Transcript Trellis-Coded DUSTF Modulation with APSK Constellation

Applications of MIMO
최수용
[email protected]
http://web.yonsei.ac.kr/sychoi/
연세대학교 전기전자공학과
Vertical/Horizontal MIMO
Vertical Encoded 2x2 MIMO System
= Single CodeWord MIMO (SCW MIMO)
같은 FEC 및 modulation
Horizontal Encoded 2x2 MIMO System Uplink? Downlink?
= Multiple Codeword MIMO (MCW MIMO) : MU-MIMO
Antenna 마다 다른 FEC 및 modulation
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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SFBC
STBC (Space Time Block Code)
SFBC (Space Frequency Block Code)
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
2/21
Cyclic Delay Diversity (CDD)
3GPP Release 8 LTE 표준
채널의 심한 변화
Scattered frequency
selective fading
주파수 영역에서 인터리빙
Burst frequency
selective fading
연세대학교 전기전자공학과 최수용
주파수 코딩 이득 증대
Note 15. MIMO Applications
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다중반사파에대한이동통신기술의진화
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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AMS (Adaptive MIMO Switching)
 CQI (Channel Quality Index) : AMC
 PMI (Precoding Mapping Index) : Precoder
 RI (Rank Index) : Number of stream
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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MIMO 기법
Open/closed loop MIMO
Multicell MIMO,
COMP(cooperative
multi-point Tx & Rx)
– LTE-A
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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R8 LTE MIMO Design Principles
Anti-fading: TD(Transmit diversity) (and SM)
Enhance spectral efficiency: SM (TD and BF)
Enhance SNR: BF (and codebook-based precoding)
Channel adaptive: CL precoding, Rank adaptation
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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R8 LTE MIMO Summary
(Precoding vector switching)
(Time switched transmit diversity)
(Frequency switched transmit diversity)
(Demodulation)
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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LTE 물리채널별 MIMO 기술
Physical channel
Usage
Tx Diversity
SM-MIMO
CDD
Reference Signal
X
X
X
Primary, & Secondary
Synch Signal
X
X
X
Physical Broadcasting
Channel
System information
(Master information
Block)
O
X
X
Physical Control
Format Indication
Channel
Control Format
Indicator( Subframe마다
전송, OFDM symbol 수)
O
X
X
Physical Downlink
Control Channel
자원할당, HARQ 및
scheduling 정보
O
X
X
Physical Multicast
Channel
방송형 data
O
O
X
Physical Downlink
Shared Channel
Downlink user data
O
O
O
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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LTE DL Reference Signals Mapping
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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SFBC+FSTD
When the pilot density is same for data
transmitted on four antennas
When the pilot density for data transmitted on
different antennas is not same, e.g. pilot density
on group 1 (antenna 1 and 2) is not same with
that on group 2 (antenna 3 and 4)
When the pilot density is all different for
antenna 1,2, 3 and 4
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
11/21
DL Physical Channel Processing
Scrambling of coded bits in each of the code words to be transmitted on a physical
channel
Modulation of scrambled bits to generate complex-valued modulation symbols
Mapping of the complex-valued modulation symbols onto one or several
transmission layers
Precoding of the complex-valued modulation symbols on each layer for transmission
on the antenna ports
Mapping of complex-valued modulation symbols for each antenna port to resource
elements
Generation of complex-valued time-domain OFDM signal for each antenna port
*3GPP TS 36.211, Evolved Universal Terrestrial Radio Access (E-UTRA); physical Channels and Modulation, V8.6.0, March 2009
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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Layer Mapping for SM
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
13/21
Precoding for large-delay CDD
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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RI, PMI, CQI
Rank Indication (RI)
 Inform about the channel rank or, expressed differently, the number of layers
Precoder Matrix Indication (PMI)
 Provides a precoder matrix that should, preferably, used for DL transmission
 The reported precoder matrix should be determined assuming the number of
layers indicated by RI
 PMI is reported only in CL mode. In OL mode, the network instead selects the
precoder matrix to use according to a pre-defined rule.
 Network has 2 choices:
 The network may follow the recommendation from UE, in which case it only has to
confirm with 1 bit indicator in DL scheduling assignment.
 The network may select a different precoder. Then the precoder information needs to
be explicitly included in DL scheduling assignment.
Channel Quality Indication (CQI)
 A set of pre-defined MCS combinations
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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7 Tx modes are possible in PDSCH
PDSCH 안테나 전송 방식
Transmission Mode 1
한 개의 안테나를 통한 전송
Transmission Mode 2
Tx Antenna Diversity
Transmission Mode 3
Open loop SM-MIMO
Transmission Mode 4
Closed loop SM-MIMO
Transmission Mode 5
MU-MIMO
Transmission Mode 6
Closed loop Beam Forming
Closed loop rank 1
precoding
Transmission Mode 7
Open loop Beam Forming
UE-specific Reference
signal
연세대학교 전기전자공학과 최수용
Alamouti Coding
SFBC for 2 Tx antenna
FSTD for 4 Tx antenna
CQI, PMI, RI feedback
from UE
Note 15. MIMO Applications
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7 Tx modes are possible in PDSCH
Mode 1 : Single-antenna port; port 0
 DL transmissions using a single Tx antenna at eNB :일반적인 SIMO 전송
Mode 2: Transmit diversity
 DL transmission using Alamouti-like transmit diversity schemes (SFBC)
 The number of layer is equal to the number of antenna ports
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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7 Tx modes are possible in PDSCH
Mode 3: Open loop spatial multiplexing
 Transmit different streams of data simultaneously on the same RB(s) by
exploiting the spatial dimension of the radio channel. These data
streams belong to the same user
 Up to 2 codewords transmissions with “no PMI feedback”
 Exploits CDD in DL transmissions
 Up to 4 layers and 4 antennas
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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7 Tx modes are possible in PDSCH
Mode 4: Closed loop spatial multiplexing (SU-MIMO)
 Transmit different streams of data simultaneously on the same RB(s) by
exploiting the spatial dimension of the radio channel. These data
streams belong to the same user.
 Up to 2 codewords transmissions with “RI and PMI feedback”
 Exploits CDD in DL transmissions
 Up to 4 layer and 4 antennas
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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7 Tx modes are possible in PDSCH
Mode 5: Multi-user MIMO (MU-MIMO)
 Transmit different streams of data simultaneously on the same RB(s) by
exploiting the spatial dimension of the radio channel. These data
streams belong to different users.
 Also known as downlink SDMA
 Single codewords and single Layer per user (UE reports only PMI, no
RI is reported)
 Up to 4 Tx antennas at eNB
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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7 Tx modes are possible in PDSCH
Mode 6: Closed loop Rank=1 precoding
 Same as Mode 4 with Rank restriction 1
 No Rank reports are required
Mode 7: Single antenna port; port5
 Same as Mode 1 using UE-specific Reference Signals instead of Cellspecific Reference Signals (with the help of sounding reference signal)
연세대학교 전기전자공학과 최수용
Note 15. MIMO Applications
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