CN103442444A

CN103442444A - PDCCH signal sending method, PDCCH signal receiving method, base station, UE and system

Info

Publication number: CN103442444A
Application number: CN2013103630022A
Authority: CN
Inventors: 曲秉玉; 官磊; 薛丽霞
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2010-02-11
Filing date: 2010-04-30
Publication date: 2013-12-11
Anticipated expiration: 2030-04-30
Also published as: CN103428881B; CN103476126A; CN103442444B; CN103428881A; CN103476126B; CN102158979A

Abstract

The invention provides a PDCCH signal sending method, a PDCCH signal receiving method, a base station, UE and a system. The PDCCH signal sending method includes the steps that the base station determines the position of a first searching space and the position of a second searching space, and the base station only sends a PDCCH signal without a CIF to the UE in the physical overlapping area when the length of the PDCCH signal without the CIF in the first searching space is equal to the length of a PDCCH signal with the CIF in the second searching space and a physical overlapping area exists between the first searching space and the second searching space. According to the PDCCH signal sending method, the PDCCH signal receiving method, the base station, the UE and the system, obscure scheduling of the base station can be avoided, and therefore the problem of analysis errors of the UE can be solved.

Description

PDCCH signaling sending and receiving method, base station, UE and system

Technical Field

The embodiment of the invention relates to the technical field of communication, in particular to a method for sending and receiving Physical Downlink Control Channel (PDCCH) signaling, a base station, User Equipment (UE) and a system.

Background

In an evolved LTE system (LTE-Advanced, abbreviated as LTE-a), a Carrier Aggregation (CA) technology is introduced, that is, resources of a plurality of Component Carriers (CCs) are simultaneously scheduled to a User Equipment (UE) for use, so as to meet higher peak rate and service requirements.

In a system that does not adopt the CA technology, a physical downlink Control Channel (PDCCH for short) signaling may only schedule resources of one carrier. In a system adopting the CA technology, if one UE aggregates multiple carriers to transmit data, the UE needs corresponding multiple PDCCH signaling.

In LTE-a systems, there are two ways in which resources can be scheduled. One mode is common carrier Scheduling (SCS), that is, a PDCCH signaling on a certain carrier may only schedule the carrier or the resource of an uplink carrier corresponding to the carrier. Another method is Cross-carrier Scheduling (CCs), that is, PDCCH signaling on a certain carrier may schedule resources of the carrier or other carriers. In the cross-Carrier scheduling method, a Carrier Indicator Field (CIF) needs to be added to a UE-specific PDCCH signaling to indicate which Carrier resource the PDCCH signaling uses for scheduling. In particular, CIF may not be added to PDCCH signaling common to multiple users, so that UE in LTE-a system and UE in LTE system coexist.

The base station notifies the UE of which Resource scheduling method is currently specifically used by sending a semi-static Radio Resource Control (RRC for short) signaling. Namely, the UE is informed whether to adopt the CCS mode or the SCS mode currently. When the UE adopts the SCS mode to schedule resources in the RRC idle state or the RRC connection state, the PDCCH signaling does not comprise the CIF. When the UE adopts a CCS mode to schedule resources in a connection state, the PDCCH signaling comprises a CIF. After the base station sends the semi-static RRC signaling to the UE, if the UE receives the semi-static RRC signaling, the UE can detect and analyze the PDCCH signaling according to a resource scheduling mode indicated in the semi-static RRC signaling. However, after the base station issues the semi-static RRC signaling, it is determined that the UE has correctly received the semi-static RRC signaling only after receiving an RRC Connection Reconfiguration Complete signaling (RRC Connection Reconfiguration Complete) fed back by the UE, and the base station has a problem of scheduling ambiguity in a period from when the base station issues the semi-static RRC signaling to when the base station receives the RRC Connection Reconfiguration Complete signaling fed back by the UE.

The following problems exist in the prior art: in the period from the time when the base station issues the semi-static RRC signaling to the time when the base station receives the RRC connection reconfiguration completion signaling fed back by the UE, the base station has the problem of scheduling ambiguity, thereby causing the problem of UE analysis error.

Disclosure of Invention

The embodiment of the invention provides a PDCCH signaling sending and receiving method, a base station, UE and a system, which are used for solving the problem of UE analysis error caused by the fact that the length of a PDCCH signaling which does not comprise a CIF in a CSS of a current carrier is equal to the length of a PDCCH signaling which comprises a CIF in a UESS which is used for scheduling another carrier with a bandwidth smaller than that of the current carrier on the current carrier.

The embodiment of the invention provides a PDCCH signaling sending method, which comprises the following steps:

determining positions of a first search space and a second search space of the UE;

and if the length of the PDCCH signaling without the Carrier Indicator Field (CIF) in the first search space is equal to the length of the PDCCH signaling with the CIF in the second search space, and a physical overlapping region exists between the first search space and the second search space, only sending the PDCCH signaling without the CIF to the UE in the physical overlapping region.

The embodiment of the invention also provides a method for sending the PDCCH signaling, which comprises the following steps:

and if the length of the PDCCH signaling without the Carrier Indicator Field (CIF) in the first search space is equal to the length of the PDCCH signaling with the CIF in the second search space, and a physical overlapping region exists between the first search space and the second search space, in the physical overlapping region, after receiving Radio Resource Control (RRC) connection reconfiguration completion signaling sent by the UE, only sending the PDCCH signaling with the CIF to the UE.

if the length of a first PDCCH signaling in the first search space is equal to the length of a second PDCCH signaling in the second search space, the first PDCCH signaling is a PDCCH signaling without a Carrier Indicator Field (CIF), the second PDCCH signaling is a PDCCH signaling with the CIF, and a physical overlapping region exists between the first search space and the second search space, in the physical overlapping region, a third PDCCH signaling or a fourth PDCCH signaling is sent to the UE within a time interval from sending a Radio Resource Control (RRC) signaling to receiving an RRC connection reconfiguration completion signaling fed back by the UE, the third PDCCH signaling is a PDCCH signaling without the CIF, the fourth PDCCH signaling is a PDCCH signaling with the CIF, the signaling length of the third PDCCH signaling is not equal to the signaling length of the fourth PDCCH signaling, and the length of the third PDCCH signaling is different from the length of the first PDCCH signaling, the length of the fourth PDCCH signaling is different from the length of the first PDCCH signaling.

The embodiment of the invention also provides a method for receiving the PDCCH signaling, which comprises the following steps:

the method comprises the steps that the length of PDCCH signaling which does not comprise a Carrier Indicator Field (CIF) in a first search space of User Equipment (UE) is equal to the length of PDCCH signaling which comprises the CIF in a second search space of the UE, and a physical overlapping area exists between the first search space and the second search space, the PDCCH signaling which does not comprise the CIF is received in the physical overlapping area, and the PDCCH signaling which does not comprise the CIF is analyzed only according to a set analysis rule of the PDCCH signaling which does not comprise the CIF.

the method comprises the steps that the length of PDCCH signaling which does not comprise a Carrier Indicator Field (CIF) in a first search space of User Equipment (UE) is equal to the length of PDCCH signaling which comprises the CIF in a second search space of the UE, and a physical overlapping area exists between the first search space and the second search space, in the physical overlapping area, after the UE correctly analyzes Radio Resource Control (RRC) signaling from a base station, the PDCCH signaling comprising the CIF is received, and the PDCCH signaling comprising the CIF is analyzed only according to a set analysis rule of the PDCCH signaling comprising the CIF.

