Keysight (Agilent) E5505A Data Sheet

Agilent E5500 Series
Phase Noise Measurement Solutions

Technical Overview and Data Sheet

Model E5505A configurations

Carrier frequency ranges

50 kHz to 6.6 GHz
50 kHz to 18 GHz
50 kHz to 26.5 GHz

• Flexible set of measurements and
configurations, widest offset range,
and best reputation for the R&D
workbench or production floor

• Measurements on one-port VCOs,
DROs, crystal oscillators, and syn­thesizers and on two-port devices,
including amplifiers and converters,
plus CW, pulsed and spurious
signals

• Absolute and residual phase noise,
AM noise, and low level spurious
signals

• Easy configuration for various
measurement techniques,
including PLL/reference
source, residual and FM
discriminator methods

• Wide offset range capability,
from 0.01 Hz to 100 MHz

• Architecture combines
standard instruments, phase
noise components, and PC
software flexibly, allowing re-use of
assets (proprietary architectures are
less flexible because the reference
sources and analyzers selected can
limit phase noise measurements)

Offset frequency ranges

0.01 Hz to 2 MHz

0.01 Hz to 100 MHz

With over 35 years of low phase noise, RF design,

• E5500 software enables many
standalone instruments to work
together within a system

and measurement experience, Agilent solutions
provide excellent measurement integrity, repeat­ability, and accuracy.

Agilent E5500 Theory of Operation

The “phase detector with refer­ence source” technique is the most
general-purpose and cost-effective
measurement approach to measure
the single sideband (SSB) phase
noise characteristic of oscillators.
This technique demodulates the noise
sidebands of the device-under-test
(DUT) oscillator to a baseband signal
for a fast, easy measurement using
off-the-shelf baseband analyzers.

With the reference source and the
DUT in steady state quadrature, the
phase detector generates a baseband
signal proportional to the phase dif­ference of the two sources. When the
noise characteristics of the reference
source signal are less than the DUT
signal noise characteristics, the

resulting baseband noise signal is
effectively that of the DUT.

A narrow-band phase-lock-loop forces
the two phase detector input signals
into quadrature and allows the refer­ence source to track DUT frequency
drift for drift rates within the loop
bandwidth. Noise fluctuations within
the loop bandwidth are suppressed
by the operation of the phase-lock­loop. This suppression effect can be
independently measured and the noise
data corrected automatically by the
measurement software. Noise fluctua­tions outside of the phase-lock-loop
bandwidth are unaffected.

When the oscillator-under-test has
a frequency output in the microwave

frequency range, it is difficult to
find suitable, low noise, microwave
frequency sources to use as the
necessary reference signal. In this
case, the solution is to use a low­noise downconverter to translate the
DUT microwave output frequency to
a lower RF/IF frequency, allowing the
use of the same low-noise RF refer­ence sources described previously.

The phase noise of the RF reference
or the microwave downconverter
usually dominates the effective noise
floor of this phase noise measure­ment. The noise contribution of the
baseband test set is much lower than
either and typically does not factor
into the overall measurement noise
floor.

Simplified phase noise measurement diagram

2

Widest Measurement Coverage

The E5500 has been tailored to meet
the extensive needs of engineers,
providing the most flexible and best
measurements at the lowest possible
cost. The modular instrument archi­tecture takes advantage of standalone
instrumentation for superior frequency
offset range, broadest capability, best
sensitivity, and excellent overall value
for phase noise measurements. The
E5500’s low internal noise floor and
measurement flexibility let you mea­sure a wide variety of devices with
one system.

Ability to test a wide range of devices

The E5500 Series measures the
absolute, single sideband phase noise,
the absolute AM noise, and the low
level spurious signals of a wide range
of one-port production devices with
either CW or pulsed carrier signals:

• VCOs, DROs, and fixed oscillators

Measure AM noise directly

The E5500 Series can automatically
measure the AM noise of RF and
microwave devices. The internal
AM detector and DC blocking filter
provided within Agilent’s N5500A–001
measures AM noise on carriers up
to 26.5 GHz. AM noise of millimeter
frequency devices can be measured
with an external AM detector.

Additive noise measurements to
two–port devices

The E5500 Series also measures the
residual (additive) phase noise, AM
noise, and low level spurious signals
of two-port production devices with
either CW or pulsed carrier signals:

• High power amplifiers

• Frequency dividers

• Frequency multipliers

Measuring noise using the external noise
input port

• Crystal oscillators and clocks

• High frequency synthesizers

• Low noise DC supplies

Residual noise measurement of a two-port device

• Mixers

3

Most Flexible Measurement Solution

Superior frequency offset range

The Agilent E5500 comes standard
with the capability to measure from

0.01 Hz to 2 MHz of offset range

directly, or optionally measure offset
ranges to 100 MHz and beyond. The
wide offset range provides engineers
with more information on the test
device’s performance close-to-carrier
and far-from carrier. The E5500 pro­vides complete 0.01 Hz to 100 MHz
offset range measurement capabil­ity without the need for additional
baseband analysis hardware. A PC
digitizer, along with an optional broad­band RF signal/spectrum analyzer,
provides not only a complete phase
noise measurement solution, but the
signal/spectrum analyzer can also be
used for many other independent R&D
measurement functions. All of this
for a price you might expect to pay
for other, more limited, measurement
solutions.

