文档介绍:Differential Analysis on of TD-LTE and LTE FDD
TD-LTE System, HAO Dandan
Outline
Executive Summary of Differential Analysis
Key Differential Analysis
Algorithm Analysis
Requirements for next step Cooperation
Note: This PPT is based on the version of 3GPP 36 series released in Dec. 2008.
Executive Summary of Differential Analysis for Physical Layer
Physical Layer Differential Analysis
No.
Item
Description
Different or Not
1
Duplex Mode
Operation mode FDD/TDD
Yes
2
Frequency Band
Different Operational bands for FDD and TDD at the global view
Yes
3
Supported Bandwidth
Supported scalable bandwidth ( MHz)
No
4
Frame Structure
Type 1 is for FDD, while type 2 is for TDD
There are 3 special field, DwPTS, GP, UpPTS in type 2 radio frame
No
5
Time Slot Structure
Both FDD and TDD have 1ms subframe consisting of 2 timeslot
No
6
Multiple Access
DL: OFDM; UL: SC-FDMA
No
7
MIMO
Spatial Multiplexing: FDD & TDD
Transmission Diversity: FDD & TDD
Beamforming: high priority for TDD
Antenna Diversity: only optional for FDD
Different priority of different MIMO mode for FDD & TDD
Physical Layer Differential Analysis
No.
Item
Description
Different or Not
8
DL/UL Configuration & switch period
DL/UL configuration is one of TDD-only feature
Yes
9
UL-DL Frame Timing
0 Ts for FDD, while 614 Ts for TDD
Yes, different value
10
Modulation/Demodulation
BPSK, QPSK, 16QAM, 64QAM (Optional for UL)
No
11
Channel Coding/Decoding
Turbo coding etc.
Common for using TC
Differences in DCI/
12
UL Physical Channels Transmission & Format
PUSCH
PUSCH
No
13
H
Additional H formats for TDD mode (to be specified)
Yes, There’s TDD specific format
14
PRACH
Random access preamble types 0~3 are for both TDD and FDD, while type 4 is for TDD
Different PRACH configurations
Yes
15
UL Reference Signals
Both need support demodulation RS & sounding RS.
For TDD, SRS may be transmitted on UpPTS
Physical Layer Differential