Keysight Technologies Multiport and Multi-Site Test Optimization Techniques

June 2015

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Today’s Presenter

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• Graduate of Oregon State University

with an MSEE

• Ph.D. from Leeds University

• Keysight Technologies (formerly Agilent

and Hewlett-Packard)

• One of only five Keysight Fellows

• Senior R&D engineer in the Component

Test Division

• Principle contributor to the HP 8753

and PNA VNA family

• He has received 25 patents related to

this work

• Author or the “Handbook of Microwave

Component Measurements”

Dr. Joel Dunsmore Keysight Fellow

Component Test Division R&D

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Agenda

– Introduction

– Optimizing Multiport Testing

• Types of Multiport Solutions

• Comparing Multiport Solutions

• Multiport Calibration

– Multi-Site Techniques for Improving Throughput

• Hardware Considerations and Limitations

• Accelerating Multiport Testing

• Multi-Display / Multi-User

– Summary

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Industry Trends

• Multiple functions integrated into a single component

• Increasing need to drive down costs while increasing throughput

• Multiport testing without sacrificing accuracy

Markets Wireless Aerospace & Defense

Segments High-volume manufacturing test Maintenance, depot-level testing

Applications Handset

component test

Device Test Cellular ATE Systems MilCom

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Defining Multiport and Multi-Site

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Key Features

• Simultaneous measurement of

different DUTs

• Parallel testing for higher

throughput

Multi-Site Testing

DUT #1 DUT #2

DUT #3

Key Features

• Greater than 4 ports

• Single connection to device-

under-test (DUT)

Multiport Testing

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Agenda

– Introduction

– Optimizing Multiport Testing

• Types of Multiport Solutions

• Comparing Multiport Solutions

• Multiport Calibration

– Multi-Site Techniques for Improving Throughput

• Hardware Considerations and Limitations

• Accelerating Multiport Testing

• Multi-Display / Multi-User

– Summary

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Types of Multiport Solutions

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Simple Switching Test Sets

Simple Switching

Block Diagram Features

• VNA Signals distributed via RF

switches in an external switch

matrix.

• Sequential 2-port measurements

with VNA receivers.

• Either solid-state switches or

electro-mechanical switches

• Low-cost multiport solution

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Types of Multiport Solutions

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Full Crossbar Switching Test Sets

Full Crossbar

Block Diagram Features

• Similar to simple switching test

set except:

o Any 2 ports on DUT may be

tested

o Full 2 x N port error

correction

o Unused ports must be

terminated

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Types of Multiport Solutions

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Extension Test Sets

Extension Test Set

Block Diagram Features

• Directional coupler on every port

• Only Source and receiver

switching

• Full N x N port error correction

• Better stability and performance

• Switches still impact dynamic

range

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Keysight M937xA PXIe VNA

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Drive Down the Size of Test

2-port VNA in one slot

32-port Configuration

Features

• Full 2-port VNA in one PXI slot.

• World’s fastest PXI VNA

• 300 kHz up to 26.5 GHz

• Same measurement science as

the trusted PNA/ENA

• Up to 16 VNA modules in a single

chassis for up to 32-port fully

corrected multiport measurements

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Types of Multiport Solutions

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True Multiport w/ PXI VNA

True Multiport

Block Diagram Features

• Synchronized signals distributed

and captured with multiple

receivers.

• Simultaneous measurements

using multiple VNA receivers.

• No degradation in performance

as external switching not

required Port 1

R1

A

Port 2

R2

B

Source

Port 3

R1

A

Port 4

R2

B

Port 5

R1

A

Port 6

R2

B

…

Synchronized

Module #1 Module #2 Module #3

Synchronized

Source Source

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Example 6-Port Measurement of 2x4 Way Splitter

Keysight

Confidential 12

Isolation depends on good match on all ports

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Flexible, Scalable, Re-Configurable

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What You Need, Where You Need It

• Increase the number of

test ports or frequency

anytime you need

• Easily reconfigure your

test environment

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Flexible, Scalable, Re-Configurable

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No need to reboot or reconnect to re-configure.

Just select the

number of

modules you want

to use.

Multiport modules

have to be in

sequential slots.

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Comparing Multiport Solutions

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Number of Measurement Sweeps for 8-Port DUT

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Comparing Multiport Solutions

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Number of Measurement Sweeps

Improve throughput by reducing the number of required sweeps

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Comparing Multiport Solutions

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Dynamic Range

20-dB wider dynamic range allows for a 100-times faster speed

(with 100-times wider IFBW) for the same measurement result

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Comparing Multiport Solutions

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Temperature Stability

Good stability may reduce or eliminate the need for periodic recalibration;

total measurement time can be dramatically reduced.

