Post on 04-Oct-2021
transcript
System Architecture
2018 Fall Intro LTE
Chap6:LTE Air Interface
Tomohisa Wada
Information Engineering
1
Air Interface Protocol Stack
2
IP: Internet protocol
RRC: Radio Resource Control protocol
PDCP: Packet Data Convergence protocol
RLC: Radio Link Control protocol
MAC: Media Access Control protocol
Transport Channel Processor
-> Error management
Physical Channel Processor
-> OFDMA, SC-FDMA, MIMO
Analogue Processor
-> analog conversion, real wave
Logical Channels
3
<- connection related
<- Broadcast Master
Information Block (MIB),
System Information Block (SIB)
DTCH and DCCH are major Channels
Transport Channel
4
UL-SCH and DL-SCH are major Channels
<- PCCH<- MIB
<- + SIB
<- Multimedia Broadcasting Service
<- Initial Connection Request
Physical Data Channel
5
Control Information
6
Transport Channel Processor composes several types of control information
to support low-level operation of physical layer as shown in Table 6.4.
Physical Control Channel
7
Physical Signal
8
LTE Uplink Information Flows
9
LTE Downlink
Information Flows
10
FDD Frame
11
1 frame = 10 ms = 10 sub-frame
1 sub-frame = two slots
1 slot = 500 us = 0.5 ms = 7 OFDM symbols or 6 OFDM symbols
500 us
1slot
TDD Frame
12
1st and 5th sub-frame is always DL
Guard period
Resource Block
13
Resource block is minimum unit for one user.
1slot (0.5 ms) X 180KHz (12 sub-carriers)
<- QPSK(2bit), 16QAM(4bit), 64QAM(6bit)
Bandwidth Options
14
MIMO DL modes
15
DL FDD Frame Structure
Example
16
3MHz 15 Resource Blocks
Normal CP : 5 OFDM in one slot
1st antenna port of two
Not used x will be RS of 2nd antenna port
UL FDD Frame Structure
Example
17