An embodiment of the present invention further provides a base station, including:

a first determining module, configured to determine locations of a first search space and a second search space of a UE;

a first sending module, configured to, after the first determining module determines the positions of a first search space and a second search space of the UE, send, to the UE, only PDCCH signaling that does not include a CIF in the physical overlapping area when a PDCCH signaling length that does not include the CIF in the first search space is equal to a PDCCH signaling length that includes the CIF in the second search space and the first search space and the second search space have the physical overlapping area.

a second determining module, configured to determine locations of a first search space and a second search space of a user equipment UE;

a second sending module, configured to, after the first determining module determines the positions of a first search space and a second search space of the UE, send a third PDCCH signaling or a fourth PDCCH signaling to the UE in a time interval from sending a radio resource control, RRC, signaling to the UE to receiving an RRC connection reconfiguration complete signaling fed back by the UE in a physical overlapping region if the length of the first PDCCH signaling in the first search space is equal to the length of the second PDCCH signaling in the second search space, where the first PDCCH signaling is a PDCCH signaling that does not include a carrier indicator field CIF, the second PDCCH signaling is a PDCCH signaling that includes a CIF, and the first PDCCH signaling and the second PDCCH signaling are in the physical overlapping region, where the third PDCCH signaling is not equal to the length of the PDCCH signaling that includes the CIF, and the length of the third PDCCH signaling is equal to the length of the PDCCH signaling that includes the CIF, the length of the third PDCCH signaling is different from that of the first PDCCH signaling, and the length of the fourth PDCCH signaling is different from that of the first PDCCH signaling.

a third determining module, configured to determine locations of the first search space and the second search space of the UE;

a third sending module, configured to, after the third determining module determines the positions of the first search space and the second search space of the UE, send, if the length of the PDCCH signaling that does not include the carrier indicator field CIF in the first search space is equal to the length of the PDCCH signaling that includes the CIF in the second search space, and there is a physical overlapping area between the first search space and the second search space, the PDCCH signaling that includes the CIF only to the UE after receiving the radio resource control RRC connection reconfiguration complete signaling sent by the UE in the physical overlapping area.

An embodiment of the present invention further provides a UE, including:

a receiving module, configured to receive, in a first search space, a PDCCH signaling length that does not include a CIF, where the PDCCH signaling length is equal to a PDCCH signaling length that includes a CIF in a second search space, and a PDCCH signaling that does not include a CIF and is sent by a base station is received in a physical overlapping area when the first search space and the second search space have the physical overlapping area;

and the analysis module is used for analyzing the PDCCH signaling received by the receiving module only according to the set analysis rule of the PDCCH signaling not including the CIF.

An embodiment of the present invention further provides a UE, including:

a second receiving module, configured to receive, in a first search space of the UE, PDCCH signaling including CIF of a Carrier Indicator Field (CIF), where a length of the PDCCH signaling is equal to a length of the PDCCH signaling including CIF in a second search space of the UE, and when a physical overlapping area exists between the first search space and the second search space, the PDCCH signaling including CIF is received after the UE correctly resolves a Radio Resource Control (RRC) configuration signaling from a base station in the physical overlapping area;

and the second analysis module is used for analyzing the PDCCH signaling containing the CIF received by the receiving module only according to the set analysis rule of the PDCCH signaling containing the CIF.

An embodiment of the present invention further provides a communication system, including the aforementioned base station including the first determining module and the first sending module, and the aforementioned UE including the receiving module and the parsing module.

The embodiment of the present invention further provides a communication system, which includes a UE and the base station including the second determining module and the second sending module as described above.

By the PDCCH signaling sending and receiving method, the base station, the UE and the system, scheduling ambiguity of the base station can be avoided, and the UE can determine whether the PDCCH signaling comprises CIF or not after receiving the PDCCH signaling, so that analysis errors of the UE can be avoided.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a flowchart illustrating a PDCCH signaling transmission method according to an embodiment of the present invention;

FIG. 2 is a flowchart illustrating a PDCCH signaling transmission method according to another embodiment of the present invention;

FIG. 3 is a flowchart illustrating a PDCCH signaling transmission method according to another embodiment of the present invention;

FIG. 4 is a flowchart illustrating a PDCCH signaling transmission method according to another embodiment of the present invention;

FIG. 5 is a flowchart of an embodiment of a PDCCH signaling reception method according to the present invention;

FIG. 6 is a flowchart illustrating a PDCCH signaling reception method according to another embodiment of the present invention;

FIG. 7 is a flowchart illustrating a PDCCH signaling reception method according to another embodiment of the present invention;

fig. 8 is a schematic structural diagram of a base station according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of another embodiment of a base station according to the present invention;

fig. 10 is a schematic structural diagram of a UE embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In a Long Term Evolution (LTE) system, a base station (eNB) and a UE perform resource scheduling on one carrier. The minimum time unit of the base station scheduling resource is one subframe, the length is 1 millisecond, after the scheduled UE demodulates and decodes the PDCCH signaling in the search space of the PDCCH according to the signaling length of the PDCCH and the Control Channel Element (CCE) level of the search space, it uses its own Radio Network Temporary Identifier (RNTI) to descramble Cyclic Redundancy Check (CRC) to Check and determine whether the currently detected PDCCH signaling is its own PDCCH signaling, and after determining that it is its own PDCCH signaling, it further performs subsequent processing. The PDCCH signaling carries time-frequency resource allocation information indicating a physical data channel (the physical data channel may be uplink or downlink).

One search space is a collection of a series of logically contiguous CCEs, which are the smallest units that make up PDCCH signaling. PDCCH signaling for a UE may be transmitted using four CCE levels, 1, 2, 4 and 8, with different CCE levels having different coding rates. PDCCH signaling of different CCE levels have different search spaces, but physically, the search spaces of different PDCCH signaling may overlap, i.e., some or all of the same-numbered CCEs may be included in different search spaces.

The search space may be divided into CSS and UESS, which are different search spaces but may overlap physically, i.e. some or all of the same numbered CCEs may be included in different search spaces. The CSS is a space in which all UEs need to detect, includes 16 CCEs, and can only transmit PDCCH signaling with a CCE level of 4 or 8, and the number of searches in the CSS corresponding to the two CCE levels is 4 and 2, respectively (4 × 4=8 × 2= 16). Each UE has a specific UESS, each UESS is determined by a specific RNTI and subframe number, the UESS may contain CCE levels of 1, 2, 4 and 8, and the number of searches within the UESS corresponding to these four CCE levels is 6, 2 and 2, respectively.

The PDCCH signaling may have different DCI formats according to different transmission modes of scheduling data, resource allocation modes, and the like, for example, Downlink Control Information (DCI) format 0, DCI format 1A, DCI format 1B, DCI format 1C, DCI format 1D, DCI format 1, DCI format 2A, DCI format 2, DCI format 3A, and the like, where the PDCCH signaling of different DCI formats generally has different lengths, and RNTIs scrambled on the PDCCH signaling may also be different.

