Radar – Radio Detection and Ranging.
Principle: it Works on Echo Principle (Echo ranging by radar) which is based on time interval between the transmission of an EM pulse into the environment and reception of its echo.
- Instead of Sound wave it uses Radio waves.
- Radar transmission causes an electro-magnetic vibration which travels through air @300 m/per micro sec. [1,000,000 = 1 Sec]
Type:
| · X Band 3cm, 9 GHZ | · S Band 10 cm, 3 GHZ |
| · Can detect SART | · Better Target detecting in RAIN |
| · In fair weather target will show better | · Better for long range detection (radar horizon greater than 9 GHZ |
| · For high discrimination, good sensitivity and tracking performance. | · Good sea clutter response, tgt less likely to be hidden. |
| · Better for and Rain clutter. | |
| · Short Antenna | · Large Antenna |
Carriage Requirement: Min Radar/ARPA requirements [SOLAS Ch 5 – Annex 16]
| Gross Tonnage | 9 GHZ X Band | 3 GHZ S Band | EPA | ATA | ARPA |
| 300 – 500 | 1 | 1 | |||
| > 500 – < 3000 | 1 | 1 | |||
| 3000 – 10000 | 1 | 1* | 2 | ||
| 10000 + | 1 | 1* | 1** | 1 |
* Can be 9 GHZ, if administration consider it appropriate.
– MCA require reason why 3 GHZ Radar cannot be carried.
** Instead of APA it can be 2nd ARPA.
Performance Requirement:
| Size of Ship | < 500 GT | 500 < 10000 GT ( HSC < 10k GT) | All Ships 10000 GT and above |
| Min ops display area | 180 mm | 250 mm | 320 mm |
| Min Display area | 195 mm x 195 mm | 270 mm x 270 mm | 340 mm x 340 mm |
| Auto ACQ of target | – | – | Yes |
| Min ACQ Radar target cap | 20 | 30 | *40 |
| Min Activated AIS tgt cap | 20 | 30 | 40 |
| Min Sleeping AIS tgt cap | 100 | 150 | 200 |
| Trial Manoeuvre | – | – | Yes |
*Solas 8.6.3.1 Atleast 20 target can be acquired both manually ???
Limitations:
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