LTE DCI

作者:神秘网友 发布时间:2020-04-16 15:23:40

LTE DCI

LTE DCI

LTE DCI has a lot more additional information in it. In addition to resource allocation, it can carry Power Control Command, CSI Report Request or CQI Report Request etc.

L1 signaling is done by DCI and Up to 8 DCIs can be configured in the PDCCH. These DCIs can have 6 formats : 1 format for UL scheduling, 2 formats for Non-MIMO DL scheduling, 1 format for MIMO DL Scheduling and 2 formats for UL power control.

DCI has various formats for the information sent to define resource allocations. The DCI formats defined in LTE are as follows. 

 

Usage

Major Contents

Format 0

UL Grant. Resource Allocation for UL Data

RB Assignment,TPC,PUSCH Hopping Flag

Format 1

DL Assignment for SISO

RB Assignment,TPC, HARQ

Format 1A

DL Assignment for SISO (compact)

RB Assignment,TPC, HARQ

Format 1B

DL Assignment for MIMO with Rank 1

RB Assignment,TPC, HARQ,TPMI, PMI

Format 1C

DL Assignment for SISO (minimum size)

RB Assignment

Format 1D

DL Assignment for Multi User MIMO

RB Assignment,TPC, HARQ,TPMI,DL Power Offset

Format 2

DL Assignment for Closed Loop MIMO

RB Assignment,TPC, HARQ, Precoding Information

Format 2A

DL Assignment for Open Loop MIMO

RB Assignment,TPC, HARQ, Precoding Information

Format 2B

DL Assignment for TM8 (Dual Layer Beamforming)

RB Assignment,TPC, HARQ, Precoding Information

Format 2C

DL Assignment for TM9

RB Assignment,TPC, HARQ, Precoding Information

Format 3

TPC Commands for PUCCH and PUSCH with 2 bit power adjustment Power Control Only

Format 3A

TPC Commands for PUCCH and PUSCH with 1 bit power adjustment Power Control Only

Format 4

UL Assignment for UL MIMO (up to 4 layers)

RB Assignment,TPC, HARQ, Precoding Information

 

There are two major factors to determine a DCI format for a specific situation as follows :

i) RNTI Type

ii) Transmission Mode

 

< 38.213-v14.6.0 Table 7.1-1: PDCCH and PDSCH configured by SI-RNTI >  

DCI format

Search Space

Transmission scheme of PDSCH corresponding to PDCCH

DCI format 1C

Common

If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used , otherwise Transmit diversity .

DCI format 1A

Common

If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used , otherwise Transmit diversity .

 

 

< 38.213-v14.6.0 Table 7.1-2: PDCCH and PDSCH configured by P-RNTI > 

DCI format

Search Space

Transmission scheme of PDSCH corresponding to PDCCH

DCI format 1C Common If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used, otherwise Transmit diversity
DCI format 1A Common If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used , otherwise Transmit diversity

 

 

< 38.213-v14.6.0 Table 7.1-3: PDCCH and PDSCH configured by RA-RNTI > 

DCI format

Search Space

Transmission scheme of PDSCH corresponding to PDCCH

DCI format 1C Common If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used , otherwise Transmit diversity
DCI format 1A Common If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used , otherwise Transmit diversity

 

 

< 38.213-v14.6.0 Table 7.1-5: PDCCH and PDSCH configured by C-RNTI> 

Transmission mode

DCI format

Search Space

Transmission scheme of PDSCH corresponding to PDCCH

Mode 1

DCI format 1A

Common and UE specific by C-RNTI

Single-antenna port, port 0 

DCI format 1

UE specific by C-RNTI

Single-antenna port, port 0 

Mode 2

DCI format 1A

Common and UE specific by C-RNTI

Transmit Diversity

DCI format 1

UE specific by C-RNTI

Transmit Diversity

Mode 3

DCI format 1A

Common and UE specific by C-RNTI

Transmit Diversity

DCI format 2A

UE specific by C-RNTI

Large delay CDD or Transmit Diversity

Mode 4

DCI format 1A

Common and UE specific by C-RNTI

Transmit Diversity

DCI format 2

UE specific by C-RNTI

Closed-loop multiplexing or Transmit Diversity

Mode 5

DCI format 1A

Common and UE specific by C-RNTI

Transmit Diversity

DCI format 1D

UE specific by C-RNTI

Multi-user MIMO

Mode 6

DCI format 1A

Common and UE specific by C-RNTI

Transmit Diversity

DCI format 1B

UE specific by C-RNTI

Closed-loop multiplexing using a single transmission layer

Mode 7

DCI format 1A

Common and UE specific by C-RNTI

If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used , otherwise Transmit diversity 

