MICROWAVENETWORK ANALYSIS APPLICATIONS:

NEW SOLUTIONSFOR OLDER CHALLENGES

Henri KomrijNetwork Mealurementl Divilion

1400 Fountaingrove ParkwaySanta ROIS, California 95401

RF & MicrowaveMeasurementSymposiumandExhibition

Flin- HEWLETTa:~ PACKARD

www.HPARCHIVE.com

ABSTRACT: This paper describes the development of new network analysis

measurement systems and techniques that can be applied to such diverse areas as

millimetric-wave measurements, in-fixture device characterizations, frequency-translation

device testing. and antenna-pattern measurements. System configurations are developed

and described. Included are discussions of new calibration standards and accuracy

enhancement techniques that provide substantial improvements in measurement

accuracy.

AUTHOR: Henri B. Komri~ Applications Engineer. Hewlett-Packard Network

Measurement Division, Santa Rosa, CA. He received a BS degree in electrical

engineering from the University of California at Los Angeles in 1985. With HP since

1985, he has supporled applicatiom for [he HP 8510 and HP 8753 network analyzer!l

and the HP 8757 scalar analyzer.

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,

Microwave network analysi~ has evolvedsignificalllly over the past twenty years.The latest development is Hewlen-Packcud's85 JOB network analyzer. This paper willdescribe the contributions of the HP 85 JOBboth in performance and in measurementaccuracy. Also presented will be newtechniques made possible by the advancesof the HP 8510B for measuringcomponents. antennas, and non-eoaxialdc\'ices.

"New Levels of Performanceand New Applications."

5751

HP 85108DESIGN GOALS:

The major design goals for the HP 851 OBare shown here and will serve as an outlinefor this paper. The first objective was tostay one step ahead of the needs intraditional network analysis applications.

• Improve HP8510 for all applications

( • Improve accuracy

• Expand into unique applications

• Provide upgrade path/backward

compatiblity for HP8S10A

5753A

The HP 85108 has a new, faster processorand enhanced algorithms which greatlyincrease measurement and data acquisitionspeed. For example, a 20] point data tracewith full two-port error correction applied.is displayed in under 500 milliseconds. Inaddition. time domain responses are updaleLlfrom 16 times (5] points) to 2 times (401points) fasler than the HP 851OA. HP-)Bdata transfer rates have doubled as well.Speed can be particularly important forapplications requiring "real-time"information.

* New Internal Com uter

BASIC MEASUREMENT IMPROVEMENT:

TlIM ....,

1000

aoo

eoo

«10

100

0,5754

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BASIC MEASUREMENTIMPROVEMENTS

INTERNAL STORAGE

• Over 1 Mbyte• Store 8 401 pt. full 2-port calibra1ions

5755

BASIC MEASUREMENTIMPROVEMENTS

EXTERNAL STORAGE

I­i ----,--

• No conl'oI~' n.-d.d J..::l-,--_==-• Cholc. 01 ml&a alorag. "nlta• T,a.aPO"abl. elala• Unllmlled alo,a;.

5756

BASIC MEASUREMENTIMPROVEMENTS

ARBITRARY FREQUENCY SWEEP MODE

Internal memory in the HP 85108 hasincreased from 256 Kbyte~ each of RAMand bubble to I Mbyte of RAM and 512Kbytes of EEPROM. This capability allowstorage of eight complete measurementsetups (including 40 I point. two-port. 12term error-eorrected data for eachmec1surement). Also, 801 point frequencyand time domain traces may be displayedsinlllll:lOeously. Trace memory has beenexpanded from 4 to 8 full traces. with up 1080 I points e.1ch. particularly useful formiltching applications.

An eXICrIlill disc drive interface hilS beenallllcd to the H P 851 on to complement 1hebuill-in t(ipe drive. Unlimited amOllnlS ofinstrumcnt states. calibration data. andmeasurement data can be stored to anuretrieved from an" HP-IB controllable lIi~c

drive with comlmind subset CS;80. withoutthe need for an external compUier. HPSeries 200/300 computer formats are usedfor eas) transpon of dC:lla.

