5g Ran2.0 Channel Management_1.1
Short Description
5g Ran2.0 Channel Management_1.1...
Description
5G RAN2.0 Channel Management
www.huawei.com
Copyright © 2018 Huawei Technologies Technologies Co., Ltd. All rights reserved.
Objectives
After completing this course, you will be able able to:
Describe PDCCH resource management.
Describe PUCCH resource management.
Describe SRS resource management.
Describe basic functions of uplink timing.
Describe basic functions of random access.
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Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 3
Overview
Channel type
Logical channels connect the MAC layer and the RLC layer. Logical channels are classified into control channels and traffic channels based on the type of transmitted data.
Control channels include:
BCCH
PCCH
CCCH
DCCH
Traffic channels include:
DTCH
Page 4
Overview
Channel type
Transport channels connect the MAC layer and the physical layer to transmit service data from the MAC layer and higher layers. Transport channels are classified based on the type of transmitted data and the method of data transmission over
the air interface.
Downlink transport channels include:
BCH
DL-SCH
PCH
Uplink transport channels include:
UL-SCH
RACH Page 5
Overview
Channel type
Physical channels host functions such as coding, modulation, multiantenna processing, and mapping from signals to appropriate physical time-frequency resources. Based on the mapping, an upper-layer transport channel can provide services to one or more physical channels at the physical layer.
Downlink physical channels include:
PBCH
PDCCH
PDSCH
Uplink physical channels include:
PUCCH
PUSCH
PRACH Page 6
Overview
Channel mapping (uplink)
CCCH
DCCH
DTCH Uplink logical channel
RLC Uplink transport channel MAC
UL-SCH
RACH Uplink physical channel
PHY
PUSCH
PRACH
PUCCH
Page 7
Overview
Channel Channel mapping mapping (downlink (downlink)) BCCH
PCCH
CCCH
DCCH
DTCH Downlink logical channel
RLC
MAC
Downlink transport channel BCH
PCH
DL-SCH Downlink physical channel
PHY
PBCH
PDSCH
PDCCH
Page 8
Overview
Uplink/downlink physical channel resource mapping
Example: C band 30 kHz subcarrier
Page 9
Overview
Channel management involves uplink and downlink channel resource management (such as PDCCH, PUCCH, and SRS), uplink timing, and random access.
Channel Channel managemen managementt delivers delivers the following following benefits: benefits:
Allocating signaling resources to minimize signaling overheads while ensuring signaling demodulation performance to maximize data throughput.
Ensuring the access success rate and timing precision, and reducing delay.
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Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 11
PDCCH The PDCCH carries downlink control information (DCI). The DCI includes: •
Downlink grants
Including information such as PDSCH resource indication, modulation and coding schemes (MCSs), and HARQ processes. DCI formats such as format 1_0 and format 1_1 are supported. •
Uplink grants
Including information such as PUSCH resource indication and MCSs. DCI formats such as f ormat 0_0 and format 0_1 are supported. •
Power control commands
PUSCH power control commands for a set of UEs as a complement to the PUSCH and physical uplink control channel (PUCCH) power control commands in uplink grants.
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PDCCH According to New Radio (NR) specifications, the PDCCH occupies the first one to three symbols of a slot in the time domain and supports full bandwidths in the frequency domain. The figure on the right shows the PDCCH. Each grid represents an RE.
A control channel element (CCE) is the smallest resource unit for
PDCCH symbol RE
PDCCH transmissions. One CCE contains six resource element groups (REGs) and one REG corresponds to one resour ce block (RB) in the frequency domain. 1, 2, 4, 8, or 16 CCEs can be aggregated on a PDCCH according
REG
to NR specifications. The aggregation level indicates the number of CCEs a PDCCH occupies. For example, aggregation level 1
CCE
indicates that the PDCCH occupies one CCE and aggregation level 2 indicates that the PDCCH occupies two CCEs.
