Narda’s SignalShark range now ideal for radio monitoring and TDOA/AOA direction-finding

The successful SignalShark family from Narda Safety Test Solutions now has powerful support in handling the many challenges involved in effective radio monitoring and direction finding of interference signals. As the final piece in the jigsaw covering areas of application, the robust, weatherproof SignalShark Outdoor Unit will from now on primarily take on the job of 24/7 radio monitoring, particularly in the open air. Even under the most adverse conditions, it delivers precise, absolutely reliable signal detection and localization results, and operates completely autonomously thanks to its Power over Ethernet or solar panel supply. Equipped with the same measuring core and good DNA as its two older siblings, the Handheld and the Remote Unit, it too receives and analyzes radio signals at up to 8 GHz. With its real time bandwidth of 40 MHz, the Outdoor Unit is capable of broadband signal capture despite its compact size – highly sensitive, ITU compliant.

All three models in the SignalShark family use an integrated Windows 10 computer to operate as intelligent sensors, eliminating the need for an additional external PC at the location of use. The measuring receivers pick up the signals with the aid of an omnidirectional or a directional antenna, convert them to VITA49-compatible IQ streams and add high-precision timestamps. These timestamps are used by the Decodio Localizer software to quickly and exactly localize the sources of the captured signals. The SignalShark system, comprising one receiver and one antenna (ADFA), supports two methods of direction finding. The sources of the received signals can be reliably localized using TDOA (Time Difference of Arrival) or AOA (Angle of Arrival), and even a combination of both principles (hybrid). This has two considerable advantages: firstly, that the result is backed up by a second method; and secondly, that the accuracy of the localization is significantly improved by taking an additional bearing. Furthermore, in hybrid mode the two methods compensate for each other’s “blind spots”. The physics dictates that TDOA runs into trouble with CW signals, which are something that AOA is particularly good at, whereas AOA is deficient when it comes to dealing with short, pulsed signals, where TDOA really excels because of the steep signal slopes.

With the Outdoor Unit, the latest addition to the tried and tested SignalShark family, it is now possible to set up perfect, complete networks for radio monitoring that are efficient and right up to date, and which include state of the art direction finding. The powerful, battery operated Handheld — the original SignalShark — is light and robust and therefore ideal for mobile on-site operations. The Remote Unit has the same intrinsic qualities and its compact size and low power consumption make it outstanding as a “left behind” device, which can also be integrated into any standard 19“ rack. Finally, the new SignalShark Outdoor Unit is in many respects the ideal measuring unit for all applications involving long-term frequency monitoring in the open air.

The SignalShark trio therefore forms the perfect system for blanket coverage monitoring operations across different locations, in fixed measurement networks and for mobile operations with test and measurement vehicles. This could include frequency allocation monitoring, general observation of frequency ranges or occupancy testing, dealing with interference, or pirate radio transmitter detection. A central station running the Decodio Localizer application controls the individual sensor locations, which may be a considerable distance apart. No manual setting of the units at each sensor location is needed. Practically any communications system, from LTE through microwave links to private LAN, can be used to link the sensor locations to the central station. The entire organization of the recorded information, such as transmission of the data to the central station, is handled by the Decodio ReX software directly installed on the SignalShark itself.