Handles carrier frequencies to 26.5 GHz

The E5500 solutions can include a low
noise down-converter optimized for
their respective frequency ranges. For
example, the 18-GHz down-converter
has a minimum input frequency of
1 GHz allowing you to select an RF
reference source with a maximum

output frequency of 1 GHz. This
optimization helps reduce the total
solution costs for phase noise mea­surements because standalone low
frequency signal sources are lower
cost components. The addition of
low-noise RF reference sources and
microwave down-converters provide
a complete phase noise measure­ment solution for a wide range of
IF, RF, microwave, and millimeter
frequency oscillators. Some low noise
measurements could be configured
with the N5500A phase noise test
set’s optional 26.5 GHz input. This
requires a low noise microwave
reference source because the E5500
does not downconvert the signal.

Expand carrier frequencies to 110 GHz

For absolute measurement of phase
noise in the millimeter frequency
bands, add the appropriate Agilent
11970 Series millimeter harmonic
mixers to the E5500 solution with the

26.5-GHz microwave down-converter.
The down-converter provides the
high power, direct LO drive necessary
to down-convert millimeter signals.
The 45-dB variable gain IF amplifier
is available to amplify the IF output
of the harmonic mixer. The down­converter can also supply the DC bias
to the harmonic mixer if appropriate.

Wide choice of reference sources

The E5500 offers a wide choice of low
noise reference sources because this
system component is critical to the
overall phase noise measurement per­formance. One reference source might
be needed to measure the best close­to-carrier phase noise and another
reference could easily be used for
the best far from carrier phase noise
measurements. Unlike proprietary
architectures that limit your choice
to one or two reference sources, the
E5500 offers numerous reference
sources to fit your application. These
standalone instruments will provide
the best value and are easily reused
on your bench or in your ATE systems.

The E5500 phase noise test set and
downconverters have an internal
noise floor well below the noise of
most reference sources and do not
require special phase detectors to
lower the noise floor further. For
situations where standard RF signal
generators may not offer sufficient
measurement sensitivity, the E5500
series can use any voltage tuneable
source as a reference source. For
example, the N5508A is an ultra-low­noise fixed frequency source that has a
tunable option.

Block diagram for coverage up to 110 GHz

Use off-the-shelf RF signal generators or
your own low-noise source as the reference
source

4

Easiest Integration into the Production ATE Environment

The Agilent E5500 Series of phase
noise measurement solutions is tai­lored to meet the demanding needs of
production ATE. With test times of less
than 3 seconds (1 kHz to 100 kHz) and
less than 30 seconds (10 Hz to 1 MHz)
achievable, the E5500 Series meets
the high throughput and over-all, low
cost-oftest needs for today’s higher
volume devices.

Key features for ATE are:

• Quick and easy integration into
existing ATE systems using
standard instruments and
SCPI programming

• “Just-enough” measurement
performance because of E5500
configuration flexibility

• Lowest overall cost of measurement
by using standalone instruments
likely to be included in your ATE
system

A configuration for ATE consists of a
low noise baseband test set, a PC digi­tizer for baseband signal measurement,

and measurement software. The base­band test set provides all of the phase
detectors, amplifiers, filters, switches,
and attenuators necessary to measure
phase noise over the IF, RF, and
microwave frequency ranges directly.
The PC digitizer samples the baseband
noise signal and sends the digitized
data to the measurement software
for fast digital signal processing. The
measurement software provides all of
the operator interaction, measurement
coordination, calibration, data signal
processing, and data results. The
remote (SCPI) standard commands
programmable instruments program­ming interface client provides quick
and easy integration into new and
existing production test environments.

Quick and easy integration into your
ATE system

With a completely defined, industry
standard SCPI programming interface
client, the E5500 Series can be quickly
and easily integrated into your specific
ATE computing environment. If you
choose to configure an E5500 Series

solution to run on a separate computer,
initiate a measurement over LAN or
GPIB using the standard, remote,
phase noise SCPI command language.
Full measurement system control,
including capturing measurement
data, is included. If your production
ATE computing environment runs
under Windows®, a separate com­puter is not necessary. Simply initiate
a measurement using the multitasking
capability and the remote SCPI inter­face to communicate with the E5500
series measurement software running
concurrently on your ATE computer.
Data is available in two ASCII formats:
a spread sheet format and an XY
graph format. Other data translators
can be specified and provided.

Software summary

• Modular, object oriented, client/
server architecture

• Windows-compliant graphical user
interface and operating system

• Industry standard SCPI program­ming language

• Standard ASCII data formats

Integrating an Agilent E5500 solution into a production test environment

5

SENSe:NOISe:MEAStype ABSolute
CARRier:FREQuency:FIXed 10 MHz
REFerence:FREQuency:FIXed 10 MHz
SENSe:DETector:FREQuency 10 MHz
SENSe:DETector LFRequenc
SENSe:RANGe:OFFSet 10 Hz, 10 MHz
SENSe:RANGe:SEGTable:MEASurement:QUALity FAST
DISPlay GRAPh:TRANsform SSBNoise
INITiate:CALibrate
TTOTal?
*WAI
*STB?
CALCulate:VIEW:XYDATA
CALCulate:DATA:HEADer: POINts?
CALCulate:DATA?

A simple SCPI programming example