101 and/or step S102), the base station can configure a potential search region for its particular SPDCCH to each UE that may be scheduled or receive control information within a short TTI of less than 1 ms.

Fig. 3 illustrates a flow chart of a method 300 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure. For example, the method 300 may be performed by a UE and may be a response of the UE to the base station performing the method 100. As shown in fig. 3, the method 300 may include steps S301 to S302.

In step S301 (e.g., in response to step S101 of the method 100), UE-specific first configuration information is received from a base station (e.g., eNB) via RRC signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific TTI. As described above, the first physical downlink control channel is used to refer to SPDCCH. According to an embodiment of the present disclosure, the first configuration information may indicate the potential SPDCCH search region in the time domain and the frequency domain. For example, in the frequency domain, the potential search region of SPDCCH may be indicated by the number of PRB pairs and the combination index of the PRB pairs; and in the time domain, the potential search region for each TTI may be indicated by a TTI pattern, a starting symbol, and/or a TTI length. In addition, like the EPDCCH, the first configuration information may further include information such as a demodulation reference signal (DMRS) scrambling sequence, a Physical Downlink Shared Channel (PDSCH) Resource Element (RE) mapping, and a quality of service class indicator (QCI).

Additionally or alternatively, in response to optional step S101 in the method 100, the UE may receive second configuration information from the base station via physical downlink control signaling (e.g., Downlink Control Information (DCI)), wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting the control information. For example, the second configuration information may include a TTI mode indication, general control information for the current subframe, and/or downlink control signaling for the first TTI for the current subframe. The TTI mode indication may include a TTI mode, a starting symbol, and/or a TTI length. Thus, the second configuration information may also indicate a potential search region for the UE-specific SPDCCH.

Next, the method 300 proceeds to step S302. In step S302, a first physical downlink control channel is searched from a potential search region for a current transmission time interval in the current transmission time interval. For example, the UE may search for the SPDCCH for the current TTI according to the TTI pattern and the potential search region of the SPDCCH received via RRC signaling and/or physical downlink control signaling. For example, fig. 4 illustrates a flow diagram of a method 400 for a UE to search for SPDCCH for a current TTI in accordance with an embodiment of the present disclosure. As shown in fig. 4, the method 400 may include steps S401 to S403. In step S401, when an identifier of the UE (e.g., a Radio Network Temporary Identity (RNTI)) is included in a Cyclic Redundancy Check (CRC) of the second physical downlink control channel in the potential search region, the second physical downlink control channel is determined as the SPDCCH for the UE. Next, the method 400 proceeds to step S402, receiving immediate control information for the current TTI from the base station using SPDCCH. Then, the method 400 proceeds to step S403, and determines control information sent by the base station to the UE and a physical downlink shared channel (hereinafter referred to as Short Physical Downlink Shared Channel (SPDSCH)) for a specific transmission time interval used by the UE to receive data (and other operations) based on the general control information (which is included in the second configuration information as described above) and/or the immediate control information.

Thus, with the method 300, the UE is able to find its own SPDCCH and SPDSCH based on the configured SPDCCH potential search region and TTI mode.

However, if the physical downlink control signaling for one TTI is transmitted only in that TTI through SPDCCH, the overhead of the SPDCCH will be linearly increased as the number of TTIs in the subframe increases. Accordingly, embodiments of the present disclosure propose mechanisms for reducing overhead of SPDCCH transmissions to enable a reduction in TTIs.

For example, fig. 5 illustrates a flow diagram of a method 500 for physical downlink control channel transmission with a particular transmission time interval in accordance with an embodiment of the disclosure. For example, method 500 may be performed by a base station (e.g., an eNB). As shown in fig. 5, the method 500 may include step S501.

