Overview of AMC in LTE Gwanmo Ku Adaptive Signal Processing and Information Theory Research Group Jun. 15, 2012 Outline 2/17 LTE Basic Why LTE LTE Network / Resources / Frame Structure LTE in US (Verizon) AMC in LTE Why AMC? Channel Condition : CQI Reporting MCS associated with CQI References 2/11 LTE Basic Why LTE? 4/17 Continuity of Packet Switch Higher Data Rate Competitiveness Optimized System QoS of 3G System LTE High Spectral Efficiency Very Low Latency Support of Variable Bandwidth (Reference: http://www.3gpp.org/LTE) LTE Network 5/17  L TE Network Internet * EPC : Evolved Packet Core * E-UTRAN : Evolved Universal Terrestrial Radio Access Network * UE : User Equipment * eNB : evolved Node B LTE Resource (Unit) 6/17  P hysical Resource Block (PRB)  The Smallest User Assignment Resource Unit (12 Sub-carriers) Frequency (#Subcarriers) 180 KHz PRB (12 Sub-carriers) 0.5 ms Time (6 or 7) (# Symbols) LTE Resource (Parameters) 7/17 DL/UL Parameters System BW [MHz] 1.4 3 5 10 15 20 # Resource Blocks 𝑵 6 15 25 50 75 100 𝑹𝑩 ∆𝒇=𝟏𝟓𝑲𝑯𝒛 2048 FFT Size 𝑵 ∆𝒇=𝟕.𝟓𝑲𝑯𝒛 - 4096* ∆𝒇=𝟏𝟓𝑲𝑯𝒛 12 # Subcarriers per RB 𝑵 𝒔𝒄 ∆𝒇=𝟕.𝟓𝑲𝑯𝒛 - 24* ∆𝒇=𝟏𝟓𝑲𝑯𝒛 72 180 300 600 900 1200 # Use d Subcarriers 𝑵 𝒖 ∆𝒇=𝟕.𝟓𝑲𝑯𝒛 - 2400* Sampling Rate [MHz] 30.72 Subcarrier Spacing ∆𝑓 = 15 𝑘𝐻𝑧 UL/DL, ∆𝑓∗ = 7.5 𝑘𝐻𝑧 DL only Parameters used by Verizon in US (Reference : 3GPP TS 36.101 V8.15.0 (2011-09)) LTE Frame Structure 8/17 Frame Structure Type 1 : FDD Frame Structure Type 2 : TDD 5ms Switch 10ms Switch (Reference : 3GPP TS 36.211 V8.9.0 (2009-12)) LTE Service in US (Verizon) 9/17  L TE Operating Band (Verizon) FDD Uplink FDD Downlink E-UTRA LTE Band 700 800 750 MHz 699 716 729 746 756 758 768 777 787 788 798 Band 13 Band 13 757 776 C C Verizon LTE Plan in US FCC Upper 700 MHz Block C FCC Band in US  BW 10 MHz, 600 Sub-carriers (50 PRBs) 2/11 Adaptive Modulation & Coding