Arbitrary frequency sweep mode has beenadded to the HP 85108 to allow testing tobe performed only at specified fre(!uencil:\.Desired frequcncies Ciln ~ cntcred into lhenetwork analyzer via front panel soflkey~.

Reduction of tcst time Illay be veryimponanl for high volume componenlmanufnlturers.

• __lly .~ '-1lC~a • "alar .all.;

5757

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, .

OTHER MEASUREMENTIMPROVEMENTS

• Smart marker functiona

• Enhanced line atretcher

• Analog copy output

HP 85108DESIGN GOALS:

• Improve HP8510 for all applications

* Improve accuracy

* Expand into unique applications

* Provide upgrade path/backward

compatiblity for HP8510A

BASIC MEASUREMENTIMPROVEMENT

* New calibration atand.rda

• New calibration technique.

Some other new enhancements of the HP851 DB for nel work measurements incluucsmilrt marker functions such as markersearch. an analog copy output for direcioutpul to a pattern recorder. and animproved line siretcher which compensale~

for waveguide dispersion. Electrical delilYin waveguide is calculated by the networ"analyzer using the following equation:

J.Dela y (seconds) =-;====~

c~ 1- (fco, f) 2

5758

The nexi major goal of the HP 85 JOB wa\to improve the accuracy of allmeasurements.

5753B

The HP 85JOA has allowed us to obsenoeconnector performance to levels ne 'erbefore seen. In some cases. the connector~

of the calibration standards are the primar~

limiting factor to achieving higher levels oferror-eorrected performance. Consequenll~.

a new "slotless" connector is beingintroduced which significantly improvesmeasurement accuracy. In addition, newaccuracy enhancement techniques havebeen established to provide even moreperformance.

5760A

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MEASUREMENT PROBLEM:SLOTTED CONTACT

* Conductor ratio "constant

* Impedance variations

5761

CENTER CONTACT INTERFACES.. '.~~r -5': : ••

:t : _i. ,!.:...,

.. ------------

.. ------------

.. ------------s·".· I I'U~""'·'f :'-1S·:;:: 21. !l::::r::; :'-1

5795

HP 8510B SOLUTIONSLOTLESS COAXIAL STANDARDS

* Conductor ratio = constant

* Constant impedance

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One major limitation in networkmeasurements is the quality of the standalused for calibration. When "sexed"connectors such as Type Nand 3.5 mOl aremated. the slotted female center conductorwill conform to the mated male center pin.Since the size of the male pin varies fromconnector to connector, impedance at thisinterface will vary from connection toconnection. Significant errors in calibrationand measurements result from suchvariation.

What is needed is a consistent contactindependent of male pin size. and where theinner contact shoulder is flush with theouter conductor. Shown is a measurementof return loss of a 3.5 mOl interface withvarying gaps between the shoulder of themale center contact and the end of thefemale center contact.

"Siotiess" connectors such as this one pro\"idea flush contact between the inner contnctshoulder and the outer conductor to the be'ltextent possible (.0001"). Also. the impedanceis independent of male pin size. When themale pin is inserted. the outside frontcorners of the inner contact fingers areforced to slide up on the inner 45 degreeslope of the pin. The integral spring in theback of the inner contact pro\"ide~ theproper contact pressure between the innercontact and the inner slope of the femnlepin. Thus. the ratio of the outer conductorto the inner conductor is constant re~ult inpin a consistent impeda nce.

SLOTTED VS SLOTLESS. .,.£f' : : ••

;t.: ••It::·

Shown is a measurement of SII of a slidingload with a "slotted" contact and with anslotless" contact. Notice the improvementin directivity.

'!'l"" -----~~-+----.:o'S:Ii :-!-----~.,....-~--~

:~r------'"--+-"""""--­I

r---f"~:::I: -----~,\----.,;.---

I: -----~---.;..-----.:

T. y------+-----J: ' ~ _

I .,..: '~.:£??,

~... I U..,., l>-t

.-:lJI " tl.er: :100-1

5796

HP 85108 SOLUTIONNew Siotiess Coaxial Standards

Shown i~ a photo of CI "slot less" open and <'l

"slotles~" short.