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DMRS
PDCCH Resource Management
PDCCH resource management involves:
PDCCH time-frequency resources
PDCCH aggregation level selection
PDCCH resource allocation
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PDCCH Time-Frequency Resources 5G RAN2.0: •
PDCCH position in the time domain: The PDCCH is mapped to the downlink slot and self-contained slot (transmitting uplink and downlink symbols). By default, the PDCCH starts from the first symbol. The current version supports one or two symbols, which can be specified by the NRDUCellPdcch. OccupiedSymbolNum parameter.
•
PDCCH position in the frequency domain: mapped to full bandwidths in granularity of CCEs by default. When the PDSCH rate-match function is effective, the PDCCH and PDSCH share symbols and the frequencydomain range occupied by each PDCCH symbol for a cell can be configured using the NRDUCellPdcch.OccupiedRbNum parameter.
•
The NRDUCellPdcch.UlMaxCcePct parameter specifies the percentage of available uplink CCEs to available downlink CCEs for slots where DCI is simultaneously transmitted in the uplink and downlink.
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PDCCH Aggregation Level Selection Start
1. The gNodeB calculates the CQI using the CQI adjustment algorithm. DCI
CQI SINRrs
2. The gNodeB calculates the downlink RS SINR based on the CQI.
4. The gNodeB calculates the demodulation threshold for different bit rates and aggregation levels based on the DCI format.
3. The gNodeB calculates the PDCCH SINR based on the downlink RS SINR.
SINRpdcch 5. The gNodeB compares the PDCCH SINR and the demodulation threshold for each aggregation level, and selects a proper PDCCH aggregation level.
End
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SINR1, SINR2, SINR4, SINR8, SINR16
PDCCH Aggregation Level Selection
The gNodeB modifies the PDCCH aggregation level based on CQI-indicated channel quality and then the PDCCH BLER.
If the PDCCH BLER is greater than the target BLER, the gNodeB increases the aggregation level to improve PDCCH coverage performance.
If the PDCCH BLER is less than the target BLER, the gNodeB lowers the aggregation level to reduce the PDCCH resource usage.
The target PDCCH BLER can be adjusted using the NRDUCellRsvdParam.RsvdU8Param15 parameter.
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PDCCH Resource Allocation
Common search space and UE-specific search space are involved on a PDCCH. Common search space corresponds to common message scheduling. UE-specific search space corresponds to UE-specific data scheduling.
The number of blind detections in the common search space is predefined by the protocol. The UE-specific search space is configured through signaling messages. The number of blind detections cannot exceed the upper limit defined in the protocol.
The gNodeB allocates CCE resources to UEs. The start resource position is determined based on the protocol-defined candidate position (such as UeId, slotNumber, PDCCH blind detection range), aggregation level, and number of blind detections.
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PDCCH Parameters
NRDUCellPdcch.UlMaxCcePct
Parameter name: Uplink Maximum CCE Percentage
Recommended value: 50%. Configure this parameter as required.
NRDUCellPdcch.OccupiedSymbolNum
Parameter name: Occupied Symbol Number
Recommended value: 1SYM. Configure this parameter based on the c ell load.
NRDUCellPdcch.OccupiedRbum
Parameter name: Occupied RB Number
Recommended value: 0 (indicating full bandwidths). Configure this parameter depending on application scenarios.
NRDUCellRsvdParam.RsvdU8Param15
Parameter name: Reserved U8 Parameter 15
Recommended value: 3 (the actual value is 0.015 and the configuration step is 0.005). Configure this parameter depending on application scenarios. Page 19
Question
Which of the following are PDCCH aggregation levels?
A: 2 B: 4 C: 6 D: 8
How many RBs does one CCE correspond to?
A: 3 B: 6 C: 12 Page 20
Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 21
PUCCH Information Type PUCCH Structure
Short structure
Long structure
Application Scenario
Format
Number of Symbols
Information
Modulation Scheme
Number of Bits per Subframe
0
1 –2
SR+/HARQ
QPSK/BPSK
1 to 2 bits
2
1 –2
HARQ+CSI+/SR
QPSK
Scheduling determines bits to be transmitted.
1
4 –14
SR+/HARQ
QPSK/BPSK
1 to 2 bits
3, 4
4 –14
HARQ+CSI+/SR
QPSK/π/2BPSK
Scheduling determines bits to be transmitted.
