X & S band radar

Difference??

A higher frecuency gives you better resolution, but less radar distance. A smaller frecuency gives you less resolution but more radar distance.

KEY RADAR SPECIFICATIONS
X Band (IEEE)  navigation radar  or I band (NATO)
Frequency - 9,410MHz
Wavelength - 3.1859 cm
Power - 25 kW
Pulse Repetition Rate - 375 to 3000 pps
Antenna - 2.4 metre wide turning at 24 rpm. It is 15.7 m (51 ft) above the waterline
Antenna Weight - 20 kg
Radiation Hazard (Radhaz) - 1.5 m

S Band (IEEE) search radar or E,F band (NATO)
Frequency - 3,050 MHz
Wavelength - 9.8273 cm
Power 25 - kW
Pulse Repetition Rate - 375 to 3000 pps
Antenna - 4 metre wide turning at 22 rpm. It is 12.2 m (40 ft) above the waterline
Antenna Weight - 65 kg
Radiation Hazard (Radhaz) - 0.8 m

kingston_sband_ant_closeup.jpg
Closeup view of the S-band radar antenna. (Photo courtesy  Rick Bungay)

The X band can be set to short pulse for distances less than 1.5 nm, medium pulse for distances from 3 to 24 nm or long pulse for distances beyond 24 nm. 

The X band has proven superior to the S band even at the longer ranges for which the S band was designed.  Consequently, officers on the bridge using the Navigation radar often pick up contacts before the radar plotters in Operations do using the search radar.