In this session of our series on Direction Finding, we will delve into the intricacies of how DF antennas behave when incoming signals arrive from unexpected elevation angles. The DF performance provided in brochures and datasheets often only indicates how DF antennas will behave under ideal conditions, and with signals arriving perfectly parallel to the horizon. In real life, however, signals are rarely this well behaved, leading to reduced performance compared to what may be expected. It is thus important for System Engineers to understand how their specific application may lead to reduced DF accuracy when dealing with off-horizon incident signals, and how to choose an appropriate algorithm and antenna to ensure optimum performance of the overall DF system.
Topics that will be covered:
- How do off-horizon incident signals originate?
- Why are off-horizon incident signals bad for DF accuracy?
- How do various DF approaches (Watson-Watt, Interferometry, Correlative DF) behave when confronted with off-horizon incident signals?
- Strategies for mitigating elevation-related issues.
- Possible future technologies dealing with elevation-related topics in DF.