The PDCCH signaling for scheduling some Information common to multiple users may be transmitted in the CSS, and the scrambled RNTI may also be some RNTI common to multiple users, for example, paging RNTI (paging RNTI), system Information RNTI (system Information RNTI), random access Response RNTI (rach Response RNTI), and RNTI related to Transmit Power Control (TPC).

PDCCH signaling scrambled by a specific RNTI of the UE is typically transmitted in the UESS, for example, PDCCH signaling scrambled by using a Semi-Persistent Scheduling-Cell-RNTI (SPS-C-RNTI) or a Cell-RNTI (Cell-RNTI, C-RNTI).

The PDCCH signaling of DCI format 1A may be transmitted in CSS, scrambled using paging RNTI, system information RNTI, or random access response RNTI. The PDCCH signaling for DCI format 1A may also be transmitted in the UESS, scrambled using cell RNTI or SPS-C-RNTI.

The length of the PDCCH signaling of DCI format 1A is the same as the length of the PDCCH signaling of DCI format 3, DCI format 3A, and DCI format 0, and the header distinction ratio of the PDCCH signaling of DCI format 1A and the PDCCH signaling of DCI format 0 is used to distinguish the two signaling. PDCCH signaling of DCI format 1A and PDCCH signaling of DCI format 0 are distinguished from PDCCH signaling of DCI format 3 and PDCCH signaling of DCI format 3A by using different RNTI scrambling.

PDCCH signaling of DCI format 1A scrambled by cell RNTI and SPS-C-RNTI can be transmitted in UESS or CSS, thus the detection times of PDCCH signaling are not increased. The times of detecting PDCCH signaling by the UE is related to the signaling length, and a series of detection times are increased when the signaling length is more than one. Because the PDCCH signaling of DCI format 3 or DCI format 3A transmitted in the CSS always needs to be detected, and both the PDCCH signaling and the PDCCH signaling have the same length as the PDCCH signaling of DCI format 0 and DCI format 1A, the number of times that the UE detects the PDCCH signaling is not increased.

The base station configures one of 7 transmission modes for the UE through semi-static RRC signaling according to different data transmission modes, resource allocation modes, and the like. In each transmission mode, the UE needs to detect PDCCH signaling of two DCI formats, where the PDCCH signaling of one DCI format is related to the currently allocated transmission mode of the UE, and the PDCCH signaling of the other DCI format is PDCCH signaling of DCI format 1A and DCI format 0 that are unrelated to the currently allocated transmission mode of the UE, that is, the UE needs to detect PDCCH signaling of DCI format 1A and DCI format 0 regardless of the allocated transmission mode of the UE. For example, if the base station allocates transmission mode 3 and an open-loop Multiple Input Multiple Output (MIMO) transmission mode to the UE, the UE needs to detect the PDCCH signaling of DCI format 2A, and the UE needs to detect the PDCCH signaling of DCI format 0 and DCI format 1A. Wherein PDCCH signaling of DCI format 2A is related to transmission mode 3. If the base station allocates a transmission mode 4, a closed-loop MIMO transmission mode, to the UE, the UE needs to detect the PDCCH signaling of DCI format 2, and the UE needs to detect the PDCCH signaling of DCI format 0 and DCI format 1A. Wherein PDCCH signaling of DCI format 2 is related to transmission mode 4.

Assume a scenario a: after the base station sends the semi-static RRC signaling for notifying the UE of the current resource scheduling mode to the time when the base station receives the RRC connection reconfiguration complete signaling returned by the UE, and after the base station receives the RRC connection reconfiguration complete signaling returned by the UE, the length of the PDCCH signaling in the CSS of the current carrier that does not include the DCI format 0 or the DCI format 1A of the CIF may be equal to the length of the PDCCH signaling in another format that includes the CIF in the UESS that is used for scheduling another carrier with a bandwidth smaller than that of the current carrier on the current carrier.

For example, one signaling is PDCCH signaling of DCI format 0 or 1A not including CIF in CSS of the current carrier CC1, and the other signaling is PDCCH signaling of another format including CIF in UESS on the current carrier CC1 for scheduling other carrier CC2 with bandwidth smaller than carrier CC 1. Since the bandwidth of the scheduled carrier CC2 is smaller than the bandwidth of the carrier CC1, the number of resource allocation bits required in the PDCCH signaling is small, and then the length of the PDCCH signaling of DCI format 0 or 1A not including CIF in the CSS of the current carrier CC1 may be equal to the length of the PDCCH signaling of another format including CIF in the UESS on the current carrier CC1 for scheduling other carrier CC2 with a bandwidth smaller than the carrier CC 1. When there is a physical overlap region between CSS and UESS, the UE may erroneously resolve whether PDCCH signaling searched in the physical overlap region is used for scheduling resources in carrier CC1 or for scheduling resources in carrier CC 2.

Taking downlink data as an example, once the UE incorrectly analyzes the PDCCH signaling, the UE will receive the downlink data on the wrong carrier, and the subsequent UE may feed back a non-acknowledgement (NACK) message to the base station, and the base station will resend the original data, but the UE still does not determine how to correctly analyze the PDCCH signaling, and the UE still cannot correctly receive the data, and the UE keeps the wrong data in the buffer until the base station reaches the maximum retransmission number, which results in the buffer pollution of the Hybrid Automatic Repeat-reQuest (HARQ for short) of the UE.

How embodiments of the present invention solve the above-described problems will be described in detail below. In each embodiment of the present invention, it may be assumed that, in a data resource scheduling manner such as CCS, the PDCCH signaling of DCI format 1A or DCI format 0 transmitted in CSS does not include CIF, and the PDCCH signaling of DCI format 1A or DCI format 0 may only schedule a resource on a carrier where the PDCCH signaling is currently located or an uplink carrier corresponding to the carrier.

Alternatively, it may also be assumed that, in the resource scheduling manner such as CCS, a PDCCH signaling transmitted in a certain UESS does not include a CIF, and the PDCCH signaling may schedule only a resource on a carrier where the signaling is currently located or an uplink carrier corresponding to the carrier.

Fig. 1 is a flowchart of an embodiment of a PDCCH signaling method according to the present invention, including:

step 101, the base station determines the positions of the first search space and the second search space. PDCCH signaling transmitted in the first search space may not include CIF, the first search space may be CSS and or UESS, signaling transmitted in the second search space may include CIF, and the second search space may be UESS.

Step 102, if the length of the PDCCH signaling without CIF in the first search space is equal to the length of the PDCCH signaling with CIF in the second search space, and there is a physical overlapping area between the first search space and the second search space, the base station sends the PDCCH signaling without CIF to the UE in the physical overlapping area.

The PDCCH signaling sent by the base station may include resource allocation information and other control information, for example, may include carrier activation or deactivation information, and may include information for triggering a physical random access procedure.

