Deep Dive 5G NR-RAN Release 2018 Q4 Swisscom - L1 & RM.pdf

Deep Dive 5G NR-RAN Release 2018 Q4 | Commercial in confidence | 6/2882-560/FCP 131 5500 Uen, Rev PC25 | 2018-05-30 | Page 1
5G NR-RAN Deep Dive
2018 Q4 release

L1&RRM

TableofContents
— NR Numerology, Frame structure, NR cell
— Downlink Channels and Signals
— Uplink Channels and Signals
— Scheduling
— Link Adaptation
— L2- PDCP, RLC, MAC
— NR SU-MIMO Digital Beamforming
— Energy Performance Feature
— Abbreviations

NR–BasicNumerology
— LTE: A single 15 kHz subcarrier spacing
— Normal and extended cyclic prefix
— NR supports sub-1GHz to several 10 GHz spectrum range
 Multiple OFDM numerologies required
— Flexible subcarrier spacing always a factor of 15kHz where n varies
from 0 to 4 ( Δf=2n∙15 kHz )
— Scaled from LTE numerology
— Higher subcarrier spacing  Shorter symbols and
cyclic prefix
— Extended cyclic prefix only standardized for 60 kHz
Data [kHz] SSB [kHz]
< 6 GHz 15, 30, 60 15, 30
> 6 GHz 60, 120 120, 240
Notes: 30 kHz subcarrier spacing is supported for < 6 GHz
frequency bands in 18.Q4 for both data and SSB.
Rel-15 supports the following numerologies
15 kHz 30 kHz 60 kHz 120 kHz 240 kHz

Low frequency
Low-medium
frequency
(Optimized CP)
60 kHz, ECP mmW
Subcarrier spacing 15 kHz 30 kHz 60 kHz 120 kHz
Slot duration 1000 µs 500 µs 250 µs 125 µs
Slot illustration
OFDM symbol, duration 66.67 µs 33.33 µs 16.67 µs 8.33 µs
Cyclic prefix, duration 4.69 µs 2.34 µs 4.17 µs 0.59 µs
OFDM symbol including
cyclic prefix
71.35 µs 35.68 µs 20.83 µs 8.92 µs
Max carrier bandwidth
(assuming 4k FFT)
50 MHz 100 MHz 200 MHz 400 MHz
NR-Numerology(Data)
› 30 kHz subcarrier spacing is supported in 18.Q4 for FR1 (< 6 GHz)

TDDFrameStructure
— NR supports FDD, dynamic TDD, and TDD with semi-statically configured UL/DL
configuration:
— TDD pattern supported in 18.Q4 is: 3 DL slots and 1 UL slot with guard period in a slot where DL
symbols are followed by UL symbols.
— DL/UL assignment is communicated to UE through RRC signalling.
n+3
n+1
n n+2 n+4
C D D D D D D D D D D D D D C D D D D D D D D D D
C D D D D D D D D D D D D D
PUSCH/DMRS
D
PUCCH
C
PDCCH
C
PDSCH/DMRS
D
GP
D D D D D D D D
D D D D D D
C C

NRCellandBWP
— NR Cell
— Defined by the (same) SS Block information
— Supports cell Bandwidth of 20 / 100 MHz in 18.Q4
(40 / 60 /80 MHz will be supported in 19.Q1)
— Bandwidth Parts (BWP)
— A BWP is associated with a numerology, PXCCH, PXSCH,
and DM-RS within a BWP share the same numerology.
— A UE is limited to a single active BWP at a time.
— In 18.Q4, BWP is equivalent to cell bandwidth.
— Within each BWP a CORESET is configured for the UE to
monitor the PDCCH.
SS1 SS2
NR Cell
UE BW = Cell BW
BWP
Overall carrier

Downlink Channels and
Signals

SS/PBCHBlock
— The synchronization signal and PBCH block (SSB) consists of Primary
Synchronization Signal (PSS), Secondary Synchronization Signal (SSS),
and PBCH.
— Uses 4 consecutive OFDM symbols.
— Transmitted every 5 / 10 / 20 / 40 / 80 / 160 ms.
— SSB periodicity is configured in RRC parameter, default to 20ms in
18.Q4
— Numerology of SSB depends on frequency band.
— 30KHz subcarrier spacing is supported in 18.Q4
— Time locations where SSB can be sent are determined by sub-carrier
spacing.
— Polar coding is used for PBCH.
— NR cell search is based on the primary and secondary synchronization
signals, and PBCH DMRS
— UE performs matched filtering to find PSS.
— UE detects SSS in the frequency domain.
— PSS and SSS together indicate physical Cell ID (in total
3*336 = 1008 physical Cell IDs).
— UE decodes MIB contained in PBCH. MIB is transmitted in PBCH with
periodicity of 80ms.
— System Frame Number (SFN)
— Subcarrier spacing for initial access
— SSB Subcarrier Offset
— DMRS TypeA Position
frequency
symbols
PBCH
PBCH
SSS
PSS
PBCH
PBCH
127
subcarriers
240
subcarriers
SSB periodicity = 20ms (default)
slots
5ms