Short delay
Deep coverage
In 19A: Short structure: one symbol in format 0 and format 2 Long structure: 10/11/12/13/14 symbols in format 1 and format 3. The number of symbols in a long PUCCH depends on the number of remaining symbols in the upli nk timeslot after symbols for the short PUCCH and SRS symbols are allocated.
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PUCCH Resource Allocation
The gNodeB allocates resource sets (a maximum of four sets) to a UE through the higher-layer RRC IE. Each resource set includes eight PUCCH resources,
with each including configuration information such as the time-frequency position, index ID, start symbol, and symbol quantity.
In format 2 and format 3, each resource includes the number of RBs.
In format 1 and format 4, each resource includes code division multiplexing information.
The gNodeB allocates one set of idle PUCCH resources to a UE to send HARQ based on PDSCH scheduling, and sends DCI to inform the UE of the resource set index ID.
The gNodeB allocates fixed time-frequency resources to the UE for sending SRs.
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HARQ-ACK
A UE uses a HARQ-ACK to report whether PDSCH decoding succeeds.
If the UE successfully receives data from the gNodeB, it sends an ACK.
If the UE fails to receive data from the gNodeB, it sends a NACK.
PUCCH RBs need to be allocated to UEs for sending HARQ-ACKs.
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Static SRI Reservation
A UE uses an SRI to request an uplink bandwidth from the gNodeB.
The gNodeB uses static PUCCH resource allocation and reserves SRI resources in the PUCCH resources.
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CSI (CQI/PMI/RI)
CSI (CQI/PMI/RI) indicates downlink channel quality. The gNodeB controls CSI reporting of UEs. UEs report CSI to the gNodeB over the PUSCH in event-triggered mode.
CQI: whether CQI is included in CSI is determined by the
gNodeB.
PMI: whether PMI is included in CSI is determined by the gNodeB.
RI: whether RI is included in CSI is determined by the gNodeB.
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PUCCH Parameters
NRDUCellPucch.StructureType
Recommended value: LONG_STRUCTURE. Configure this parameter depending on application scenarios.
NRDUCellPucch.Format3RbNum
Parameter name: Format3 RB Number
Recommended value: 4RB. Configure this parameter depending on application scenarios.
NRDUCellPucch.Format1RbNum
Parameter name: Format1 RB Number
Recommended value: 4RB. Configure this parameter depending on application scenarios.
NRDUCellPucch.SrPeriod
Parameter name: SR Period
Recommended value: SLOT40. Configure this parameter depending on application scenarios.
NRDUCellPucch.HfRxBeamNum
Parameter name: Structure Type
Parameter name: HF Receive Beam Number Recommended value: BEAM2. Configure this parameter depending on application scenarios. The value of this parameter can be automatically configured in the future.
NRDUCellPucch.ShortPucchSymbolNum
Parameter name: Short P UCCH Symbol Number
Recommended value: SYMBOL1. Configure this parameter depending on application scenarios.
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Question
Is the following statement true or false: QPSK is applied on the PUCCH in an NR system?
Answer: true
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Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 29
SRS –Overview
SRS refers to uplink sounding signal. In this version, a UE sends an SRS within the activated bandwidth part (BWP). The gNodeB receives and processes the SRS, and measures the signal to interference plus noise ratio (SINR), reference signal received power (RSRP), and PMI of the SRS. Then, the gNodeB determines the functions for which the information is used based on the value of usage in SRS-Config contained in the SRS (usage can only be set to codebook or antennaSwitching in the current version). Value of usage
Function
Description
codebook
Uplink SU-MIMO/MU-MIMO
UEs weight data to be transmitted based on the PMI.
The gNodeB performs uplink link adaptive (LA) based on the SRS and sends the result to the UE to instruct the UE to send data.
Uplink beam management
This function is used to select optimal receive beams on the gNodeB.
Uplink timing antennaSwitching Downlink SU-MIMO/MU-
MIMO
The gNodeB weights data to be transmitted based on the SRS weight.
The gNodeB performs downlink LA based on the SRS and uses the LA result to send data.
