Delivering a cost-effective yet robust and accurate DF solution for government, military, and law enforcement applications, the WiNRADiO WD-7200 direction finding system employs a sophisticated correlative-vector matching interferometer DF method, combined with statistical signal processing.
The system is small, lightweight, and ruggedized. It is suitable for stationary, vehicle-mounted, and transportable deployment. It delivers unparalleled flexibility due to its SDR architecture. It's excellent precision and sensitivity ensure it is capable of filling the role of both of a direction-finding system and a highly capable HF/VHF/UHF COMINT intercept receiver system.
Each WD-7200 system consists of three core parts: antenna radome, twin coherent receivers, and processing computer.
The radome uses eight sense antennas in a circular array mounted in a weatherproof fiberglass housing. The sense antennas are specially designed dipoles. Inside the radome is an accurate magneto resistive digital compass, that ensures that the antenna is always accurately referenced to magnetic north.
The receivers are a quasi-coherent variant of the well-proven WR-G39DDC SDR. The system is housed in a rugged transportable pelican-style enclosure.
The WD-7200 exploits a special phase equalization technique that is both passive and dynamic, ensuring instantaneous optimum performance consistently.
The WD7200 DF technique allows DF and the exploitation of new digital waveforms that are not achievable with pseudo doppler and other analog systems. These include DMR/MOTOTRBO, dPMR, NXDN, D-STAR and APCO P25 (phase 1 and phase 2).
TheWD-3300 system satisfies the need for a flexible, transportable, affordable and easily deployable direction finding system.
It is a ruggedized transportable DF system with fully integrated receivers, a battery, a charging unit, and control circuitry in a compact carrying case. This system is ready for a quick and easy deployment anywhere, with or without external power sources , and features a high contrast display.
Additionally, standard laptop computer facilities can be used simultaneously for other applications. The unit contains one or more Winradio card receivers with a wide frequency range of 20 MHz to 1.8 GHz (receiver range can be extended to 3.5 GHz with option).
For maximum operator convenience, the bearings are displayed numerically, both as instantaneous and averaged values.The circular azimuth display, with a freely adjustable North reference, has an additional “polar mode”. This allows the user to evaluate the signal strength in relation to the trace length. An adjustable trace decay time can assist with recognizing random reflections. The direction finding software conducts statistical calculations and displays the results in several ways. This allows the signal direction to be determined even in the most difficult conditions.
The waterfall and histogram graphics provide an immediate overview of the signal bearing distribution over time, assisting in validating the quality of the signal azimuth indicators.
This system is designed to provide precise direction finding (DF) for HF signals. It has a frequency range of 500KHz to 40 MHz. It employs a sophisticated phase-coherent multi-channel interferometer-based method, combined with statistical signal processing. This delivers a cost-effective, robust, and precise HF DF solution. This system is designed for the for government, military, and law enforcement applications that require geo-locate HF emitters.
The system is small, lightweight, ruggedized, making it suitable for deployment in stationary and portable situations. Each WD-6300 system consists of three core parts: antenna array, three phase-coherent receiver channels, and associated processing computer.
The WD-6300 is a true none-commutated system that provides excellent performance against short duration signals. The sensing antennas utilized are specially adapted AX-81SM active monopoles. The antenna array size can simply be adjusted to match the system's desired frequency range. The antennas are positioned in a “L”-shape configuration, with each leg typically 5 meters in length for optimum coverage from 3 MHz to 30 MHz, and typically 10 meters for best coverage between 1 MHz to 15 MHz.
In addition to precise azimuth measurements, the WD- 6300 system can also measure an incoming signal's elevation. Providing the height of the reflecting ionospheric layer allows for an estimation of the target’s location without resorting to a standard multi-sensor approach for the necessary triangulation.
The entire antenna array can be assembled in less than thirty minutes by two people, while the receivers and the processing computer system can be operated either stationary or installed inside a suitable vehicle.
Most Direction Finding Systems use the “Wattson-Watt” technique of interferometry to determine the azimuth to the target emitter. These techniques are susceptible to signal reflection from adjacent obstacles or other environmental conditions. The cutting-edge Winradio TDOA V/UHF position fixing system overcomes these limitations by utilizing a highly sophisticated “Hyperbolic Position Finding” method, also known as “Time Difference Of Arrival” (TDOA) system. The signal propagation delay time is analyzed as it is being received from spatially separated receiver positions, and computed against their exact location in combination with a high-precision time reference. This technique is very robust against environmental radio frequency reflection conditions, enabling highly accurate and stable azimuth readings for pulsed signals, as well as phase and frequency modulated signals.
The core of the TDOA PF system is the main processing station. It consists of a powerful industrial computer system with high-speed networking capabilities. The processor analyzes incoming data from at least two receiver stations that are deployed at suitably placed positions.
It is strongly recommended to use more than three receiver systems. However, four or more radio receiver stations are preferable because it will eliminate signal ambiguity, increase the robustness against environmental reflection conditions, and improve the azimuth readout accuracy even further.