Nearfield Systems Inc. - Software


The NSI 2000 Software is the most advanced and comprehensive antenna measurement software available today. Running on a large number of installed systems and field-tested daily by an active community of experienced users, the NSI 2000 software represents a combination of experience and technology that stands ready to solve your toughest antenna measurement challenges. NSI 2000 is a 32-bit multi-tasking Windows application that runs under Microsoft Windows 95, 98, NT, 2000, XP and 7 and provides an excellent array of features that take advantage of the recent advances in operating system technologies including networking, OLE/DLL, scripting and web support.

NSI is continuously improving and updating our software to provide you with the tools you need. We recently developed and implemented a novel technique for suppression of range reflections which we call MARS (Mathematical Absorber Reflection Suppression). You can read more on the MARS capability here.

See NSI2000 Software FAQ for more information.

NSI 2000 includes a 3-D viewer that can be used to inspect near-field and far-field data in a 3-D dynamic mode, which can help you gain insights into an antennas performance. Note the individual amplitude and phase cuts vertically and horizontally through the 3-D data, which are selected by positioning the curser on the 3-D display. The Dynamic rotation and zoom features allow the plot to be easily manipulated through either mouse or keyboard control.

NSI is committed to supporting the latest versions of the Windows operating system, keeping your measurement system up-to-date. If you're already invested in the Microsoft Windows platform, then the NSI 2000 software will multiply your antenna measurement productivity while reducing your risk of obsolescence. NSI 2000 is available in two different editions: Standard and Professional. Each Edition provides various programming options. The Standard Edition has a wide variety of features and capabilities for both near-field and far-field antenna measurements. The Upgrade to Professional Edition includes a powerful scripting tool to automate nearly every function of NSI 2000. See some examples of NSI's scripts here. The scripts can also be assigned to NSI's macro toolbar for one-button access.

The NSI 2000 software is capable of controlling both near-field and far-field measurement systems. Additional details on NSI 2000 far-field software are discussed in our far-field section.

Features and Capabilities

The NSI 2000 software has features not found in any other commercially available software package. The ability to integrate customer written programs through the use of script commands and DLL links is a feature unique to our NSI-2000 Professional Edition. This is an important consideration for customer who may have proprietary algorithms to be used with the system or for those who may want to customize the software for their special applications.

NSI 2000 Software Features
  • Data collection and processing software integrated into a single package
  • Full 32-bit Windows application with support for standard Windows conventions (cut and paste, right mouse click for additional options, etc.)
  • Modular design provides direct support for near-field and far-field applications
  • Collection of arbitrary frequency, beam and switch combinations
  • Support for all major RF receivers, network analyzers and sources. Device drivers included with the base code allowing quick exchange of devices for calibration, repair or alternate use.
  • Position control using multiple controllers
  • Adjustment and control of measurement smear
  • Gain calibration and pattern measurements
  • Ability to export plot or measurement data to an ASCII file for customer analysis
  • Post-measurement analysis routines included (beampeak, beamwidth, side lobes level, etc.)
  • Drag and drop plot overlays
  • Operator controlled plot annotation
  • On-line help
NSI 2000 Standard Edition

NSI 2000 Standard Edition provides all the useful features our customers have come to know in our previous versions of software. Within the Standard Edition, you will find capabilities that only NSI can provide through our patented technology. The following is a list of features our Standard Edition provides :

Measurements Processing Hardware Compatibility Plotting
Planar near-field
Cylindrical near-field
Spherical near-field
Auto scan set-up
Continuous or stop motion
Bidirectional Scans
Drift Check
Multibeam, Multifrequency
measurements (depends on
RF equipment)

Near-field transforms:
Coordinate systems:
    K-space (Planar only)
    Theta-phi and others
Linear and Circular
polarization displayed.
Available polarization
definitions for planar
    Ludwig-3 (Eh, Ev)
    Ludwig-2 (Eaz/Eel)
    Ludwig-2 (Eel/Eaz)
    Ludwig-2 (Eq/Ef)
Hologram (Back projection)*
MTI compensation (optional
for Planar only))
Gain, Directivity
Analysis Beamwidth,
peak, side lobes levels
Probe Correction Models:
   Open-ended waveguide
Aperture truncation and
tapering (Planar only.)
Probe position compensation
K-Correction (Planar only.)

