HP 8530A User manual

HP 8530A Microwave Receiver
User's Guide
ABCDE
HP P
art No
.08530-90016
Printed in U
.S
.A. F
ebruary 1994
Edition 3

Notice
This document contains proprietary information which is protected by copyright. All rights are
reserved. No part of this document may be photocopied, reproduced, or translated to another
language without prior written consent of Hewlett-Packard Company.
NOTE: Figure A-1 and Figure A-3 may be photocopied for use by the operator of the HP 8530A.
These gures may not be reproduced in other documents.
Hewlett-Packard Company
Santa Rosa Systems Division
1400 Fountaingrove Parkway
Santa Rosa, CA 95403, U.S.A.
c

Copyright 1991, 1992, 1993, 1994 Hewlett-P
ackard Co
.

Printing History
New editions of this manual will incorporate all material updated since the previous editions.
The manual printing date and part number indicate its current edition. The printing date
changes when a new edition is printed. (Minor corrections and updates which are incorporated
at reprint do not cause the date to change.) The manual part number changes when extensive
technical changes are incorporated.
Edition Date
Edition 1 October 1991
Edition 2 May 1992
Edition 3 October 1993
Manual Applicability
This manual applies directly to HP 8530A Receivers having an HP 85102R IF detector with
serial number prex 3238A or higher
,running rmware revision A.01.60
Safety
,W
arranty
,Regulatory Information
Safety
,warranty
,and regulatory information is supplied in the
HP 8530A Operating and
Programming Manual
.
W
arning
Before this instrument is switched on
,make sure it has been properly
grounded through the protective conductor of the ac power cable to a
socket outlet provided with protective earth contact.
Any interruption of the protective (grounding) conductor
,inside or
outside the instrument, or disconnection of the protective earth terminal
can result in personal injury
.
Caution
Before this instrument is switched on, make sure its primary power circuitry
has been adapted to the voltage of the ac power source.
Failure to set the ac power input to the correct voltage could cause damage to
the instrument when the ac power cable is plugged in.
iii

Instrument Overview
For more information on instrument controls, refer to \Front Panel Overview" in Chapter 1 and
\Front and Rear Panel" (Chapter 3) in the HP 8530A Operating and Programming Manual .
Figure 0-1. Instrument Overview
1. Display
The display shows measurement results and information messages. It also shows the names of
display softkeys
.
2. Softkeys
Many functions are controlled by softkeys. The title of each softkey is displayed on the display.
3. Entry Block
The entry block allows you to:
Enter numeric values using the keypad
4
0
5 through 4
9
5 , 4
+/-
5 .
Terminate values with appropriate units
4
G/n
5 (giga or nano),
4
M/u
5 (mega or micro),
4
k/m
5 (kilo
or milli),
4
x1
5 (basic units),
Increase or decrease values using the 4
85
and 4
95
keys, or using the rotary knob.
Correct errors using the 4
BACKSPACE
5 key.
Go up one level of softkey menus by pressing
4
PRIOR MENU
5
.
Turn OFF the active function by pressing
4
ENTRY OFF
5
.
iv

4. Status Display
This diagnostic/status display has the characters R L T S 8 4 2 1 in it. This display shows the
HP-IB Remote (R), Listen (L), or Talk (T) status, or shows if a service request \SRQ" has been
asserted (S). The numbers are self-test indicators.
5. Disc Drive
The disc drive accepts 3.5 inch DOS or Hewlett-Packard LIF format disks. Either 720 kB or
1.44 MB DOS disks can be used. The HP 8530A can show disc contents, format in DOS or LIF
format, delete les, or undelete the last le deleted (undelete works on LIF format discs only).
6. TEST Button
Causes self tests to be performed on the receiver.
7. AC power switch
This switch applies AC power to the Display section (turn this ON after the power switch on
the bottom box, see item 10).
8. Channel Select
The two channels make the same measurement, and then split the raw data results into two
parallel data processing pathways
.Each channel allows you to apply dierent instrument
features independently of the other channel. The nal results from each channel can be
displayed separately
,or they can be overlaid on the same graticule
.
9. Menus
Contains several major functions
4
CAL
5
controls three dierent types of measurement calibration.
4
DOMAIN
5
selects Angle
,Frequency
,or Time Domain operation.
4
DISPLAY
5 selects how many dierent measurements to display on the screen at once.
4
MARKER
5 allows you to use the marker features of the instrument.
10. AC power switch
This switch applies A
Cpower to the bottom section.
v