PDCCH–Configurations(1/2)
— Control-resource set (CORESET)
— A CORESET is a subset of the downlink physical resource
configured to carry control signaling (PDCCH).
— For the slot-based (Type A) scheduling, the CORESET is
located at the beginning of a slot.
— The REs in a CORESET are organized in Resource Elements
Groups (REGs). Each REG consists of 12 REs of one OFDM
symbol in one RB.
— Allocation in the frequency domain is done in units of 6 REGs.
— PDCCH
— A PDCCH is confined to one CORESET with aggregation level
of up to 16 control channel elements(CCE).
— Supported aggregation level depends on the CORESET
size and cell bandwidth.
— REG bundling and precoding granularity
— The REGs can be configured to form REG bundles. REG
bundle size depends on CORESET length in time.
— REG bundle size of 6 is supported in 18.Q4.
— Polar coding is used for PDCCH.
DM-RS
Data
Data
Data
…
Data
Data
PDCCH
PDSCH
CORESET
DM-RS

PDCCH–Configurations(2/2)
— PDCCH DMRS
— DMRS is mapped on all REGs on all the OFDM symbols for a given PDCCH candidate.
— Search spaces
— A PDCCH candidate is a set of control channel elements(CCE) in which a UE may expect to
receive a PDCCH of a certain DCI format.
— A search space is a set of PDCCH candidates monitored by a single UE or several UEs.
— A UE-specific search space is monitored by a single UE.
— A common search space may be monitored by several UEs.
— Search space is configured by RRC signaling.
— PDCCH blind decoding
— A UE shall attempt to blindly decode all its PDCCH candidates in all assigned search spaces.

PDSCH(1/2)
— DL transport block is carried by PDSCH
— A transport block is mapped to one carrier.
— LDPC coding is used.
— The following modulation orders are supported: QPSK, 16QAM, 64QAM and 256QAM.
— Single transmission scheme for PDSCH
— UEs can receive 1–4 MIMO layers.
— Implementation enables beamforming and/or transmit diversity schemes.
— PDSCH DM-RS
— Type 1 with up to 4 DM-RS ports is supported.
— For slot-based mapping (Type A), a UE is configured with the first front-loaded DM-RS in the third
symbol of the slot, and in addition, it will be configured with 1 or 2 additional DM-RSs.

PDSCH(2/2)
—Resource allocation
— Same-slot scheduling: PDCCH and the scheduled PDSCH have the same
numerology.
— Resource allocation in the frequency domain are supported by semi-static
configuration:
— Type 0: Bitmap of RBGs. RBG size (4, 8, or 16 RBs) is determined by BWP size
and RRC configuration. Configuration 1 is supported.
— Resource allocation in the time domain
— Slot-based mapping (Type A) is supported.
—PRB bundling
— Precoding Resource Block Group (PRG) of wideband are supported.
— Configured by higher layer

ChannelStateInformationReference
Signal(CSI-RS)
— Channel state information reference signal (CSI-RS) was first introduced in LTE release 10 to support
transmission mode 9 with up to 8 layers.
— CSI-RS evolved substantially over the releases to support more functionalities, especially in NR.
— CSI-RS are needed for the following NR functionalities:
— Link adaptation
— Codebook-based DL precoding
— Non-codebook based DL precoding
— Tracking reference signals (TRS) for frequency/time tracking
— Radio link monitoring (RLM)

TRS(1/2)
— Unlike LTE, NR does not have CRS; hence, TRS is introduced for fine time-frequency tracking.
— Tracking reference signals (TRS) is configured by UE specific RRC signaling as a set of CSI-RS resources
with setting higher layer parameter TRS-INFO to “true”.
— For FR1, the UE may be configured with a CSI-RS resource set of four periodic CSI-RS resources in two
consecutive slots with two CSI-RS resources in each slot.
— For each CSI-RS resource, it’s configured by CSI-RS-ResourceMapping with below restrictions:
— The OFDM symbol indices of the two CSI-RS resources in a slot is given by one of (4,8), (5,9) or
(6,10).
— For each CSI-RS resource
— One-port
— Density = 3
— The bandwidth is UE BWP, and in units of 4.
— The periodicity is one of 10, 20, 40, or 80ms.
— Same pattern is applied for two slots
— TRS is transmitted independent of PDSCH transmission.
— Power boosting of TRS could be supported by configuring 1~3 ZP CSI-RS resources.