5763

PERFORMANCE IMPROVEMENT

3.5mm

STANDARD SLOTLESS

Effective Directivity 38 dB 44 dB

Source Match 30 dB 31 dB

iI Tracking ±.15 dB t .06 dB

"Slot less" standards increase measurementaccuracy considerably. For example. in 3.5mm. effective directivity is 44 dB, sourcematch is 31 dB, tracking is .06 dB, and thecharacterisitc impedance does not vary. Inaddition. 3.5 mm and Type N measurement~

are traceable to NBS based on the tightlycontrolled dimensions of the precision"slot less" standards.

* Traceablity to NBS through mechanical tolerances

5764

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MEASUREMENT REPEATABLITY

StandardFlange

HPPrecision

Flange

MORE PERFORMANCEFOR WAVEGUIDE

* Elimlnat.. cocking

* Eliminate. misalignment

5765

.u" .•• IIIIW)

'-" ....I" ..'

~

It.•

;

....-~...... ~~.. ~

a'''''' II .,'CP ••.••••• 7••• Dol.

5766

BASIC MEASUREMENTIMPROVEMENT

* New calibration standards

* New calibration techniques

5760B

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In waveguide measurements. flangeconnection repeatability is a major sourceof error after calibration. Each time theflange is connected. the waveguideapertures can be slightly misaligned fromthe previous connection. As a result, thecont:tct impedance varies from connectionto connection.To help alleviate this problem, precisionmillimeter-wave flanges were recentlyintroduced. By tightening the tolerance~ ofthe alignment pin locations and pindiameters. the possible misalignment of thewaveguide apertures can be minimized.Also. addition of precision locating pins anda lip around the perimeter of the flangehelps elimin:tte the possibility ofdis.1l'ranging the flanges.

Shown is a measurement of flangerepeatability made by m~suring a fixedload and storing the measurement data intothe displa y memory of the HP 85 JDB. Theflange was disconnected. reconnected. andmeasured again, subtracting the previousmeasurement using trace math. This proces\was then repeated several times. Thismeasurement shows a comparison of thestandard flange to the precision flange.Note that the repeatability error for theprecision flange is on the order of 80 10 90dB down, considerably less than the residuClIsystem errors after correction.

Now. let's look at a new calibrationtechnique for measuring noninserlabledevices. Other new calibration techniqueswill be presented later.

Most microwave devices are noninsertable(i.e., input and output connectors are samesex or of different families). Calibrating. (l

network analyzer for these types of de\'ice')has always been a challenge. Shown is anexample of a noninsertable device. a coaxto waveguide coupler.

t4lf""~"-'"

MEASUREMENT PROBLEMNONINSERTABLE DEVICE

5767

NONINSERTABLE DEVICE

TRANSMISSION CALIBRATION

OUT--;r-----< ( )»)----1) -~-f m m f

,. /--)~ " ' ./),...--J-

The problem with measuring noninsertnbledevices is that the ports of the test systemcan not be mated directly duringcalibration. Thus. an insened or switchedadapter is required for the transmissioncalibration step. When the switchedadapters are not perfectly matched. or theinserted adapter is not fully known.uncertainty is added to the measurement.

Can not directly mate test ports

* Insert adapter* Switch eQual adapters

5768

HP 8510B SOLUTIONNONINSERTABLE CALIBRATION

A new noninsertable calibration built intothe HP 8510B completely characterizes andrel1lo\'e~ the effects of an inserted orswitched adapter.

* Completely characterize in.erted adapter

* Completely characterize differencebetween .witched adapters

* Automatically remove adapter effectsfrom me.surement

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The calibrCltion begins by performing twofull two-port calibrations (one with theadapter on port J. and then with theadetpter on port 2). Now. enoughmeasurements are made to completelycharacterize (all 4 s-parameters) the adapter,A simplified I-port f10wgraph analysis isshown here. The network analyzermeasures the error~ introduced by theadapter and creates a cascaded error modcl.

Adapter

TIHP 85108

,J ,f,

'" ~, E.E.

