在LTE發(fā)展初期，大部分終端都是CAT3和4；網(wǎng)絡(luò)和終端側(cè)都支持2*2 MIMO;2017年后2天線已經(jīng)成為基本配置，以下已成為現(xiàn)網(wǎng)標(biāo)準(zhǔn)配置：整理：kangguoying20200710

•         2x2

•         4x2

•         4x4

•         8x2

整理：kangguoying20200710

        針對這些配置，網(wǎng)絡(luò)需了解UE的天線能力；而UE不需要了解網(wǎng)絡(luò)側(cè)，因為UE可應(yīng)用任何網(wǎng)絡(luò)的要求，由網(wǎng)絡(luò)計算出UE的能力，為其進(jìn)行MIMO配置;另一種方法，也就是UE可以計算出網(wǎng)絡(luò)側(cè)的天線配置；整理：kangguoying20200710

 1.終端對eNB的MIMO識別

        終端通過對“PBCH CRC Mask”檢測獲得eNB使用的天線數(shù)量，但不能獲得eNB在發(fā)送“RRC連接建立和重配置”時使用的MIMO方式；整理：kangguoying20200710

 2.網(wǎng)絡(luò)對UE的MIMO能力識別

        網(wǎng)絡(luò)通過UE”Capability”字節(jié)獲得其MIMO能力；該字段是網(wǎng)絡(luò)向UE進(jìn)行能力查詢時UE”Capability”自其上報告的信息中獲得；在UE能力表中，我們可以找出其支持的layer數(shù)，通過這些信息網(wǎng)絡(luò)可以直接查到UE的MIMO能力；如果UE的能力支持layer2，則終端支持2*2和4*2的MIMO模式；如果支持layer 4，則UE支持4x4的MIMO模式;

整理：kangguoying20200710

3.實例整理：kangguoying20200710

3.1   2x2 TM3

| | +-antennaInfo ::= CHOICE [explicitValue] OPTIONAL:Exist

  | | | +-explicitValue ::= SEQUENCE [1]整理：kangguoying20200710

  | | |   +-transmissionMode ::= ENUMERATED [tm3]整理：kangguoying20200710

  | | |   +-codebookSubsetRestriction ::= CHOICE [n2TxAntenna-tm4] OPTIONAL:Exist

  | | |   | +-n2TxAntenna-tm3 ::= BIT STRING SIZE(2) [111111整理：kangguoying20200710

3.2 2x2 TM4

| | +-antennaInfo ::= CHOICE [explicitValue] OPTIONAL:Exist

  | | | +-explicitValue ::= SEQUENCE [1]整理：kangguoying20200710

  | | |   +-transmissionMode ::= ENUMERATED [tm4]整理：kangguoying20200710

  | | |   +-codebookSubsetRestriction ::= CHOICE [n2TxAntenna-tm4] OPTIONAL:Exist

  | | |   | +-n2TxAntenna-tm4 ::= BIT STRING SIZE(2) [111111整理：kangguoying20200710

3.3 4x2 TM3

 | | +-antennaInfo ::= CHOICE [explicitValue] OPTIONAL:Exist

  | | | +-explicitValue ::= SEQUENCE [1]整理：kangguoying20200710

  | | |   +-transmissionMode ::= ENUMERATED [tm3]整理：kangguoying20200710

  | | |   +-codebookSubsetRestriction ::= CHOICE [n4TxAntenna-tm4] OPTIONAL:Exist

  | | |   | +-n4TxAntenna-tm3 ::= BIT STRING SIZE(64)整理：kangguoying20200710

                              [1111111111111111111111111111111111111111111111111111111111111111]

3.4 4x4 TM3

 | | +-antennaInfo ::= CHOICE [explicitValue] OPTIONAL:Exist

  | | | +-explicitValue ::= SEQUENCE [1]整理：kangguoying20200710

  | | |   +-transmissionMode ::= ENUMERATED [tm3]整理：kangguoying20200710

  | | |   +-codebookSubsetRestriction ::= CHOICE [n4TxAntenna-tm4] OPTIONAL:Exist

  | | |   | +-n4TxAntenna-tm3 ::= BIT STRING SIZE(64)整理：kangguoying20200710

                              [1111111111111111111111111111111111111111111111111111111111111111]

 +-nonCriticalExtension ::= SEQUENCE [10] OPTIONAL:Exist整理：kangguoying20200710

    +-lateNonCriticalExtension ::= OCTET STRING CONSTRAINTED [0000000101101010] OPTIONAL:Exist

    | +-RRCConnectionReconfiguration-v8m0-IEs ::= SEQUENCE [01]整理：kangguoying20200710

    |   +-lateNonCriticalExtension ::= OCTET STRING OPTIONAL:Omit

    |   +-nonCriticalExtension ::= SEQUENCE [10] OPTIONAL:Exist整理：kangguoying20200710

    |     +-antennaInfoDedicatedPCell-v10i0 ::= SEQUENCE [1] OPTIONAL:Exist

    |     | +-maxLayersMIMO-r10 ::= ENUMERATED [fourLayers] OPTIONAL:Exist

    |     +-nonCriticalExtension ::= SEQUENCE OPTIONAL:Omit整理：kangguoying20200710

原文來自：http://www.sharetechnote.com/整理：kangguoying20200710