Downlink beam management This function is used to select optimal transmit beams on the gNodeB for serving downlink channels.
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SRS Type SRSs are classified into periodic, aperiodic, and semi-persistent SRSs.
Periodic SRS
After receiving periodic SRS resource configuration data, a UE periodically sends SRSs.
Semi-persistent SRS
After receiving semi-persistent SRS resource configuration data, a UE periodically sends SRSs only when the MAC CE is activated.
Aperiodic SRS
After receiving aperiodic SRS resource configuration data, a UE sends SRSs according to the DCI. In this version, only periodic and aperiodic SRSs are supported.
In low-frequency TDD, periodic SRSs are sent.
In high-frequency TDD, aperiodic SRSs are sent.
In low-frequency FDD, aperiodic SRSs are sent.
Cell-specific SRS Slot Configuration
• •
•
•
•
A cell-specific SRS slot includes time-domain resources used by all UEs in a cell to transmit SRSs. In an NR system, the gNodeB obtains the number and positions of slots for SRSs in a radio frame according to the timeslot allocation, and the number and positions of SRS symbols available in the SRS slots. FDD When uplink spectrum sharing is disabled, slots 0 and 5 i n a radio frame can be configured for sending SRSs, which are transmitted over symbol 13 of these slots. When uplink spectrum sharing is enabled, slots in a radio frame for sending SRSs are automatically adjusted based on the number of UEs. SRSs are transmitted over symbol 13 of these slots. TDD 4:1 low frequency: Self-contained slots in a radio frame can be configured for sending SRSs. Self-contained slots are numbered 3, 8, 13, and 18. SRSs are transmitted over symbols 12 and 13 of these slots. 4:1 high frequency: Uplink only slots in a radio frame can be configured for sending SRSs. Uplink only slots are numbered 14 and 54. SRSs are transmitted over symbols 10, 11, 12, and 13 of these slots. 8:2 low frequency: Self-contained slots in a radio frame can be configured for sending SRSs. Self-contained slots are numbered 7 and 17. SRSs are transmitted over symbols 10, 11, 12, and 13 of these slots.
UE-specific SRS Bandwidth
The UE-specific SRS bandwidth configurations include SRS bandwidths that can
be allocated to UEs in a cell. 3GPP specifications define a maximum of four SRS bandwidths. The gNodeB selects a bandwidth configuration from the four configurations. In this version, BW0 (depth = 1) or BW1 (depth = 2) is configured for aperiodic SRSs. Aperiodic SRSs use BW2 (depth = 3) by default.
The following is an SRS bandwidth tree, indicating that the SRS bandwidths for UEs in a cell can be 32 RBs, 16 RBs, 8 RBs, or 4 RBs.
The bandwidth tree depends on the BWP bandwidth.
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UE-specific SRS Bandwidth Configuration Bandwidth
CSRS
configuration of
NRLoCellRsvdParam.Rs When this parameter is set to 255, C SRS is vdU8Param58
periodic SRSs
the one corresponding to the maximum bandwidth of the UE-specific periodic SRS (bandwidth for BSRS = 0) that is less than and most close to the UE's BWP.
BSRS
NRLoCellRsvdParam.Rsv When this parameter is set to 255, BSRS is 2. dU8Param59
Bandwidth
CSRS
-
CSRS is the one corresponding to the maximum
configuration of
bandwidth of the UE-specific periodic SRS
aperiodic SRSs
(bandwidth for BSRS = 0) that is less than and most close to the UE's BWP. BSRS
-
FDD low frequency bands: BSRS = 0 TDD high frequency bands: BSRS is determined by the value of usage in the SRS-Config as follows: If the value of usage is codebook, BSRS is 2. If the value of usage is antennaSwitching, BSRS is 0.
UE-specific SRS Parameter Delivery
UE-specific SRS parameters are carried in RRC signaling messages. Parameters related
to both periodic SRSs and aperiodic SRSs are contained in the same set of RRC signaling. Periodic SRSs can be directly sent whereas aperiodic SRSs are triggered by DCI.
