Agilent Signal Studio for Enhanced Multitone

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1 Agilent Signal Studio for Enhanced Multitone Option 408 Technical Overview Construct Multitone Test Signals is a powerful tool for creating multitone I/Q waveforms. The software provides many flexible features to simplify the generation of in-band and out-of-band nonlinear distortion test signals. Custom tone patterns, initial phase relationships, and relative tone power can all be easily configured with the straightforward graphical user interface or with your own test executive using the built-in COM-based application programming interface (API). The software uses a pre-distortion algorithm to provide up to 1024 tones virtually free of IMD products from a single signal generator. The improved signal quality significantly reduces test uncertainty and capital equipment costs as compared to the traditional analog technique of summing multiple CW signal generators to create a multitone test stimulus. This software works with the Agilent E8267D PSG, E8267C PSG, and E4438C ESG vector signal generators. To perform the pre-distortion algorithm, PSA Series spectrum analyzer is also required. Features and Benefits Simplify the test setup and reduce capital equipment costs Easily navigate the intuitive, PCbased user interface to configure multitone test signals Apply pre-distortion to improve signal quality and minimize test uncertainty Correct IMD over 80 MHz bandwidth Suppress IMD (> 70 dbc), images, and carrier feedthrough Improve RF flatness Quickly download/playback signals over LAN and GPIB View peak-to-average statistics by plotting the CCDF curve Automate signal configuration and generation using the COM-based API Leverage programming examples in Visual Basic and LabVIEW Use built-in Help with multitone configuration examples Try Before You Buy Go to and download the Signal Studio for enhanced multitone software to your PC. The signal configuration and plotting capabilities of the software can be evaluated by navigating the user interface prior to purchase. To generate the configured signals, a license key is required to load the baseband waveforms created by the software into the vector signal generator for playback. The license key can be ordered through your sales engineer or the nearest sales office, which can be found at

2 Setup to Generate Distortion Free Multitone Test Signals LAN/GPIB bus E8267D PSG, E8267C PSG, or E4438C ESG vector signal generator PSA Series spectrum analyzers Example two-tone test stimulus with over 80 db 3 rd order intermodulation distortion (IMD) suppression 2

3 Reduce Time and Cost of Test Simplified test setup Vector modulation saves time and reduces capital equipment costs as compared to traditional analog techniques to generate multitone test signals. Instead of buying multiple signal generators for nonlinear distortion testing, or specialized multitone sources for amplifier testing, now you can use a single general-purpose signal generator to create all your RF and microwave test signals. Vector signal generators employ complex modulation to deliver an accurate and repeatable multitone test signal that can easily be configured to perform a variety of nonlinear distortion measurements. Rather than making hardware modifications to your test setup to change the stimulus characteristics, different multitone waveforms (with up to 1024 tones) are created mathematically using the Signal Studio for enhanced multitone software. Changing the test stimulus characteristics is now reduced to a few mouse clicks, which ultimately reduces the time and cost of test. Easily configure multitone test signals To configure a multitone test stimulus, use the PC-based graphical interface or API to set the characteristics of each tone independently with digital accuracy, including: enable/disable 2 to 1024 tones place tones within 80 MHz modulation bandwidth and set the relative tone spacing set relative tone power from 0 to 50 db choose from random, parabolic and constant phase distributions and/or independently set each initial tone phase directly As signal parameters are modified, spectral plots of the tone pattern and the complementary cumulative distribution function (CCDF) curve are automatically updated. This allows you to visually verify the configured signal and view the peak-to-average characteristics of the composite test signal as the signal is being built. Quickly download/playback test signals Once configured, I/Q waveforms are calculated by the software and downloaded to the vector signal generator over the LAN or GPIB interface. Connection to the instrument is easily established through the software. The waveforms are then fed to the I/Q modulator and the desired multitone test stimulus is upconverted to the signal generator carrier frequency. Waveform configuration and playback is fully controlled from the software user interface or programmatically. Even frequency and amplitude of the signal generator are conveniently set in the software and automatically updated with the waveform download. Once downloaded, pre-distortion algorithms can be applied to improve the signal quality. 3

