TD-LTE --- China Telecom system 4G 3G TD-LTE TD-LTE TI TD-LTE TD-LTE ( 5bit/S/Hz; 2.5bit/S/Hz) ( :100Mbps :50Mbps) (100ms 10ms ) 1.4MHz;3MHz;5MHz,10MHz,15MHz,20MHz 2011 2 7 TD-LTE (GTI) 48 27 38 TD-LTE ( ) TD-LTE TD-LTE, TI 1 TD-LTE TD-LTE, 190MHz(2500-2690) TD-LTE ( F+A 1880-1920MHz,2010-2015MHz), ; F EVM
1.1 1 modulator (demodulator) 1) 2) ADC DAC TD-LTE ADC ADC 3) / 4) ADC DAC / 5) DPD DPD 1) 2) DAC ( ) DAC 3)
MCGSM www. EET-china.com 1.2 1 1) 2) 3) ADC 4) DAC DAC ( ) 1) ADC TD-LTE 190MHz 2) DPD 3) 1.3
1 DAC ADC : 1) 2) 3) 4) ADC TD-LTE : 1) DAC ADC 2) 3) DPD TD-LTE 2 TD-LTE TD-LTE, 3GPP TS 36.104 TDLTE / unwanted emission; 2.1
TD-LTE 8 20W 43dBm 3GPP +/-2dB, +/-2.5dB, +/-1dB, TD-LTE 190MHz +/-1dB 190MHz DAC +/-0.5dB TI DAC34H8X+TRF3705 +/-0.5dB 2.2 / TD-LTE TD-LTE / 3GPP -85dBm/MHz, -85dBm/MHz=-(85+10*lg10^6)=-145dBm/Hz, DAC -155dBm/Hz 2.3 EVM( ); 2.3.1
3GPP, (1ms) +/-0.05ppm TD-LTE 2.3.2 EVM( ) 3GPP 2-3% EVM : 1 CFR ( ), PA DPD EVM EVM CFR EVM CFR EVM 2 7 EVM (2) A: I/Q db
EVM B: EVM C: EVM D: Ɵ EVM G EVM, (5) EVM
2.3.3 www. EET-china.com TD-LTE 3GPP 65ns, 30ns, DAC DAC FIFO DAC 2.4 Un-wanted emissions( ) Un-wanted emissions 10MHz 10MHz UMTS 2110-2170MH 2100-2110MHz 2170-2180MHz 2.4.1 Operating band unwanted emissions Operating band unwanted emissions Un-wanted emission DPD DPD
FCC 1MHz 22dBm/MHz 3GPP cat A 1MHz -11dBm/MHz beam forming, 9dB 1MHz -20dBm/MHz 20W 43dBm 20MHz TD-LTE 3GPP 0-1MHz: 43dBm-10*log (18MHz)-(-11dBm/MHz) =40.5dBc 1MHz-10MHz: 43dBm-10*log (18MHz)-(-13dBm/MHz) =42.5dBc 10MHz: 43dBm-10*log (18MHz)-(--15dBm/MHz) =44.5dBc DUC CFR, 2.4.2 ACLR( ) ACLR 3GPP cat A -45dB -13dBm/MHz cat B 45dB -15dBm/MHz ACPR
PA driver, DAC ACLR ACLR PA driver, OIP3, : 1 ACPR=IIM3I-3dB 2 ACPR=IIM3I-9dB 4 ACPR=IIM3I-12dB IM3 OIP3 OIP3 OIP3 2.4.3 Transmitter spurious emissions( ) 9KHz 12.5GHz 3GPP -96dBm-10*log(100KHz/Hz)=-146dBm/Hz, ; -98dBm
www. EET-china.com ( ), PLL 2.4.4 5MHz E-UTRA 43dBm-30dB=13dBm +/-12.5MHz,+/-7.5MH,+/-2.5MHz 6 3 TI TD-LTE TI (DAC+, ) 3.1 DAC+ 190MHz BW DPD 600MHz DAC 750MHz
(750*0.8=600MHz) DAC 750*2=1.5Gpbs, DAC34SH84 1.5GHz, 600MHz : 13dB DAC+ :-22dBm/MHz-13dB-(-43dBm-(-14dBm))-10lg1MHz=-152dBm/Hz DAC34SH84-156dBm/Hz, TRF3705-157dBm/Hz, -153dBm/Hz : 8 DAC34SH84+TRF3705, 8 DAC34SH84+TRF3705 SFDR 20MHz, 10% DAC34SH84+TRF3705 SFDR [43dBm-10lg (18MHz)]-[(-22dBm)-(10lg1MHz)]-10lg0.1=63dB
9 DAC34SH84+TRF3705 SFDR TI DAC34SH84+TRF3705 TD-LTE 4 1 3GPP TS 36.104 V82.0 (2008-05) 2: WCDMA EVM