11. Instrument State
Contains several functions:
4
LOCAL
5 allows you to specify the HP-IB addresses of the receiver and \slave" instrument
connected to the System Interconnect. (The System Interconnect is the HP 8530A's
\personal" HP-IB bus. Any devices connected to it (printers, plotters, RF or LO sources) are
controlled exclusively by the HP 8530A.
4
SAVE
5 and 4
RECALL
5 allow you to save current measurement settings to one of eight save/recall
registers (for later recall).
4
USER PRESET
5 any setup you save in save register 8 becomes the \user preset" state. Any
time you turn power ON or press 4
USER PRESET
5 the settings stored in register 8 are retrieved.
12. Stimulus Block
The stimulus block controls most of the functions associated with the basic measurement setup.
Stimulus controls include:
Measurement start/stop or center/span values for angle, frequency,ortime.
P
ower levels for RF and LO sources
.
Sweep type (single sweep
,continuous sweeps
,ramp sweep
,stepsweep, and more).
Number of measurement points (in Frequency Domain), or increment angle (in Angle
Domain).
Frequency List mode setup
.
Trigger mode (internal, external, or HP-IB).
HP 85370A P
osition Encoder controls
.
13. P
arameter Block
This block selects which HP 8530A inputs to measure
.the main keys
4
P
ARAM 1
5
through
4
P
ARAM 4
5
select dierent \ratioed" measurements
.\Ratio" means that atest and reference
signal are measured, and then are mathematically divided together
.This method provides
very accurate measurement results
.Softkey menus under this block's
4
MENU
5
key allows you
to measure any of the four input lines without ratioing. (This feature allows you to check the
signals on the a1, a2, b1, or b2 input lines
.)
14. Auxiliary Menu
This area contains three control keys:
4
COPY
5
allows you to print or plot the measurement results
.
4
DISC
5
allows you to use the disc drive to save or load les
,format discs
,and perform other
disc-related functions
.
4
SYSTEM
5 contains instrument conguration functions
.Examples of the type of functions that
are controlled are: phase lock, IF calibration, power leveling, and multiple-source setup
(used when more than one source is connected to the HP 8530A). The system key also has
service menus that are used when troubleshooting the instrument.
15. Format Block
This block allows you to select dierent display formats such as Cartesian or polar
,in linear or
log format.
vi

16. Response Block
This block controls the following:
Display scale
Position and value of the reference line
Automatic display scale (autoscale)
Measurement averaging
Trace smoothing
Trace \normalization" (A specic point on the measurement trace is set to 0 dB, and other
portions of the trace are displayed relative to that.)
Magnitude slope and oset control
Phase oset control
Coaxial, waveguide, or user-denable electrical delay selection
17. 4
RESTART
5
This key is used when you are making swept measurements
.It aborts any measurement that is
in progress
.If you are using the single sweep mode
,
4
REST
ART
5
can start anew sweep
.
vii

Guide to this Manual
Figure 0-2. Sections in the HP 8530A User's Guide
.
Chapter 1. Getting A
cquainted with the HP 8530A receiver
Chapter 1provides aquick overview of the front panel controls
,display
,rear panel, and HP
8530A features
.
Chapter 2. Manual Measurement Examples
Chapter 2 shows very basic antenna and RCS measurement examples.
Chapter 3. Calibration
Chapter 3describes the calibration features of the HP 8530A, and how to use them.
Chapter 4. Measurement Tutorials
This chapter gives more in-depth information on making measurements
.F
eature choices are
explained so you can customize measurements to suit your needs
. This chapter also explains
how to use the HP 85370A P
osition Encoder
.
viii

Chapter 5. Common Measurement Tasks
Chapter 5 describes specic measurement tasks such as:
Finding boresight Using Markers
Determining 3 dB beamwidth Measuring depth of a null
Displaying data relative to the peak Displaying more than one trace
Using averaging Using frequency list mode
Chapter 6. Disc Drive Operation
Explains how to use the built-in disc drive to store and retrieve data, instrument state les,and
other types of information.
Chapter 7. Printing and Plotting
Describes how to output screen \snapshots" or tabular data to printer or plotter. A wide range
of HP printers and plotters are covered in detail.
Chapter 8. Making A
utomated Measurements
Chapter 8explains how to measure up to 5,000 points per second using F
ast CW mode
,and
how to use the F
ast IF Multiplexing. (F
ast IF multiplexing is similar to F
ast CW
,butallows the
receiver to automatically switch between dierent input ratios at each angle or frequency
point.)
Chapter 9. In Case of Diculty
This chapter explains:
How to solve common operation problems
What to do when specic error messages are displayed on the screen.
How to solve basic hardware problems
.
Appendix A, Optimizing Dynamic Range
Conguring the system for optimum dynamic range entails using the highest RF power settings
possible without overdriving the receiver. Appendix A explains how to congure your system
so optimum dynamic range is available.
Appendix B
,Compatible Instruments and P
eripherals
Lists compatible RF and LO sources, frequency converters
,positioner controllers
,printers
,
plotters, and monitors
.
Appendix C, Supplies
,A
ccessories, After-Sale Options
Lists commonly-needed supplies (plotter pens
, paper
, discs) and after-purchase options (time
domain option, rack-mount hardware, connector savers, and touch-up paint).
Appendix D
,Connector Care
Explains connector care techniques and cleaning procedures
.
ix

