1140B and 1141B VXIbus Synthesized Signal Generator:
The 1140B and 1141B are ideal for classical ATS and SI applications. The 114XB family of synthesizers occupy only three VXI slots yet cover the entire 0.01 to 20 GHz frequency range, depending on the model chosen (see datasheets for more information). All models feature a complex modulation capability and outstanding spectral purity. The complex modulation capability is implemented via an intermediate frequency (IF) input port, which has the capability (when used in tandem with an ARB/DAC) to up convert and modulate the synthesizer's RF carrier frequency into a complex signal that may be used to emulate various threat scenarios. All of the 114XB variants are fully compliant with revision 1.3/1.4 of the VXI bus specification for message-based instruments and with the Standard Commands for Programmable Instruments (SCPI) version 1993.

1313B VXIbus Microwave Downconverter
The 1313B translates microwave signals IF with minimal distortion. The 1313B is a modular VXI-based, broadband down converter (1 MHz-26.5 GHz) optimized for SI applications. The 1313B provides the user with basic microwave front-end-signal-conditioning building blocks to extend VXIbus signal analysis into the microwave range. In conjunction with the Phase Matrix's 20309 VXIbus Local Oscillator module and commercially available digitizers and application software, this single-slot down converter solution can provide the functionality of several stand-alone instruments (i.e., spectral analysis, power measurement, frequency measurement, modulation analysis, and pulse-parameter analysis.)

20309 VXIbus Local Oscillator
The 20309 is a combination of compact, synthesized-signal sources optimized for use in classical down-converter and SI applications. In only one (1) C-size, VXI slot, the 20309 combines a 3-9GHz main LO, as well as additional lower, frequency-synthesized sources. The 20309 is a complete LO solution whether you are using single- or multiple-stage down conversion. The 20309 is a companion module used in tandem with the 1313B VXIbus Microwave Downconverter and is fully compliant with VXIbus specification 1.3/1.4 for register-based instruments.

Our SI products have supported the Air Force’s F16 Improved Avionics Intermediate Shop (IAIS), the Marine Corps Viper/T, and the Air Force’s F15 ESTS test systems.

While well accepted in the DOD/Mil marketplace, SI is not as well understood and is still an emerging technology in the commercial test and measurement (T&M) marketplace. Our interactions with commercial customers in joint efforts to produce proof-of-concept demos with National Instruments has indicated a strong interest in the SI paradigm of employing a core set of hardware components (i.e., up converter synthesizers, down converters, local oscillators, digitizers, and computational hardware) and personalizing the measurement in software such as LabVIEW and LabWindows/CVI). Commercial customers are motivated primarily by the reduced test-system footprint and mitigation of test system obsolescence. The ability to develop and procure just-in-time measurement software (i.e., Spectrum Analysis and Network Analysis), utilizing LabVIEW or LabWindows/CVI is also an added incentive for commercial users to employ SI.

For more information, see our paper, "SI-Based Applications: Commercial Test Systems CTS)", which describes three PC-based power applications (hybrid VXI/PXI network analysis, LXI/VXI spectrum analysis, and hybrid VXI/PXI frequency counting). The hybrid VXI/PXI applications were a collaborative effort between National Instruments and Phase Matrix and were demonstrated at NI Week 2007 and Autotestcon 2007.

The hybrid VXI/PXI spectrum-analysis system leverages the best in class of core PXI/VXI assets to synthesize a highly compact and capable SI test system, operating up to 6.6GHz. The system can be extended up to 20 GHz by adding Phase Matrix's 1140B VXIbus Synthesized Signal Generator to the system. On the PXI side, the system employs an NI PXI 5652 RF source (500KHz-6.6 GHz) and a NI 51242 MS/s /12 bit digitizer. The RF source uses direct digital synthesis (DDS) for high-resolution frequency hopping or phase continuous sweeping. On the VXI side, the system employs Phase Matrix`s 1313B VXIbus Microwave Downconverter (1 MHz-26.5 GHz) and companion 20309 VXIbus Local Oscillator (3 to 9GHz) controlled by a NI USB controller card. The VXI assets are packaged in a highly compact four (4) slot VXI chassis.