The embodiment shown in fig. 1 limits the overlapping area of two search spaces for transmitting PDCCH signaling in one of the search spaces, which is actually a method for orthogonalizing the search spaces, and may also adopt a method for orthogonalizing the search spaces, that is, the two search spaces are not overlapped, so as to solve the scheduling ambiguity problem of the base station caused by the fact that the length of PDCCH signaling not including CIF in the first search space is equal to the length of PDCCH signaling including CIF in the second search space, for example, if the CSS and the UESS are physically overlapped, the CCE sizes of the CSS and the UESS may not be changed, and the CSS position is fixed, and the UESS and the CSS are not overlapped by one configuration parameter, and in particular, the UESS and the CSS may be continuously placed.

Fig. 5 is a flowchart of an embodiment of a PDCCH signaling receiving method according to the present invention, which includes:

step 501, if the length of the PDCCH signaling without CIF in the first search space is equal to the length of the PDCCH signaling with CIF in the second search space, and the first search space and the second search space have a physical overlapping area, the UE receives the PDCCH signaling without CIF sent by the base station in the physical overlapping area.

Step 502, the PDCCH signaling is analyzed according to the set rule. The rules of the setup may specify that the base station and the UE resolve according to the pre-agreed meaning of the various fields in the PDCCH signaling.

If the base station does not include the CIF in the PDCCH signaling, the UE may parse according to a parsing rule that the PDCCH signaling does not include the CIF after receiving the PDCCH signaling. What parsing rule the UE specifically adopts can be negotiated by the UE and the base station in advance.

In the above embodiment, when the length of the PDCCH signaling that does not include the CIF in the first search space is equal to the length of the PDCCH signaling that includes the CIF in the second search space, and the first search space and the second search space have a physical overlapping region, the base station is required to send the PDCCH signaling that does not include the CIF to the UE, so that the PDCCH signaling that is sent to the UE is always the PDCCH signaling that does not include the CIF, the UE may determine that the PDCCH signaling received in the physical overlapping region does not include the CIF, and the resource allocated in the PDCCH signaling is also determined to be the resource on the carrier used for carrying the PDCCH signaling, which may not cause an analysis error of the UE.

For example, after the base station sends the semi-static RRC signaling for notifying the UE of the current resource scheduling manner to the base station receives the configuration acknowledgement completion signaling returned by the UE, and after the base station receives the configuration acknowledgement completion signaling fed back by the UE, if the length of the PDCCH signaling in the DCI format 0 or DCI format 1A of the CIF is not included in the CSS of the current carrier used to carry the PDCCH signaling in the UE is equal to the length of the PDCCH signaling in another format including the CIF in the UESS of the UE used to schedule another carrier having a bandwidth smaller than that of the current carrier on the current carrier, and there is a physical overlapping region between the CSS and the UESS, the base station sends the PDCCH signaling without the CIF in the physical overlapping region, and the signaling carries resource allocation information for the UE. In one embodiment, the UE may negotiate with the base station in advance, and none of the PDCCH signaling sent in the physical overlapping area includes CIF. Then, after receiving the PDCCH signaling, the UE may determine that the PDCCH signaling does not include CIF, and the resource allocated in the PDCCH signaling is also determined to be a resource on a carrier for carrying the PDCCH signaling, which may not cause UE parsing error.

In the embodiments shown in fig. 1 and 5, the first search space may be a CSS, the second search space is a UE-specific UESS, and CCE ranks of the first search space and the second search space may be 4 or 8. Alternatively, the first search space and the second search space include two UESSs for scheduling different component carriers of the UE.

In the embodiment shown in fig. 1, if the first search space is the CSS and the second search space is the UESS, the second search space is not limited so much because in the second search space, even if the PDCCH signaling length of 4 or 8CCE level is equal to the PDCCH signaling length without CIF in the CSS, so that the PDCCH signaling cannot be scheduled in the physical overlapping region, the base station may also transmit the PDCCH signaling with

CCE level

1 or 2 in the physical overlapping region. Even if the PDCCH signaling length with CCE level 4 is equal to the PDCCH signaling length without CIF in the CSS, so that the PDCCH cannot be scheduled in the physical overlapping region, the base station may schedule the PDCCH signaling with CCE level 8 if the search space with CCE level 8 does not overlap the CSS.

In the above embodiment, in the period from when the base station issues the RRC signaling to when the base station receives the RRC connection reconfiguration complete signaling fed back by the UE, the base station can clearly know which way the user terminal receives, so as to solve the problem of an analysis error of the control signaling transmitted by the base station on the UE side.

In addition, the whole scheduling freedom of the first search space is completely reserved, i.e. no scheduling limitation is generated on the first search space, so that the problem of scheduling ambiguity of the base station during RRC reconfiguration is solved to the maximum extent.

Fig. 2 is a flowchart illustrating another embodiment of a PDCCH signaling method according to the present invention, including:

step 201, the base station determines the positions of the first search space and the second search space.

Step 202, if the length of a first PDCCH signaling in the first search space is equal to the length of a second PDCCH signaling in the second search space, the first PDCCH signaling is a PDCCH signaling not including a carrier indicator field CIF, the second PDCCH signaling is a PDCCH signaling including a CIF, and there is a physical overlapping region between the first search space and the second search space, in the physical overlapping region, a third PDCCH signaling or a fourth PDCCH signaling is sent to the UE within a time interval from sending a radio resource control, RRC, signaling to the UE to receiving an RRC connection reconfiguration complete signaling fed back by the UE, the third PDCCH signaling is a PDCCH signaling not including a CIF, the fourth PDCCH signaling is a PDCCH signaling including a CIF, and the signaling length of the third PDCCH signaling is not equal to the signaling length of the fourth PDCCH signaling, the length of the third PDCCH signaling is different from the length of the first PDCCH signaling, the length of the fourth PDCCH signaling is different from the length of the first PDCCH signaling. And after receiving the RRC connection reconfiguration completion signaling returned by the UE, the base station sends the second PDCCH signaling, namely the PDCCH signaling comprising the CIF to the UE. The third PDCCH signaling or the fourth PDCCH signaling may be other types of PDCCH signaling except the first PDCCH signaling and the second PDCCH signaling, and the other types of PDCCH signaling except the first PDCCH signaling and the second PDCCH signaling sent by the base station is PDCCH signaling that the base station knows not to be incorrectly resolved by the UE. For example, there are two formats of PDCCH signaling in each current transmission mode, and for two PDCCH signaling (plus CIF) in a certain transmission mode corresponding to a carrier scheduled by a cross-carrier, assuming that one of them is equal to the PDCCH signaling length in a certain format without CIF in the CSS of the carrier where the PDCCH is located, the eNB may send another PDCCH signaling in the current mode, where the signaling length is not equal to the PDCCH signaling length in the certain format without CIF in the CSS of the carrier where the PDCCH is located, and at this time, the UE may not erroneously analyze the PDCCH signaling. Or, there may also be two UE-specific PDCCH signaling without CIF in the CSS of the carrier where the PDCCH is located, where one of the PDCCH signaling may be erroneously parsed by the UE, and then the base station may send the other PDCCH signaling without CIF to the UE.

Fig. 6 is a flowchart of another embodiment of a PDCCH signaling receiving method according to the present invention, including:

step 601, if the length of the PDCCH signaling without CIF in the first search space is equal to the length of the PDCCH signaling with CIF in the second search space, and there is a physical overlapping area between the first search space and the second search space, in the physical overlapping area, after the UE correctly resolves the RRC signaling, the UE receives the PDCCH signaling with CIF sent by the base station.