·'--..... ..;;:1.:...-_...... --'-__--.#)

YOe-Embed Adapter

HP 8510B NONINSERTABLE CALHP 85108

J., ,...

~E" tEo.·

I'..5770A.B

NONINSERTABLE MEASUREMENT.,; • "1 ,., MA:'",If ." t ••

: , ..,.... waf. t>=wt Si ew Ett>C1-

Here is a measurement of coupling factorfor a coax to waveguide 10 dB coupler,One measurement was made using the insertadapter method while the other used thenoninsertable calibration method,Transitional adapters. like coax towaveguide, present significant discontinujtie~

and are difficult to characterize. Thenoninsenable calibration, however. allowsus to see the true response of the test de\'iccby completely removing the adapterresponse.

~•••- ;; ••ttl"" :-.S·::JJ" ~•••••••", ':;"',

5771

HP 85108DESIGN GOALS:

• Improve HP8510 for all applications

Network analyzers have traditionally beenused for measuring components, Anothermajor goal of the HP 8510B was to expandthe use of network analyzers into uniqueand demanding component applicationsincluding frequency translation de\'ices.millimeter-wave devices. antennas. andfixtured devices.

• Improve accuracy

• Expand into unique applications

5753C

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ENHANCED APPLICATIONCAPABILITIES

1) Components

2) Antennas

3) Semiconductor Devices

MEASURING FREQUENCYTRANSLATION DEVICES

MIXERS

Let's look at making some measurements on',0me of these unique de\'ice~.

5772A.

We'" start by seeing how a networkanitlyzer mec1sures a frequency tra nslit t iondevice such as a mixer. Todit)'. there arerequirements for mixers that are matchedaccording to their amplitude and phaseresponse.

5773

MIXER MEASUREMENTCONSIDERATIONS

Source 1IF

LO'

~SOU••• 2

Receiver

A mixer has been a difficult device tomeasure on a network analyzer. First. tv. 0

sources are needed and must be controlled.Plus. the source frequencies differ from thereceiver frequency. In the past, an externillcomputer was needed to simultaneouslycontrol the two sources and the receiver inorder to make mixer measurements.

* Need to control 2 sources* Source fre~uencies • receiver fre~uency

* Compare conversion loss and phase

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HP 85108 SOLUTIONMULTIPLE SOURCE CONTROL

5775

The !lystem control capability of the HP8510B IUI!l been expnnded to measurementsystems that require multiple RF sourcesand for measurements of devices theltperform frequency conversion. Buill-instimulus control has been extended tocoordinate independenr control of thefrequency and power level of up to twosignal sources and the receiver frequ~ncy.

The from panel menu structure shown herl'accepts entry of these frequencies for theprimnry (test or RF) and secondary (LO)sources as well as the receiver (IF). Thi!lmultiple source control mode may be usedin any application where two source\and or the receiver must be operated atdifferenr frequencies.

. HP '511"

HP 85108 MIXER TESTMultiple source control allows sweptmea\lIrements of mixer amplitude and pha,l'without an external computer. In thi~

set-up. measurements are made relati\e to ;lreference mixer. which is used to provide nreference signnl at the same frequency asthe test signal. The RF ranges from 2 to 8GHz as the LO sweeps from 2.1 to 8.1 GHi'..The IF ill held constant at 100 MHz.

H' .510 Sy.'.m I ••

~~ HP 13411

.; JI~ t

c. I .~~

Ae'.r.nee ~4 ....

'~---"'tIIt>-e '. T••, WI •• ' A

... Or-----oT••~ MI." B

• A,terlftCI mi•• , 0""" Jacka ret.'tl"tCI chlnnel

• ""'IlI" "'11.1' A - ltor. Ga:a Into m,,,,ory• ......"',• ..,i •• , • - dlta/memory

5776

MIXER MEASUREMENT RESULTS....... '''' ..1 I., ...-.G w..~l"lIII2'

.., •• .. ..- 1.1·1.' .' •.•• "

Shown are the results of 3 mixer amplitudeand phnse m;ltching measurement. First.mi\er A ill measured and the resu/t!l storedinto memory. Next. mixer B is measuredand its data subtracted from memory usingtrace math. This may be repeated tocompare several mixers. In this example.the mixers are matched within 1 dB and 5degree!l.