TRS(2/2)
— All the UE shall be configured with the same TRS resource within the cell.
— Only one periodic TRS resource is supported and configured for each UE.
— The periodicity of TRS can be configured per cell through MOM attribute.
— Set to 40ms by default.
— The time domain location (symbol index within one slot) is fixed to (4,8).
— Different power boosting level can be configured per cell.
— TRS slot offset
— No colliding with RA Msg2 as much as possible
— No colliding with SSB/PBCH slot

TRSFormat
*one slot is only
supported for
> 6 GHz
CSI-RS resource #1
CSI-RS resource #2
CSI-RS resource #3
CSI-RS resource #4
— An example of TRS format is illustrated:

CSI-RSResource
— Non-zero-power CSI-RS resources
— Used for DL channel measurement
— Periodic CSI-RS resource configuration will be supported.
— The periodicity of NZP CSI-RS is configured per cell.
— UE is configured with the same Non-zero-power CSI-RS resource within the cell. (*)
— Only one NZP CSI-RS resource set is configured for UE to measure DL channel.
— CSI-Interference Management (CSI-IM) resources
— It’s configured for UE to measure DL inter-cell interference.
— Only one periodic CSI-IM resource is configured for DL inter-cell interference measurement.
— The periodicity is the same as NZP CSI-RS
— The frequency band is the same as that for NZP CSI-RS.
— All the UEs shall be configured with the same CSI-IM resource.
— Zero-power CSI-RS resources
— Used for inter-cell interference measurement and PDSCH rate-matching.
— One Zero-power CSI-RS resource shall be configured as the same location as CSI-IM.
— More ZP CSI-RS will be configured if TRS power boosting is needed.
*Assume UE supports 32-ports CSI-RS

Uplink Channels and
Signals

NRContentionBasedRandomAccess
—NR-NSA uses Dual Connectivity.
— Creation of the UE context in the gNodeB is performed before the random
access procedure is initialized.
— Before the random access procedure to the gNodeB, the UE connects to the
eNodeB through RRC.
— Before the random access procedure, the UE receives a C-RNTI to be used for
the NR leg through RRC signaling that is tunneled over the LTE leg.
—Basic functionality allows scheduling of RA Msg2, Msg3, and
Contention Resolution Message.
—Random access coverage is comparable to that of other NR
channels.

NRRandomAccessProcedure
—The contention-based RA procedure is similar to LTE.
— NR-NSA case: a C-RNTI is assigned to the UE before the RA
procedure.
Msg1
Preamble
Msg3
PUSCH
Time
[slot]
rar-WindowLength ra-ContentionResolutionTimer
> X symbols
Msg2
PDSCH
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Msg2
PDCCH
Contention
resolution
grant
PUSCH

—RA Msg1 - PRACH transmission
— PRACH preamble format B4 with a ZC Sequences of length 139 is chosen.
— The 3GPP defined PRACH configuration table has PRACH configuration
indexes for each preamble format which indicate:
— The periodicity, the PRACH subframe, the number of slots within the PRACH subframe,
the number of time-domain PRACH occasions within the PRACH slot, the start symbol
within the slot, and the PRACH duration in symbols.
— For the first product, a PRACH configuration index with 10ms periodicity
will be configured.
— The same subcarrier spacing is used for PRACH and PUSCH.
— A single PRACH resource is configured, which means that no beam
sweeping is present.

—RA Msg2 – Random Access Response (RAR)
— Transmitted using a DCI on the PDCCH and a PDSCH transmission.
— The RAR contains allocation information for the Msg3 PUSCH
transmission
— A new concept of CORESET is introduced to transmit PDCCH in NR.
— A CORESET is a time/frequency region in which a UE searches for DCI.
— For instance, for a 20 MHz system, a single CORESET of the size of 8 CCEs in the first
symbol is used for both DL and UL DCIs.
— The UE monitors the PDCCH in common and UE-specific search spaces within defined
CORESET(s).
— For RAR, the UE monitors Type1 PDCCH common search space for a DCI scrambled by
the RA-RNTI.

— RA Msg3 - PUSCH transmission
— The UE transmits Msg3 on the PUSCH upon successful RAR reception:
— RAR received within the RAR response window
— Contains RA preamble identifier that matches the transmitted preamble
— Msg3 PUSCH message includes the C-RNTI transmitted in the LTE leg.
— RA Contention Resolution Timer starts after Msg3 is transmitted.
— Contention Resolution Message
— For NR-NSA, the contention resolution message is an UL grant sent on the PDCCH.
— A regular PDCCH transmission is addressed to the C-RNTI of the UE, which
contains an UL grant for a new transmission.
— The UE monitors PDCCH candidates in a UE-specific search space for a DCI format
scrambled by the C-RNTI.
— Reception of the PUSCH transmission (using the contention resolution grant) signifies
that the contention based RA procedure is completed successfully.

