Cours on Microwav Masurmnts Vctor Ntwork Analyzr Prof. Luca Prrgrini Dpt. of Elctrical, Computr and Biomdical Enginring Univrsity of Pavia -mail: luca.prrgrini@unipv.it wb: microwav.unipv.it Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 1
ummary Vctor ntwork analyzr VNA calibration tchniqu Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 2
Vctor ntwork analyzr cattring paramtrs ar typically masurd, at microwav frquncis, with a ntwork analyzr (NA). Ths instrumnts hav found wid application sinc th mid to lat 1970 s. Vctor ntwork analyzr: masurmnt of magnituds and phass of th -paramtrs calar ntwork analyzr: masurmnt of only th magnituds of th -paramtrs Most NA s masur 2-port paramtrs. om masur 4 and 6 ports. Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 3
Vctor ntwork analyzr Hwltt-Packard 8510 digital procssing & instrumnt control port 1 tst cabls port 2 IF procssing mm-wav tst st microwav tst st frquncy gnrator Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 4
Vctor ntwork analyzr Hwltt-Packard 8510 a 1 b 1 port 1 tst cabls port 2 b 2 Attnuator (optional) a 2 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 5
VNA Block Diagram RF ourc IF IF a 3 LO ourc b 0 IF IF b 3 Port - 1 Port - 2 Cabl a 1 b 2 Cabl b 1 a 2 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 6
VNA Block Diagram: Forward Dirction Port - 1 Port - 2 a 1 b 2 RF ourc LO b 1 a 2 LO A/D A/D A/D IF IF DP DP DP b 0 b 3 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 7
VNA Error Modl Forward Dirction a L -1 Port - 1 Cabl & Connctor a 1 b 2 Cabl & Connctor Port - 2 L C L C M M 1 M C M C 11 21 22 M C M C M 2 L 1- L C 12 L C L -a0 L -b0 L 1-a0 L 1-b0 b 1 a 2 L 2-b3 N La0 N Lb0 N Lb3 L a0-b3 1+A a0 +N Ha0 1+A b0 +N Hb0 1+A b3 +N Hb3 IF IF b 0 b 3 Branchs With No Labl = 1 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 8
VNA Error Modl Forward Dirction Error Modl Dfinitions a 1 = Incidnt ignal at Port-1 b 1 = Rflctd ignal at Port-1 a 2 = Incidnt ignal at Port-2 b 2 = Transmittd signal at Port-2 a = ourc Port = Masurd Incidnt Port b 0 = Masurd Rflctd Port b 3 = Masurd Transmittd Port L -1 = Loss from ourc to Port-1 L 1- = Loss from Port-1 to ourc L -a0 = Loss from ourc to L -b0 = Loss from ourc to b 0 (Dirctivity) L 1-a0 = Loss from Port-1 to (Dirctivity) L 1-b0 = Loss from Port-1 to b 0 L 2-b3 = Loss from Port-2 to b 3 L a0-b3 = Loss from to b 3 (Lakag) L C = Loss of Cabls 11 = Rfl Cof of at Port-1 21 = Forward Trans Cof of 12 = Rvrs Trans Cof of 22 = Rfl Cof of at Port-2 M 1 = Match at Port-1 M 2 = Match at Port-2 M = Match of ourc M C = Match of Cabls N La0 = Low Lvl Nois at N Lb0 = Low Lvl Nois at b 0 N Lb3 = Low Lvl Nois at b 3 N Ha0 = High Lvl Nois at N Hb0 = High Lvl Nois at b 0 N Hb3 = High Lvl Nois at b 3 A a0 = Dynamic Accuracy at (Linarity) A b0 = Dynamic Accuracy at b 0 (Linarity) A b3 = Dynamic Accuracy at b 3 (Linarity) Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 9
Rducd Error Modl Forward Dirction Port - 1 a 1 30 b 2 Port - 2 10 21 32 00 11 11 22 22 b 3 01 12 b 0 b 1 a 2 Branchs With No Labl = 1 Dirctivity 00 L L b0 a 0 Lakag L a b 30 0 3 Rflction Tracking 10 01 L L L 1 1b 0 a0 L L L 1 1 b0 2 L a0 Transmission Tracking 10 32 L L L 1 2b3 a 0 Port-1 Match M L L 11 2 L 1 1 a0 a0 Port-2 Match M 22 2 Thr ar also Errors causd by th Convrtr, IF, Cabls and Connctors Thr ar also ix Trms in th Rvrs Dirction Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 10
Improvmnts with Corrction ERROR REMOVED ERROR REMAINING Port Match Dirctivity Tracking Main Lakag Paths Nois and Rsiduals Rcivr Linarity Drift aftr Error-Corrction tability aftr Error-Corrction Rpatability of Connctors, tc Lowr Lvr Lakag Paths Errors of Calibration tandards Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 11