    All NSI Scanners
    Any stepper

    based scanner
    NSI Positioners
    GPIB control of      some 3rd
    party controllers
    Agilent 8530A
    Agilent 8753 D/E
    Agilent 8720 D/E
    Agilent 8722 D/E
    Agilent 8719 D/E
    Agilent PNA
    Agilent PNA-X

    Agilent ENA
    Panther 6000
    Panther 9000
NSI Hand-held remote

Antenna patterns of:
    Amplitude, Phase,
    Principal, Pol Cross-pol
Plot Types:
    Linear, polar, gray-scale,
    Contour, 3D plots, and
Windows 95/98/2000/NT/XP/7
    Copy to clipboard
    Print to any windows
    compatible printer
    ASCII listing to file
Plot Customization:
    Scales Comments
    Multiple on-screen plots
    Multiple plot overlays
Compatible File Formats:
    NSI 2000
    NSI 2000
    NSI 97
    NSI Lite
    NSI V3.5

NSI 2000 Standard Edition supports planar, cylindrical, and spherical as well as the following multi-tasking modes :

Run external programs like MS Word, Excel, or Internet browser
Use a second networked computer to process measured data
Process older NSI Lite, V3.5, and NSI 2000 data files
On-line Help

The extensive on-line help includes tutorials, detailed menu descriptions, and answers to frequently asked questions are accessible through our electronic documentation supplied with each system :


NSI 2000 supports a wide variety of plotting formats and output. In addition to plotting, NSI 2000 supports an ASCII file output that provides a simple and universal method of data exchange. The examples below show some of the plotting and output capabilities of the NSI 2000 software. Each plot can be used with the Windows clipboard for import into Word, Excel or Powerpoint.

Multi-beam data collection

The NSI 2000 beam table allows you to easily create and edit lists of measurements that can be taken in a single scan. These include the ability to take multi-frequency, multi-switch and multi-axis measurements. The example below shows a typical NSI 2000 beam table for a dual polarization scan. Note that the Beam SW and Frequencies are in no particular order. Completion of a scan represented by this beam table will result in a data file with sixteen (16) amplitude and phase near-field data sets representing each of the eight beams shown in the table with both principle and cross polarization data.

Post-measurement analysis

NSI 2000 includes post-measurement analysis functions that are produced as part of the standard output. The analysis output includes beamwidth at 3 dB, 6 dB and 10 dB levels and right and left side lobe levels. With the NSI 2000 Professional Edition, the script language can be used to produce plots with any level of sophistication. The analysis results can be easily placed into the plot text before printing.

Software Drivers

NSI 2000 supports all major RF receivers, network analyzers, and sources. The device drivers are resident in the base code allowing quick exchange of devices if desired (requires NSI software support contract and may require additional hardware in some cases). Supported devices include:

  • NSI Panther 6000 and 9000 high speed receivers with NSI, Agilent MXG, VXI, 8360 series, Comstron, or Gigatronics sources
  • Agilent N522x PNA and N524x PNA-X
  • Agilent N5264A PNA-X Receiver
  • Rohde & Schwarz ZVA
  • Agilent E836xB/C PNA
  • Agilent 8530A dual source with distributed frequency converter (NSI 85301B system)
  • Agilent 8530A, single source with 8511 frequency converter (NSI 85301C systems)
  • Rohde & Schwarz ZVC/ZVM/ZVK
  • Agilent 8753ES/ET VNA
  • Agilent 8722D/E VNA
  • Agilent 8720D/E VNA
  • Agilent 8719D/E VNA
  • Agilent ENA
NSI 2000 Professional Edition
Acquisition functions

On-the-fly position correction

Far-field transform setup
Probe pattern file correction
Hologram Back Projection
Planar surface hologram
Plot formats and options
Active Test Procedures
Scripting Tool

NSI 2000 Professional Edition includes a powerful scripting tool for making custom acquisition and processing scripts. These give the user complete and automated control of the NSI software. Scripts are constructed using the Script Construction Kit shown below. Within the script development environment, scripts can be easily created by drag-and-dropping script commands from the script command list on the left to the code window on the right. Built-in debug and graphical user interface utilities assist in the script development process. NSI's professional edition includes a number of very powerful scripts (link), which you can use or adapt as needed.