The DOD Synthetic Instrument Working Group (SIWG) is identifying a core set of specifications for designing and characterizing future SI components such as down converters, up converters, and digitizers. The recently approved SIWG Down Converter Definition Document Rev 2.2a identifies “best specification practices” such as absolute group delay and phase deviation from linear (phase linearity), associated with testing, in an SI context, high-bandwidth digital communication systems. Also, it is anticipated that the upcoming Navy eCASS test equipment procurement will require consideration of SI in any proposed solution architectures.

Currently, our SI components are C-size, VXI-based. We are working with BAE Systems and National Instruments on a PXI (3U) based test system, which will provide a turnkey measurement capability up to 26.5 GHz. Phase Matrix will be providing the down converter portion of this solution, which is being developed under a Phase II SBIR (Small Business Innovative Research) contract with the Department of Defense (Navy). Look for a beta version of this system in Q3/Q4 of CY2008.

No, we have determined that PXI and PXIe specifications and associated architectures provide the most appropriate size, modularity, and bus bandwidth attributes to field best-in-class SI test solutions to support cutting-edge devices under test (such as software defined radios). However, for those who require the LXI form factor, please contact National Instruments (NI) about incorporation of the Phase Matrix family of downconverters in LXI and PXI synthetic hybrid systems.

All of our VXI-based SI products can be best described as "building-block" components from which stimulus hardware emulator (SHE) and measurement hardware emulator (MHE) subsystems or systems can be synthesized with COTS software such as LabVIEW as the measurement engine.

All of our VXI-based SI products are generic SI-building blocks (components) that can be re-programmed or reconfigured in response to a particular SI test application. For example, using LabVIEW, the user can instantiate a spectrum/signal analyzer measurement routine to operate on sampled test data in one test and then can call upon a time-based measurement routine (i.e., time interval) in the next test. In both of these scenarios, the hardware (down converter/LO) can be reconfigured (i.e., frequency span/band) to accommodate the special frequency translation needs of the software-based test algorithm.

Our VXI components have been used with both factory-provided and user-created test patterns. For example, our VXI 1140B Upconverter/Synthesizer can take user provided I/Q modulation signals or complex stimulus patterns from a user-provided ARB/Function generator and up convert that stimulus into the RF/MW domain up to 20 GHz for use in emulating various microwave signal threat scenarios.

Our VXI-based SI building blocks (components) can interact with various industry standard I/Os with the appropriate converter card (i.e., LXI/VXI, GPIB/VXI) inserted in slot 0 of a VXI chassis. With respect to PXI interfacing, our VXI-based SI building blocks can be remotely controlled by PXI-based VXI controllers such as the National Instruments VXI-PXI 1801x, which links a PXI system directly to a VXIbus using the high speed MXI-2 bus. Our emerging PXI product line will function in both PXI and PXIe controlled test systems.

VXI- and PXI-based SI provides a smaller footprint, mitigates ATS obsolescence (from a hardware perspective), and provides system flexibility via instantiating stimulus and measurement functions in software utilizing core/generic hardware components and not instrument specific hardware and firmware.

SI employs a signal-based paradigm and as such can be made to emulate or perform stimulus and response functions similar to traditional instruments. Our SI building blocks (components) that are integrated into an SI system with the appropriate stimulus and measurement test application software and hardware digitizer are capable of emulating and replacing the vast majority of traditional test instrumentation.

#1 Reduced Footprint
Depending upon the customer's test requirements and the nature of the devices under test, the impact of SI on footprint can be significant. For example, if a signal-based application is implemented in VXI or PXI and the appropriate SI functions (i.e., spectrum analysis, network analysis, and waveform analysis) are provided in application software, a multi-rack system can be reduced to a rack or less of SI, including instrument-specific hardware for those functions not easily implemented in SI. However, if a test station is dedicated to high-power or load testing, the affect on footprint will be minimal.

#2 Reduced Purchase Cost
SI can reduce purchase cost, which is again dependent on the customer's test requirements and includes both hardware and test application software costs. From a hardware perspective, the non-recurring cost for a 26.5GHz VXI SI system that uses both state-of-the-art stimulus and measurement hardware emulation capability should be in the $50 to 100K range. The capabilities should include a full modulation (i.e., AM, FM, Pulse, and I/Q) capability on the stimulus side. On the measurement side, spectrum analysis, signal/modulation analysis, digital scope/time domain analysis, frequency counter, and power meter capabilities should also be provided supplemented via COTS software such as LabVIEW or LabWindows /CVI.

