What are the limitations of Marine RADAR?

Limitations of Marine RADAR

1. Range Discrimination.

2. Bearing Discrimination.

3. Factors Affecting Minimum Range.

4. Factors Affecting Maximum Range.

5. Range Accuracy.

6. Bearing Accuracy.

1. Range Discrimination-

It is the ability of the RADAR to clearly distinguish two targets on the same bearing with a slight difference in ranges as two separate targets.

The factor which governs range discrimination is PL.

Pulse length makes all targets appear larger in radial depth by an amount equal to half PL in metres.

If the gap between the two targets is less than ½ PL in metres, then these targets would appear as one target on the PPI.

As per IMO Performance standards for RADAR, two small targets on the same bearing and separated by a distance of 40 metres on 1.5 miles range scale (placed at 50 to 100% of PPI), shall appear as two separate targets on the PPI.