Missing Data

“Missing azimuths” of raw radar data can be a symptom of a system operating close to the capabilities of the network to which it is attached.

If a radar is connected to a network that cannot support the required data rate, the raw data presented to connected systems will likely be degraded as shown below

Quick calculations show that a radar rotating at 4Hz, configured with a range-resolution of 4.4cm and an operating range of 330m in every azimuth will produce a stream that’s just under 100 Mbit/Sec. If there are multiple data consumers attached to the radar, then the required bandwidth will increase proportionately

The CIR radar will auto-negotiate its’ connection speed on a network, so it is worth ensuring that all switching equipment in the data chain is 1Gbit capable. There exists a setting in the web-interface for configuring the radar that sets an upper limit on the auto-negotiation speed, should that ever be required. As long as your network will support it, It would be worth checking that this value is set to 1000Mbps and not anything lower. The setting is part of the “System Configuration” page in the web user interface:

There are further ways to reduce the required bandwidth for the radar’s connection in to your system. The total number of reporting “bins” for each of the 400 azimuths of each rotation can be reduced; it makes sense to do this when customers can be sure that they are not interested in radar returns beyond a certain range.

This can be adjusted, either by implementing an overall maximum-operating-range for the unit, or can be implemented on a per-angle basis, where a “contour” can be defined that allows for a particular shape of data to be returned.

Setting a fixed range limit that applies to all azimuths can be easily done through the web user interface – log in with the “Engineer” account and navigate to the Factory>Configuration page to find this setting:

The process to make this adjustment is presented in this “how-to” video.

Setting the range limit on a per-angle basis is more involved, and is described as “Contour Update Message” here.