#3 Reduced Calibration Cost
Calibration cost should be included in the non-recurring cost of an SI system. A calibration source should be provided by the system integrator. Phase Matrix provides calibration data for all its SI components.

#4 Improved Reliability
By the very nature of providing a generic and or application-specific T&M capability that utilizes a core-reduced hardware set of components (i.e., up converter; down converter; digitizer; arbitrary waveform generator, D/A; and I/O) and measurements implemented in software, SI will invariably lead to improved hardware reliability over traditional rack-and-stack systems that employ classical instruments dedicated to specific measurement functions (i.e., spectrum analysis, oscilloscope, counter, and network analysis).

#5 Improved Speed of Test
In many instances, SI improves test speed, especially for SIs that employ high-speed I/O such as PCI/PXI Express, which results in high test system throughput. In some cases, data capture using analog techniques may be faster due to the high number of data samples that an SI system must take to effect an accurate measurement. This anomaly is offset somewhat by the fact that an SI may generate many measurements from a single data capture employing SI sampling techniques.

#6 Other Benefits
Benefits of using SI include higher data throughput, reduced footprint, open architecture, reduced training costs (do not have to provide training on a multitude of unique instruments), and relative ease of upgrading. Also, a big advantage of the SI paradigm is user flexibility in that it helps mitigate test plan uncertainty. That is, if the user does not specifically know all of the test requirements or emerging test requirements, he or she may instantiate just-in-time tests, employing the generic test hardware and test platform software (i.e., LabVIEW) provided with his system. No need to worry about adding specific COTS or custom instrumentation to affect latent or emerging test requirements.

SI software can be made to emulate—but not exactly duplicate—tests that were previously implemented on legacy ATS instruments. This is predicated on the SI supplier or SI system integrator's ability to emulate legacy T&M application tests using the SI software system of choice (LabVIEW, LabWindows/CVI, C, and C++). In many instances, legacy tests can be replicated with minor adjustment of legacy test system limits.

Yes, two well-documented instances exist:

1. F-16 R-IAIS:
As part of the F-16 R-IAIS program, 31 TPSs that were originally developed on the F-16 M-IAIS have been re-hosted onto the R-IAIS, using an RF SI. The original M-IAIS RF section utilizes a BAE Systems designed microwave measurement and stimulus system consisting of 16 modules that are designed to test the RF and EW systems from the F-16. The re-hosted TPSs and all newly developed F-16 TPSs are transportable between the R-IAIS and M-IAIS and can run on both versions of the RF section. In addition, using RF SI technology and a subset of the IAIS, the ALQ-131 and ALQ-184 Electronic Attack Pod TPSs are being re-hosted from their original testers onto what is called the EA-IAIS.

2. Viper T/TETS
DME Corporation and the Marine Corps Systems Command's Viper-T/TETS program has also affected TPS transportability using SI. In fact, not only did the program implement transportability of legacy TPSs but also affected program enhancement and expandability from 8.5 GHz to 18 GHz with backward compatibility to the older TETS test system on the measurement as well as source side.

Yes, upgradeability is one of the basic premises of the SI paradigm. Hardware upgrades, for example, can take the form of higher sampling rate digitizers or arbitrary function generators (DACS). Upgrades to down converters and up converters can take the form of increasing or extending the frequency range of these components (i.e., 20 GHz to 40 GHz). Software upgrades can take the form of new (i.e. network analysis) or improved and quicker (i.e., FFTs) software algorithms.

Most of the upgrades in an SI system are software upgrades (i.e., added stimulus/measurement functionality or tweaking of algorithms to make tests run faster). Therefore, the cost of upgrades are significantly lower than the original purchase price, assuming the customer has adequately defined the baseline of the SI system's hardware and software requirements.

Downward compatibility is easier to ensure in the SI architecture than it is in rack-and-stack instruments because T&M measurement functions are based more in the PC-based software than in the instrument's firmware as is the case with classical instruments.

