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US-12621195-B2 - Base station and communication method

US12621195B2US 12621195 B2US12621195 B2US 12621195B2US-12621195-B2

Abstract

A base station includes: an allocating circuit that allocates, to a resource set which is monitored by a terminal belonging to a group, a first control signal which contains information indicating the configuration of a slot and a second control signal which does not contain the information indicating the configuration of a slot; and a transmitter that transmits the first control signal and the second control signal to a terminal. The number of symbols to which the first control signal is allocated is made equal to the smallest number of symbols to which the second control signal is allocated.

Inventors

  • Ayako Horiuchi
  • Hidetoshi Suzuki

Assignees

  • PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA

Dates

Publication Date
20260505
Application Date
20220118
Priority Date
20170322

Claims (20)

  1. 1 . A communication apparatus, comprising: circuitry, which, in operation, generates a group common physical downlink control channel (PDCCH) signal; and a transmitter, which is coupled to the circuitry and which, in operation, transmits the group common PDCCH signal, wherein, the group common PDCCH signal is directed to a group of user equipment (UEs), a number of symbols to which the group common PDCCH signal is allocated equals a number of symbols to which another PDCCH signal is allocated, the another PDCCH signal is directed to a UE, the group common PDCCH signal and the another PDCCH signal are mapped to the same control resource set, and the number of symbols to which the group common PDCCH signal is allocated is variable and configured by a higher layer signaling.
  2. 2 . The communication apparatus according to claim 1 , wherein the group common PDCCH signal and the another PDCCH signal are allocated in a time direction first before a frequency direction in the same control resource set.
  3. 3 . The communication apparatus according to claim 1 , wherein the group common PDCCH signal is allocated first in a slot.
  4. 4 . The communication apparatus according to claim 1 , wherein the higher layer signaling indicates a slot in which the group common PDCCH signal is allocated.
  5. 5 . The communication apparatus according to claim 1 , wherein the higher layer signaling indicates the same control resource set to which the group common PDCCH signal is mapped.
  6. 6 . The communication apparatus according to claim 1 , wherein the group common PDCCH signal indicates a number of downlink symbols, a number of uplink symbols, and a number of other symbols.
  7. 7 . The communication apparatus according to claim 1 , wherein the group common PDCCH signal is control information indicating a slot format.
  8. 8 . The communication apparatus of claim 1 , wherein the circuitry, in operation, sets the number of symbols allocated to the group common PDCCH to be equal to the number of symbols allocated to the another PDCCH.
  9. 9 . The communication apparatus of claim 8 , wherein the circuitry, in operation, sets a number of resource element groups (REGs) allocated to the group common PDCCH to be equal to a number of REGs allocated to the another PDCCH.
  10. 10 . A communication method implemented by a communication apparatus, the communication method comprising: generating a group common physical downlink control channel (PDCCH) signal; and transmitting the group common PDCCH signal, wherein, the group common PDCCH signal is directed to a group of user equipment (UEs), a number of symbols to which the group common PDCCH signal is allocated equals a number of symbols to which another PDCCH signal is allocated, the another PDCCH signal is directed to a UE, the group common PDCCH signal and the another PDCCH signal are mapped to the same control resource set, and the number of symbols to which the group common PDCCH signal is allocated is variable and configured by a higher layer signaling.
  11. 11 . The communication method according to claim 10 , wherein the group common PDCCH signal and the another PDCCH signal are allocated in a time direction first before a frequency direction in the same control resource set.
  12. 12 . The communication method according to claim 10 , wherein the group common PDCCH signal is allocated first in a slot.
  13. 13 . The communication method according to claim 10 , wherein the higher layer signaling indicates a slot in which the group common PDCCH signal is allocated.
  14. 14 . The communication method according to claim 10 , wherein the higher layer signaling indicates the same control resource set to which the group common PDCCH signal is mapped.
  15. 15 . The communication method according to claim 10 , wherein the group common PDCCH signal indicates a number of downlink symbols, a number of uplink symbols, and a number of other symbols.
  16. 16 . The communication method according to claim 10 , wherein the group common PDCCH signal is control information indicating a slot format.
  17. 17 . A user equipment (UE), comprising: a receiver, which, in operation, receives: a group common physical downlink control channel (PDCCH) directed to a group of user equipment (UEs); and another PDCCH directed to the UE; and circuitry coupled to the receiver, wherein the control circuitry, in operation, decodes the group common PDCCH and the another PDCCH, wherein, a number of symbols to which the group common PDCCH is allocated equals a number of symbols to which the another PDCCH signal is allocated, the group common PDCCH signal and the another PDCCH are mapped to the same control resource set, and the number of symbols to which the group common PDCCH is allocated is variable and configured by higher layer signaling.
  18. 18 . The user equipment of claim 17 , wherein the circuitry, in operation, sets the number of symbols allocated to the group common PDCCH to be equal to the number of symbols allocated to the another PDCCH.
  19. 19 . The user equipment of claim 18 , wherein the circuitry, in operation, sets a number of resource element groups (REGs) allocated to the group common PDCCH to be equal to a number of REGs allocated to the another PDCCH.
  20. 20 . The user equipment according to claim 17 , wherein the group common PDCCH and the another PDCCH are allocated in a time direction first before a frequency direction in the same control resource set.

Description

TECHNICAL FIELD The present disclosure relates to base stations and communication methods. BACKGROUND ART A communication system called a fifth-generation mobile communication system (5G) has been studied. In 5G, flexible provision of a function to each of the use cases in which an increase in communication traffic, an increase in the number of terminals to be connected, high reliability, and low latency are respectively required has been studied. As representative use cases, there are three use cases: enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra reliable and low latency communicantions (URLLC). 3GPP (3rd Generation Partnership Project), which is the international standard-setting organization, has studied sophistication of a communication system from the aspects of both sophistication of the LTE system and New RAT (radio access technology) (see, for example, NPL 1). CITATION LIST Non Patent Literature NPL 1: RP-161596, “Revision of SI: Study on New Radio Access Technology”, NTT DOCOMO, September 2016 SUMMARY OF INVENTION In New RAT, as a control signal for notifying a terminal of the configuration of a slot, a group common PDCCH (physical downlink control channel) has been studied, and there is a need to study the specific placement of this control signal in radio resources. An aspect of the present disclosure facilitates providing a base station and a communication method which appropriately place a common control signal, which notifies a terminal of the configuration of a slot, in radio resources. A base station according to an aspect of the present disclosure includes: an allocating circuit that allocates, to a resource set which is monitored by a terminal belonging to a group, a first control signal which contains information indicating the configuration of a slot and a second control signal which does not contain the information; and a transmitter that transmits the first control signal and the second control signal to a terminal. The number of symbols to which the first control signal is allocated is made equal to the smallest number of symbols to which the second control signal is allocated. A communication method according to an aspect of the present disclosure is a communication method including: allocating, to a resource set which is monitored by a terminal belonging to a group, a first control signal which contains information indicating the configuration of a slot and a second control signal which does not contain the information; and transmitting the first control signal and the second control signal to a terminal. The number of symbols to which the first control signal is allocated is made equal to the smallest number of symbols to which the second control signal is allocated. It is to be noted that these comprehensive or specific aspects may be implemented by a system, a device, a method, an integrated circuit, a computer program, or a recording medium, or may be implemented by any combination of a system, a device, a method, an integrated circuit, a computer program, and a recording medium. Advantageous Effects of Invention According to an aspect of the present disclosure, it is possible to appropriately place a common control signal, which notifies a terminal of the configuration of a slot, in radio resources. Additional advantages and effects in an aspect of the present disclosure will become apparent from the description and drawings. Although these advantages and/or effects are individually provided by features described in some embodiments and the description and drawings, all of them do not necessarily have to be provided to obtain one or more identical features. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 explains a group common PDCCH according to a first embodiment. FIG. 2A explains the placement of the group common PDCCH. FIG. 2B explains the placement of the group common PDCCH. FIG. 3 depicts the configuration of part of a base station according to the first embodiment. FIG. 4 depicts the configuration of the base station according to the first embodiment. FIG. 5 depicts the configuration of a terminal according to the first embodiment. FIG. 6 shows a PDCCH design operation example of the base station. FIG. 7A explains the relationship between a PDCCH and a CCE. FIG. 7B explains the relationship between the PDCCH and the CCE. FIG. 7C explains the relationship between the PDCCH and the CCE. FIG. 8A explains a configuration example of the PDCCH when an aggregation level is “2”. FIG. 8B explains a configuration example of the PDCCH when the aggregation level is “2”. FIG. 8C explains a configuration example of the PDCCH when the aggregation level is “2”. FIG. 9 explains Case 1). FIG. 10 explains Case 2). FIG. 11 explains Case 3). FIG. 12 explains a design example of the group common PDCCH according to a second embodiment. FIG. 13 explains an example of the number of symbols which are allocated to the group common PDCCH according to a third embodimen