In the NR system, multiple SRS resource sets can be configured for a UE and an SRS resource set can contain multiple SRS resources. Resource configuration data of both periodic SRSs and aperiodic SRSs is sent to UEs through the same set of RRC signaling messages. Resources are configured in different sets with the resource type indicating periodic or aperiodic.
Each SRS is configured with "usage", whose value range is {codebook,noncodebook,BeamManagement,antennaSwitching}. In this version, only codebook (for uplink measurement) and antennaSwitching (SRS antenna polling for downlink measurement) are supported.
SRS Parameters
Param1WithParamId97 (SRS period)
Parameter name: Parameter 1 with ParamId=97
Value range: SL5, SL10, SL20, SL40, SL80, SL160, SL320, SL640, SL1280
Default value: SL80
RsvdU8Param58, RsvdU8Param59 (UE-specific periodic SRS bandwidth)
Parameter name: Reserved U8 Parameter 58, Reserved U8 Parameter 59
Default value: 255(Adaptive) = Bw2 Parameter
Meaning
Value Range
Default Value
RsvdU8Param58
CSRS
0~63, 255
255(Adaptive)
RsvdU8Param59
BSRS
0~3, 255
255(Adaptive)
Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 37
Uplink Timing –Basic Principles
Ensure that uplink data sent by UEs that are located from the gNodeB at different
distances reaches the gNodeB at the same time.
The gNodeB delivers a TA adjustment command through the random access response (RAR) or MAC Control Element (CE).
The UE adjusts the time advance of uplink transmission relative to downlink transmission based on the indicated TA adjustment amount.
If a UE receives the TA adjustment command in slot n, it applies the TA adjustment amount in slot
n
plus 6.
If the gNodeB does not receive the TA value reported by Layer 1 within the TA delivery period, the gNodeB instructs the UE to send an SRS to ensure that the TA is obtained.
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Uplink Timing –Process No difference between high and low frequencies
Page 39
Uplink Timing –TA Timer Configuration SCS = 15 kHz UE Moving Speed km/h
Standard TA Timer/ms
Extended TA Timer/ms
Final TA Timer/SF
Final TA Timer/ms
30
9375
14062.5
10240
10240
60
4688
7032
5120
5120
120
2344
3516
2560
2560
180
1563
2344.5
1920
1920
300
938
1407
1280
1280
600
469
703.5
750
750
650
433
649.5
500
500
1 subframe = 1 ms
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Uplink Timing –TA Timer Configuration SCS = 30 kHz UE Moving Speed
Standard TA
Extended TA
Final TA
km/h
Timer/ms
Timer/ms
Timer/SF
30
4687.50
7031.25
5120
60
2343.75
3515.63
2560
120
1171.88
1757.81
1280
SCS = 60 kHz UE Moving Speed km/h
Standard TA Timer/ms
Extended TA Timer/ms
Final TA Timer/SF
30
2343.75
3515.63
2560
60
1171.88
1757.81
1280
120
585.94
878.91
750
Page 41
Uplink Timing –TA Timer Configuration SCS = 120 kHz UE Moving Speed km/h
Standard TA Timer/ms
Extended TA
Final TA Timer
Timer/ms
Value/SF
30
1171.88
1757.80
1280
60
585.94
878.91
750
120
292.97
439.45
500
Page 42
Uplink Timing –Related Parameters
NRLoCellUlTaConfig
Parameter name: Uplink Time Alignment Timer
(UlTimeAlignmentTimer)
Recommended value:
10240SF(10240 Subframes) if the UE's mobility speed is 30 km /h
5120SF(5120 Subframes) if the UE's mobility speed is 60 km/h
2560SF(2560 Subframes) if the UE's mobility speed is 120 k m/h
1920SF(1920 Subframes) if the UE's mobility speed is 180 k m/h
1280SF(1280 Subframes) if the UE's mobility speed is 300 k m/h
750SF(750 Subframes) if the UE's mobility speed is 600 km/h
500SF(500 Subframes) if the UE's mobility speed is 650 km/h Page 43
Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 44
Random Access Functions
During random access, the UE attempting to access the network sends an access request to the gNodeB, and the gNodeB responds to the request, allocating resources to the UE.