PUCCHConfiguration(1/3)
—PUCCH carries HARQ-ACK, SR(scheduling
request)
—Long PUCCH to be configured in one
cell/BWP
—Amount of PUCCH resources will be static
configured after Cell/BWP setup in 18Q4.
— FDM with PUSCH (PRB-based)
— One Pair of PRBs allocated for PUCCH
resources (14 symbols)
— Frequency hopping is enabled
PDCCH
PDCCH
PUCCH
Slot duration
PUSCH
PUCCH PUCCH
PUCCH

—Upon UE connection setup
— Resource sets for DL HARQ-ACK.
— PUCCH format 1 (1 or 2 bits): 3 resources are configured per UE.
— PUCCH format 3 (3+ bits): 1 resource is configured per UE.
— No resource is configured for periodic CSI report.
— Only aperiodic CSI report is supported on PUSCH.
— Every UE is given an SR resource at UE setup
—If a UE would transmit a PUCCH that has a same first symbol and
duration with a PUSCH transmission, the UE multiplexes the UCI in the
PUSCH transmission and does not transmit the PUCCH.

—Periodic SR resource
— Only one SR per UE is configured.
— One SR resource is configured for all UL bearers in one cell.
— All UEs have the same SR periodicity
— SR Periodicity may be configured depending on the numerology.
— For FR1, SR periodicity can be chosen from slots of 20, 40, 80, or 160.
— PUCCH format 1 is configured for SR report.

PUSCH
— UL transport block is carried by PUSCH:
— A transport block is mapped to one carrier, with LDPC coding and CP-OFDM.
— The following modulation orders are supported: QPSK, 16QAM, 64QAM.
— Single transmission scheme for PUSCH:
— Codebook-based, single Tx and 1 layer
— 1 port DMRS
— Resource allocation
— DCI and scheduled PUSCH have an offset of minimum 2 slots.
— Frequency resource allocation Type 1 is supported with semi-static configuration, indicated by
starting virtual RB position and a length of contiguously allocated RBs.
— Resource allocation in the time domain:
— Slot-based mapping Type A is supported.

ChannelCoding
— PDCCH (DCI), PBCH:
— Polar codes
— UCI
— Very short UCI (K<=11 bits): short block codes
— K=1: repetition code
— K=2: simplex code
— 3<=K<=11: LTE Reed-Mueller code
— Longer UCI (K>11 bits): Polar codes
— Include both UCI carried by PUCCH and PUSCH
— PDSCH, PUSCH:
— LDPC codes

Scheduling

BasicNRScheduling
— A few (up to 5) connected UEs are assumed in an NR cell.
— All connected UEs are assumed to support full bandwidth configured for the cell.
— The BWP of UE must be same as the cell bandwidth.
— Each PDSCH/PUSCH transmission requires an explicit DL/UL grant on PDCCH.
— In every time slot, one or both of the following happens:
— Up to one UE is allocated for PDSCH transmission in DL slot
— Up to one UE is allocated for PUSCH transmission in UL slot
— Single User MIMO
— One codeword with up to 4 layers for UE PDSCH transmission.
— Enable Low Energy Scheduler Solution to reduce power consumption by shaping DL traffic data and
increasing blanked subframes when Radio temperature rises.
— TPC for PUCCH, PUSCH and SRS are not supported in first release.

DLUETrafficScheduling
— DCI 1-1 is used for UE PDSCH transmission.
— K0 in “Time domain resource assignment” is 0 (PDSCH is transmitted at the same slot as associated
PDCCH).
— PDSCH-to-HARQ_feedback (K1) values are not smaller than the slot value in “Time domain resource
assignment” (K2) provided in DCI 0-1 for the same UE.
PUSCH/DMRS
D
PUCCH
C
PDCCH
C
PDSCH/DMRS
D
HARQ feedback
PDSCH scheduling
PUSCH scheduling
n+3
n+1
n n+2
C D D D D D D D D D D D D D C D D D D D D D D D D
C D D D D D D D D D D D D D
D D D D D D D D
D D D D D D
n+7
D D D D D D D D
D D D D D D

DLUETrafficScheduling
— Resource allocation type 0 is used for PDSCH resource allocation.
— Resource allocation based on DL data buffer of the UE.
— gNodeB Link Adaptation
— Multiple bearers can be supported.
— Priority scheduling:
— Resource Fair based among all types of bearers
— Adaptive HARQ retransmission.
— Codeword based retransmission

ULUETrafficscheduling
— DCI 0-1 is used for UE PUSCH transmission grant.
— K2 is compliant to 3GPP requirement which is minimum 2 slots
— Resource allocation type 1 is used for PUSCH resource allocation.
— Resource allocation is based on BSR and PHR reports of the UE.
— UL link adaptation is supported
— One layer is transmitted over PUSCH.
— Modulation
— Up to 64QAM
— Adaptive HARQ Retransmission
— Codeword based retransmission
— Multiple bearers can be supported.
— Priority scheduling:
— Resource Fair based among all data bearers.