DCI format 1

UE specific by C-RNTI

Single-antenna port, port 5

Mode 8

DCI format 1A

Common and UE specific by C-RNTI

If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used , otherwise Transmit diversity 

DCI format 2B

UE specific by C-RNTI

Dual layer transmission, port 7 and 8  or single-antenna port, port 7 or 8

Mode 9

DCI format 1A

Common and UE specific by C-RNTI

Non-MBSFN subframe: If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used, otherwise Transmit diversity 
MBSFN subframe: Single-antenna port, port 7

DCI format 2C

UE specific by C-RNTI

Transmit diversity, port 7-8,  or dual layer transmission port 7-8 , if UE is configured with higher layer parameter semiOpenLoop, up to 8 layer transmission, ports 7-14  otherwise; or single-antenna port, port 7, 8, 11, or 13  if UE is configured with higher layer parameter dmrs-tableAlt, single-antenna port, port 7 or 8 otherwise

Mode 10

DCI format 1A

Common and UE specific by C-RNTI

Non-MBSFN subframe: If the number of PBCH antenna ports is one, Single-antenna port, port 0 is used, otherwise Transmit diversity 
MBSFN subframe: Single-antenna port, port 7

DCI format 2D

UE specific by C-RNTI

Transmit diversity, port 7-8,  or dual layer transmission port 7-8 , if UE is configured with higher layer parameter semiOpenLoop, up to 8 layer transmission, ports 7-14  otherwise; or single-antenna port, port 7, 8, 11, or 13  if UE is configured with higher layer parameter dmrs-tableAlt, single-antenna port, port 7 or 8 otherwise

 

 

< 38.213-v14.6.0 Table 7.1-7: PDCCH and PDSCH configured by Temporary C-RNTI>

DCI format

Search Space

Transmission scheme of PDSCH corresponding to PDCCH

DCI format 1A Common and UE specific by C-RNTI

If the number of PBCH antenna port is one, Single-antenna port, port 0 is used , otherwise Transmit diversity

DCI format 1 UE specific by C-RNTI

If the number of PBCH antenna port is one, Single-antenna port, port 0 is used , otherwise Transmit diversity

 

 

Any relations between DCI format and Layer 3 signaling message ?

 

Yes, there is a relationship. You have to know which DCI format is required for which RRC message. Following tables from 3GPP 36.321 shows the relationship between RNTI and logical channel and you would know which RRC message is carried by which logical channel. So with two step induction, you will figure out the link between RRC message and it's corresponding DCI format.

LTE DCI

 

For example, if you see the "Security Mode Command" message of section 6.2.2 of 36.331, it says

 

Signalling radio bearer: SRB1

RLC-SAP: AM

Logical channel: DCCH

Direction: UE to E-UTRAN

 

If you see the table, you would see this message is using C-RNTI. and you will figure out the possible candiates from table 7.1-5 of 36.213 and if you would have detailed information of the transmission mode, you can pinpoint out exactly which DCI format you have to use for this message for a specific case. Assuming TM mode in this case is TM1 and scheduling is dynamic scheduling, if you see Table 7.1-2 you will figure out that this is using C-RNTI. With this RNTI Type and TM mode, if you see table 7.1-5, this case use DCI Format 1 or DCI Format 1A.

 

 

LTE DCI相关教程

  1. (.NET进阶八)身份认证与授权/Authrize特性/Filter过滤器
  2. Vue之v-bind 与class、 style 、 computed 、 filters 的配合使
  3. angularjs 自定义filter的简单用法
  4. 布隆过滤器Bloom Filter算法的Java实现(用于去重)
  5. 牛X素材推荐之MaterialTextField
  6. filter(过滤器)与拦截器(AOP)区别
  7. 严重 Exception starting filter struts2 java.lang.ClassNotFou
  8. wiredtiger LSM trees bloom filter 设计原理