In step S501, control signaling is transmitted to a UE using a first part (hereinafter abbreviated as SPDCCH-1) and a second part (hereinafter abbreviated as SPDCCH-2) of an SPDCCH. Wherein SPDCCH-1 is allocated in one or more symbols at the beginning of a subframe for transmission of control information and SPDCCH-2 is allocated in one or more subsequent symbols in the subframe. For example, fig. 6 illustrates a schematic diagram of a hybrid SPDCCH according to an embodiment of the present disclosure. As shown in fig. 6, the base station may transmit the general control information for the current subframe through physical downlink control signaling using SPDCCH-1. The general control information transmitted in SPDCCH-1 may include antenna ports, reference signaling, Physical Uplink Control Channel (PUCCH) power control, and Sounding Reference Signal (SRS) requests. The new control signaling type transmitted in SPDCCH-1 may also include a potential search region for SPDCCH-2 within the current subframe, a TTI length, a duration of the TTI of UE-specific SPDCCH-2, and so on. With SPDCCH-1, control signaling overhead due to shortened TTIs (e.g., less than 1ms) can be reduced and backward compatibility can be maintained as much as possible. Further, the base station may utilize SPDCCH-2 to transmit immediate control information for the current TTI. The immediate control information transmitted in SPDCCH-2 may include downlink UE scheduling (resource allocation and power offset for data transmission, Modulation and Coding Strategy (MCS), precoding and number of layers), hybrid retransmission request (HARQ) information, spdsch mapping, and quasi co-location indicators. Alternatively, the power offset, MCS, precoding, and number of layers for data transmission may also be transmitted over SPDCCH-1.

Additionally or alternatively, the method 500 may further include step S502 (not shown in fig. 5). In step S502, in a current subframe, transmitting first control signaling in a first TTI and transmitting second control signaling in a second TTI, wherein the second control signaling is different from the first control signaling; further, when the second control signaling is the same as the first control signaling, the second control signaling is not transmitted within the second TTI. That is, in one subframe and for the same UE, the control signaling transmitted in the SPDCCH for one TTI may be inherited in the next TTI. For example, fig. 7 illustrates a schematic diagram of an inheritable SPDCCH according to an embodiment of the present disclosure. As shown in fig. 7, the base station transmits updated control information only when the control information for the current TTI needs to be changed, thereby being able to reduce control signaling overhead due to a shortened TTI (e.g., less than 1 ms). The SPDCCH may be inherited only for the same UE and within the same subframe.

In some embodiments, the downlink control signaling may be divided into inheritable control signaling and non-inheritable control signaling. For example, inheritable control signaling may include carrier indication, antenna port, precoding, and MCS, among others; the non-inheritable control signaling may include a new data indication, HARQ information, and the like. Additionally or alternatively, in step S502, in the current subframe, third control signaling is transmitted within a third TTI and third control signaling is transmitted within a fourth TTI, wherein the third control signaling is non-inheritable control signaling. For example, in some embodiments, a TTI is assumed_xAnd TTI_x+1Using the same control information for scheduling the same UE in addition to the MCS, then TTI_x+1Only the MCS may need to be updated. E.g. TTI_x+1May contain only TTIs_xPart of the control information already in possession (e.g., with TTI)_xDifferent control information with). Furthermore, if some control information is not in TTI_x+1Can be indicated in the TTI, the UE can assume that the network has reused the same parameter settings associated with such control information, e.g., such control information can have been indicated in the TTI_xOr already transmitted in SPDCCH-1 as described in connection with step S501, etc. In some embodiments, HARQ information is assumed to be non-inheritable control signaling and simultaneous TTIs_xAnd TTI_x+1Using the same control information for scheduling the same UE in addition to the MCS, then TTI_x+1The MCS and HARQ information need to be updated simultaneously.

It should be appreciated that steps S501 and S502 may be performed in parallel, i.e. jointly applying the hybrid SPDCCH and the inheritable SPDCCH, to further reduce the control signaling overhead due to the shortened TTI. For example, fig. 8 illustrates a schematic diagram of jointly applying a hybrid SPDCCH and an inheritable SPDCCH according to an embodiment of the present disclosure. Further, it will also be understood that steps S501 and S502 may both be optionally performed, for example, only step S501 or only step S502 is performed, which is not limited by embodiments of the present disclosure.

Fig. 9 illustrates a flow diagram of a method 900 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the disclosure. For example, method 900 may be performed by a UE and may be a response by the UE to the base station performing method 500. As shown in fig. 9, method 900 may include step S901.

