Test stand for prototyping and verification of microwave devices in the millimeter range (5G mmWave)

The mmWave Test Stand allows engineers to set up spatial sweeps using a fine (dense) 3D grid and perform RF measurements on thousands of points in space using autonomous movement. That is, as soon as the sweep begins, the positioner and mmWave VST synchronize and operate independently using trigger signals, without the need to rely on software commands from the controller. Since this approach avoids the more time-consuming, software-driven "action -> stop -> measure" execution, the results will be ready in no time.

Consequently, validation engineers improve the resolution of beamforming measurements while reducing testing time. Using the mmWave OTA Validation benchmark, engineers can create, store, or share detailed parametric results.

Structural diagram of the mmWave OTA test bench

The test bench can perform transmission and reception tests using narrowband signals, and then generate and analyze broadband new radio waves. Unlike competing solutions, the NI approach does not require a separate VNA + VSG + VSA.

The mmWave OTA Test Bench takes advantage of NI's recently released mmWave VST and PXI backplane hard-clocking to create a fast, affordable, and ready-to-use OTA reference test system that engineers can tailor to their test needs. . In addition, using other platform elements such as TestStand and LabVIEW, the mmWave Test Stand enables users to customize their tests, create and store reports, and visualize their test results interactively.


Measurement options

• General isotropic sensitivity
• Total radiated power
• Effective isotropic radiated power
• Effective isotropic sensitivity
• Partial radiated power in the upper hemisphere
• Partial isotropic upper hemisphere sensitivity
• Incomplete isotropic sensitivity near the horizon
• Partial isotropic radiated power near the horizon
• intermediate channel

Protocols 
GSM, GPRS, EDGE, CDMA2000, CDMA 1xEVDO, CDMA 1xRTT, WCDMA, HSDPA, Wi-Fi 802.11 a / b / g, BLUETOOTH 802.15.1.2, PHS, TD-SCDMA, HSPA, WiMAX, GPS, DVB-H, A -GPS
The list of compatible protocols is constantly expanding. Contact us for updated information

mmWave VST for IF-to-RF and RF-to-RF measurements

 The NI mmWave VST's modular architecture allows it to scale with the diversity and complexity of 5G mmWave devices. Using the NI VST, engineers can quickly generate and analyze broadband IF and mmWave signals in the lab for OTA testing of 5G semiconductor devices.
 To test RF-to-RF devices, the mmWave OTA Validation Test reference architecture places mmWave VST radio heads with powerful bidirectional ports very close to the RF connectors on the outside of the anechoic chamber. Engineers can also use the VST IF ports to interface IF-RF DUTs.

mmWave VST architecture

 This approach creates:

• IF and millimeter wave signal generation and analysis capabilities for various types of DUT
• Future-ready, modular system that engineers can adapt without changing any other parts of the test solution as the 5G standard evolves to include higher frequencies
• A way to move the mmWave test ports closer to the device under test, minimizing signal loss and increasing the signal-to-noise ratio
• A complete test solution with high data rates and signal processing at the speed of the latest multi-core processors.

Isolated anechoic chamber RF

   Proper beamforming characterization of AiP devices requires a controlled and quiet RF environment in an anechoic chamber with high quality RF absorbent material that minimizes reflections. In addition, to ensure repeatable measurements, the motion system must provide high angular resolution and move to the exact point in space every time.
  The test stand includes a carefully selected anechoic chamber with a 2-axis (azimuth and elevation) DUT positioner at the bottom and a fixed measurement antenna at the top. This camera includes a National Instruments real-time motion controller that allows NI to use a fast continuous motion OTA testing method.
  The distance between the positioner and the DUT allows far-field testing of 5G mmWave AiP devices with an antenna aperture of 5 cm or less (according to 3GPP 38.310 specification for category 1 DUTs).

Anechoic chamber with high isolation mmWave

 This approach creates:

• IF and millimeter wave signal generation and analysis capabilities for various types of DUT
• Future-ready, modular system that engineers can adapt without changing any other parts of the test solution as the 5G standard evolves to include higher frequencies
• A way to move the mmWave test ports closer to the device under test, minimizing signal loss and increasing the signal-to-noise ratio
• A complete test solution with high data rates and signal processing at the speed of the latest multi-core processors.

Software

The Microwave Prototyping and Verification Testbed includes test software that helps engineers quickly set up extensive spatial sweeps to characterize their device's antenna patterns while they produce, visualize, store, or distribute detailed parametric data. results. 

Users can use the mmWave bench test software as a complete testing environment for OTA validation tests. Alternatively, users can include some of its components in their existing test environment or use individual components as standalone utilities.

OTA testing needs can vary greatly for different applications and DUT types. To help engineers adapt to different test situations, the mmWave OTA Validation Test Software offers a modular approach that is extensible for different user needs, such as custom DUT control, specific sweep configurations, signal routing, and more.

Engineers working on both manual and automated mmWave OTA device validation tests will benefit from the following components built with LabVIEW and TestStand:

• mmWave OTA test configuration user interface: An open-source LabVIEW graphical user interface (GUI) that helps users set up a test matrix to run, including measurement parameters, sweep options, and connection settings
• TestStand Template Launch Sequences: The mmWave OTA Validation Test Software installs test sequence templates that engineers can use to run configuration files they create using the mmWave OTA configuration user interface.
• mmWave OTA Test Positioner Soft Front Panel: The mmWave OTA SFP test positioner allows users to control the positioner interactively.
• mmWave OTA Test Visualizer: The mmWave OTA Test Visualizer completes the offline setup and analysis of OTA test data for antenna measurements. Engineers can use the mmWave OTA Test Visualizer to call up various result visualizations and analyze measurements and antenna patterns.
• OTA measurement interface: To simplify the process of storing measurement values, importing and exporting measurement data, and interpreting measurement results using automated sequences in TestStand.
• System Calibration Utility: NI provides the RF System Calibration Assistant, a free software utility that controls RF instruments, including an external RF power meter, to perform system loss calibrations on all RF equipment components along the signal path (cables, adapters, antennas, and etc.) considering both horizontal and vertical polarization.

Front Panel Test Configuration User Interface

Test Positioner SFP mmWave OTA