Link Adaptation

LinkAdaptation
— Link Adaptation (LA) for PDSCH and PUSCH consists of the following:
— Inner loop MCS selector targeting a fixed Block Error Rate (BLER) of 10% for all HARQ
transmissions
— Outer loop channel quality corrector based on HARQ ACK/NACK feedback to enforce the BLER
target
— For PDSCH, CSI reported by UE (CQI, RI) is used as input for LA:
— Aperiodic CSI-RS reporting with wideband CQI
— For PUSCH, signal power and noise-plus-interference is measured in the gNodeB and used as input for
LA, together with UE-reported PHR.

LinkAdaptation
— For PDSCH, a single transport block with up to 4 layers per DL assignment is supported.
— The number of layers follows the UE-reported RI feedback.
— For PUSCH, a single transport block with a single layer per UL assignment is supported.
— TB-based HARQ feedback and retransmission is supported for both PUSCH and PDSCH.
— For PDCCH, a fixed aggregation level is used for all UEs, targeting cell edge coverage.

TransportBlockSizeDetermination(1/2)
Hybrid method is adopted for transport block size
determination:
1. Calculate an intermediate number of information
bits
𝑁𝑖𝑛𝑓𝑜 = 𝜐 ∙ 𝑄𝑚 ∙ 𝑅 ∙ 𝑛𝑃𝑅𝐵 ∙ ത
𝑁𝑅𝐸
′
— 𝜐 is the number of layers
— 𝑄𝑚 is the modulation order, obtained from the
MCS index (Table 5.1.3.1-1 and Table Table
5.1.3.1-2 in TS 38.214)
— 𝑅 is the code rate, obtained from the MCS index
— 𝑛𝑃𝑅𝐵 is the total number of allocated PRBs
determined from DCI
— ത
𝑁𝑅𝐸
′
is the quantized average number of available
REs in an allocated PRB (see next slide)
2. If 𝑁𝑖𝑛𝑓𝑜 ≤ 3824, use a look-up table to determine
TBS (Table 5.1.3.2-2)
3. Otherwise, use a formula to determine TBS
Table 5.1.3.2-2: TBS for 3824
info 
N
Index TBS Index TBS Index TBS Index TBS
1 24 31 336 61 1288 91 3624
2 32 32 352 62 1320 92 3752
3 40 33 368 63 1352 93 3824
4 48 34 384 64 1416
5 56 35 408 65 1480
6 64 36 432 66 1544
7 72 37 456 67 1608
8 80 38 480 68 1672
9 88 39 504 69 1736
10 96 40 528 70 1800
11 104 41 552 71 1864
12 112 42 576 72 1928
13 120 43 608 73 2024
14 128 44 640 74 2088
15 136 45 672 75 2152
16 144 46 704 76 2216
17 152 47 736 77 2280
18 160 48 768 78 2408
19 168 49 808 79 2472
20 176 50 848 80 2536
21 184 51 888 81 2600
22 192 52 928 82 2664
23 208 53 984 83 2728
24 224 54 1032 84 2792
25 240 55 1064 85 2856
26 256 56 1128 86 2976
27 272 57 1160 87 3104
28 288 58 1192 88 3240
29 304 59 1224 89 3368
30 320 60 1256 90 3496

TransportBlockSizeDetermination(2/2)
— To support flexible scheduled durations for PDSCH/PUSCH in NR,
average number of available REs in a PRB ത
𝑁𝑅𝐸
′
is quantized from
𝑋 = 12 ∙ 𝑁𝑠𝑦𝑚𝑏
𝑠ℎ
− 𝑁𝐷𝑀𝑅𝑆
𝑃𝑅𝐵
− 𝑁𝑜ℎ
𝑃𝑅𝐵
according to table on the right
— 𝑁𝑠𝑦𝑚𝑏
𝑠ℎ
is the number of scheduled OFDM symbols
— 𝑁𝐷𝑀𝑅𝑆
𝑃𝑅𝐵
is the number of REs for DM-RS per PRB in the scheduled
duration including the overhead of the DM-RS CDM groups
indicated by DCI format 1_0/1_1
— 𝑁𝑜ℎ
𝑃𝑅𝐵
is the overhead configured by higher layer
— The set of possible 𝑁𝑜ℎ
𝑃𝑅𝐵
values are [0, 6, 12, 18]
— Default value is 0 for both UL and DL
X ഥ
𝑁𝑅𝐸
′
X ≤ 9 6
9<X ≤ 15 12
15<X ≤ 30 18
30<X ≤ 57 42
57<X ≤ 90 72
90<X ≤ 126 108
126<X ≤ 150 144
150<X 156