In step S901, control signaling is received from a base station using SPDCCH-1 and SPDCCH-2. Wherein SPDCCH-1 is allocated in one or more symbols at the beginning of a subframe for transmission of control information and SPDCCH-2 is allocated in one or more subsequent symbols in the subframe. The UE may receive the general control information for the current subframe through physical downlink control signaling using SPDCCH-1. The general control information received in SPDCCH-1 may include antenna ports, reference signaling, PUCCH power control, and SRS requests. The new control signaling type received in SPDCCH-1 may also include a potential search region for SPDCCH-2 within the current subframe, a TTI length, a duration of the TTI of UE-specific SPDCCH-2, and so on. With SPDCCH-1, control signaling overhead due to shortened TTIs (e.g., less than 1ms) can be reduced and backward compatibility can be maintained as much as possible. Further, the UE may utilize SPDCCH-2 to receive immediate control information for the current TTI. The immediate control information received in SPDCCH-2 may include downlink UE scheduling (resource allocation and power offset for data transmission, MCS, precoding, and number of layers), HARQ information, SPDSCH RE mapping, and quasi co-location indicator. Alternatively, the power offset, MCS, precoding, and number of layers for data transmission may also be received over SPDCCH-1.

Additionally or alternatively, method 900 may further include step S902 (not shown in fig. 9). In step S902, in a current subframe, receiving first control signaling in a first TTI and receiving second control signaling in a second TTI, wherein the second control signaling is different from the first control signaling; further, the first control signaling is applied to the second TTI when the second control signaling is not received within the second TTI. That is, in one subframe and for the same UE, the control signaling transmitted in the SPDCCH for one TTI may be inherited in the next TTI. In some embodiments, the downlink control signaling may be divided into inheritable control signaling and non-inheritable control signaling. Additionally or alternatively, in step S902, in the current subframe, third control signaling is received within a third TTI and third control signaling is received within a fourth TTI, wherein the third control signaling is non-inheritable control signaling.

For purposes of clarity, certain optional steps of

methods

100, 300, 400, 500, and/or 900 are not shown in fig. 1, 3-5, and 9. However, it should be understood that these steps not shown, and any combination thereof with the steps shown, are included within the scope of the present disclosure.

Fig. 10 illustrates a block diagram of an apparatus 1000 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure. For example, device 1000 may be implemented as or as part of a base station. As shown in fig. 10, apparatus 1000 may include a first transmitting device 1001 configured to transmit UE-specific first configuration information to a UE via RRC signaling, wherein the first configuration information indicates a potential search region of SPDCCH.

According to an embodiment of the present disclosure, the first configuration information may indicate the potential search area in a time domain, and a transmission time interval corresponding to the potential search area is indicated by at least one of: TTI mode, starting symbol, and TTI length. The first configuration information may indicate the potential search area in a frequency domain.

According to an embodiment of the present disclosure, the apparatus 1000 further comprises: a second transmitting device configured to transmit second configuration information to the UE via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting the control information. Additionally or alternatively, the second configuration information may also indicate a potential search region of the SPDCCH in the time domain.

According to an embodiment of the present disclosure, the second configuration information includes at least one of: a transmission time interval mode indication; general control information for a current subframe; and downlink control signaling for the first transmission time interval for the current subframe.

Fig. 11 illustrates a block diagram of an apparatus 1100 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure. For example, device 1100 may be implemented as or as part of a base station. As shown in fig. 11, apparatus 1100 may include a third transmitting device 1101 configured to transmit control signaling to a UE using SPDCCH-1 and SPDCCH-2, wherein SPDCCH-1 is allocated in one or more symbols of a start of a subframe for transmitting control information, SPDCCH-2 is allocated in one or more symbols subsequent to the subframe, and wherein SPDCCH-2 is allocated in a potential search region of SPDCCH-2.

According to an embodiment of the present disclosure, the third transmission apparatus 1101 is configured to: transmitting general control information for a current subframe using SPDCCH-1; and transmitting the immediate control information for the current transmission time interval using SPDCCH-2.

According to an embodiment of the present disclosure, the apparatus 1100 further comprises a fourth transmission device configured to: transmitting, in a subframe, first control signaling within a first transmission time interval; and transmitting second control signaling within a second transmission time interval, wherein the second control signaling is different from the first control signaling. The fourth transmitting device is further configured to: the second control signaling is not transmitted for a second transmission time interval when the second control signaling is the same as the first control signaling. The fourth transmitting device is further configured to: transmitting third control signaling in a subframe within a third transmission time interval; and transmitting third control signaling within a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

Fig. 12 illustrates a block diagram of an apparatus 1200 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure. For example, device 1200 may be implemented as or as part of a UE. As shown in fig. 12, the apparatus 1200 comprises a first receiving means 1201 configured to receive UE-specific first configuration information from a base station via RRC signaling, wherein the first configuration information indicates a potential search region of SPDCCH; and searching means 1202 configured to search for SPDCCH from the potential search region for the current transmission time interval within the current transmission time interval.

