Technology
Key properties of the high-performance pan/tilt systems required to enable these applications include:
• Accurate — to provide accurate pointing, geo- pointing, and tracking
• Real-time control — responsive and repeatable communications, high command rates for tracking
• Durable — provide 24/7 operation for mission- critical applications • All-weather — deployable in any environment • Compact — good weight-to-power ratio to support mobility, smaller masts, and small footprints
Figure 2: WIN-T Tactical Communications Node (TCN)
1˚. Manual pointing of these systems adds significantly to setup time and can be difficult, so many system designers are now incorporating automated pointing by utilizing pan/tilt systems. When setting up the antenna, the position of the other antenna is entered by the user or received via out-of-band telemetry. The automated pointing system then calculates the required pointing angles using the positions of each antenna. Signal strength can then be used to fine-tune the pointing.
UAVs have become a crucial component of battlefield situational awareness. Early UAVs would collect and store sensor data aboard the aircraft, and then the data would be removed from the aircraft for processing and analysis after the flight. In today's battlefield, it is crucial to have access to this sensory data in real time. That means beaming the information to the ground wirelessly. With sensor resolutions ever growing, the requirement for bandwidth to download UAV sensor data is substantial. High-gain antennas are again required. These antennas are mounted on computer- controlled pan/tilt systems, typically integrated as part of the UAV ground-station system. Telemetry from the UAV, including position data, is used to automatically aim the pan/tilt at the UAV to maintain the antenna signal and thus enable real-time video download. The ground-station antenna system can also be fitted with cameras to provide imagery of the vehicle in flight, further aiding the operator.
In addition, mobile applications often utilize inertially stabilized pan/tilt positioners to maintain the antenna pointing angle during vehicle motion and maneuvers. The applications outlined above are currently being deployed on today's battlefield. The following sections will detail specific U.S. military programs that incorporate advanced pan/tilt technology.
Figure 3: Pan/tilt-controlled antenna on TCN
WIN-T – Rapidly Deployed Communications PM Warfighter Information Network-Tactical (WIN-T) is the U.S. Army's $10 billion program to provide the warfighter with robust battlefield
www.vertmarkets.com/electronics ■ Electronic Military & Defense 21