MCSTableforPDSCHandPUSCH
Table 5.1.3.1-2: MCS index table 2 for PDSCH
MCS Index
IMCS
Modulation Order
Qm
Target code Rate R x [1024] Spectral
efficiency
0 2 120 0.2344
1 2 193 0.3770
2 2 308 0.6016
3 2 449 0.8770
4 2 602 1.1758
5 4 378 1.4766
6 4 434 1.6953
7 4 490 1.9141
8 4 553 2.1602
9 4 616 2.4063
10 4 658 2.5703
11 6 466 2.7305
12 6 517 3.0293
13 6 567 3.3223
14 6 616 3.6094
15 6 666 3.9023
16 6 719 4.2129
17 6 772 4.5234
18 6 822 4.8164
19 6 873 5.1152
20 8 682.5 5.3320
21 8 711 5.5547
22 8 754 5.8906
23 8 797 6.2266
24 8 841 6.5703
25 8 885 6.9141
26 8 916.5 7.1602
27 8 948 7.4063
28 2 reserved
29 4 reserved
30 6 reserved
31 8 reserved
Table 5.1.3.1-1: MCS index table 1 for PDSCH
MCS Index
IMCS
Modulation Order
Qm
Target code Rate R x [1024] Spectral
efficiency
0 2 120 0.2344
1 2 157 0.3066
2 2 193 0.3770
3 2 251 0.4902
4 2 308 0.6016
5 2 379 0.7402
6 2 449 0.8770
7 2 526 1.0273
8 2 602 1.1758
9 2 679 1.3262
10 4 340 1.3281
11 4 378 1.4766
12 4 434 1.6953
13 4 490 1.9141
14 4 553 2.1602
15 4 616 2.4063
16 4 658 2.5703
17 6 438 2.5664
18 6 466 2.7305
19 6 517 3.0293
20 6 567 3.3223
21 6 616 3.6094
22 6 666 3.9023
23 6 719 4.2129
24 6 772 4.5234
25 6 822 4.8164
26 6 873 5.1152
27 6 910 5.3320
28 6 948 5.5547
29 2 reserved
30 4 reserved
31 6 reserved
— Table: 64QAM, use for both PDSCH and PUSCH — Table2: 256QAM, use for PDSCH only

L2- PDCP, RLC, MAC

gNB
UE
3GPP UPprotocolarchitecture(fordata)
SDAP
PDCP
RLC
MAC
SDAP
PDCP
RLC
MAC
NR adds new layer when connected
to 5G-CN, but transparent mode is
assumed for the slides herein.
PHY PHY
IP packet
SDAP PDU
SDAP SDU
PDCP SDU
PDCP SDU
header
PDCP PDU

Details,FormatsinNRPDCP/RLC
— PDCP layer:
— Based on LTE but adapted to the new physical layer of NR:
— DRB support for 18 bits and 12 bits PDCP SN (both applicable for UM and AM)
— UL Reordering
— RLC layer:
— Based on LTE but adapted to the new physical layer of NR:
— Concatenation replaced by Multiplexing by MAC
— Single RLC SDU or segment of same per RLC PDU
— DRB AM support for 12 and 18 bits SN
— Same SN is used for segmented RLC SDU/RLC PDU, SO refers to the bytes of RLC SDU
— AM only: Use NACK Range (and E3) to report losses of multiple adjacent RLC PDUs
— No SO field on the header of a first segment of an SDU

PDCP Data PDU for DRBs
PDCP SDU
Header
Field
Meaning Length
(bits)
SRB
AM
DRB
AM
DRB
UM
D/C Data / Control
flag
1 X X
R Reserved 1 X X X
SN Sequence
Number
12/18 12 12/18 12/18
MAC-I MAC Integrity 32 X option option
D/C R R R R R byte 1
byte 2
byte 3
D/C R R R byte 1
byte 2
SN
SN
SN
or
SN
SN
SDU
• Same header structure as LTE
• 12 or 18 bits SN field (7, 12, 15, 18 in LTE)

• Similar (but not same) header structure as LTE
• 18 or 12 bits SN field (16 or 10 in LTE)
• Just one SDU or one segment per RLC PDU (no concatenation)
• Segmentation of RLC SDU / PDU:
• SI field indicates First and/or/nor Last byte of SDU
• Same SN for a SDU, and all segments
• SO describes the non-zero offset for a neither-nor segment
• Receiver can reassemble RLC SDU by SN, SO, or SI
• RF and LI fields are not used in contrast to LTE
RLC SDU
Header
Field
Meaning Length
(bits)
UM AM
D/C Data / Control flag 1 N/A X
P Poll bit 1 N/A X
SI Segmentation Info* 2 X X
R Reserved 1 X X
SN Sequence Number 18/12 X X
SO Segmentation Offset 16 X X
D/C P R R byte 1
byte 2
byte 3
D/C P R R byte 1
byte 2
byte 3
byte 4
byte 5
SN
SN
SO
SI
SI
SO
SN
or
SN
SN
SN
RLC Data PDU Format - RLC AM PDU (18 Bits SN)
AM PDU (18 bits SN for SDU segment)
AM PDU (18 bits SN for SDU)
SDU