4 Reduce Test Uncertainty Signal Studio for Enhanced Multitone Before correction algorithm......after correction algorithm Distortion correction LAN/GPIB E8267D PSG, E8267C PSG, or E4438C ESG PSA series Improve signal quality significantly improves the IMD suppression, RF flatness, image suppression, and carrier feed through performance of multitone test signals generated by the PSG and ESG vector signal generators. The improved signal quality is achieved by applying pre-distortion to the I/Q waveform based on an iterative correction algorithm. The phase and amplitude relationships between the tones are known, and can be stored as part of the configuration, so your test pattern is predictable and repeatable from device to device. Configure and calibrate the multitone waveform using the Signal Studio graphical interface or use the API to control the process with your own test executive. Once initiated, the software takes control of the signal generator and spectrum analyzer to make measurements on the IMD created by the signal generator while it plays back the multitone I/Q waveform. Based on these measurements, the software calculates and downloads a new pre-distorted waveform to cancel the IMD created by the signal generator. The Signal Studio software automates the entire process, so that distortion-free multitone signals can quickly and easily be realized with minimal user intervention. Once the system is calibrated, the spectrum analyzer is available for other measurements. Calibration lasts approximately 8 to 10 hours and the setup is repeatable. 4

5 Minimize IMD caused by additional devices in the test setup The software also removes distortion caused by additional devices (such as power amplifiers) inserted between the signal generator and the DUT. Signal Studio s innovative correction routine enables the generation of distortion free, repeatable multitone test signals directly at the input of the DUT. If using external power amplifiers or filters, simply enter the path gain/loss respectively and the correction routine adjusts accordingly. Corrections can even be initiated at offset frequencies to account for frequency shifting devices, such as upconverters, in the test setup. Once inserted into the calibrated test loop, the DUT s non-linear distortion products can be measured with minimal uncertainty. Automate the Test Process Use the COM-based applicationprogramming interface to generate multitone waveforms directly from your test executive rather than the graphical user interface. The entire signal configuration and playback process can be automated in your own programming environment. Visual Basic and LabVIEW programming examples are provided in the software s built-in Help system. These programming examples can be easily leveraged to minimize the programming and automation learning curve. Remove IMD caused by additional devices Reduce measurement uncertainty by minimizing test stimulus IMD... even at the output of an external power amplifier. LAN/GPIB Distortion correction Step 1 Correct to produce a low IMD test stimulus External AMP E8267D PSG, E8267C PSG, or E4438C ESG 1 2 Step 2 After correction, insert DUT and measure nonlinear distortion products PSA Series DUT 1 2 5

6 Signal Studio for Enhanced Multitone Features 1, 2 Number of tones 2 to 1024 Tone spacing 1 khz to 50 MHz, limited by 80 MHz I/Q bandwidth. Spacing is linear, however individual tones may be disabled. Tone power (relative) 0 to 50 db Phase distribution Fixed, random or parabolic Suppression bands Set up to 10 different suppression levels over different band segments Suppression level 3 50 to 90 dbc, depending on number of tones and available calibration time. Calibration interval 8 hours (recommended) Calibration time (typical) 10 minutes ( 8 tones, 80 dbc suppression) 3 Temperature stability ESG 1 db/ C (typical for IMD products) 5 db/ C (worst case for LO feedthrough and images) (See typical performance plot below) PSG 3 db/ C (typical for IMD products) 5 db/ C (worst case for LO feedthrough and images) Amplitude accuracy ±.2 db (typical) 4 Connections 10baseT LAN or IEEE-488 GPIB Instrument settings ESG/PSG Frequency, amplitude, markers PSA Span, RBW, VBW, attenuator setting, detector type, number of averages, trigger source Graphic displays Tone settings and suppression bands, CCDF Application programming COM object interface Even symmetry test case 8 tones, 3 MHz spacing Average amplitudes of LO and IMD products relative to carrier amplitude Upper suppression limits of enhanced multi-tone signal studio Amplitude relative to carrier (dbc) Frequency offset (MHz) Suppression level (db) Number of tones = 5* Number of tones = 16** Number of tones = 32*** Frequency (GHz) * 5 tones, 5 MHz tone spacing, 0 dbm RF power, corrected across 80 MHz span. ** 16 tones trend extrapolated from 5 tone and 32 tone data. *** 32 tones, 1MHz tone spacing, 0 dbm RF power, corrected across 80 MHz span. 1. Subject to change. 2. For best performance, use an odd number of tones symmetrically placed around center frequency in a stable temperature environment. 3. Spectrum analyzer averaging set to four. 4. With amplitude accuracy adjustment enabled. 6