Other Manuals that Come with the HP 8530A
The following manuals are supplied with the HP 8530A:
Operating and Programming Manual
The Operating and Programming manual serves two purposes:
It provides in-depth reference information on front panel features, organized around the
front panel functional blocks.
It provides tutorial information on remote programming, with many HP BASIC examples.
Keyword Dictionary
The Keyword Dictionary explains:
The function of each front panel key or display softkey, organized by key/softkey name.
What each HP-IB programming code does, including syntax and programming sequence
details.
Front panel key/softkey and programming code descriptions coexist in the same section, in
alphabetical order
.
On-Site Service Manual
The On-Site Service Manual contains:
Installation
Troubleshooting
Performance tests and specications
Typeface Conventions
Bold Bold type is used for terms that are listed in the glossary.
Italics Italic type is used for emphasis and for the titles of manuals and other
publications. It is also used when describing a computer variable .
Computer
Computer type is used to depict HP-IB commands
.
Display
Display type is used to show messages which are displayed on the
receiver's display
.
4
Front P
anel Keys
5 Front panel keys are enclosed in boxes.
NNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Soft Keys
Soft keys are the keys on the right-hand side of the display
.The
function of these keys changes depending on the menu you are in.
x

1
Getting Acquainted with the HP 8530A Receiver
Chapter Contents
Product Description
Receiver Performance
Measurement Features
Input/Output Features
Principles of Operation
Front Panel Overview
Getting Acquainted with the HP 8530A Receiver 1-1

Product Description
The HP 8530A is a high-performance receiver that has been designed specically for antenna
and radar cross section (RCS) measurements.
The HP 8530A allows you to make angle-scan and frequency-scan measurements of antennas,
or make RCS measurements using the time domain feature.
Very fast measurement speeds are possible with the HP 8530A. By using a computer controller,
the receiver can measure up to 5,000 data points per second.
The receiver has very high sensitivity and dynamic range. The HP 8530A provides a large
amount of measurement exibility, providing the features you need for many dierent types of
measurements.
The HP 8530A must be used with a frequency down converter. The following HP down
converters are supported:
HP 8511A/B frequency converter
HP 85310A distributed frequency converter
HP 85325 millimeter wave subsystems (the HP 85325A and HP 85309A, used together, make
a complete frequency converter system).
These products down-convert microwave (or millimeter) signals to 20 MHz test and reference
signals that are measured by the HP 8530A. Figure 1-1 shows the basic block diagram of an
antenna measurement system.
1-2 Getting Acquainted with the HP 8530A Receiver

Figure 1-1. Basic Antenna Measurement Block Diagram
Receiver Performance
The most important feature of the HP 8530A is the accuracy and speed with which it makes
measurements. The important performance features are:
Excellent sensitivity.
Excellent linearity over a wide dynamic range
.
High speed data acquisition capability
.
Sensitivity
The foundation of good system performance and high speed is sensitivity|the ability to
measure very small signals
. Excellent sensitivity is only possible in systems that have very low
noise. When used with the HP 85310A frequency converter, the HP 8530 can measure signals
of 0 113 dBm from 3 to 18 GHz, and 0 96 dBm from 18 to 26.5 GHz. Excellent sensitivity
improves the signal-to-noise ratio of your system, allowing you to measure smaller signals more
quickly
,and with greater accuracy
.
Getting Acquainted with the HP 8530A Receiver 1-3

