FAQ
MilliBox Systems
A MilliBox antenna test system is composed of two main parts: a chamber and a gimbal.
- The chamber is shipped flat-packed and partially assembled. An assembly manual and tools are provided to guide you through the chamber assembly. A typical assembly will require 2 people and can be completed in a couple of hours.
- The gimbal comes with a positioner, laser guide, power supply, USB dongle, software controller written in Python, and a detailed user manual. This allows full control of the gimbal's movement and calibration. There is also a matching horn post and horn clamp that can accommodate waveguide flanges from WR2.2-WR34.
The following ARE NOT included with the MilliBox and must be provided separately: horn antenna, waveguide-to-coax adapters, cables, and test equipment.
We can sell the chamber by itself or the gimbals as a stand-alone unit. Please contact us at [email protected] for more information.
MilliBox Chambers
MilliBox is intended to be used for over-the-air (OTA) measurements of antennas operating in the far-field region. The far-field region depends on the frequency and antenna size. If the maximum linear dimension of the antenna is D and the wavelength is λ, then the common rule of thumb is that the measurement distance R > 2D²/λ.
MilliBox can be configured to have different R. The table below shows the calculated D for different operating frequencies and MilliBox configurations.
MAX ANTENNA DIMENSION (D IN CM) FOR FAR-FIELD MEASUREMENT
| 24GHz | 28GHz | 39GHz | 57GHz | 60GHz | 71GHz | 77GHz | 95GHz | |
| MBX02 | 6.9 | 6.4 | 5.4 | 4.5 | 4.4 | 4.0 | 3.9 | 3.5 |
| MBX03 | 9.3 | 8.6 | 7.3 | 6.0 | 5.9 | 5.4 | 5.2 | 4.7 |
| MBX04 | 11.1 | 10.3 | 8.7 | 7.2 | 7.0 | 6.5 | 6.2 | 5.6 |
Absolutely! One of the key benefits of the MilliBox product line is its modularity. We sell extension kits that can be used to extend your existing MilliBox by one or more modules to meet your evolving needs.
MBX02, MBX03, and MBX04 are the most popular solutions that apply to a large range of mmWave applications. These chambers have the benefits of being compact, lightweight, and portable, and they can achieve a far-field distance ranging from around 70cm to 2m.
However, we know that your application may have special requirements, and we have worked with numerous customers in the past to tailor our chambers to their unique needs. If you need something different from our standard products, please contact us at [email protected], and we would be happy to have a technical discussion to determine whether a custom MilliBox could work for you.
The MilliBox has 8cm (3") diameter direct pass-through holes in the deck located beneath the gimbals. This hole allows direct routing of all the connections needed for the DUT. This could include a combination of RF, analog, and digital signals, along with power. Allowing a direct connection without ports provides the most flexibility and also minimizes the RF loss when connecting to test equipment that is placed in the instrument bays below the MilliBox.
However, we know that your application may have special requirements, and we have worked with numerous customers in the past to tailor our chambers to their unique needs. If you need something different than our standard products, please contact us at [email protected], and we would be happy to have a technical discussion to determine whether a custom MilliBox could work for you.
MilliBox Gimbals
- The standard GIM01 that comes with a MilliBox is rated for a DUT of up to 0.5kg. The mounting area is spaced for a DUT of up to 11cm (W) x 20cm (H) x 4cm (D).
- The GIM03 can accommodate larger loads. The max DUT size on the GIM03 has been increased to 27cm (W) x 30cm (H) x 10cm (D), with a max weight of 3kg.
- The single-axis GIM1D has no restriction on DUT width since the DUT is mounted from the back. The weight limit for a GIM1D is 5kg.
The 2-axis gimbals (GIM01, GIM03) can rotate -180° to +180° in both the H and V planes. The 1-axis GIM1D can rotate -180° to +180° in the H plane only. All gimbals use stepper motors with absolute position encoders and have a resolution of < 0.1°.
The GIM1D is a single-axis gimbals that rotates in the H-plane (azimuth) only. The key benefits are:
- It can hold a larger DUT – no limit on DUT width and a weight of up to 5kg.
- Since the mounting is from the back, these gimbals provide the largest unobstructed view when measuring at very wide azimuth angles.
Software
The provided Python software fully controls the gimbal movement and calibration. In addition, the software includes sample code to interface to typical test equipment. Since the only requirement for the test equipment is that it needs to be able to be controllable using the Python VISA API, this covers the majority of modern test equipment from most manufacturers. Typical sweeps (1D, 2D) and plotting functions for radiation pattern characterization are also included.
The complete Python software is provided in the source. It is common for our customers to use it as a base and add software enhancements to the code that are specific to their DUT, their test equipment, or their measure. It is also possible to port the Python code to other environments such as MATLAB, LabView, or Keysight VEE.
No, you do not need to rewrite the software! The software for the GIM01, GIM1D, and GIM03 is fully compatible. The only difference is that for the single-axis GIM1D, some functions that control the V motor are disabled.
Options and Customizations
We offer many different options and accessories that include but are not limited to: receiver mounts for mixers, dual-polarized horn antenna mounts, trihedral reflector mounts for radar, linear actuators, and sniffer mounts.
In addition, it is possible to customize various parts of the MilliBox to tailor it to your application. This includes creating custom DUT mounts to attach the DUT to the gimbals, changes to the panels with additional holes or mounting points, and adjustments to the gimbals platform.
Please contact us at [email protected] to discuss your requirements.