According to an embodiment of the present disclosure, the search apparatus 1202 is configured to: when the identifier of the UE is included in the CRC of the second physical downlink control channel in the potential search region, determining the second physical downlink control channel as the SPDCCH for the UE.

According to an embodiment of the present disclosure, the apparatus 1200 further comprises: a second receiving device configured to receive second configuration information from the base station via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting the control information. Additionally or alternatively, the second configuration information may indicate a potential search region of the SPDCCH in the time domain.

According to an embodiment of the present disclosure, the apparatus 1200 further comprises: third receiving means configured to receive instantaneous control information for a current transmission time interval from a base station using SPDCCH; and determining means configured to determine control information transmitted by the base station to the UE and SPDSCH used for receiving data based on at least one of the general control information and the immediate control information.

Fig. 13 illustrates a block diagram of an apparatus 1300 for physical downlink control channel transmission with a specific transmission time interval according to an embodiment of the present disclosure. For example, device 1300 may be implemented as or as part of a UE. As shown in fig. 13, apparatus 1300 includes a fourth receiving means 1301 configured to receive control signaling from a base station using SPDCCH-1 and SPDCCH-2, wherein SPDCCH-1 is allocated in one or more symbols of a start of a subframe for transmitting control information, SPDCCH-2 is allocated in one or more symbols subsequent to the subframe, and wherein SPDCCH-2 is allocated in a potential search region of SPDCCH-2.

According to an embodiment of the present disclosure, the fourth receiving apparatus 1301 is configured to: receiving general control information for a current subframe by using SPDCCH-1; and receiving the immediate control information for the current transmission time interval using SPDCCH-2.

According to an embodiment of the present disclosure, the apparatus 1300 further comprises a fifth receiving device configured to: receiving a first control signaling in a subframe within a first transmission time interval; and receiving second control signaling in a second transmission time interval, wherein the second control signaling is different from the first control signaling. The fifth receiving apparatus is further configured to: the first control signaling is applied to the second transmission time interval when the second control signaling is not received within the second transmission time interval. The fifth receiving apparatus is further configured to: receiving third control signaling in a subframe within a third transmission time interval; and receiving third control signaling in a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

For purposes of clarity, certain optional features of

apparatus

1000, 1100, 1200 and/or 1300 have not been shown in fig. 10-13. However, it should be understood that the various features described above with reference to fig. 1-9 are equally applicable to

apparatus

1000, 1100, 1200, and/or 1300. Also, each of the devices in the

apparatuses

1000, 1100, 1200 and/or 1300 may be a hardware module or a software module. For example, in certain embodiments,

devices

1000, 1100, 1200, and/or 1300 may be implemented in part or in whole using software and/or firmware, e.g., as a computer program product embodied on a computer-readable medium. Alternatively or additionally,

devices

1000, 1100, 1200, and/or 1300 may be implemented partially or entirely in hardware, e.g., as Integrated Circuits (ICs), Application Specific Integrated Circuits (ASICs), system on a chip (SOCs), Field Programmable Gate Arrays (FPGAs), etc. The scope of the present disclosure is not limited in this respect.

In summary, according to the embodiments of the present disclosure, a method and an apparatus for physical downlink control channel transmission with a specific transmission time interval are provided. The embodiment of the disclosure can realize the transmission of the physical downlink control channel with flexible TTI length, and can effectively reduce the control signaling overhead for the data transmission of the short TTI less than 1 millisecond, thereby realizing the reduction of the transmission delay.

In general, the various exemplary embodiments of this invention may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Certain aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of the embodiments of the invention may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

Also, blocks in the flow diagrams may be viewed as method steps, and/or as operations that result from operation of computer program code, and/or as a plurality of coupled logic circuit elements understood to perform the associated functions. For example, embodiments of the invention include a computer program product comprising a computer program tangibly embodied on a machine-readable medium, the computer program comprising program code configured to implement the method described above.

Within the context of this disclosure, a machine-readable medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination thereof. More detailed examples of a machine-readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical storage device, a magnetic storage device, or any suitable combination thereof.