RLC Control PDU Format - STATUS PDU (18 Bits SN)
• Extends RLC status reporting from LTE by adding block NACK reporting.
• E3=1 multiple adjacent SN missing, indicated by NACK range.
• SOstart and SOend appear before NACK range if both are used.
7 6 5 4 3 2 1 0
D/C Oct 1
Oct 2
E1 R Oct 3
Oct 4
Oct 5
E1 E2 E3 R R R Oct 6
Oct 7
Oct 8
Oct 10
Oct 11
Oct 12
Oct 13
Oct 14
Oct 15
Oct 16
Oct 18
…
SOend
SOend
NACK_SN
NACK_SN
SOstart
SOstart
NACK_SN
NACK_SN
NACK_SN
NACK_SN
NACK_SN
ACK_SN
ACK_SN
NACK_SN
CPT
ACK_SN
NACK_SN
NACK range
Header Field Meaning Length
(bits)
D/C Data / Control flag 1
CPT Control PDU type 3
ACK_SN Acknowledgement SN 12/18
E1 1: [NACK_SN,E1,E2,E3] follows 1
E2 1: [SOstart, SOend] follows for this NACK_SN 1
E3 1: NACK Range follows from this NACK_SN 1
NACK_SN SN detected as lost 18/12
NACK range Number of adjacent SNs lost including NACK_SN 8
SOstart Position of First byte of lost portion with NACK_SN 16
SOend Position of Last byte of lost portion with NACK_SN 16
MAC RLC control MAC CE MAC Padding CE
MAC CE
… …
MAC RLC RLC SDU MAC RLC RLC SDU

MAC RLC PDCP Data Unit
MAC Sub-PDU Format for SDU (Service Data Unit)
Header
Field
Meaning Length
(bits)
R Reserved 1
F Format Field 1
LCID Logical Channel Id 6
L Length of data in bytes 8/16
R F=0 byte 1
byte 2
R F=1 byte 1
byte 2
byte 3
LCID for SDU
L
or
L
L
LCID for SDU
SDU • Similar MAC subheader structure as in LTE
• 6 bits LCID field (5 in LTE).
• 1 or 2 bytes Length (L) field in MAC subheader for SDU
• 0, 1 … 32 is used for ‘identity of logical channel’
• 0,1 … 16 in LTE
MAC SDU

MAC SUB-PDU format for CE (Control Element)
• No Length (L) field for fixed size CEs
• 1 or 2 bytes Length (L) field in variable size CEs
• Upper range of LCIDs (63, 62 …) is used for CEs
• In a DL PDU, CEs are placed in front on SDUs
• In a UL PDU, SDUs are placed in front on CEs
• If needed, padding is always placed at the end
R R byte 1
R F=0 byte 1
byte 2
R F=1 byte 1
byte 2
byte 3
L
L
L
LCID for CE (fixed size)
LCID for CE (variable small size)
LCID for CE (variable large size)
MAC CE MAC SDU MAC Padding CE
MAC CE MAC SDU
. . . . . .
UL PDU :
DL PDU :
MAC CE
MAC SDU MAC Padding CE
MAC CE
MAC SDU . . .
. . .
LCID in DL is used for
111000 - 111010 Activation/Deactivation
111101 TAC
111111 Padding
LCID in UL is used for
111000 - 111001 PHR
111011- 111110 BSR
111111 Padding

NR SU-MIMO Digital
Beamforming

Background
— This feature provides beamforming functionality for the NR 64TRX AAS, enabling Full-Dimension
MIMO (FD-MIMO).
— Antenna configuration is 4x8x2.
V
H
2D antenna array
4
rows
8 columns
Subarray with
2-4 x-pol elements

FeatureOverview
— DL cell shaping
— PSS/SSS/PBCH/PDCCH/PDSCH/DMRS
— UL cell shaping and UL SU-MIMO with 1 layer
— PRACH/PUCCH/PUSCH
— Up to 4 layer codebook-based beamforming for DL SU-MIMO
— DL codebook-based beamforming
— CSI-RS configurations and CSI reports
MOM-configurable
sector shape and
digital tilt
HIGHRISE V
H

SystemConfigurations
— Operators can configure systems with MOM attributes for the following
deployment scenarios:
— Macro site (large horizontal angle, relatively smaller vertical angle)
— Hot spot (large horizontal angle, large vertical angle)
— High-rise (relatively smaller horizontal angle, large vertical angle)
Deployment
scenario
Macro site Hot spot High Rise
Horizontal HPBW 65o 65o 20o
Vertical HPBW 8o 30o 30o

Energy Performance
Feature

MicroSleepTx
— Micro Sleep Tx decreases energy consumption in the RU by automatically turning off the PA when
there is nothing to transmit on the downlink.
— When no data is scheduled in the cell, it is possible to turn off the PA without degrading the
performance. Better energy savings potential in NR because of less continuous system information
transmission compared to LTE.
— Micro Sleep Tx is basic feature and always enabled.

