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In radar engineering, the frequency range is specified by the Institute of Electrical and Electronics Engineers (IEEE) as 8.0–12.0 GHz. The X band is used for radar, satellite communication, and wireless computer networks.
I/J- Band (X- and Ku- Band Radars) Between 8 and 12 GHz, the ratio of wavelength to antenna size has a more favorable value. With relatively small antennas, sufficient angular accuracy can be achieved, which favours military use as airborne radar.
The most common radar frequency bands are designated as L, S, C, X, Ku, and Ka bands. Each band has a specific range and is used for different purposes. Most of the radars operate in UHF as well as microwave frequency bands. Now-a-days radars even use millimeter bands.
19 Δεκ 2022 · X-band radar elements are typically spaced closer together than S-band. The spacing between antenna elements on a radar is designed to be less than 1/2 of the wavelength to avoid ambiguities. Higher frequencies have shorter wavelengths, and X-band is higher in frequency than S-band.
There are X-band radars with antennas up to 3 meters wide, and in this case the angular beam width is 0.75 degrees, which is very important for accuracy. On the other hand, Radomes, with an antenna width of about 40cm, have an average horizontal beam width of 5.7°.
The first group lies in the X-band which corresponds to a wavelength of 3 cm. and has a frequency range between 9300 and 9500 MHz. The second group lies in the S-band with a wavelength of 10 cm. and has a frequency range of 2900 to 3100 MHz.
X-band radar systems can be installed on moving vessels or on fixed platforms offshore or at coastal sites. The main limitations of X-band radar are the limited range, and the requirement for sufficient sea clutter (and associated significant wave height) to allow imaging of the waves.