Scripts are written in a Basic language. They can include commands to control every operation you can do from the menu and dialog interfaces and provide access to NSI internal data arrays. In addition, scripts allow you to call your own processing functions or to control other equipment by calling routines in DLLs. This includes access to Windows API functions. Scripts can even have a graphical user interface!

Here are some of the things you can do with scripts :

  • Create button macros for test that are routinely performed.
  • Automatic acquisition and processing of a set of files
  • Parametric studies with plot overlays: FFT size, coordinate system, phase center, etc.
  • Custom modification of near-field data (amp, phase) prior to processing
  • User-defined calculations of antenna parameters
  • Custom probe motion to any position and receiver reading
  • Near-field data simulation
  • Send an email message to notify completion of a scan
  • Interface with other Active-X supported applications, such as Microsoft Word and Excel.
Active Test Procedure

One of the most exciting features offered with the NSI 2000 Professional Edition is the Active Test Procedure. This capability allows the user to create a Word document or Excel spreadsheet that can control an NSI 2000 measurement or processing task which can be used to help streamline data analysis and report generation. A sample Active Test Procedure might contain a table of near-field parameters and a button that sets up a test. The "Run test" button starts the acquisition, and the processing buttons will process the measured data and save the results in the document. The Active Test Procedure can be as simple as a one-button test or it can be written to do complex data manipulations and fill in a custom test report. All this can be done through the NSI scripting interface. Below is a sample result from an Active Test Procedure example that NSI provides to our customers

Control of External Devices Through NSI 2000

NSI 2000 can control external devices that are used to adjust the measurement path as in the case of an RF switch used to change polarization, or to control the state of an antenna, beam position or array element. External devices that are fast switching, such as RF PIN diode switches, can be controlled while NSI 2000 is acquiring data. Slower devices, or those with unpredictable switching times, require that the scanner be stopped before they can be changed. NSI 2000 supports external devices in two ways without modification to the program.

Via the Script Programming Language

A script can be created to call an external DLL that controls an external device, i.e. beam controller, via GPIB in order to set the device state. This type of control must be done after the positioner or scanner has stopped.

Via Open-loop Control

If the device can respond to a TTL level in a fixed period of time, NSI 2000 can be configured to control the device
while scanning. If the device response time is known, NSI 2000 can be configured to wait a fixed amount of time after commanding the device and before taking the measurement.

Custom Closed-Loop Interfaces

If a script routine or open-loop interface does not meet your needs, NSI can modify the NSI 2000 software to make a custom version for your application. NSI has done this for several customers that required a custom interface to their proprietary beam steering computer, as an example.

Far-field Measurement Software

All control and setup functions are through the Measurement Software applications software. All software and hardware interfaces are included to permit high-speed single axis (multi-axis with optional model tower) and multi-frequency on-the-fly data collection.

A simple Windows interface allows the operator to enter all the measurement parameters on a single screen. Parameters defining the test frequency, positioner limit positions, angular span, and data density are entered by the operator and then verified by the system prior to the start of testing. Units for all entries and documentation can be switched between English, MKS, and wavelengths with a single keystroke. The operator is presented with a real-time display of the amplitude and current angular position on the setup screen. The measurement signal-to-noise ratio is calculated by the software and is also displayed.

Once the system is set up, the operator can ‘jog’ the positioner or command a move to any position using the keyboard and mouse. The amplitude and angular position are displayed in real-time to the operator. The system supports two data collection modes; one based on positioner angle, and the other based on time. The time-based mode plots the amplitude versus time base. This unique capability is useful in determining long term antenna’s electrical boresight, determining long term system drift, or other diagnostic functions. The angle based data collection mode permits the collection of amplitude versus positioner angle. The system automatically moves the azimuth stage to the operator-specified start angle then collects data at the specified angular sampling increment as it moves to the stop angle. As amplitude and phase data are collected by the system, they are presented to the operator on a confirmation plot. In case of emergency the operator can stop the data collection.

For an expanded description on the NSI Far-field Measurement Software, see the Far-field Section of the catalog.

NSI Software Product Datasheets

NSI 2000 Standard Edition Software

Upgrade NSI Standard Edition Software to Professional Edition

Motion Tracking Interferometer Software

Handheld Remote Control Unit


NSI Automation Scripts

MARS Reflection Suppression Software