Switched test set based VNA True Multiport VNA

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Multiport Calibration

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Calibration Can be Time Consuming & Confusing

# of Paths = (𝑁−1)(𝑁)

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Electronic Calibration (ECal)

Mechanical Calibration

Where N = # of

DUT ports

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Multiport Calibration

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ECal Simplifies Calibration – 10-Port Example

4-Port ECal

Connection: 4

Disconnection: 3

Connection: 3

Disconnection: 3

Connection: 3

Disconnection: 4

Total of 10x connections & disconnections of test cables

2-Port ECal

Connection: 2

Disconnection: 1

Connection: 1

Disconnection: 6

Connection: 6

Disconnection: 2

Disconnection: 1

Connection: 1

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Multiport Calibration

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Combining ECal with a Switch Matrix

• ECal characterized at the test ports

• Single connection calibration (but

with same # connects/disconnects)

• Adding switches creates similar

issues as switching test sets:

o Degraded performance at

higher frequencies

o Potential stability issues

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QSOLT Cal Reduces Reflection Cal Steps

– Makes mechanical calibration kits very easy to use (e.g. waveguide,

specialized connectors like blind mate).

– Your cal kit needs to have a known-thru defined to mate all the ports

to 1 port.

– Very simple to add a female-female thru to a cal kit if all the test

ports have male connectors.

– Just do a 1-port cal at port 1

– Then known-thrus from port 1 to each other port.

– That’s it!

Keysight

Confidential 22

One 1-port and N-1 Thru steps

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Agenda

– Introduction

– Optimizing Multiport Testing

• Types of Multiport Solutions

• Comparing Multiport Solutions

• Multiport Calibration

– Multi-Site Techniques for Improving Throughput

• Hardware Considerations and Limitations

• Accelerating Multiport Testing

• Multi-Display / Multi-User

– Summary

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Multi-Site Techniques for Improving Throughput

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Who Uses Multi-Site?

Application Examples

• High-volume manufacturing of

passive components

• SAW devices for mobile

handsets

• General-purpose components

(antennas, filters, cables, etc.)

• Full automated test equipment

(ATE)

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Multi-Site Parallel Testing Capability

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2-Port, 4-Port and Multiport

Key Features

• Simultaneous measurement of

multiple DUTs

• Configure multiple independent

VNAs in a single PXI chassis

• Each VNA can be 2 or more ports

• Synchronous or asynchronous

triggering

DUT

#1

DUT

#2

DUT

#3

DUT

#4

DUT

#1

DUT

#2 DUT

#3

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Hardware Considerations and Limitations

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• PXI Chassis – Each PXI VNA module

requires either hybrid or PXIe slot

• Controller – Embedded or external

not a bottleneck issue

• CPU / # of Cores – Depending on IF

bandwidth, this can become the

limiting throughput factor (next slide)

• Backplane Speed – Typicals of 4

GB/s easily handle the 100’s of MB/s

for VNA measurements

• Memory – Typically not a limitation

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Hardware Considerations and Limitations

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# of Cores vs. VNAs – Affect Depends on IFBW

Dual Core CPU, 100 kHz IFBW Dual Core CPU, 1 kHz IFBW

Quad Core CPU, 100 kHz IFBW Quad Core CPU, 1 kHz IFBW

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Accelerating Multiport Testing

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Example Multi-Site Application

S21

Sweep

PXI VNA (M937xA)

VNA with Switch Matrix

S21 Sweep

S43

Sweep

S65

Sweep

Switching

S43 Sweep

S65 Sweep

#1 #2

#3

6-port DUT

S21 S43

S65

Time

Multi-Site Operation with PXI VNA Cycle Time Comparison

Multi-site testing provides simultaneous sweeps of different measurement

paths (i.e. high-band & low-band) of multiport components

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Multi-Display / Multi-User

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Example Multi-Site Application

Key Features

• One controller, multi-site VNAs,

multiple test operators

• Configure multiple independent

VNAs in a single PXI chassis

• Example application: filter tuning

manufacturing

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Multi-Display / Multi-User

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Example Hardware Configuration

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Multi-Display / Multi-User

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Typical Microsoft Windows Multi-Display Setup

Setup Multiple Displays on Computer

Assign VNAs to

Displays

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Multi-Display / Multi-User

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Typical Microsoft Windows Limitations

Create Macros to Minimize

Operator / PC Interaction

Only One Click or Touch at a Time

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Summary

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• Keysight offers a broad range of multiport solutions that accurately

test your products while enabling you to drive down your costs and

increase throughput

• New multi-site capabilities and techniques further increase efficient

use of capital resources and test personnel

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For More Information

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www.keysight.com/find/pxivna

Available Literature

Multiport and Multi-site Test Optimization

Techniques Application Note 5992-0681EN

PXI VNA Brochure 5992-0098EN

PXI VNA Data Sheet M9370-90002

Multi-site

Installation & Demo

Multiport

PXI VNA Overview

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