[OpenAirInterface实战-4] ：OAI支持的4G LTE功能集

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本文网址：https://blog.csdn.net/HiWangWenBing/article/details/120524557

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目录

前言：

第1章 LTE协议栈

第2章 OpenAirInterface 4G LTE eNB Feature Set

2.1 eNB PHY Layer

3.2 Performances

3.3 Number of supported UEs

3.4 eNB MAC Layer

3.4 eNB RLC Layer

3.5 eNB PDCP Layer

3.6 eNB RRC Layer

3.7 eNB X2AP

3.8 eNB/MCE M2AP 

3.9 MCE/MME M3AP （与MME的接口）

第4章 OpenAirInterface 4G LTE UE Feature Set

4.1 LTE UE PHY Layer

4.2 LTE UE MAC Layer

4.3 LTE UE RLC Layer

4.4 LTE UE PDCP Layer

4.5 LTE UE RRC Layer

4.5 LTE UE NAS Layer（与MME接口）

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前言：

参考： doc/FEATURE_SET.md · develop · oai / openairinterface5G · GitLab

第1章 LTE协议栈

第2章 OpenAirInterface 4G LTE eNB Feature Set

2.1 eNB PHY Layer

The Physical layer implements 3GPP 36.211, 36.212, 36.213 and provides the following features:

• LTE release 8.6 compliant, and implements a subset of release 10
• FDD and TDD configurations: 1 (experimental) and 3
• Bandwidth: 5, 10, and 20 MHz
• Transmission modes: 1, 2 (stable), 3, 4, 5, 6, 7 (experimental)
• Max number of antennas: 2 （不支持4T4R）
• CQI/PMI reporting: aperiodic, feedback mode 3 - 0 and 3 - 1
• PRACH preamble format 0 
• Downlink (DL) channels are supported: PSS, SSS, PBCH, PCFICH, PHICH, PDCCH, PDSCH, PMCH, MPDCCH
• Uplink (UL) channels are supported: PRACH, PUSCH, PUCCH (format 1/1a/1b), SRS, DRS
• HARQ support (UL and DL)
• Highly optimized base band processing (including turbo decoder)
• Multi-RRU support: over the air synchro b/ multi RRU in TDD mode
• Support for CE-modeA for LTE-M. Limited support for repeatition, single-LTE-M connection, legacy-LTE UE attach is disabled.

3.2 Performances

Transmission Mode, Bandwidth	Expected Throughput	Measured Throughput	Measurement Conditions
FDD DL: 5 MHz, 25 PRBS/ MCS 28	16 - 17 Mbit/s	TM1: 17.0 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
FDD DL: 10 MHz, 50 PRBS/ MCS 28	34 - 35 Mbit/s	TM1: 34.0 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
FDD DL: 20 MHz, 100 PRBS/ MCS 28	70 Mbit/s	TM1: 69.9 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
FDD UL: 5 MHz, 25 PRBS/ MCS 20	9 Mbit/s	TM1: 8.28 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
FDD UL: 10 MHz, 50 PRBS/ MCS 20	17 Mbit/s	TM1: 18.3 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
FDD UL: 20 MHz, 100 PRBS/ MCS 20	35 Mbit/s	TM1: 18.6 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
TDD DL: 5 MHz, 25 PRBS/ MCS XX	6.5 Mbit/s	TM1: 6.71 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
TDD DL: 10 MHz, 50 PRBS/ MCS XX	13.5 Mbit/s	TM1: 13.6 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
TDD DL: 20 MHz, 100 PRBS/ MCS XX	28.0 Mbit/s	TM1: 27.2 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
TDD UL: 5 MHz, 25 PRBS/ MCS XX	2.0 Mbit/s	TM1: 3.31 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
TDD UL: 10 MHz, 50 PRBS/ MCS XX	2.0 Mbit/s	TM1: 7.25 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)
TDD UL: 20 MHz, 100 PRBS/ MCS XX	3.0 Mbit/s	TM1: 4.21 Mbits/s	COTS-UE Cat 4 (150/50 Mbps)

3.3 Number of supported UEs

• 16 by default (16个用户)
• up to 256 when compiling with dedicated compile flag （需要更多的计算资源）
• was tested with 40 COTS-UE （40个用户是经过测试的）

3.4 eNB MAC Layer

The MAC layer implements a subset of the 3GPP 36.321 release v8.6 in support of BCH, DLSCH, RACH, and ULSCH channels.

• RRC interface for CCCH, DCCH, and DTCH
• Proportional fair scheduler (round robin scheduler soon), with the following improvements:
  • Up to 30 users tested in the L2 simulator, CCE allocation in the preprocessor ; the scheduler was also simplified and made more modular
  • Adaptative UL-HARQ
  • Remove out-of-sync UEs
  • No use of the first_rb in the UL scheduler ; respects vrb_map_UL and vrb_map in the DL
• DCI generation
• HARQ Support
• RA procedures and RNTI management
• RLC interface (AM, UM)
• UL power control
• Link adaptation
• Connected DRX (CDRX) support for FDD LTE UE. Compatible with R13 from 3GPP. Support for Cat-M1 UE comming soon.

3.4 eNB RLC Layer

The RLC layer implements a full specification of the 3GPP 36.322 release v9.3.

