How do you know if the radio range of your FLARM installation is sufficient?
As you should know, verifying the radio range is crucial for any FLARM installation: cables, connectors, and antennas may slowly deteriorate due to oxidation, mechanical stress, or simply aging. Hence, the radio range should be checked regularly by using the online Range Analyzer tool.
The Range Analyzer works with one or more FLARM flight logs (IGC files). It uses data from received traffic for a statistical analysis, which is then presented graphically. For meaningful results, it requires a large number of contacts during flight – a record from a nice summer day is better than one from a night flight in the winter.
Storing all proximate traffic in the memory of the device is not possible. Until now, a majority of the data had to be discarded and could not be used by the range analyzer. The just-released CARP, or Continuous Analyzer of Radio Performance, solves this with a clever trick: The range statistics operations are performed on-the-fly, while the data is being received. The statistical range is continuously integrated over time with each aircraft that comes within, or disappears out of, range. Thanks to CARP, less flight time will be needed to get a range measurement and the measurement will be more reliable.
An example of the new CARP Range Analyzer results is shown below.
With FLARM firmware version 6.80 and later, CARP range data is automatically written to IGC files being recorded on the FLARM device after each flight. Each IGC file will thus contain both the new CARP data and the classic non-integrated, but quantitatively limited, data; the latter being used for e.g. SAR purposes.
Since CARP integrates the data over time without any restriction, it has to be reset manually when needed. If the data collection period is too long, a recent degradation in the installation quality might not be visible. It’s advisable to reset CARP at least once per year, e.g. during annual maintenance, after the old CARP data (latest IGC file) has been read out and retained. CARP is normally reset using the connected FLARM Compatible display. For displays that don’t have this capability, CARP can also be reset using the Configuration Tool.
CARP is available in all PowerFLARM-based devices which have firmware version 6.80 or above.