vector network analyzer fundamentalspersonal.rhul.ac.uk/ukap/042/anritsu/2-vna fundamentals.pdf ·...

VECTOR NETWORK ANALYZER

FUNDAMENTALS

WHAT ISA

VECTORNETWORK ANALYZER

?

SCALAR NETWORK ANALYZER

MICROWAVESIGNAL

MICROWAVEDETECTOR

DETECTOROUTPUT

VOLTAGE

DETECTOR OUTPUT VOLTAGE ISPROPORTIONAL TO SIGNAL AMPLITUDE.

VECTOR NETWORK ANALYZER

A VECTOR NETWORK ANALYZER IS A TUNED RECEIVER

MICROWAVESIGNAL

INTERMEDIATEFREQUENCY (IF)

TUNABLELOCALOSCILLATOR

GREATER DYNAMIC RANGELESS SENSITIVITY TO INTERFERING SIGNALS

VECTOR NETWORK ANALYZER

SOURCE

TEST SET/RECEIVER

DIGITAL SECTION

PHASE CAPABILITYMAKE POSSIBLE:

• Phase measurements• Smith chart• Time Domain• Group delay• Vector error correction

RECEIVER TECHNOLOGY

• Frequency conversion• Magnitude and Phase

Measurements• Wide dynamic range• Harmonic rejection• Low noise

VECTOR NETWORK ANALYZER

SPLITTER

MICROWAVESOURCE

DUT

SYNC.DET.

L. O.

SYNC.DET.

TAN-1 I/R

TAN-1 I/R

R2 + I2

R2 + I2

RE

IM

IM

RE

MAG.

TEST CHANNEL

PHASE

REFERENCECHANNEL

PHASE

MAG.

BASIC SYSTEM

SOURCE LOCK

MICROWAVESOURCE

1STLO.

ERRORAMP

PHASEDET.

1STI.F.

2NDLO.

2NDI.F.

3RDLO.

3RDI.F.

XTALREF

I.F. AND M'WAVE SOURCE PHASE LOCKEDTO CRYSTAL REFERENCE

SOURCE BECOMES SYNTHESIZED

FREQUENCY ACCURACYVERSUS

RESOLUTION

TEST SET

0-40SDM

P2 BIAS

P2P1

P1 BIAS

RA

TA

0-70

R F R F

RB

TB

RF IN

b1 In a1 In

FOUR CHANNELS

HARMONICGENERATOR

POWERAMP

CHANNELS

TB

TA

RA

RB

1ST IF89MHz

2ND IF2.5MHz

3RD IF80KHz IF OUTPUTS

TB

TA, RA

RA, RB

3RD LO

SOURCELOCK

2ND LOPHASE LOCK

1ST LOPHASE LOCK

FREQUENCY CONVERSIONEACH CHANNEL

A TRIPLE CONVERSION RECEIVER

MAGNITUDE & PHASE INFORMATION PRESERVEDTHROUGH LINEAR FREQUENCY CONVERSION

MICROWAVESOURCE

1STLO.

1STI.F.

2NDLO.

2NDI.F.

3RDLO.

3RDI.F. SYNC.

DET.DUT

DIGITAL SECTION

• Mathematical Operations• Human Interface• Display information• Data I/O

BASIC MEASUREMENT PRINCIPLES

INCIDENTENERGY

REFLECTEDENERGY

TRANSMITTEDENERGY

REFLECTION COEFFICIENT=

TRANSMISSION COEFFICIENT=

DUT

REFLECTED ENERGYINCIDENT ENERGY

TRANSMITTED ENERGY

INCIDENT ENERGY

S-PARAMETERS

S12 REVERSE TRANSMISSION

PORT 1 PORT 2

S11 FORWARDREFLECTION

S22 REVERSEREFLECTION

S21 FORWARD TRANSMISSION

DUT

PHASE MEASUREMENT

REFERENCE PLANE

• Defined at the test port measurement plane

Magnitude = 0 dBPhase = 0 degrees

• Established during calibration

ELECTRICAL DELAY

+180

+90

0

-90

-180

1.1 1.2 1.3 1.4 FREQUENCY,GHz

MEA

SUR

ED P

HA

SE

PATH LENGTH COMPENSATION

01.1

1.2

1.3 1.4FREQUENCY,GHz

+2

+1

-1

-2

RES

ULT

AN

T PH

ASE

DISPLAY PARAMETERS

• Magnitude(Log Magnitude, dB)

• Phase(Linear Phase, degrees)

POLAR DISPLAY

-90

180

90

0

SMITH CHART

50

INDUCTIVE

CAPACITIVE

Ω

FOUR CHANNEL DISPLAY

• Independent channels• Up to 8 traces• S-parameters• User-definable parameters

CAN CORRECT FOR THE FOLLOWING SIX ERROR SIGNALS IN BOTH THE FORWARD AND

REVERSE DIRECTION

• Transmission Frequency Response• Reflection Frequency Response• Directivity• Source Match• Load Match• Isolation between ports

THIS ADDS UP TO 12 TERMS

VECTOR ERROR CORRECTION

MAGNITUDE AND PHASE OFEACH ERROR SIGNAL IS DERIVED

THE RESULTANT ERROR VECTOR IS REMOVEDMATHEMATICALLY, HENCE 12-TERM ERRORCORRECTION

MAG

PHASE