Computer program code for implementing the methods of the present invention may be written in one or more programming languages. These computer program codes may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the computer or other programmable data processing apparatus, cause the functions/acts specified in the flowchart and/or block diagram block or blocks to be performed. The program code may execute entirely on the computer, partly on the computer, as a stand-alone software package, partly on the computer and partly on a remote computer or entirely on the remote computer or server.

Additionally, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking or parallel processing may be beneficial. Likewise, while the above discussion contains certain specific implementation details, this should not be construed as limiting the scope of any invention or claims, but rather as describing particular embodiments that may be directed to particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Various modifications, adaptations, and other embodiments of the present invention will become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings. Any and all modifications will still fall within the scope of the non-limiting and exemplary embodiments of this invention. Furthermore, the foregoing description and drawings provide instructive benefits and other embodiments of the present invention set forth herein will occur to those skilled in the art to which these embodiments of the present invention pertain.

It is to be understood that the embodiments of the invention are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A method for physical downlink control channel transmission with a specific transmission time interval, comprising:

receiving first configuration information specific to a user equipment from a base station via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval;

receiving second configuration information regarding the potential search area from the base station via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information; and

searching for the first physical downlink control channel from the potential search area for a current transmission time interval within the current transmission time interval based on at least one of the first configuration information and the second configuration information.

2. The method of claim 1, wherein the first configuration information indicates the potential search area in a time domain, and wherein a transmission time interval to which the potential search area corresponds is indicated by at least one of: a transmission time interval pattern, a start symbol, and a transmission time interval length.

3. The method of claim 1, wherein the first configuration information indicates the potential search area in a frequency domain.

4. The method of claim 1, wherein searching for the first physical downlink control channel from the potential search area for the current transmission time interval comprises:

determining a second physical downlink control channel as the first physical downlink control channel when an identifier of the user equipment is included in a cyclic redundancy check code of the second physical downlink control channel in the potential search area.

5. The method of claim 1, wherein the second configuration information indicates the potential search area in a time domain.

6. The method of claim 1, wherein the second configuration information comprises at least one of:

a transmission time interval mode indication;

general control information for the subframe; and

downlink control signaling for the subframe for a first transmission time interval.

7. The method of claim 6, further comprising:

receiving, from the base station, immediate control information for the current transmission time interval using the first physical downlink control channel; and

and determining control information sent by the base station to the user equipment and a physical downlink shared channel (PDCCH) of the user equipment for receiving data and aiming at a specific transmission time interval based on at least one of the general control information and the instant control information.

8. A method for physical downlink control channel transmission with a specific transmission time interval, comprising:

receiving control signaling from a base station using a first portion and a second portion of a first physical downlink control channel for a particular transmission time interval,

wherein the first portion is allocated in a first one or more symbols of a subframe for transmission of control information, the second portion is allocated in a subsequent one or more symbols of the subframe, and

wherein the second portion is allocated in a potential search area of the first physical downlink control channel.

9. The method of claim 8, wherein receiving control signaling from a base station using the first and second portions of the first physical downlink control channel for a particular transmission time interval comprises:

receiving general control information for the subframe with the first portion; and

receiving, with the second portion, immediate control information for a current transmission time interval.

10. The method of claim 8, further comprising:

receiving first control signaling in a first transmission time interval in the subframe; and

receiving second control signaling in a second transmission time interval, wherein the second control signaling is different from the first control signaling.

11. The method of claim 10, further comprising:

applying the first control signaling to the second transmission time interval when the second control signaling is not received within the second transmission time interval, wherein the first control signaling is inheritable control signaling.

12. The method of claim 10, further comprising:

receiving third control signaling in a third transmission time interval in the subframe; and

receiving the third control signaling within a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

13. A method for physical downlink control channel transmission with a specific transmission time interval, comprising:

transmitting first configuration information specific to a user equipment to the user equipment via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval; and

transmitting second configuration information regarding the potential search area to the user equipment via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information.

14. The method of claim 13, wherein the first configuration information indicates the potential search area in a time domain, and wherein a transmission time interval to which the potential search area corresponds is indicated by at least one of: a transmission time interval pattern, a start symbol, and a transmission time interval length.

15. The method of claim 13, wherein the first configuration information indicates the potential search area in a frequency domain.

16. The method of claim 13, wherein the second configuration information indicates the potential search area in a time domain.

