Antenna provides localization of signals from 10 MHz to 8 GHz
PFULLINGEN, GERMANY. With the ADFA 2, Narda Safety Test Solutions announced it is presenting its second automatic direction-finding antenna. The RF measurement specialist has increased the frequency range in this automatic DF antenna by more than three times. When connected to Narda’s real-time receiver, the SignalShark, the antenna can precisely and reliably localize signals between 10 MHz and 8 GHz (vs. 200 MHz and 2.7 GHz for the ADFA 1). Just like its smaller “brother,” the ADFA 2 delivers stable measurement results in seconds and is insensitive to reflections. Its wide frequency range means that direction finding at low and high frequencies is covered equally. Compact and universal, it combines a broad spectrum with the minimum outlay of equipment. This makes the ADFA 2 particularly interesting for use by mobile network providers and regulatory authorities, as well as for military applications.
For applications on the move, the ADFA 2 is easily attached and detached from a car roof with the aid of its magnetic base. A single cable links it to the SignalShark. It delivers precise results with high accuracy even without the vehicle correction tables that are usually required. While still on the move, the measurement technician can superimpose a heatmap on a stored map on the SignalShark display as well as view the found direction. The localization software in the device automatically indicates where the interference source is most likely to be located. No additional PC or assistance is required.
The heart of the ADFA 2 is an array of nine antenna elements (dipoles) arranged on a flat plane with a central omnidirectional reference antenna, which allows the measurement technician to observe the signal spectrum during direction finding. The principle of automatic direction finding using single channel receivers is based on the phase difference between the antenna elements. The nine dipoles are here measured against the central reference antenna. The greater the distances between them and thus the detected phase difference, the more reliable the bearings. As a result of the extended frequency range at both ends of the scale there is a new lower plane for the range from 10 to 200 MHz and an upper one for the range from 2.7 to 8 GHz. While the external diameter of only 480 millimeters is unchanged, these additional planes mean that the ADFA 2 weighs 6.5 kg, which is just 1 kg more than the ADFA 1 (200 MHz – 2.7 GHz).