Random access provides the following benefits (5G RAN2.0 does not support beam recovery.): 1. Setting up uplink synchronization with the gNodeB
2. Requesting resources 3. Requesting SIs 4. Beam recovery
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Random Access Scenarios and Types
The following are random access scenarios and types. In 5G RAN2.0, case 8 is supported.
Index
Random Access Scenario
Random Access Type
Case 1 Initial RRC connection setup Contention-based random access Case 2
RRC connection reestablishment
Contention-based random access
Case 3 Handover
Non-contention-based random access is the first choice. Contentionbased random access is used when dedicated preambles are used up.
Case 4 Downlink data arrival
Non-contention-based random access is the first choice. Contentionbased random access is used when dedicated preambles are used up.
Case 5 Uplink data arrival
Contention-based random access
State transition from Case 6 RRC_INACTIVE to RRC_CONNECTED
A UE initiates contention-based RA to transit to a different state. Noncontention-based RA is the first choice if the gNodeB initiates state transition. Contention-based RA is used when dedicated preambles are used up.
Case 7 Requests for specific SIs
Non-contention-based random access
Case 8
NR cell addition in NSA networking
Case 9 Beam recovery
Non-contention-based random access Non-contention-based random access
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Contention-based Random Access Contention-based random access process
Contention resolution is completed through Msg3 and Msg4.
1. Msg3 includes the UE Contention Resolution Identity (CRI), which is the TMSI of the UE or a 48-bit random number. The CRI varies with UEs. 2. After demodulating Msg3, the gNodeB obtains the CRI and includes the CRI in Msg4 sent to the UE. The UE checks whether the CRI in Msg4 is consistent with that in Msg3 to determine whether the contention succeeds.
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Non-contention-based Random Access Non-contention-based random access process
Unlike contention-based random access, non-contention-based random access involves preamble assignment (step 0, this is because
dedicated preambles are required), and does not involve contention resolution (therefore Msg3 and Msg4 are not defined).
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PRACH Position in the Time Domain – 1/2 •
When a UE initiates random access by sending signals on the PRACH, the specific time-domain position is determined by the frame number, subframe number, slot number, and occasion number. See the following figure. Frame for PRACH
PRACH period …
…
…
…
Subframe for PRACH
0
1
2
3
PRACH occasion
PRACH slot
5
6
7
8
PRACH Position in the Time Domain – 2/2 •
The time-domain position of a PRACH is determined by the PRACH Configuration Index. The following are examples. Table1. PRACH Configuration Index (sub-6 GHz)
NSFN mod x=y PRACH Configurati on Index
Preambl e Format
245 255
x
y
C2
1
0
C2
4
Subfram Start e Symbo Number l
9
8
Number of PRACH Slots Within a Subframe
Number of Time-Domain PRACH Occasions Within a PRACH Slot
PRACH Duratio n
1
1
6
1
6
Number of PRACH Slots Within a 60 kHz Slot
Number of Time-Domain PRACH Occasions Within a PRACH Slot
PRACH Duratio n
1 9 8 1 Table2. PRACH Configuration Index (above-6 GHz)
NSFN mod x=y PRACH Configurati on Index
Preambl e Format
228 229
Start Slot Symbo Number l
x
y
C2
1
0
9,19,29,39
8
1
1
6
C2
1
0
4,14,24,34
8
1
1
6
Note: The start symbol and PRACH duration are determined according to the PRACH, which must be considered when the PRACH SCS is different from data SCS.
PRACH Position in the Frequency Domain
The following figure shows the frequency-domain position of a PRACH. The following table lists the number of occupied PRBs in the frequency domain.
System
Initial BWP
bandwidth PRACH PUCCH
Sequenc e Length
PRACH SCS
PUSCH SCS
PRACH PRB (from the Perspective of PUSCH)
839
1.25
15
6
839
1.25
30
3
839
1.25
60
2
839
5
15
24
839
5
30
12
839
5
60
6
139
15
15
12
139
15
30
6
139
15
60
3
139
30
15
24
139
30
30
12
139
30
60
6
139
60
60
12
139
60
120
6
139
120
60
24
139
120
120
12
The PRACH is located at the lowest frequency of the initial BWP and is staggered from the common PUCCH.