Step 602, the UE parses the PDCCH signaling including CIF only according to the set parsing rule for the PDCCH signaling including CIF.

If the PDCCH signaling sent by the base station includes CIF, the UE may parse according to a parsing rule that the PDCCH signaling includes CIF after receiving the PDCCH signaling. What parsing rule the UE specifically adopts can be negotiated by the UE and the base station in advance.

In the above embodiment, when the length of the PDCCH signaling that does not include the CIF in the first search space is equal to the length of the PDCCH signaling that includes the CIF in the second search space, and there is a physical overlapping region between the first search space and the second search space, the base station may not send the PDCCH signaling that includes the CIF in a time interval from when the base station sends the RRC signaling to when the base station receives the acknowledgement signaling fed back by the UE, because the UE may not receive the correct RRC configuration signaling, the UE may consider that the received PDCCH signaling does not include the CIF, thereby causing an analysis error. Therefore, after receiving the configuration confirmation completion signaling returned by the UE, the base station can send the PDCCH signaling including the CIF to the UE; however, in the time interval from the RRC signaling sent by the base station to the acknowledgement signaling fed back by the UE, the base station may only send other types of PDCCH signaling to the UE besides the first PDCCH signaling and the second PDCCH signaling. For the UE side, after the UE correctly analyzes the RRC configuration signaling, the UE only receives the PDCCH signaling including the CIF sent by the base station.

In the embodiment shown in fig. 2, the first search space may be a CSS, the second search space is a UE-specific UESS, and CCE ranks of the first search space and the second search space are 4 or 8. Alternatively, the first search space and the second search space include two UESSs for scheduling different component carriers of the UE.

If the first search space is the CSS and the second search space is the UESS, the number of detections of PDCCH signaling in the first search space will not be increased by the method in the embodiment shown in fig. 2. In addition, because the scheduling freedom degree of the second search space is larger than that of the first search space (because the second search space can realize cross-carrier scheduling, and the first search space only allows same-carrier scheduling), the scheme completely reserves all the scheduling freedom degrees of the second search space and does not generate any scheduling limitation on the second search space.

Fig. 3 is a flowchart illustrating another embodiment of a PDCCH signaling method according to the present invention, including:

step 301, the base station determines the positions of the first search space and the second search space.

Step 302, if the length of a first PDCCH signaling in a first search space is equal to the length of a second PDCCH signaling in a second search space, where the first PDCCH signaling is a PDCCH signaling that does not include a carrier indicator field CIF, the second PDCCH signaling is a PDCCH signaling that includes a CIF, and a physical overlapping region exists between the first search space and the second search space, in the physical overlapping region, a base station sends PDCCH signaling of other types except the first PDCCH signaling and the second PDCCH signaling to a UE in a time interval from when the base station sends an RRC signaling to when an acknowledgement signaling fed back by the UE is received.

The PDCCH signaling of other types except for the first PDCCH signaling and the second PDCCH signaling may be a third PDCCH signaling or a fourth PDCCH signaling, where the third PDCCH signaling is a PDCCH signaling that does not include a CIF, the fourth PDCCH signaling is a PDCCH signaling that includes a CIF, and a signaling length of the third PDCCH signaling is not equal to a signaling length of the fourth PDCCH signaling.

As with the embodiment shown in fig. 3, the problem that exists in scenario B as follows can be solved.

For example, one scenario B: if the PDCCH signaling for scheduling two carriers has separate UESS on one carrier and the two UESSs have a physical overlapping area, the base station scheduling ambiguity problem also exists during the period from the time when the base station sends the semi-static RRC signaling for notifying the UE of the current resource scheduling mode to the time when the base station receives the configuration confirmation completion signaling returned by the UE. For example, before transmission, the resource scheduling mode of the UE is SCS, and PDCCH signaling transmitted by the base station to the UE does not include CIF. After the UE receives the semi-static RRC signaling for notifying the UE of the current resource scheduling mode, the resource scheduling mode of the UE becomes CCS. In the period of time when the base station does not receive the configuration confirmation completion signaling fed back by the UE, the base station does not determine whether the PDCCH signaling sent to the UE needs to include CIF, which results in fuzzy scheduling of the base station. And when the UE correctly receives the RRC configuration signaling of the base station and switches to the CCS mode, the CIF is added to the PDCCH scheduled in the two UESS, the PDCCH signaling of different carriers can be automatically distinguished and scheduled, and the problem can not be caused even if the signaling lengths of the PDCCH with the CIF are equal.

For scenario B, this situation cannot be solved by limiting the base station to only send PDCCH signaling including CIF or PDCCH signaling not including CIF within the time interval from sending semi-static RRC signaling to receiving acknowledgement signaling returned by the UE. If the base station is limited to only send the PDCCH signaling without the CIF within the time interval from sending the semi-static RRC signaling to receiving the configuration completion confirmation signaling fed back by the UE, and the UE has correctly analyzed the semi-static RRC signaling, the UE considers that the received PDCCH signaling contains the CIF, thereby causing the UE to analyze incorrectly. If the base station is limited to only send the PDCCH signaling including the CIF within the time interval from sending the semi-static RRC signaling to receiving the RRC connection reconfiguration completion signaling fed back by the UE, and the UE does not correctly analyze the semi-static RRC signaling, the UE considers that the received PDCCH signaling does not include the CIF, thereby causing the UE to analyze incorrectly.

If the embodiment shown in fig. 3 is adopted, the base station sends other types of PDCCH signaling besides the first PDCCH signaling and the second PDCCH signaling in the physical overlapping area, so that scheduling ambiguity of the base station can be avoided, and parsing errors of the UE can also be avoided.

After the base station receives the RRC connection reconfiguration completion signaling fed back by the UE, the resource scheduling mode of the UE is changed into CCS, even if two UESSs of the UE have a physical overlapping area, the base station does not have the problem of scheduling ambiguity and the UE does not have analysis errors due to the fact that the PDCCH signaling in the CCS mode comprises CIF.

In the embodiment shown in fig. 3, the first search space and the second search space comprise two UESSs for scheduling different component carriers of the UE.

By adopting the method in the embodiment shown in fig. 3, the problem that the UE erroneously resolves the PDCCH is solved by the method implemented by the base station itself without specifying any behavior of the UE, that is, without any influence on the operation of the UE, and the method is simple and easy to operate.

In one embodiment, two component carriers CC1 and CC2 of one UE, PDCCH signaling is sent on CC1, CC1 includes search space CSS, search space UESS1 and search space UESS2, PDCCH signaling in CSS on CC1 is used to schedule the component carrier CC1 and does not include CIF, PDCCH signaling in UESS1 on CC1 is used to schedule the component carrier CC1 and does not include CIF, PDCCH signaling in UESS2 on CC1 is used to schedule CC2 across carriers and includes CIF.