17. The method of claim 13, wherein the second configuration information comprises at least one of:

a transmission time interval mode indication;

general control information for the subframe; and

18. A method for physical downlink control channel transmission with a specific transmission time interval, comprising:

transmitting control signaling to the user equipment using the first and second portions of the first physical downlink control channel for a particular transmission time interval,

19. The method of claim 18, wherein transmitting control signaling to the user equipment using the first and second portions of the first physical downlink control channel for a particular transmission time interval comprises:

transmitting general control information for the subframe using the first portion; and

transmitting immediate control information for a current transmission time interval using the second portion.

20. The method of claim 18, further comprising:

transmitting first control signaling in a first transmission time interval in the subframe; and

transmitting second control signaling within a second transmission time interval, wherein the second control signaling is different from the first control signaling.

21. The method of claim 20, further comprising:

and when the second control signaling is the same as the first control signaling, not transmitting the second control signaling in the second transmission time interval, wherein the first control signaling is inheritable control signaling.

22. The method of claim 20, further comprising:

transmitting third control signaling in a third transmission time interval in the subframe; and

transmitting the third control signaling within a fourth transmission interval, wherein the third control signaling is non-inheritable control signaling.

23. An apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising:

a first receiving device configured to receive first configuration information specific to a user equipment from a base station via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval;

a second receiving device configured to receive second configuration information regarding the potential search area from the base station via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information; and

a searching device configured to search the first physical downlink control channel from the potential search area for a current transmission time interval within the current transmission time interval based on at least one of the first configuration information and the second configuration information.

24. The apparatus of claim 23, wherein the first configuration information indicates the potential search area in a time domain, and wherein a transmission time interval to which the potential search area corresponds is indicated by at least one of: a transmission time interval pattern, a start symbol, and a transmission time interval length.

25. The apparatus of claim 23, wherein the first configuration information indicates the potential search area in a frequency domain.

26. The apparatus of claim 23, wherein the searching means is further configured to:

27. The apparatus of claim 23, wherein the second configuration information indicates the potential search area in a time domain.

28. The apparatus of claim 23, wherein the second configuration information comprises at least one of:

a transmission time interval mode indication;

general control information for the subframe; and

29. The apparatus of claim 28, further comprising:

a third receiving device configured to receive the immediate control information for the current transmission time interval from the base station by using the first physical downlink control channel; and

a determining device configured to determine, based on at least one of the general control information and the instantaneous control information, control information sent by the base station to a user equipment and a physical downlink shared channel for a specific transmission time interval for the user equipment to receive data.

30. An apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising:

a fourth receiving device configured to receive control signaling from the base station using the first part and the second part of the first physical downlink control channel for a specific transmission time interval,

31. The apparatus of claim 30, wherein the fourth receiving means is further configured to:

32. The apparatus of claim 30, further comprising a fifth receiving device configured to:

33. The apparatus of claim 32, wherein the fifth receiving means is further configured to:

34. The apparatus of claim 32, wherein the fifth receiving means is further configured to:

35. An apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising:

a first transmitting device configured to transmit first configuration information specific to a user equipment to the user equipment via radio resource control signaling, wherein the first configuration information indicates a potential search region of a first physical downlink control channel for a specific transmission time interval; and

a second transmitting device configured to transmit second configuration information regarding the potential search area to the user equipment via physical downlink control signaling, wherein the second configuration information is located in one or more symbols of a start of a subframe for transmitting control information.

36. The apparatus of claim 35, wherein the first configuration information indicates the potential search area in a time domain, and wherein a transmission time interval to which the potential search area corresponds is indicated by at least one of: a transmission time interval pattern, a start symbol, and a transmission time interval length.

37. The apparatus of claim 35, wherein the first configuration information indicates the potential search area in a frequency domain.

38. The apparatus of claim 35, wherein the second configuration information indicates the potential search area in a time domain.

39. The apparatus of claim 35, wherein the second configuration information comprises at least one of:

a transmission time interval mode indication;

general control information for the subframe; and

40. An apparatus for physical downlink control channel transmission with a specific transmission time interval, comprising:

a third transmitting device configured to transmit control signaling to the user equipment using the first part and the second part of the first physical downlink control channel for a specific transmission time interval,

41. The apparatus of claim 40, wherein the third transmitting means is further configured to:

42. The apparatus of claim 40, further comprising a fourth transmission device configured to:

43. The apparatus of claim 42, wherein the fourth transmitting means is further configured to:

44. The apparatus of claim 42, wherein the fourth transmitting means is further configured to: