Content for TS 37.213 Word version: 18.1.0
1 Scope
2 References
3 Definitions of terms, symbols and abbreviations
4 Channel access procedure
4.0 General
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1 Scope p. 6
The present document specifies and establishes the characteristics of the physical layer procedures for shared spectrum channel.
2 References p. 6
The following documents contain provisions which, through reference in this text, constitute provisions of the present document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.
[1]
TR 21.905: "Vocabulary for 3GPP Specifications".
[2]
TS 36.104: "Evolved Universal Terrestrial Radio Access (E-UTRA); Base Station (BS) radio transmission and reception".
[3]
TS 36.101: "Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception".
[4]
TS 36.213: "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures".
[5]
TS 36.212: "Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding".
[6]
TS 38.104: "NR; Base Station (BS) radio transmission and reception".
[7]
TS 38.213: "NR; Physical layer procedures for control".
[8]
TS 38.214: "NR; Physical layer procedures for data".
[9]
TS 38.300: "NR; NR and NG-RAN Overall Description; Stage 2".
[10]
TS 38.212: "NR; Multiplexing and channel coding".
[11]
TS 38.211: "NR; Physical channels and Modulations".
3 Definitions of terms, symbols and abbreviations p. 6
3.1 Terms p. 6
For the purposes of the present document, the terms and definitions given in TR 21.905 apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905.
3.2 Symbols p. 6
For the purposes of the present document, the following symbols apply:
CWp
Contention window for a given priority class
CWmax,p
Maximum contention window for a given priority class
CWmin,p
Minimum contention window for a given priority class
Tmcot,p
Maximum channel occupancy time for a given priority class
Tulmcot,p
Maximum Uplink channel occupancy time for a given priority class
XThresh
Energy detection threshold
XThresh_max
Maximum energy detection threshold
3.3 Abbreviations p. 7
For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905.
AUL-DFI
Autonomous UL Downlink feedback indication
CAPC
Channel access priority class
COT
Channel Occupancy Time
LAA
Licensed Assisted Access
MCOT
Maximum Channel Occupancy Time
4 Channel access procedure p. 7
4.0 General |R16| p. 7
Unless otherwise noted, the definitions below are applicable for the following terminologies used in this specification:
- A channel refers to a carrier or a part of a carrier consisting of a contiguous set of resource blocks (RBs) on which a channel access procedure is performed in shared spectrum.
- A channel access procedure is a procedure based on sensing that evaluates the availability of a channel for performing transmissions. The basic unit for sensing is a sensing slot with a duration Tsl=9μs. The sensing slot duration Tsl is considered to be idle if an eNB/gNB or a UE senses the channel during the sensing slot duration, and determines that the detected power for at least 4μs within the sensing slot duration is less than energy detection threshold XThresh. Otherwise, the sensing slot duration Tsl is considered to be busy.
- A channel occupancy refers to transmission(s) on channel(s) by eNB/gNB/UE(s) after performing the corresponding channel access procedures in this clause.
- A Channel Occupancy Time refers to the total time for which eNB/gNB/UE and any eNB/gNB/UE(s) sharing the channel occupancy perform transmission(s) on a channel after an eNB/gNB/UE performs the corresponding channel access procedures described in this clause. For determining a Channel Occupancy Time, if a transmission gap is less than or equal to 25μs, the gap duration is counted in the channel occupancy time. A channel occupancy time can be shared for transmission between an eNB/gNB and the corresponding UE(s).
- A DL transmission burst is defined as a set of transmissions from an eNB/gNB without any gaps greater than 16μs. Transmissions from an eNB/gNB separated by a gap of more than 16μs are considered as separate DL transmission bursts. An eNB/gNB can transmit transmission(s) after a gap within a DL transmission burst without sensing the corresponding channel(s) for availability.
- A UL transmission burst is defined as a set of transmissions from a UE without any gaps greater than 16μs. Transmissions from a UE separated by a gap of more than 16μs are considered as separate UL transmission bursts. A UE can transmit transmission(s) after a gap within a UL transmission burst without sensing the corresponding channel(s) for availability.
-
A discovery burst refers to a DL transmission burst including a set of signal(s) and/or channel(s) confined within a window and associated with a duty cycle. The discovery burst can be any of the following:
- Transmission(s) initiated by an eNB that includes a primary synchronization signal (PSS), secondary synchronization signal (SSS) and cell-specific reference signal(s)(CRS) and may include non-zero power CSI reference signals (CSI-RS).
- Transmission(s) initiated by a gNB that includes at least an SS/PBCH block consisting of a primary synchronization signal (PSS), secondary synchronization signal (SSS), physical broadcast channel (PBCH) with associated demodulation reference signal (DM-RS) and may also include CORESET for PDCCH scheduling PDSCH with SIB1, and PDSCH carrying SIB1 and/or non-zero power CSI reference signals (CSI-RS).