In one case, when the length of PDCCH signaling including no CIF in UESS1 is equal to the length of PDCCH signaling including CIF in UESS2, and UESS1 and UESS2 have a physical overlapping region, the base station transmits PDCCH signaling including no CIF to the UE in the physical overlapping region; and the length of the PDCCH signaling without CIF in the CSS is equal to the length of the PDCCH signaling without CIF in the UESS2, and when there is a physical overlapping region between the CSS and the UESS2, in the physical overlapping region, the base station sends the PDCCH signaling including CIF to the UE, so that when the length of the PDCCH signaling without CIF in the UESS1, the length of the PDCCH signaling including CIF in the UESS2 is equal to the length of the PDCCH signaling without CIF in the UESS1, and there is a problem of scheduling ambiguity in the common overlapping region.

Or,

when the length of the PDCCH signaling without the CIF in UESS1 is equal to the length of the PDCCH signaling with the CIF in UESS2, and a physical overlapping region exists between UESS1 and UESS2, the base station sends the PDCCH signaling with the CIF to the UE in the physical overlapping region; and the length of the PDCCH signaling without CIF in the CSS is equal to the length of the PDCCH signaling without CIF in the UESS2, and when there is a physical overlapping region between the CSS and the UESS2, in the physical overlapping region, the base station sends the PDCCH signaling without CIF to the UE, so that when the length of the PDCCH signaling without CIF in the UESS1, the length of the PDCCH signaling with CIF in the UESS2 is equal to the length of the PDCCH signaling without CIF in the UESS1, and there is a problem of scheduling ambiguity in the common overlapping region.

Based on the above situation, in an embodiment, in an overlapping area of the three, the base station only sends PDCCH signaling without CIF to the UE; or the base station only sends PDCCH signaling including CIF to the UE.

If the base station only sends the PDCCH signaling without the CIF to the UE in the overlapped area of the three, the data can be scheduled on the carrier CC1 in which the PDCCH is placed preferentially, so that the scheduling priority of the carrier is ensured, and the smooth transition of scheduling during RRC reconfiguration is ensured;

if the base station only sends PDCCH signaling including CIF to the UE in the overlapping area of the three, the scheduling freedom of the UESS of the carrier CC2 scheduled by cross-carrier is ensured.

A method for sending Physical Downlink Control Channel (PDCCH) signaling comprises the following steps:

determining the positions of a first search space, a second search space and a third search space of User Equipment (UE);

and if the PDCCH signaling length of the CIF in the carrier indicator field is not included in the first search space, and the PDCCH signaling length of the CIF not included in the third search space is equal to the PDCCH signaling length of the CIF included in the second search space, and a physical overlapping region exists in the first search space, the second search space and the third search space, only sending the PDCCH signaling including the CIF or only sending the PDCCH signaling not including the CIF to the UE in the physical overlapping region.

A Physical Downlink Control Channel (PDCCH) signaling receiving method comprises the following steps:

if the PDCCH signaling length of the CIF in the first search space is equal to the PDCCH signaling length of the CIF in the second search space, and the first search space, the second search space and the third search space have a physical overlapping region, receiving the PDCCH signaling including the CIF or the PDCCH signaling not including the CIF sent by the base station in the physical overlapping region;

and the UE analyzes the PDCCH signaling according to a set rule.

A base station, comprising:

a sixth determining module, configured to determine locations of a first search space, a second search space, and a third search space of a user equipment UE;

a sixth sending module, configured to send only PDCCH signaling including CIF or only PDCCH signaling not including CIF to the UE in a physical overlapping area if the PDCCH signaling length not including CIF in the first search space is equal to the PDCCH signaling length not including CIF in the third search space and there is a physical overlapping area in the first search space, the second search space, and the third search space.

A user equipment, UE, comprising:

a seventh receiving module, configured to receive, in a physical overlapping area where a PDCCH signaling length that does not include a carrier indicator field CIF in the first search space is equal to a PDCCH signaling length that does not include a CIF in a third search space and the PDCCH signaling length that includes a CIF in the second search space, the PDCCH signaling that includes the CIF or the PDCCH signaling that does not include the CIF and is sent by a base station in the physical overlapping area;

and the seventh analysis module is used for analyzing the PDCCH signaling by the UE according to a set rule.

Fig. 4 is a flowchart illustrating another embodiment of a PDCCH signaling method according to the present invention, including:

step 401, the base station determines the positions of the first search space and the second search space.

Step 402, if the length of the PDCCH signaling including no CIF in the first search space is equal to the length of the PDCCH signaling including CIF in the second search space, and there is a physical overlapping area between the first search space and the second search space, the base station sends the PDCCH signaling including CIF after adding one bit to the UE in the physical overlapping area.

In this embodiment, in a case where the length of PDCCH signaling including no CIF in the first search space is equal to the length of PDCCH signaling including CIF in the second search space, and there is a physical overlapping area between the first search space and the second search space, the base station is required to transmit PDCCH signaling including CIF after being increased by one bit in the physical overlapping area. Because the length of the PDCCH signaling which includes the CIF and is received by the UE is one bit longer than that of the PDCCH signaling which does not include the CIF, the UE can determine that the PDCCH signaling with the longer signaling length includes the CIF, and the analysis error of the UE can be avoided.

For example, after the base station sends the semi-static RRC signaling for notifying the UE of the current resource scheduling manner to the time when the base station receives the RRC connection reconfiguration complete signaling fed back by the UE, and after the base station receives the RRC connection reconfiguration complete signaling fed back by the UE, if the length of the PDCCH signaling in DCI format 0 or DCI format 1A that does not include CIF in the CSS of the current carrier used to carry the PDCCH signaling in the UE is equal to the length of the PDCCH signaling in another format that includes CIF in the UESS of the UE that is used to schedule another carrier with a bandwidth smaller than that of the current carrier on the current carrier, and there is a physical overlapping region (limited to two CCE levels of 4 or 8) between the CSS and the UESS, the base station sends the PDCCH signaling in the CSS mode that includes CIF after adding one bit to the UE in the physical overlapping region. Therefore, the UE can determine that the received PDCCH signaling comprises the CIF, and the analysis error of the UE is avoided.

Assuming that the first search space is a CSS and the second search space is a UESS, by using the method in the embodiment shown in fig. 4, bit padding may occur only for a length of PDCCH signaling that does not include a CIF in the CSS, which is equal to the length of PDCCH signaling that includes a CIF in the UESS, there is a physical overlapping region between the CSS and the UESS, and only when the CCE level is 4 or 8, and the overhead is small, and the length of PDCCH signaling that does not include a CIF in the CSS is not affected, which may ensure that PDCCH signaling that does not include a CIF in the CSS may be compatible with a format of PDCCH signaling in the LTE system.

Since the search spaces of different CCE grades can be physically overlapped, and the different CCE grades correspond to different rate matching of channel coding, when the length of the PDCCH signaling after bit filling is equal to certain specific length, the PDCCH signaling of different CCE grades can be analyzed into the PDCCH signaling of the UE through the check of the C-RNTI of the UE, but the PDCCH signaling sent by the base station can only be of one CCE grade, so that the condition that the PDCCH signaling is analyzed by the UE wrongly can occur. Therefore, if the length of the PDCCH signaling filled with one bit is equal to the length of the PDCCH signaling causing different CCE levels to pass the C-RNTI check of the UE in the embodiment of the present invention, one bit is further filled to avoid this situation.

