TR 37.877
Rel-18 downlink interruption for NR and EN-DC band combinations
at dynamic Tx switching
V18.0.0 (Wzip)
2023/12 11 p.
- Rapporteur:
- Mr. Liu, Bo
Chinatelecom Cloud
Content for TR 37.877 Word version: 18.0.0
1 Scope
2 References
3 Definitions of terms, symbols and abbreviations
4 Background
5 Specific Band Combinations
6 Release Independent Requirements
A Common UE RF requirements
$ Change history
1 Scope p. 6
The present document is a technical report for WI "Rel-18 downlink interruption for NR and EN-DC band combinations at dynamic Tx Switching in Uplink" under Rel-18 time frame. The purpose is to gather the relevant background information and studies in order to address the band combinations requested for mandating no DL interruption to conduct dynamic Tx switching in uplink listed in Table 1-1.
| Configuration | Uplink configuration |
|---|---|
| CA_n1-n5-n78 | CA_n1-n78, CA_n5-n78 |
| CA_n3-n5-n78 | CA_n3-n78, CA_n5-n78 |
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 38.101-1: NR; User Equipment (UE) radio transmission and reception; Part 1: Range 1 Standalone
[3]
TS 38.133: "NR; Requirements for support of radio resource management".
[4]
TS 38.101-3: "NR; User Equipment (UE) radio transmission and reception; Part 3: Range 1 and Range 2 Interworking operation with other radios".
3 Definitions of terms, symbols and abbreviations p. 6
3.1 Terms p. 6
For the purposes of the present document, the terms given in TR 21.905 and the following 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:
3.3 Abbreviations p. 6
4 Background p. 7
At 3GPP RAN#96 meeting, a new basket Work Item "Rel-18 downlink interruption for NR and EN-DC band combinations at dynamic Tx Switching in Uplink" was approved. The objectives are as following,
For the core part:
-
Discuss and specify inter-band uplink CA and EN-DC combinations for which DL interruption is not allowed when dynamic switching between two uplink carriers is conducted.
- Based on the requested band combinations from operators, analyze if it is feasible to specify no DL interruption in RAN4 specification.
- Based on the feasibility analysis for specific combination, decide to introduce no DL interruption in RAN4 specification.
- For 2CC 1Tx-2Tx switching, the mandating of no DL interruption for new band combinations is release independent from Rel-16.
- For 3CC 1Tx-2Tx switching and 2CC or 3CC 2Tx-2Tx switching, the mandating of no DL interruption for new band combinations is release independent from Rel-17.
4.1 TR Maintenance p. 7
A single company is responsible for introducing all approved TPs in the current TR, i.e. TR editor. However, it is the responsibility of the contact person of each band/band combination to ensure that the TPs related to the band/band combination have been implemented.
5 Specific Band Combinations p. 7
5.1 NR band combinations p. 7
5.1.1 CA_n1-n5-n78 p. 7
5.1.1.1 Configurations p. 7
| Configuration | Uplink configuration |
|---|---|
| CA_n1-n5-n78 | CA_n1-n78, CA_n5-n78 |
5.1.1.2 Technical analysis p. 7
For CA_n1-n78 and CA_n5-n78, no DL interruption allowed has been specified as mandated in 38101-1, which means switching from n1/n5 to n78 has no impact to n1/n5 downlink. Thus there is no DL interruption for CA_n1-n5-n78 with CA_n1-n78 or CA_n5-n78 uplink configuration when conducting dynamic Tx switching.
5.1.1.3 Conclusion p. 7
No DL interruption for CA_n1-n5-n78 with CA_n1-n78 or CA_n5-n78 uplink configuration is mandated.
| NR CA Band | NR Band
(Table 5.2-1) |
DL interruption allowed (Note 3) |
|---|---|---|
| CA_n1-n5-n78 | n1, n5, n78 | No for CA_n1-n78, CA_n5-n78 |
|
NOTE 4:
Applicable when dynamic Tx switching is conducted. The DL interruption requirement is specified in clause 8.2.2.2.10 of TS 38.133.
|
||
5.1.2 CA_n3-n5-n78 p. 8
5.1.2.1 Configurations p. 8
| Configuration | Uplink configuration |
|---|---|
| CA_n3-n5-n78 | CA_n3-n78, CA_n5-n78 |
5.1.2.2 Technical analysis p. 8
For CA_n3-n78 and CA_n5-n78, no DL interruption allowed has been specified as mandated in 38101-1, which means switching from n3/n5 to n78 has no impact to n3/n5 downlink. Thus there is no DL interruption for CA_n3-n5-n78 with CA_n3-n78 or CA_n5-n78 uplink configuration when conducting dynamic Tx switching.