Improvmnts with Corrction Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 12
On Port: 3-Trm Error Modl b 0 Prfct Rflctomtr b 0 Error Adaptr 3 Error Trms a 1 b 1 Port - 1 1 00 11 10 01 b 0 a 1 00 = Dirctivity 11 = Port Match ( 10 01 ) = Tracking b 1 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 13
On Port: 3-Trm Error Modl Masurd Actual M = b 0 = 00-1 - 11 = M - 00 M 11 - = 00 11 - ( 10 01 ) For ratio masurmnts thr ar 3 rror trms Th quation can b writtn in th linar form 00 + M 11 - = M With 3 diffrnt known, masur th rsultant 3 M This yilds 3 quations to solv for 00, 11, and 00 + M1 11 - = M1 00 + M2 11 - = M2 00 + M3 11 - = M3 Any 3 indpndnt masurmnts can b usd Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 14
12-Trm Error Modl b 0 a 1 Forward b 0 b 1 Prfct Rflctomtr Error Adaptr,a 3 Rvrs a 3 a 2 b 3 b 2 b 3 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 15
12-Trm Error Modl b 0 a 1 Forward Modl Prfct Rflctomtr b 0 Forward Error Adaptr b 1 [] a 3 a 2 b3 b 2 b 3 6 Error Trms b 0 a 1 Rvrs Modl Prfct Rflctomtr b 0 Rvrs Error Adaptr b 1 [] a 3 a 2 b3 b 2 a 3 b 3 6 Error Trms Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 16
12-Trm Error Modl FORWARD MODEL Port - 1 a 1 30 b 2 Port - 2 1 00 11 10 01 11 21 22 12 10 32 22 b 3 b 0 b 1 a 2 00 = 11 = ( 10 01 ) = Dirctivity Port-1 Match Rflction Tracking 11M = b 0 = 00 + ( 10 01 ) 11-22 1-11 11-22 22 + 11 22 ( 10 32 ) = 22 = Transmission Tracking Port-2 Match 21M = b 3 = 30 + ( 10 32 ) 21 1-11 11-22 22 + 11 22 30 = Lakag = 11 22-21 12 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 17
12-Trm Error Modl b 0 REVERE MODEL Port - 1 Port - 2 a 1 b 2 21 23 32 11 11 22 22 23 01 12 1 b 1 a 2 33 b 3 a3 03 33 = 11 = ( 23 32 ) = Dirctivity Port-1 Match Rflction Tracking 22M = b 3 a 3 = 33 + ( 23 32 ) 22-11 1-11 11-22 22 + 11 22 ( 23 01 ) = 22 = Transmission Tracking Port-2 Match 12M = b 0 a 3 = 03 + ( 23 01 ) 12 1-11 11-22 22 + 11 22 03 = Lakag = 11 22-21 12 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 18
Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 19 D D M M M M M M M M 11 11 00 10 01 22 33 23 32 22 22 21 30 10 32 12 03 23 01 21 21 30 10 32 22 33 23 32 22 22 22 22 33 23 32 11 00 10 01 1 1 1 D D D M M M M M M M 11 11 21 30 10 32 12 03 23 01 12 12 03 23 01 11 00 10 01 11 11 11 00 10 01 11 22 33 23 32 22 21 30 10 32 1 1 1 M 12 03 23 01 22 11 12-Trm Error Modl
12-Trm Error Modl Calibration TEP 1: Calibrat Port-1 using On-Port procdur olv for 11, 00, & ( 10 01 ), Calculat ( 10 01 ) from TEP 2: Connct Z 0 trminations to Ports 1 & 2 Masur 21M givs 30 dirctly TEP 3: Connct Ports 1 & 2 togthr 22 = 11M - 00 11M 11-10 32 = ( 21M - 30 )(1-11 22 ) Us th sam procss for th rvrs modl Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 20
Elctronic Calibration tandards Dav Blackham & Kn Wong lid 21 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 21
Elctronic Calibration tandards Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 22
Elctronic Calibration tandards Elctronic Calibration tandards ar Transfr tandards Dfinition: Dvics that drivd thir charactristics from masurd data rlativ to primary or physical standards or othr transfr standards. Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 23
Accuracy of Error Corrction Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 24
Accuracy of Error Corrction Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 25
Accuracy of Error Corrction Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 26
Accuracy of Error Corrction Rsidual Errors OL Fixd Load OL liding Load TRL TRM Dirctivity d -40 db -52 db -60 db -40 db Match m -35 db -41 db -60 db -40 db Rflction Tracking t ±.1 db ±.05 db ±.01 db ±.01 db lid 27 Microwav Masurmnts 2015/16 Prof. Luca Prrgrini Vctor Ntwork Analyzr, pag. 27