Fig. 7 is a flowchart of another embodiment of a PDCCH signaling receiving method according to the present invention, which includes:

step 701, if the PDCCH signaling length without CIF in the first search space is equal to the PDCCH signaling length with CIF in the second search space, and there is a physical overlapping area between the first search space and the second search space, the UE receives the PDCCH signaling with CIF sent by the base station after adding one bit in the physical overlapping area.

Step 702, analyzing the PDCCH signaling according to the set rule.

If the PDCCH signaling sent by the base station is the PDCCH signaling added with one bit and including the CIF, after receiving the PDCCH signaling, the UE may parse according to a parsing rule that the PDCCH signaling includes the CIF and is added with one bit. What parsing rule the UE specifically adopts can be negotiated by the UE and the base station in advance.

In an embodiment, a base station may determine positions of a first search space and a second search space of a user equipment UE, and if a length of PDCCH signaling including a carrier indicator field CIF is not included in the first search space and is equal to a length of PDCCH signaling including the CIF in the second search space, and there is an overlapping region between the first search space and the second search space, in the overlapping region, after receiving radio resource control, RRC, connection reconfiguration complete signaling sent by the UE, the base station may send only the PDCCH signaling including the CIF to the UE;

the first search space is a common search space, CSS, and the second search space is a user equipment specific search space, UESS, of the UE.

In one embodiment, if the length of PDCCH signaling including no CIF in the first search space is equal to the length of PDCCH signaling including CIF in the second search space, and there is a physical overlapping region between the first search space and the second search space, the PDCCH signaling including no CIF in the first search space is first signaling, and the PDCCH signaling including CIF in the second search space is second signaling, in the physical overlapping region, the first signaling and the second signaling may be distinguished by existing or redundant or padded bits or states with fixed absolute positions in PDCCHs of the first signaling and the second signaling. The absolute position is fixed, which means that the field is a field determined by the bit number in the PDCCH, such as the last bit except the CRC bit.

Specifically, taking DCI formats 0 and 1A under the scenario that the bandwidths of uplink and downlink carriers are equal in an FDD system as an example, the last bit of DCI format 1A except the CRC bit is a bit of the power command field, the last bit of DCI format 0 except the CRC bit is a padding bit, and the default is padding "0". It may be specified that the PDCCH is represented by the first signaling when the last bit is "0", and the PDCCH is represented by the second signaling when the last bit is "1". If the last bit originally has some indication meaning, i.e. the bit is a non-redundant or padding bit or state, the field may be restricted from parsing, or the meaning of the bit may be indicated by other fields in the PDCCH, such as interchanging the meaning with the power control field in the PDCCH that schedules downlink data.

In one embodiment, in a system supporting carrier aggregation, uplink control signaling (including uplink ACK/NACK, uplink channel state information, etc.) is fed back on one uplink carrier specific to a UE, this uplink carrier is referred to as an uplink primary carrier, a downlink carrier paired with this uplink carrier is referred to as a downlink primary carrier, and other downlink carriers of the UE are referred to as downlink non-primary carriers. One method of power control of the uplink control channel is controlled by a two-bit power control command field in a PDCCH for scheduling downlink data, since the uplink control channels of all downlink carriers corresponding to a certain UE are fed back only on the uplink primary carrier, therefore, only the power control command field in the PDCCH for scheduling the downlink main carrier is needed to carry out the power control of the uplink control channel, the power control command field in the PDCCH for scheduling the downlink non-main carrier is redundant, the redundant field may be made to indicate the meaning of the absolute position fixed field distinguishing the first signaling from the second signaling, and the UE may distinguish the first signaling from the second signaling through the absolute position fixed field, and the meaning to be indicated by the field with fixed absolute position can be obtained by resolving the redundant field.

Fig. 8 is a schematic structural diagram of a base station according to an embodiment of the present invention, where the base station 1 includes: a first determination module 11 and a first sending module 12. Wherein the first determining module 11 is configured to determine the locations of the first search space and the second search space. The first sending module 12 is configured to, when a PDCCH signaling length that does not include a CIF in the first search space is equal to a PDCCH signaling length that includes a CIF in the second search space, and a physical overlapping region exists between the first search space and the second search space, send, in the physical overlapping region, only the PDCCH signaling that does not include a CIF to the UE, or, if the first PDCCH signaling is a PDCCH signaling that does not include a CIF in the first search space and the second PDCCH signaling is a PDCCH signaling that includes a CIF in the second search space, send, to the UE, the PDCCH signaling that includes a CIF after being increased by one bit. Or, in a time interval from the sending of the RRC signaling by the base station to the receiving of the confirmation signaling fed back by the UE, the base station sends other types of PDCCH signaling except the first PDCCH signaling and the second PDCCH signaling to the UE; and after receiving the configuration confirmation completion signaling returned by the UE, the base station only sends the PDCCH signaling containing the CIF to the UE.

In one embodiment, a base station may comprise:

Fig. 9 is a schematic structural diagram of another embodiment of the base station of the present invention, where the base station 1 includes: a second determination module 13 and a second sending module 14. Wherein the second determination module 13 is configured to determine the locations of the first search space and the second search space. A second sending module 14, configured to, after the second determining module determines the positions of the first search space and the second search space of the UE, send a third PDCCH signaling or a fourth PDCCH signaling to the UE in a time interval from sending a Radio Resource Control (RRC) signaling to the UE to receiving an RRC connection reconfiguration complete signaling fed back by the UE in a physical overlapping region if the length of the first PDCCH signaling in the first search space is equal to the length of the second PDCCH signaling in the second search space, where the first PDCCH signaling is a PDCCH signaling that does not include a Carrier Indicator Field (CIF), the second PDCCH signaling is a PDCCH signaling that includes a CIF, and the first PDCCH signaling is not equal to the length of the fourth PDCCH signaling, the length of the third PDCCH signaling is different from that of the first PDCCH signaling, and the length of the fourth PDCCH signaling is different from that of the first PDCCH signaling.

In the embodiment shown in fig. 9, the first search space and the second search space comprise two UESSs for scheduling different component carriers of the UE.

As shown in fig. 10, which is a schematic structural diagram of an embodiment of the UE of the present invention, the UE2 includes a receiving module 21 and an analyzing module 22. A receiving module 21, configured to receive, in a physical overlapping area, PDCCH signaling that does not include CIF and is sent by a base station in a first search space, where the PDCCH signaling length that does not include CIF is equal to the PDCCH signaling length that includes CIF in a second search space, and the first search space and the second search space have the physical overlapping area, or receive PDCCH signaling that includes CIF and is sent by the base station after being added by one bit. The parsing module 22 is configured to parse the PDCCH signaling received by the receiving module 21 according to the set parsing rule for the PDCCH signaling not including CIF. Or after the UE correctly analyzes the RRC signaling, the UE only receives the PDCCH signaling including the CIF sent by the base station.

