在5G(NR)网络中RLC层PDU是一个字符串；RLC层SDU是长度对齐的位字符串。三种模式的数据结构分别如下：
1.RLC层TM模式数据结构整理：kangguoying202006106
2.RLC层UM模式数据结构
2.1 UM PDU包括RLC SDU整理：kangguoying202006106
38.322-Figure 6.2.1.3-1: UMD PDU containing a complete RLC SDU
2.2UM PDU包括SN(6比特)
38.322-Figure 6.2.2.3-2: UMD PDU with 6 bit SN (No SO)
2.3 UM PDU包括SN(12比特)整理：kangguoying202006106
38.322-Figure 6.2.2.3-3: UMD PDU with 12 bit SN (No SO)
2.4 UM PDU包括SN(6比特)和SO整理：kangguoying202006106
整理：kangguoying202006106
38.322-Figure 6.2.2.3-4: UMD PDU with 6 bit SN and with SO
2.5 UM PDU包括SN(12比特)和SO整理：kangguoying202006106
38.322-Figure 6.2.2.3-5: UMD PDU with 12 bit SN and with SO
SI : SI stands for Segment Information. The meaning of each possible SI field value is defined in the table below
SI为分段信息，其定义见下表：整理：kangguoying202006106
38.322-Table 6.2.2.4-1: SI field interpretation
3.RLC层AM模式数据结构整理：kangguoying202006106
3.1 AM模式PDU包括SN(12比特)整理：kangguoying202006106
38.322-Figure 6.2.1.4-1: AMD PDU with 12 bit SN (No SO)
3.2 AM模式PDU包括SN(18比特)整理：kangguoying202006106
38.322-Figure 6.2.1.4-2: AMD PDU with 18 bit SN (No SO)
3.3 AM模式PDU包括SN(12比特)和SO整理：kangguoying202006106
38.322-Figure 6.2.1.4-3: AMD PDU with 12 bit SN with SO
3.4 AM模式PDU包括SN(18比特)和SO整理：kangguoying202006106
38.322-Figure 6.2.1.4-4: AMD PDU with 18 bit SN with SO
SO:代表分段偏移，其指示在原始RLC SDU中SDU的分段位置整理：kangguoying202006106
D/C：该字段指示RLC PDU是数据还是控制位；整理：kangguoying202006106
38.322-Table 6.2.2.6-1: D/C field interpretation
P：意为轮询，其指示是否需从对方回执RLC ACK或NACK；整理：kangguoying202006106
38.322-Table 6.2.2.7-1: P field interpretation
SI:意为为分段信息，其定义见下表：整理：kangguoying202006106
38.322-Table 6.2.2.4-1: SI field interpretation
4.RLC AM模式
4.1PDU状态带12比特的SN
38.322-Figure 6.2.2.5-1: STATUS PDU with 12 bit SN
4.2 PDU状态带18比特的SN
38.322-Figure 6.2.2.5-2: STATUS PDU with 18 bit SN
5.RRC消息中RLC字段定义和取值整理：kangguoying202006106
RLC-BearerConfig ::= SEQUENCE {
logicalChannelIdentity LogicalChannelIdentity,
servedRadioBearer CHOICE {整理：kangguoying202006106
srb-Identity SRB-Identity,
drb-Identity DRB-Identity整理：kangguoying202006106
} OPTIONAL, -- Cond LCH-SetupOnly 整理：kangguoying202006106
reestablishRLC ENUMERATED {true} OPTIONAL, -- Need R
rlc-Config 整理：kangguoying202006106 RLC-Config OPTIONAL, -- Cond LCH-Setup
mac-LogicalChannelConfig LogicalChannelConfig OPTIONAL, -- Cond LCH-Setup ... }
RLC-Config ::= CHOICE {整理：kangguoying202006106
am 整理：kangguoying202006106 SEQUENCE {
ul-AM-RLC UL-AM-RLC,
dl-AM-RLC DL-AM-RLC },
um-Bi-Directional SEQUENCE {
ul-UM-RLC UL-UM-RLC,
dl-UM-RLC DL-UM-RLC },
um-Uni-Directional-UL SEQUENCE {
ul-UM-RLC UL-UM-RLC },
um-Uni-Directional-DL SEQUENCE {
dl-UM-RLC DL-UM-RLC }, ...}
UL-AM-RLC ::= SEQUENCE {整理：kangguoying202006106
sn-FieldLength SN-FieldLengthAM OPTIONAL, -- Cond Reestab
t-PollRetransmit T-PollRetransmit,
