Project Radar
Scan Strategy
The initial scan strategy is as follows:
- Pulse Repetition Frequency = 620 (resulting in a maximum range of 240 km)
- Pulse length = 0.8 ms (equivalent to 120 m)
- Gate spacing = 500 m (equivalent to 3.33 ms)
- Number of samples (for averaging) = 30
- SQI = 40% [30-50%]; this is a noise filter
- Clutter filter = 4 [3-7 is ok]; this is a Doppler notch filter for ground clutter
- Range Normalized = On (this should always be on.)
- Unfolding = Off
- Noise level = 2 dB
- PPI scan rate at 20° s-1, set to complete a full 360° PPI before stepping up to the next elevation angle
- Elevation angle list (17 angles, in degrees): 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, 6.7, 8.0, 9.6, 11.5, 13.7, 16.2, 19.2, 22.6, 26.6, 30.8, 35.5
- Resulting volume scan time: about 6:30 minutes
- Volume repeat time set for 10:00 min (compromise with operational needs.)
Slight changes to the number of samples and the scan rate allowed for a volume repeat time of 6 min, which was utilized on the Al Dhafra radar for the 2001 winter project. The scan strategy was changed to the above parameters for the Al Dhafra and Dubai radars during the 2001 summer project (e.g., volume scans every 10 min). Subsequent investigation into dropouts of radar data showed that the EEC processor speed was not fast enough to allow for the theoretical scan rate, and therefore the scan rate was decreased to 17-18° s-1. This resulted in longer volume scan times, but still shorter than the volume repeat time of 10 min.