7 Ordering Information is Option 408 for both the E8267D PSG, E8267C PSG or E4438C ESG vector signal generators. To take full advantage of the software, the following signal generator configurations are recommended: E8267D PSG recommended configuration Option number Description E8267D-520, 532, or 544* E8267D-602** E8267D-005 E8267D-UNR E8267D-408** 250 khz to 20 GHz, 31.8 GHz or 44 GHZ frequency range Internal baseband generator, 64 MSa memory 6 GB internal hard drive Enhanced phase noise performance E8267C PSG recommended configuration Option number Description E8267C-520** E8267C-602** E8267C-005 E8267C-UNR E8267C-408** 250 khz to 20 GHz frequency range Internal baseband generator, 64 MSa memory 6 GB internal hard drive Enhanced phase noise performance E4438C ESG recommended configuration Option number Description E4438C-501, 502, 503, 504, or 506* E4438C-602** E4438C-005 E4438C-UNJ E4438C-408** 250 khz to 1, 2, 3, 4, 6 GHz frequency range Internal baseband generator, 64 MSa memory 6 GB internal hard drive Enhanced phase noise * One of these three options is required. ** The baseband generator requires one of the following options: For the E8267D: E8267D-601, or 602 For the E8267C: E8267C-002, or 602 For the E4438C: E4438C-001, 002, 601, or 602 To perform signal corrections, an Agilent PSA Series spectrum analyzer is also required. A variety of demodulation personalities are also available for the PSA. For additional information, refer to the PSA configuration guide. Upgrade kits If you currently own an E8267D PSG, E8267C PSG, or E4438C ESG vector signal generator and are interested in obtaining a software upgrade kit (license key), order option: E8267DK-408, E8267CK-408, or E4438CK-408. Other configurations are available. For additional information, refer to the ESG and PSG vector signal generator configuration guides. 7

8 Related Literature Agilent E8267D PSG Vector Signal Generator, Data Sheet, literature number EN Agilent E8267D PSG Vector Signal Generator, Configuration Guide, literature number EN Agilent PSG Signal Generators, Brochure, Literature number EN Agilent E8267C PSG Vector Signal Generator, Data Sheet, Literature number EN Agilent PSG Vector Signal Generator Self Guided Demo, Literature number EN Agilent E8267C PSG Vector Signal Generator, Configuration Guide, Literature number EN Agilent PSG Two-tone and Multitone, Application Note AN 1410, Literature number EN Agilent E4438C ESG Vector Signal Generator, Brochure, Literature number EN Agilent E4438C ESG Vector Signal Generator, Data Sheet, Literature number EN Agilent E4438C ESG Vector Signal Generator, Configuration Guide, Literature number EN Characterizing Digital Modulated Signals with CCDF Curves, Application Note, Literature number E Agilent PSA Series Spectrum Analyzers, Brochure, Literature number E Agilent PSA Series Spectrum Analyzers, Data Sheet, Literature number E Agilent Technologies Test and Measurement Support, Services, and Assistance Agilent Technologies aims to maximize the value you receive, while minimizing your risk and problems. We strive to ensure that you get the test and measurement capabilities you paid for and obtain the support you need. Our extensive support resources and services can help you choose the right Agilent products for your applications and apply them successfully. Every instrument and system we sell has a global warranty. Support is available for at least five years beyond the production life of the product. Two concepts underlie Agilent s overall support policy: Our Promise and Your Advantage. Our Promise Our Promise means your Agilent test and measurement equipment will meet its advertised performance and functionality. When you are choosing new equipment, we will help you with product information, including realistic performance specifications and practical recommendations from experienced test engineers. When you receive your new Agilent equipment, we can help verify that it works properly and help with initial product operation. Your Advantage Your Advantage means that Agilent offers a wide range of additional expert test and measurement services, which you can purchase according to your unique technical and business needs. Solve problems efficiently and gain a competitive edge by contracting with us for calibration, extra-cost upgrades, out-of-warranty repairs, and onsite education and training, as well as design, system integration, project management, and other professional engineering services. Experienced Agilent engineers and technicians worldwide can help you maximize your productivity, optimize the return on investment of your Agilent instruments and systems, and obtain dependable measurement accuracy for the life of those products. Agilent T&M Software and Connectivity Agilent s Test and Measurement software and connectivity products, solutions and developer network allows you to take time out of connecting your instruments to your computer with tools based on PC standards, so you can focus on your tasks, not on your connections. Visit for more information. For more information on Agilent Technologies products, applications or services, please contact your local Agilent office. The complete list is available at: Product specifications and descriptions in this document subject to change without notice. Phone or Fax Optimizing Dynamic Range for Distortion Measurements, Application Note, Literature number EN Web addresses See for more information United States: (tel) (fax) Canada: (tel) (fax) China: (tel) (fax) Europe: (tel) Japan: (tel) (81) (fax) (81) Korea: (tel) (080) (fax) (080) Latin America: (tel) (305) Taiwan: (tel) (fax) Other Asia Pacific Countries: (tel) (65) (fax) (65) tm_ap@agilent.com Contacts revised: 9/17/04 Agilent Updates Agilent Technologies, Inc. 2003, 2004 Printed in USA, October 28, EN Get the latest information on the products and applications you select.