19. What software is used to control SI components?

Typically, LabVIEW, LabWindows/CVI, and C are software platforms employed by SI integrators.

Yes, we utilize NI LabVIEW and its associated toolkits (i.e., Modulation toolkit, Spectral Measurements Toolkit). Other pre-defined software routines are available in tools such as Matlab and MathCAD; algorithms from these tools may be made to be scripted and implemented within LabVIEW. Also, the NI website and its NI Zone landing page is an excellent source of information.

Yes, LabVIEW is very flexible and user friendly in this regard.

The user should have knowledge of test applications, measurement science, and collecting and presenting data.

23. What SI products will Phase Matrix be introducing in the future?

Phase Matrix is introducing a developmental model of its microwave-band input module. This core down converter module is capable of down converting RF and MW signals in the 2.7 to 26.5 GHz range into base band IF signals of 21.4 MHz (50 KHz and 8 MHz BW) or 250 MHz (+/-175MHz min.). This module is the first of a series of five modules intended for dual use (i.e., for military and commercial applications). The entire family of modules incudes the following:

1. Low-Band Input Module (DC-2.9 GHz)
2. RF Input Signal Conditioning Module
3. IF Output Conditioning Module
4. Local Oscillator Module
5. Microwave Band Input Module (MBIM) (2.7-26.5 GHz)

Five:

Configuration #1: DC-2.9 GHZ (no pre-selection)
Configuration #2: 2.7-26.5 GHz (no pre-selection)
Configuration #3: 2.7-26.5 GHz (pre-selection)
Configuration #4: DC-26.5 GHz (pre-selection, 2 IFs, and 2 Digitizers)
Configuration #5: DC- Millimeter (mm) (pre-selection, 2IFs, and 2 Digitizers)

Rigorous beta-testing has yielded valuable design improvement information, which is currently being incorporated into the final COTS production units, resulting in availability for order in Q2 of CY 2009.

We are currently in the product definition phase for a Stimulus Hardware Emulation (SHE) capability, which will encompass both a CW stimulus and modulation capability up to 20 GHz.

We will provide calibration data for each down converter module. System-level calibration (including the digitizer) will be provided by the system integrator (BAE) or the end user. Phase Matrix will provide a generic methodology for the user to follow in order to properly calibrate the target down converter system configuration. We will provide a system-level driver with each down converter hardware module set that will properly align the down converter sub-system prior to system calibration. The down converter system driver will address any one of the five possible system configurations identified in FAQ #24.

The NI PXI 5122 (14bit, 100 MS/s), NI PXIe 5122 or NI PXI 5124 (12 bit, 200 MS/sec) in support of narrow Band IFs (CF=21.4 MHz IF), and the NI PXI 5152 (8bit, 2 GS/s) in support of wideband IF outputs (CF=250 MHz).

The LabVIEW Development System, NI Modulation Toolkit for LabVIEW, and the Spectral Measurements Toolkit for Windows.

BAE is our preferred system integrator. Please contact Mr. Wade Lowdermilk at BAE Systems (email: wade.lowdermilk@baesystems.com, Tel: 1-858-675-2912). For general time and spectral frequency measurements that can be implemented utilizing NI`s LabVIEW, Spectral Analysis Toolkit, and Modulation Analysis toolkit, please call Mr. Mark Holtzer at National Instruments (email: mark.holtzer@ni.com, Tel: 301-258-1157) to discuss the software toolkits or for a listing of NI Alliance certified software developers.

Any RF or MW measurement application that requires the translation of a CW or modulated signal into a baseband (IF) environment for subsequent digitization and signal analysis and evaluation utilizing COTS tools such as NI`s LabVIEW, Modulation Analysis Tool Kit, and the Spectral Analysis Toolkit.

For technical information, you can contact Mike Granieri (email:mgranieri@phasematrix.com, Tel: 703-644-6015) or Mr. Pete Pragastis (email: ppragastis@phasematrix.com, Tel: 408-954-6400).

For sales information (i.e., beta-test units and production sales and delivery information), you can contact our sales team via email at sales@phasematrix.com or call PMI toll free @ 1-877-447-2736).