5.1.2.3 Conclusion p. 8
No DL interruption for CA_n3-n5-n78 with CA_n3-n78 or CA_n5-n78 uplink configuration is mandated.
| NR CA Band | NR Band
(Table 5.2-1) |
DL interruption allowed (Note 3) |
|---|---|---|
| CA_n3-n5-n78 | n1, n5, n78 | No for CA_n3-n78, CA_n5-n78 |
|
NOTE 4:
Applicable when dynamic Tx switching is conducted. The DL interruption requirement is specified in clause 8.2.2.2.10 of TS 38.133.
|
||
6 Release Independent Requirements p. 8
The mandating of no DL interruption requirement belongs to the feature of inter-band CA or EN-DC with tx switching. Thus to specify the release independent requirement shall involve the feature of tx switching. The specific requirements need to be fulfilled include downlink interruption requirement, mandating no DL interruption requirement and time mask requirements as specified in the TS 38.133 and TS 38.101-1. Because RRM downlink interruption requirement is referred when specifying mandating no DL interruption in TS 38.101-1, only UE RF requirements are listed in the last column of the Table in the clause 6.1 and 6.2, which are the requirements to be fulfilled by inter-band CA or EN-DC to support tx switching feature.
6.1 Inter-band CA p. 8
Requirements for a Rel-16 UE for additional NR inter-band CA configurations within FR1 compared to TS 38.101-1 of Rel-16 are introduced via this clause.
Requirements for a Rel-17 UE for additional NR inter-band CA configurations within FR1 compared to TS 38.101-1 of Rel-17 are introduced via this clause.
| Feature | DL/UL | Maximum number of bands | number of CCs | CA BW Classes | Duplex-mode | Release independent from | requirements to be fulfilled (see 38.307 of the REL in which the CA configuration was introduced) |
|---|---|---|---|---|---|---|---|
| Inter-band CA configurations with 1Tx-2Tx switching within NR FR1 | UL | 2 | 2 | A | TDD, FDD and TDD | Rel-16 | Table A.2-1 |
| Inter-band CA configurations with 1Tx-2Tx switching within NR FR1 | UL | 2 | 3 | A, B, C | TDD, FDD and TDD | Rel-17 | Table A.2-1 |
| Inter-band CA configurations with 2Tx-2Tx switching within NR FR1 | UL | 2 | 2 | A | TDD, FDD and TDD | Rel-17 | Table A.2-1 |
| 2 | 3 | A, B, C |
6.2 Inter-band EN-DC p. 9
Requirements for a Rel-16 UE for additional EN-DC inter-band configurations within FR1 compared to TS 38.101-3 of Rel-16 are introduced via this clause.
| Feature | DL/UL | maximum number of E-UTRA bands | maximum number of E-UTRA CCs | maximum number of NR bands | maximum number of NR CCs | Duplex-mode | Release independent from | requirements to be fulfilled (see 38.307 of the REL in which the CA configuration was introduced) |
|---|---|---|---|---|---|---|---|---|
| Inter-band EN-DC with 1Tx-2Tx switching | UL | 1 | 1 | 1 | 1 | TDD, FDD and TDD | Rel-16 | Table A.1-1 |
A Common UE RF requirements p. 9
A.1 Common UE RF requirements for Inter-band EN-DC with tx switching p. 9
The requirements and test cases listed in Table A.1-1 are specified in in REL-16 version of TS 38.101-3.
| Clause | Description |
|---|---|
| 5.5B.4 | Configuration for Inter-band EN-DC within FR1 |
| 6.3B.4 | Output power dynamics for switching between two uplink carriers |
A.2 Common UE RF requirements for Inter-band CA configurations with tx switching within NR FR1 p. 10
The requirements and test cases listed in Table A.2-1 are specified in Rel-16 version of TS 38.101-1.
The requirements and test cases listed in Table A.2-1 are specified in Rel-17 version of TS 38.101-1.
| Clause | Description |
|---|---|
| 5.2A.2 | Operating bands for inter-band CA |
| 6.3A.3.3 | Transmit ON/OFF time mask for inter-band CA |
$ Change history p. 11
