Near Field Antenna Test Chamber

The StarLab antenna test range uses an array of 15 scanning probes spaced every 22.5° in an arch round the DUT (device under test). To perform a full sphere measurement the DUT is rotated 180° around the Z axis. The probes array can rotate over ± 11.25 in elevation, such that the probes are positioned in offset locations. This oversampling effectively fills in the gaps between the probes. Combined with the electronic scanning of the probes, the mechanical elevation scanning allows fast and fully automated measurements. This means that full 3D radiation pattern measurements can be performed very rapidly compared to conventional single-probe systems. 

StarLab Axis Orientation
Probe Arrangement & Axis Oriantation
MVG StarLab Near Field Spherical Antenna Measurement Chamber
Antenna Test Facility

Oversampling - Resolution

The accuracy of the StarLab measurement system is a function of frequency, the diameter of the antenna, and the test system sampling resolution. For example, the table inset shows that oversampling the azimuth and elevation by a factor of x4 (22.5°/4 = 5.25°) results a maximum DUT size of 0.45 m at 5 GHz whilst maintaining the ± 1.1 dB peak gain accuracy. Note that with the correct calibration antennas the StarLab will work down to 0.65 GHz.

MVG StarLab Maximum DUT size versus over-sampling rate
Relationship between Oversampling & DUT Size

Peak Gain Accuracy

MVG StarLab S- Peak Gain Accuracy
Peak Gain Accuracy

 

The full MVG near field anechoic test system performance specification can be found here.