Velocity unfolding
The RVP10 processor can unfold mean velocity measurements based on a dual -PRF algorithm.
In this technique, 2 radar PRFs are used for
alternate N-pulse processing intervals. The internal trigger generator
automatically produces the correct dual-PRF trigger. An external trigger can also be applied.
For external triggers, the ENDRAY_ output line indicates when to switch rates. RVP10 measures the PRF to determine which rate (high or low) was present on a given processing interval. It then unfolds based on a 2:3, 3:4, or 4:5 frequency ratio.
| PRF1 | PRF2 | Unambiguous range (km) |
Unambiguous velocity (m/s) |
Unfolding | ||
|---|---|---|---|---|---|---|
| 3 cm wavelength | 5 cm wavelength | 10 cm wavelength | ||||
| 500 | * | 300 | 3.75 | 6.25 | 12.50 | None |
| 1000 | * | 150 | 7.50 | 12.50 | 25.00 | |
| 2000 | * | 75 | 15.00 | 25.00 | 50.00 | |
| 500 | 333 | 300 | 7.50 | 12.50 | 25.00 | Two times unfolding |
| 1000 | 667 | 150 | 15.00 | 25.00 | 50.00 | |
| 2000 | 1333 | 75 | 30.00 | 50.00 | 100.00 | |
| 500 | 375 | 300 | 11.25 | 18.75 | 37.50 | Three times unfolding |
| 1000 | 750 | 150 | 22.50 | 37.50 | 75.00 | |
| 2000 | 1500 | 75 | 45.00 | 75.00 | 150.00 | |
| 500 | 400 | 300 | 15.00 | 25.00 | 50.00 | Four times unfolding |
| 1000 | 800 | 150 | 30.00 | 15.00 | 100.00 | |
| 2000 | 1600 | 75 | 60.00 | 100.00 | 200.00 | |