• ,. " " c.-.~ CIJoo,

5777

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MEASURING mm-WAVE DEVICES94 GHz FILTER

5778

HP 8510A ormm-WAVE BLOCK DIAGRAM

II I

, i ; I --i....!.-LI I~ ......,.. i ':"-:0 ; 'I', "I: I I '" .. IIlIOA I c........ ! ...tOll

, LO Slg~.1 SO</,et 0' ~ Conl,olle,', - 2 'i. ~Iwo'kI I 'i "_II --' : A".lyze,

5779A

Multiple source control also proves useful inmeasuring millimeter-wa\'e de\'ices such a~

this 94 GHz bandpass filler.

Wilh the HP 8510A, a millimeter-wavesystem block diagram looked like this. Acomputer was needed to control bothsources and receiver frequencies.

HP8510B mm-WAVE BLOCK DIAGRAM26.5 - 100 GHz (Multiple Source Control)

..miNte'-....lie".' Sol/,ee

5779B

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With the HP 85108, a computer is nolonger required since the analyzer cancontrol both sources over its system bus.

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HP8510B mm-WAVE BLOCK DIAGRAM

26.5 - 60 GHz (External Phase Lock)

Milh",,'.r-"VI fiO ...., ,S"".I Source -L I I :

~ (;?j ,:::.. --';;:;-0:' II;I IY\;>'- ,:1,

I 47 1;. ;-,.. ; )' I iDlIT~1 ,!

L_' "'. 1', Mill_I.,·_.. Teel Sel I: I

: i

: I ....'I t ~1'

I, " 1-:& .. u_'~ I' :2~' ~"I I~) I~ I ...,oe,

I:LO Sig"", Source ~ I Conlroller; r ~ ~ NelworkI _... L--.....; : A".lynr

5779C

94 GHz FILTER MEASUREMENT-11 1_, MAG .,~ '., IIUrrGIiIW'" t.. .. ...,. I.' ..

f _.:.J:~ .... ~ ... 1:.:,.:~

s· ...· I! ••••••~1t CJI-o.,S'l'CP 11••••••t.i' CJooI

5780

ENHANCED APPLICATIONCAPABILITIES

1) Components

2) Antennas

3) Semiconductor Oevices

5772B

·14-

For HP 8510B based millimeter-wansystemll up to 60 GHz. an HP8350B sweeposcillator may be used as the LO in place ora synthesizer. This significantly lowen thesystem cost. The HP 8510B\ external phaselock mode extends the phase lock loop ofthe receiver through the DC FM input ofthe sweeper.

This (relce shows the insertion loss of the 9..tGHz filter lO be about I dB and return 1m..to be about 40 dB at 94 GHz. b'en in thi ..frequency range. over 80 dB of dynamicrange can be realized.

Multiple source control can also be uti~jzed

for antenna measurements. In addition.several other new capabilities of the HP85 I OB will help in measuring antenna!.

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..

, .MEASURING ANTENNAS

• Far-field patterns• Near-field patterns

5788

We'U concentrale on a far-fieldmeasurement here although the discussionapplies to near-field measurements as well.By far-field we mean that lhe source andtesl antennas are far enough apan [(2D)*~

lambdCl} thClt a planClr waveform is incidenton the tesl antenna. Thus. the radiationpaltern of the anlenna undergoes very littlt'cha nge. Nea r-field measurements ta keplClce from 2-10 wavelengths away fromthe source antenna.

- ;. -

HP 85108 FAR FIELD MEASUREMENTBLOCK DIAGRAM

Io~,ce

A"'e"ne

',,/; , ! 'ha..... lock

___~' -.,'__-..1' HP 83~OB IYneSya'e", ... ~__-...=L~::":""'-_,.'~

• Wllfl,ple a",,'ct c"""ol

• "'",ottal>lt 1..: _I.