Linearity over a Wide Dynamic Range
Accuracy errors can occur when the power from the test antenna varies in signal level. For
example, assume that a test antenna has a bore-sight measurement of 0 dBi ( 0 20 dBm) and an
o-axis null of 0 50 dBi ( 0 70 dBm). This is a dierence of 50 dB. The HP 8530A receiver has
0.03 dB of error in this case. Even with a 60 dB dierence the HP 8530A has less than 0.04 dB
of error due to linearity. This specication is called \dynamic accuracy."
Fast Measurement Speed
The HP 8530 can measure 5000 points per second. As mentioned earlier, averaging slows
measurement speed. Because of the HP 8530A's excellent performance, you will need less
averaging, and can make faster measurements, than you would when using a receiver with less
performance.
High speed measurements are performed using the \Fast CW" mode, and must be done through
computer control.
1-4 Getting Acquainted with the HP 8530A Receiver

Measurement Features
The major operational features of the HP 8530A are listed below:
Angle Domain
Allows you to make angle scan measurements at a single frequency. In Angle Domain mode,
the x-axis of the display is angular degrees.You can measure a single angle, or a range of
angles. If you DO NOT have an HP 85370A Position Encoder, use external triggering (HP-IB or
TTL) in this mode. If you use the HP 85370A Position Encoder, use internal triggering mode.
Figure 1-2. Angle Domain
Frequency Domain
Allows you to measure antenna magnitude and phase performance across one or more
frequencies
.Frequency Domain measurements must be made at asingle
angle
.In Frequency
Domain mode
,the x-axis of the display is frequency
.Internal triggering is commonly used
when measuring frequency
,but external triggering can be used as well. Y
ou can measure a
single frequency
,or choose from Ramp
,Step or Frequency List sweep modes
.
Figure 1-3. Frequency Domain
Getting Acquainted with the HP 8530A Receiver 1-5

Time Domain
This optional feature allows you to make RCS measurements or see the time response of an
antenna (time is shown on the displays x-axis). One use of time domain is when measuring
multi-path range reections. Internal triggering is usually used in this mode.
Time domain data is mathematically calculated from Frequency Domain data. This is done
using the \chirp-Z" inverse Fourier transform. Therefore, the rst step in time domain
measurements is to make a measurement in the Frequency Domain.
Figure 1-4. Time Domain
Calibration
Antenna calibration provides accurate gain and frequency response measurements by
calibrating your range against astandard gain antenna. Also
,the isolation calibration feature
reduces measurement errors caused by signal crosstalk.
A\network analyzer" calibration is also provided. This calibration is used if you want to
make network analyzer-type measurements
.F
or example
,assume you want to measure
the impedance of an antenna input (or output). Y
ou would perform the network analyzer
calibration so you could make very accurate measurements. In this example a directional
coupler is required to measure the reected signals.
Four Measurement Inputs
The receiver has four inputs for receiving signals (a1, a2, b1 and b2). You must input a
reference signal into a1 or a2. Then, any other inputs can be used as test signal inputs.For
example
,assume you input the reference signal into a1. Y
ou could then use a2, b1, or b2 to
carry test signals. The \P
ARAM" keys
,described below
,select which inputs to ratio together
for your measurement.
Selectable Input Ratios
4
PARAM 1
5
, 4
PARAM 2
5
, 4
PARAM 3
5
, and 4
PARAM 4
5
, select a specic pair of inputs to ratio and
measure. (\PARAM" is short for \parameter
.") F
or example
, 4
PARAM 1
5 mathematically divides
(ratios) input b1 data by a1 data. You can redene the PARAM keys so they ratio any two
inputs you desire.You can also measure a single input without ratioing.
1-6 Getting Acquainted with the HP 8530A Receiver

Flexible Triggering
The HP 8530A provides three ways of triggering measurements:
Internal When in Internal trigger mode, the receiver does not require any
external or HP-IB triggering. This is useful when making frequency
measurements, or when using the HP 85370A Position Encoder.
External Triggering Allows you to trigger measurements using a TTL increment signal
produced by a positioner controller. This allows the receiver to take data
when the positioner is aligned with each measurement angle.
HP-IB Triggering Allows a computer to trigger a measurement by issuing a GET command
over the HP-IB bus.
Save/Recall Registers
The receiver has eight Save/Recall registers. Each can save current measurement settings for
instant recall at a later time. Register 8 is the \User Preset" register. Settings saved under
register 8 become active whenever you turn the receiver ON, or when you press 4
USER PRESET
5 .
Measure P
erformance Relative to the P
eak of the Main Lobe
The Normalize Trace function sets the peak of the main lobe (the data point of highest
amplitude) to 0dB
.Y
ou can then use markers to view trace magnitude values relative to this
reference point. When data is saved, printed, plotted, or output to computer
,magnitude values
will be relative to the peak.
Remote Programming
The HP 8530A can be controlled remotely from any computer that can communicate using
HP-IB
.All front panel features are supported. Y
ou can query the analyzer to determine current
modes of operation and current instrument or system status
.
Data Presentation Features
The HP 8530A can show measurement results right on its display
.It can display:
Antenna patterns
Frequency response measurements
Time domain
Radar Cross Section (RCS) frequency and time domain measurements
The HP 8530A allows you to print or plot measurement results
.
Display F
ormats
You can select logarithmic or linear magnitude display formats (Cartesian or polar), or phase
display format (Cartesian only). Y
ou can display one,two, or four parameters simultaneously on
the screen.
Multiple Measurements Can be Shown Simultaneously
The HP 8530A allows you to view up to four parameters at once, in split or overlay
presentation. Alternatively
,you can display one parameter from each of the independent
measurement channels (more on channels is explained later).
Getting Acquainted with the HP 8530A Receiver 1-7