In one embodiment, the user equipment UE may further include:

a second receiving module, configured to receive, in a first search space of the UE, PDCCH signaling including a carrier indicator field CIF, when a length of the PDCCH signaling not including the CIF in the first search space is equal to a length of the PDCCH signaling including the CIF in a second search space of the UE, and a physical overlapping region exists between the first search space and the second search space, the PDCCH signaling including the CIF is received after the UE correctly resolves a radio resource control, RRC, signaling from a base station in the physical overlapping region;

An embodiment of the present invention further provides a communication system, which may include a base station as shown in fig. 8 and a UE as shown in fig. 10, where the base station sends PDCCH signaling to the UE by using the method in the foregoing method embodiment, and the UE receives the PDCCH signaling sent by the base station by using the method in the foregoing method embodiment.

The present invention also provides a communication system, which may include a UE and the UE shown in fig. 9, where the base station sends PDCCH signaling to the UE by using the method described in the foregoing method embodiment, and the UE may receive the PDCCH signaling sent by the base station according to the existing method.

According to the base station and the UE provided by the embodiment of the invention, if the length of the PDCCH signaling which does not include the CIF in the first search space is equal to the length of the PDCCH signaling which includes the CIF in the second search space, and the first search space and the second search space have a physical overlapping region, the base station is limited to send the PDCCH signaling which does not include the CIF to the UE in the physical overlapping region.

Or, in a time interval from the sending of the RRC signaling by the base station to the receiving of the confirmation signaling fed back by the UE, the base station sends other types of PDCCH signaling except the first PDCCH signaling and the second PDCCH signaling to the UE; and after receiving the configuration confirmation completion signaling returned by the UE, the base station sends a PDCCH signaling containing the CIF to the UE.

Or, if the length of the signaling of the first PDCCH signaling not including the CIF in the first search space is equal to the length of the signaling of the second PDCCH signaling including the CIF in the second search space, and the first search space and the second search space have a physical overlapping region, in the physical overlapping region, the base station sends PDCCH signaling of other types except the first PDCCH signaling and the second PDCCH signaling to the UE within a time interval from the base station sending the semi-static RRC signaling to the reception of the RRC connection reconfiguration complete signaling fed back by the UE, so that scheduling ambiguity of the base station can be avoided, and thus, an analysis error of the UE is avoided.

In one embodiment, the base station determines the positions of the first search space and the second search space, and if the length of the PDCCH signaling without including the CIF in the first search space is equal to the length of the PDCCH signaling including the CIF in the second search space, and a physical overlapping region exists between the first search space and the second search space, the base station sends the PDCCH signaling including the CIF to the UE in the physical overlapping region.

If the length of the PDCCH signaling which does not include the CIF in the first search space is equal to the length of the PDCCH signaling which includes the CIF in the second search space, and a physical overlapping area exists between the first search space and the second search space, the UE receives the PDCCH signaling which includes the CIF and is sent by the base station in the physical overlapping area, and the PDCCH signaling is analyzed according to the set rule.

In the foregoing embodiment, when the length of the PDCCH signaling that does not include the CIF in the first search space is equal to the length of the PDCCH signaling that includes the CIF in the second search space, and a physical overlapping region exists between the first search space and the second search space, the base station is required to send the PDCCH signaling that includes the CIF to the UE, so that the PDCCH signaling that is sent to the UE always includes the CIF can determine that the PDCCH signaling received in the overlapping region always includes the CIF, and the resource allocated in the PDCCH signaling is also determined to be a resource on a carrier used for carrying the PDCCH signaling, which may not cause an analysis error of the UE.

For example, after the base station sends the semi-static RRC signaling for notifying the UE of the current resource scheduling manner to the base station receives the configuration acknowledgement completion signaling returned by the UE, and after the base station receives the configuration acknowledgement completion signaling returned by the UE, if the length of the PDCCH signaling in the DCI format 0 or DCI format 1A of the CIF is not included in the CSS of the current carrier used to carry the PDCCH signaling in the UE is equal to the length of the PDCCH signaling in another format including the CIF in the UESS of the UE used to schedule another carrier having a bandwidth smaller than that of the current carrier on the current carrier, and there is a physical overlapping region between the CSS and the UESS, the base station sends the PDCCH signaling including the CIF in the physical overlapping region, and the signaling carries resource allocation information for the UE. In one embodiment, the UE may negotiate with the base station in advance, and the CIF is included in PDCCH signaling sent in the physical overlapping area. Then, after receiving the PDCCH signaling, the UE may determine that the PDCCH signaling must include CIF, and may determine, according to the CIF in the PDCCH signaling, which carrier the allocated resource is on, so that the UE may not parse the resource incorrectly.

The first search space may be a CSS, the second search space is a UE-specific UESS, and CCE ranks of the first search space and the second search space are 4 or 8. Alternatively, the first search space and the second search space include two UESSs for scheduling different component carriers of the UE.

In one embodiment, there is provided a base station comprising:

a fourth determining module, configured to determine locations of the first search space and the second search space of the UE;

a fourth sending module, configured to, after the first determining module determines the positions of the first search space and the second search space of the UE, send, in the physical overlapping area, PDCCH signaling including a carrier indicator field CIF to the UE or send, in the physical overlapping area, PDCCH signaling not including a CIF to the UE when the PDCCH signaling length not including the CIF in the first search space is equal to the PDCCH signaling length including the CIF in the second search space, and the first search space and the second search space have the physical overlapping area.

In one embodiment, a user equipment UE is provided, comprising:

a fourth receiving module, configured to receive, in a first search space, a PDCCH signaling length that does not include a carrier indicator field CIF and is equal to a PDCCH signaling length that includes a CIF in a second search space, and in a physical overlapping area between the first search space and the second search space, a PDCCH signaling that includes the CIF and is sent by a base station or a PDCCH signaling that does not include the CIF and is sent by the base station in the physical overlapping area;

and the fourth analysis module is used for analyzing the PDCCH signaling received by the receiving module according to the set rule.

Those of ordinary skill in the art will understand that: all or part of the steps for implementing the method embodiments may be implemented by hardware related to program instructions, and the program may be stored in a computer readable storage medium, and when executed, the program performs the steps including the method embodiments; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. An apparatus, comprising:

means for determining locations of a first search space and a second search space of a user equipment, UE;

a module configured to send, in the physical overlapping area, only a PDCCH signaling including a carrier indicator field CIF to the UE if a PDCCH signaling length of a physical downlink control channel that does not include the CIF in the first search space is equal to a PDCCH signaling length that includes the CIF in the second search space, and the first search space and the second search space have the physical overlapping area;

2. The apparatus of claim 1, wherein there is a physical overlap region in the first search space and the second search space, comprising:

the first search space and the second search space comprise at least one Control Channel Element (CCE) with the same label, and the at least one CCE with the same label is the physical overlapping area.

3. An apparatus, comprising:

a module configured to receive, in a physical overlapping area, a PDCCH signaling that only includes a carrier indicator field CIF and is sent by a base station if a PDCCH signaling length that does not include the CIF in a first search space is equal to a PDCCH signaling length that includes the CIF in a second search space, and the first search space and the second search space have the physical overlapping area;

the PDCCH signaling module is used for analyzing the PDCCH signaling module only comprising the CIF according to a set rule;

4. The apparatus of claim 3, wherein there is a physical overlap region between the first search space and the second search space, comprising:

determining that the first search space and the second search space comprise at least one Control Channel Element (CCE) with the same label, wherein the at least one CCE with the same label is the physical overlapping area.