Throughput

PeakL2Throughput(Mbps)
Downlink,Single-layer
› For multiple layers, the single-layer peak throughput is scaled by the number of layers.
› Supported configuration in 2018Q4:
› TDD pattern: 3DL+1UL slots
› 20/100MHz BW, 1+1 DMRS and up to 2 layers  725 Mbps *
› Up to 4 layers in demo/limited field trial  1.4 Gbps *
• Note: Throughput provided by NR leg. The throughput provided by LTE leg may be aggregated with NR leg through LTE-NR Dual connectivity.
LTE CA is supported pending UE capability.
0.00
50.00
100.00
150.00
200.00
250.00
300.00
350.00
400.00
450.00
1 DMRS 1+1 DMRS 1 DMRS 1+1 DMRS
64QAM 256QAM
Peak L2 Throughput (Mbps)
Downlink, Single-layer
20 40 60 80 100

AggregatedLTE+NRPeakThroughput(Mbps)
Downlink
0.00
500.00
1000.00
1500.00
2000.00
2500.00
3000.00
NR 2 layers NR 4 layers NR 2 layers NR 4 layers
64QAM 256QAM
Aggregated LTE + NR Peak Throughput (Mbps)
(Downlink)
20 40 60 80 100
› LTE FDD DL peak throughput is based on 16 DL MIMO layers ( with DL 4/5CC CA).
– LTE CA is pending on UE capabilities
› The EN-DC efficiency factor is assumed to be 0.8 ( This factor may vary in different load and RF condition).
› NR Throughput is based on “3DL+1UL” TDD Pattern supported in 2018 Q4 :
› 20/100MHz BW, 1+1 DMRS and up to 2 layers  725 Mbps *
› Up to 4 layers in demo/limited field trial  1.4 Gbps *

PeakNRThroughput(Mbps)
Uplink,Single-layer
0
20
40
60
80
100
120
140
20 40 60 80 100
Peak L2 Throughput (Mbps)
Uplink, Single-layer
64QAM 1 DMRS 64QAM 1+1 DMRS
› Supported configuration in 2018Q4:
› TDD pattern: 3DL+1UL slots
› 20/100MHz BW, 1+1 DMRS and uplink 1 layer
• Note: Throughput provided by NR leg.

— MAC – MediumAccess Control
— MCS – ModulationCoding Scheme
— MIB – MasterInformation Block
— NR – New Radio
— NSA – Non-Standalone
— RAR - RandomAccess Response
— RBG - Resource Block Group
— REG – Resource-elementGroup
— RI – RankIndicator
— RLC – RadioLink Control
— RS – Reference Signal
— SCS – Subcarrier Spacing
— SPS - Semi-persistentScheduling
— SR – Scheduling Request
— SRS – Sounding Reference Signal
— SSS - Secondary SynchronizationSignal
— SU-MIMO - Single-userMultiple Input Multiple Output
— TB – TransportBlock
— TPC - TransmitPower Control
— TRS - TrackingReference Signal
— UCI - Uplinkcontrolinformation
— USS - UE-specificSearchSpace
— BWP – Bandwidth Part
— CBG – Code Block Group
— CCE – Control ChannelElement
— CQI – ChannelQuality Indicator
— CORESET – Control Resource Set
— CP – Cyclic Prefix
— CSI - Channelstate information
— CSI-IM CSI-Interference Management
— CSS – Common Search Space
— DCI - Downlink control information
— DMRS – Demodulation Reference Signal
— FR1 – Frequency Range 1
— PBCH - PhysicalBroadcast Channel
— PDCCH - PhysicalDownlink Control Channel
— PDCP - Packet Data Convergence Protocol
— PDSCH - Physical Downlink Shared Channel
— PHR – Power Headroom Report
— PRACH - PhysicalRandom Access Channel
— PRB – PhysicalResource Block
— PRG - Precoding Resource Block Group
— PSS- Primary Synchronization Signal
— PUCCH - PhysicalUplink Control Channel
— PUSCH - Physical Uplink Chared channel
Abbreviations

Deep Dive 5G NR-RAN Release 2018 Q4 Swisscom - L1 & RM.pdf

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