pollPDU PollPDU,整理：kangguoying202006106
pollByte PollByte,整理：kangguoying202006106
maxRetxThreshold ENUMERATED { t1, t2, t3, t4, t6, t8, t16, t32 }}
DL-AM-RLC ::= SEQUENCE {整理：kangguoying202006106
sn-FieldLength SN-FieldLengthAM OPTIONAL, -- Cond Reestab
t-Reassembly T-Reassembly,整理：kangguoying202006106
t-StatusProhibit T-StatusProhibit}
UL-UM-RLC ::= SEQUENCE {整理：kangguoying202006106
sn-FieldLength SN-FieldLengthUM OPTIONAL -- Cond Reestab}
DL-UM-RLC ::= SEQUENCE {
sn-FieldLength SN-FieldLengthUM OPTIONAL, -- Cond Reestab
t-Reassembly T-Reassembly} 整理：kangguoying202006106
SN-FieldLength UM ::= ENUMERATED {size6, size12}整理：kangguoying202006106整理：kangguoying202006106
SN-FieldLength AM ::= ENUMERATED {size12, size18}
T-PollRetransmit ::= ENUMERATED {ms5, ms10, ms15, ms20, ms25, ms30, ms35, ms40, ms45, ms50, ms55, ms60, ms65, ms70, ms75, ms80, ms85, ms90, ms95, ms100, ms105, ms110, ms115, ms120, ms125, ms130, ms135,ms140, ms145, ms150, ms155, ms160, ms165, ms170, ms175, ms180, ms185, ms190, ms195,
ms200, ms205, ms210, ms215, ms220, ms225, ms230, ms235, ms240, ms245, ms250, ms300, ms350, ms400, ms450, ms500, ms800, ms1000, ms2000, ms4000, spare5, spare4, spare3, spare2, spare1}
PollPDU ::= ENUMERATED { p4, p8, p16, p32, p64, p128, p256, p512, p1024, p2048, p4096, p6144, p8192, p12288, p16384, p20480, p24576, p28672, p32768, p40960, p49152, p57344, p65536, infinity, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare1}整理：kangguoying202006106
PollByte ::= ENUMERATED {kB1, kB2, kB5, kB8, kB10, kB15, kB25, kB50, kB75,kB100, kB125, kB250, kB375, kB500, kB750, kB1000,kB1250, kB1500, kB2000, kB3000, kB4000, kB4500,kB5000, kB5500, kB6000, kB6500, kB7000, kB7500,mB8, mB9, mB10, mB11, mB12, mB13, mB14, mB15,mB16, mB17, mB18, mB20, mB25, mB30, mB40, infinity,spare20, spare19, spare18, spare17, spare16,spare15, spare14, spare13, spare12, spare11,spare10, spare9, spare8, spare7, spare6, spare5,spare4, spare3, spare2, spare1}整理：kangguoying202006106
T-Reassembly ::= ENUMERATED {ms0, ms5, ms10, ms15, ms20, ms25, ms30, ms35,ms40, ms45, ms50, ms55, ms60, ms65, ms70,ms75, ms80, ms85, ms90, ms95, ms100, ms110,ms120, ms130, ms140, ms150, ms160, ms170,ms180, ms190, ms200, spare1}
T-StatusProhibit ::= ENUMERATED {ms0, ms5, ms10, ms15, ms20, ms25, ms30, ms35,ms40, ms45, ms50, ms55, ms60, ms65, ms70,ms75, ms80, ms85, ms90, ms95, ms100, ms105,ms110, ms115, ms120, ms125, ms130, ms135,ms140, ms145, ms150, ms155, ms160, ms165,ms170, ms175, ms180, ms185, ms190, ms195,
ms200, ms205, ms210, ms215, ms220, ms225,ms230, ms235, ms240, ms245, ms250, ms300,ms350, ms400, ms450, ms500, ms800, ms1000,
ms1200, ms1600, ms2000, ms2400, spare2, spare1}
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