• I'vllClamenla' ",,",ng

5789A

Here is a typical far-field measurementblock diagram. To perform a patternmeasurement, the RF source is set to a CWfrequency and the anlenna is rotated whilea receiver measures the signal at the outputof the antenna under test. Multiple sourcecontrol allows independent control of theRF and LO. For high sensitivity, the testport!l may be remoled up to 150 feet andfundamental or harmonic mixers used todowncom'en the microwave frequency to ;t

20 MHz IF. Built-in external phase loc"allows a sweep oscillator LO source to bephase locked for remote downcon\'ersion orthe test and reference signals. This mixing.process occurs at the receive antennaoutpul.

HP 85108 FAR FIELD MEASUREMENTBLOCK DIAGRAM

We can automate our antenna range withthe addition of an external computer tocoordinate antennCl pattern measurement!lwith antenna position. \\lith external triggermode. the analyzer can be triggered to ta"cdata as the tesl antenna is rotated. The highspeed data collection capability of Fasl C\\'mode. greater than 1000 measurements persecond. is ideal for high volume datarequirements. The data. both amplitude andphase. correspond precisely with antennaazimuth and elevation.

tel MU,

""'OB I"

-.c....All""".T••,

""".....1

• , ...."et t"""• '.a, ew_t

5789B

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EXAMPLE PATTERN MEASUREMENT

B"e.:le.~a "'c""'"5.~ ~~z. G.t.~. 0'

•

\

\ Jx~

_I", .n

" . .., .. ....,.•••• 1M

5790

RCS MEASUREMENTS

Shown is an example pattern measured 011

the HP 85108. Analog copy output alJow~

for direct pattern recording.

Network analyzers are also well suited asreceivers for Radar Cross Section (RCS)measurements. In RCS measurements. weare interested in how big something looks toa radar signal.

HP 85108 IMPROVEMENTSFOR RCS MEASUREMENTS

• Built-in responaeliaolation calibration

• Range• External phase-lock• Oata acquisition apeed

.....rce

~> ... ~. ..- ..- .... .... Res

With external mixers and a sweep escalatorLO acting as our "test set", we can achieveoutstanding meCl\UrCment sensitivity. SO J

points provide Jong. range. high resolutionmeasurements. 1n addition, a newResponse/Isolation calibration is built intothe HP 85108 to characterize and removelow level test chamber reflections. UJingFast CW mode, single point measurementscan be made and transferred to an extern,,1computer in less that I millisecond per point.Ramp sweep measurements can be madeusing the HP 8511 A as our test set.

5792

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. .Next. lel\ 100" at using a network an(llyzn10 I11l\ke meaSlIremelllS of non-eoaxialde,"ice'l like semiconduclOrs.

ENHANCED APPLICATIONCAPABILITIES

1) Components

2) Antennas

3) Semiconductor Oevices

5772C

CHARACTERIZINGSEMICONDUCTOR DEVICES:

FIXTURED TRANSISTOR

5782

PROBLEM:• Remove effects of fixture

SOLUTION:• Calibrate in fixture

PROBLEM:• Quality loads and ahorta difficult to make

NEEO ALTERNATE CALIBRATION METHOD

5783A.B.C

-17-

AcclIr<ltcly charllcterizing such de\"ices hilsO1lw<I ys been difficult. Let's take a typic.,1~illll\lion: a fixture i~ needed to conneci theco;nial pon\ of a network all(llyzer 10 (Imicroslrip \ub\trale. on which the de\"ice i~

mounted.

The problem i~ to remove the effecI\ of thefixllIre from the measurement. The mostdirect calibration method is to calibr(lte (Itthe DUT illtcrf<lcc. Known in-fixturestandards. however. arc not alwaysavail<lble or are difficult to make. Atechnique using derived models. whichrepresent the fixture's respon\e"de-embedded" from the de\"ice dal<'l. hasbeen used in the past. This technique.however. requires a computer and thoroughknowledge of the fixture.

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HP8510B SOLUTIONTRL CALIBRATION

* Calibration based on Zo of line

* Reflect need not be perfect

* Length of line need not be known

5784

TRL CALIBRATION

'lIe'IO'"

5785A.D.C

EXAMPLE TRL MEASUREMENT.,) • "1 ••• ~... ·11 ...'I.' ../II; -lLNZUCJi' ,. F TiCP&::

~ I I J I

• 1

... .,.,. 1 SN•••••• 1>0 •• "CP 'I 0-.