• RLC TM (mainly used for BCCH and CCCH)
  • Neither segment nor concatenate RLC SDUs
  • Do not include a RLC header in the RLC PDU
  • Delivery of received RLC PDUs to upper layers
• RLC UM (mainly used for DTCH)
  • Segment or concatenate RLC SDUs according to the TB size selected by MAC
  • Include a RLC header in the RLC PDU
  • Duplication detection
  • PDU reordering and reassembly
• RLC AM, compatible with 9.3
  • Segmentation, re-segmentation, concatenation, and reassembly
  • Padding
  • Data transfer to the user
  • RLC PDU retransmission in support of error control and correction
  • Generation of data/control PDUs

3.5 eNB PDCP Layer

The current PDCP layer is header compliant with 3GPP 36.323 Rel 10.1.0 and implements the following functions:

• User and control data transfer
• Sequence number management
• RB association with PDCP entity
• PDCP entity association with one or two RLC entities
• Integrity check and encryption using the AES and Snow3G algorithms

3.6 eNB RRC Layer

The RRC layer is based on 3GPP 36.331 v15.6 and implements the following functions:

• System Information broadcast (SIB 1, 2, 3, and 13)
  • SIB1: Up to 6 PLMN IDs broadcast
• RRC connection establishment
• RRC connection reconfiguration (addition and removal of radio bearers, connection release)
• RRC connection release
• RRC connection re-establishment
• Inter-frequency measurement collection and reporting (experimental)
• eMBMS for multicast and broadcast (experimental)
• Handover (experimental)
• Paging (soon)
• RRC inactivity timer (release of UE after a period of data inactivity)

3.7 eNB X2AP

The X2AP layer is based on 3GPP 36.423 v14.6.0 and implements the following functions:

• X2 Setup Request
• X2 Setup Response
• X2 Setup Failure
• Handover Request
• Handover Request Acknowledge
• UE Context Release
• X2 timers (t_reloc_prep, tx2_reloc_overall)
• Handover Cancel
• X2-U interface implemented
• EN-DC is implemented
• X2AP : Handling of SgNB Addition Request / Addition Request Acknowledge / Reconfiguration Complete
• RRC : Handling of RRC Connection Reconfiguration with 5G cell info, configuration of 5G-NR measurements
• S1AP : Handling of E-RAB Modification Indication / Confirmation

3.8 eNB/MCE M2AP 

The M2AP layer is based on 3GPP 36.443 v14.0.1:

• M2 Setup Request
• M2 Setup Response
• M2 Setup Failure
• M2 Scheduling Information
• M2 Scheduling Information Response
• M2 Session Start Request
• M2 Session Start Response

3.9 MCE/MME M3AP （与MME的接口）

The M3AP layer is based on 3GPP 36.444 v14.0.1:

• M3 Setup Request
• M3 Setup Response
• M3 Setup Failure
• M3 Session Start Request
• M3 Session Start Response

备注：也就是说，可以支持与核心网MME的连接。

第4章 OpenAirInterface 4G LTE UE Feature Set

4.1 LTE UE PHY Layer

The Physical layer implements 3GPP 36.211, 36.212, 36.213 and provides the following features:

• LTE release 8.6 compliant, and implements a subset of release 10
• FDD and TDD configurations: 1 (experimental) and 3
• Bandwidth: 5, 10, and 20 MHz
• Transmission modes: 1, 2 (stable) =》 UE只支持mode1,2
• Max number of antennas: 2 =》 两天线
• CQI/PMI reporting: aperiodic, feedback mode 3 - 0 and 3 - 1
• PRACH preamble format 0  
• All downlink (DL) channels are supported: PSS, SSS, PBCH, PCFICH, PHICH, PDCCH, PDSCH, PMCH
• All uplink (UL) channels are supported: PRACH, PUSCH, PUCCH (format 1/1a/1b), SRS, DRS
• LTE MBMS-dedicated cell (feMBMS) procedures subset for LTE release 14 (experimental)
• LTE non-MBSFN subframe (feMBMS) Carrier Adquistion Subframe-CAS procedures (PSS/SSS/PBCH/PDSH) (experimental)
• LTE MBSFN MBSFN subframe channel (feMBMS): PMCH ([email protected]) (channel estimation for 25MHz bandwidth) (experimental)

4.2 LTE UE MAC Layer

The MAC layer implements a subset of the 3GPP 36.321 release v8.6 in support of BCH, DLSCH, RACH, and ULSCH channels.

• RRC interface for CCCH, DCCH, and DTCH
• HARQ Support
• RA procedures and RNTI management
• RLC interface (AM, UM)
• UL power control
• Link adaptation
• MBMS-dedicated cell (feMBMS) RRC interface for BCCH
• eMBMS and MBMS-dedicated cell (feMBMS) RRC interface for MCCH, MTCH

4.3 LTE UE RLC Layer

The RLC layer implements a full specification of the 3GPP 36.322 release v9.3.

4.4 LTE UE PDCP Layer

The current PDCP layer is header compliant with 3GPP 36.323 Rel 10.1.0.

4.5 LTE UE RRC Layer

The RRC layer is based on 3GPP 36.331 v14.3.0 and implements the following functions:

• System Information decoding
• RRC connection establishment
• MBMS-dedicated cell (feMBMS) SI-MBMS/SIB1-MBMS management

4.5 LTE UE NAS Layer（与MME接口）

The NAS layer is based on 3GPP 24.301 and implements the following functions:

• EMM attach/detach, authentication, tracking area update, and more
• ESM default/dedicated bearer, PDN connectivity, and more

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作者主页(文火冰糖的硅基工坊)：文火冰糖（王文兵）的博客_文火冰糖的硅基工坊_CSDN博客

本文网址：https://blog.csdn.net/HiWangWenBing/article/details/120524557