Trace Memory and Trace Math
The trace memory feature is similar to the storage feature in a storage oscilloscope.You can
store the current data trace to memory, then compare it to subsequent measurement traces.
Trace math features allow you to perform vector addition, subtraction, multiplication, and
division. These operations are performed using the current data trace and the memory trace.
Each parameter has independent trace memory/math operation. In addition, trace math in
Channel 1 is independent from trace math in Channel 2.
Markers Display Precise Values for Any Point on display Traces
Five measurement markers give detailed information about any point on the measurement
trace. Delta markers allow you to show the dierence in amplitude, phase, angle,ortime
between any two points on the screen.
External Video Monitor
The HP 8530A can display results on an external multisync monitor. Refer to Appendix B for
details.
Optional Network Analysis
Option 011 adds high-performance vector network analysis features (HP 8510C operation).
This allows you to measure the transmission and reection properties of microwave devices in
frequency or optional time domains
.These advanced calibration features provide optimum
accuracy in S-P
arameter network measurements
.
1-8 Getting Acquainted with the HP 8530A Receiver

Input/Output Features
The HP 8530A can control other instruments, and has many input/output capabilities using
HP-IB, System Bus, RS-232, external monitor interface, and TTL BNCs.
Printing and Plotting Features
The HP 8530A can output data to a wide range of HP-IB or RS-232 printers or plotters. Laser
printers are also supported.
Many Supported Peripherals
The HP 8530A can control RF and LO signal sources, frequency converters, and large external
display monitors. Refer to Appendix B for details.
Built In Disc Drive
The built in disc drive allows you to save measurement data, data from memory, instrument
conguration setups, save/recall registers, calibration data, or user-created graphics. Both
DOS and LIF disc formats are supported, and both disc types are automatically recognized.
DOS format is compatible with MS-DOS
R

based computers
,such as IBM PCs and compatibles
.
LIF format is compatible with Hewlett-P
ackard computers
,such as the HP 9000 Series 300
workstation family
.
Getting Acquainted with the HP 8530A Receiver 1-9

Principles of Operation
This information is provided so you can have a better understanding of how the HP 8530A
makes measurements. If desired, you can skip this section and come back to it when
convenient.
Description of the HP 8530A
A simplied block diagram of the HP 8530A receiver is shown in Figure 1-5. It is a high
performance vector receiver with four inputs, two independent digital processing channels,and
an internal microcomputer that controls measurement, digital processing, and input/output
operations. Examples of \digital processing" are features such as averaging, time domain,
calibration, and so on. A special System Bus gives the receiver complete control over the
RF source and, if required, LO source. This interface allows the receiver to make hard copy
outputs to HP-IB compatible printers or plotters. Two RS-232 ports are also supplied for
printing or plotting.
The system must contain a frequency converter, which down converts the RF measurement
frequencies to a 20 MHz IF. The HP 8530A requires this frequency for its inputs.To create
the IF frequency, the HP 8511A/B frequency converter uses a built-in local oscillator. The
built-in LO is digitally tuned by the HP 8530A. This digital tuning data is sent over the \T
est
Set Interconnect" that links the HP 8530A and the HP 8511A/B. The local oscillator mixes the
measurement signals with asimilar frequency that is oset by 20 MHz. The result is the 20
MHz IF signal. Other down converters
,such as the HP 85310A, require another source to
supply an LO signal. The HP 8530A tunes external LO sources with HP-IB commands sent over
the System Bus
.
1-10 Getting Acquainted with the HP 8530A Receiver