5786-J 8-

A new calibration technique has beendeveloped in the HP 8510B for measuringin-fixture devices, called TRL (Thru.Reflect. Line). TRL is ideal for calibratingin dispersive media such as microstrip wherequality opens. shorts. and loads are difficultto ma ke. TRL. however. is a genera Icalibration technique which equally extend~

to coaxial measurements as well. Ir is basedon the Zo of the Line. The "Reflect" andlength of line need not be known precisely.Thus. the standard!l are more physicallyrealizable and fewer standard!l are needed.

By men suring 2 different length Zotransmission line!l. and any reflecti\'e (Je\'ice.a full two-port. error-corrected calibrationis completed. Generally speaking. all of thetwo-port error terms can be grouped intoeight individual terms. Four measuremelllsare made by both the thru and the linewhile the reflect performs twomeasurements. Thi!lleave~ us with 10equations and 8 unknowns. more thanenough information to solve for our errorterms. The two additional unknowns rna \'be the leng.th of the line and the impedtlllccof the reflect Further information can befound in reference #9.

Here is the measured tr:\Osmission responseof a microcircuit low pass filter. Onemeasurement was made using aconventional open/short/load calibration althe fixture interface. Note that the effect~

of the fixture are in our measurement. Th...other measurement was made using a TR Lcalibration.

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USING TRL in 7mm COAX

i STANDARD TRL

, Effactiva Diractivity 52 dB 60 dB

I60 dBI Source Match 41 dB

I

I Tracking i.OS dB .01 dB

As mentioned above, TRL can be used incoa xia I and wa veguide measurements a!lwell. The HP 8510B currently providesstandards for TRL calibrations in 7 mm.providing 60 dB directivity and port matchand less than .0] dB tracking error.

5787

SLIDING LOAD CAL (7mm) TRL CAUBRATION (7mm)SHOIlTED 10 eM ""lIIlINE &ItOI'ITED 10 CM ""RUNf

:r.••••• ­.r_ all .,._~ .....-

Shown i!l a measurement of a 7 mm 10 emnirline terminated in a short circuit firstmeasured with a sliding load calibration andthen with a TRL calibration. Note thereduction of ripple for the TRL case.

s I I-

\i V

, -V\J\ r ,., ,., b '" .'

\ V \,' I \ i b"" '"V V \. ,j

r.· ........., ..,'"71'_"'_

r ..· ._ .r"? I ........' .

5797

HP 85108DESIGN GOALS:

* Improve HP8510 for all applications

* Improve accuracy

The final major goal of the HP 851 OB wasto protect the invest ment customers ha \'emade into the HP 851 OA. Backwardcompatibility and a migration path weredesigned into the HP 85 JOB from the sta rl.For fUl1her information on how to upgradean HP 8510A to an HP 8510B, see yourlocnl HP sales representative.

* Expand Into uniqua applications

* Provide upgrada pathlbackward

compatiblity for HP8510A

5753D

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References

1. Fitzpatrick, Jim and Williams, Joe; "Measuring NoninsertableDevices With An ANA", Microwave Systems News, June 1981

2. Boyles, John; "Far-Field Antenna Measurements with The HP 8510Network Analyzer", Hewlett-Packard RF and Microwave Symposium,1986

3. Hewlett-Packard Co., HP 8510D Data Sheet

4. Hewlett-Packard Co., liP 85103A Data Sheet

5. Hewlett-P~ckard Co., Product Note 8510-1

6. Hewlett-Packard Co., Product Note 8510-2

7. Dildine, Bob; "Measurement Considerations For Network AnalysisAt MillimeLer Frequencies", Hewlett-Packard RF and MWSymposium, 1986

8. Curran, Jim; "Network Analysis Of Fixtured Devices",Hewlett-Packard RF and MW Symposium, 1986

9. Rytting, Doug; "An Analysis of Vector Measurement AccuracyEnhancement Techniques", Hewlett-Packard RF and MW Symposium,1982

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