Preamble Structure in the Time Domain CP
Sequence
TCP
TSEQ
Guard interval
Preamble
UE A
UE B
gNodeB UE A
UE B Delay for UE B resulting from the distance
CP
Sequence
CP
Sequence
gNodeB access window
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Preamble Format
14 preamble formats are available for the NR system, including 10 short s equences and four long sequences. For short sequences, 15, 30, 60, or 120 kHz SCS is supported. The sub-6 GHz band supports short sequences and long sequences. The mmWave supports only short sequences. 5G RAN2.0 supports format 0 and C2. Format
Sequence L ength
Subcarrier S pacing
Time Domain Length
Occupied Bandwidth
Maximum Cell Radius
0
839 (long sequence)
1.25 kHz
1.0 ms
1.08 MHz
14.5 km
1
839
1.25 kHz
3.0 ms
1.08 MHz
100.1 km
2
839
1.25 kHz
3.5 ms
1.08 MHz
21.9 km
3
839
5.0 kHz
1.0 ms
4.32 MHz
14.5 km
A1
139 (short sequence) 15·2μ (μ = 0/1/2/3)
0.14/2μ ms
2.16·2μ MHz
0.937/2μ km
A2
139
15·2μ
0.29/2μ ms
2.16·2μ MHz
2.109/2μ km
A3
139
15·2μ
0.43/2μ ms
2.16·2μ MHz
3.515/2μ km
B1
139
15·2μ
0.14/2μ ms
2.16·2μ MHz
0.585/2μ km
B2
139
15·2μ
0.29/2μ ms
2.16·2μ MHz
1.054/2μ km
B3
139
15·2μ
0.43/2μ ms
2.16·2μ MHz
1.757/2μ km
B4
139
15·2μ
0.86/2μ ms
2.16·2μ MHz
3.867/2μ km
C0
139
15·2μ
0.14/2μ ms
2.16·2μ MHz
5.351/2μ km
C2
139
15·2μ
0.43/2μ ms
2.16·2μ MHz
9.297/2μ km
Page 53
Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 54
PDCCH –Deployment
Run the MOD NRDUCELLPDCCH command to configure the maximum proportion of uplink CCEs (default value: 50%).
Run the MOD NRDUCELLPDCCH command to set the number of occupied symbols. The default value is 1SYM.
Page 55
PUCCH –Deployment
Run the MML command MOD NRLOCELLPUCCH to configure the number of RBs used for format 3 and structure type.
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SRS –Deployment
Run the MML command MOD NRLOCELLSRS to set the SRS switch, UE-specific SRS period, and SNR threshold for triggering aperiodic SRSs.
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TA –Deployment
Run the MML command MOD NRLOCELLULTACONFIG to configure the TA timer length (default value: 10240SF).
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Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 59
PDCCH –Counters
CCE usage-related counters
Counter
Description
L.ChMeas.CCE.UL Used
Number of PDCCH CCEs used for uplink DCI
L.ChMeas.CCE.DLUsed
Number of PDCCH CCEs used for downlink DCI
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PRACH –Counters Counter
Description
N.RA.Contention.Att
Number of random preamble receptions
N.RA.Contention.Att.Max
Maximum number of random preamble receptions
N.RA.Contention.Resolution.Succ
Number of successful contention resolutions
N.RA.Dedicated.Att
Number of dedicated preamble receptions
N.RA.Dedicated.Msg3
Number of Msg3 receptions during non-contention based random access
Page 61
Contents 1. Overview 2. PDCCH Resource Management 3. PUCCH Resource Management 4. SRS Resource Management 5. Uplink Timing 6. Random Access 7. Deployment 8. Counters 9. Acronyms and Abbreviations Page 62
Acronyms and Abbreviations
PDCCH: Physical Downlink Control Channel
DCI: Downlink Control Information
HARQ: Hybrid Automatic Repeat Request
CCE: Control-Channel Element
PUCCH: Physical Uplink Control Channel
SRS: Sounding Reference Signal
TA: Time Alignment
BWP: Bandwidth Part Page 63
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