C-Band, Ku-Band and Ka-Band

Considerations

Which solution to choose depends today from commercial and less from technical factors, as no matter what frequency band used - both technologies supply internet services at acceptable quality.

L-Band (1-2 GHz) being a relatively low frequency, L-band is easier to process, requiring less sophisticated and less expensive RF equipment, and due to a wider beam width, the pointing accuracy of the antenna does not have to be as accurate as the higher bands.

Commercially it is fact that hardware for C-Band is significantly more expensive while the capacity is cheaper. So customers with large bandwith requirements preferably choose this technology.

Ku-Band on the other hand operates with smaller antennas and less expensive equipment, while the capacity price is higher than C-Band.

Ka-band provides increased spectrum compared to C-band and Ku-band, enabling greater volumes of traffic to be transmitted. Many industries are looking to Ka-band because the smaller end-user antennas (VSATs), increased mobility and higher bandwidths and speeds make the benefits of Ka-band satellite capacity an attractive offering.

L-Band (1-2 GHz)

Advantages:
  • Less disturbance from heavy rain fade
  • Less expensive hardware, can use smaller antennas
Disadvantages:
  • Only a small portion (1.3-1.7GHz) of L-Band is allocated to satellite communications on Inmarsat.
  • Since there is not much bandwidth available in L-band, it is a costly commodity.

C-Band (4-8 GHz)

Advantages:
  • Less disturbance from heavy rain fade
  • Cheaper Bandwith
Disadvantages:
  • Needs a larger satellite dish (diameters of minimum 2-3m)
  • Powerful (=expensive) RF unit
  • More expensive hardware
  • Possible Interference from microwave links

X-Band (8-12 GHz)

Advantages:
  • Operates with a smaller satellite antenna
  • More cost efficient than C-Band
Disadvantages:
  • Mostly Military use, not much commercial offerings

Ku-Band (12-18 GHz)

Advantages:
  • No interference from microwave links and other technologies
  • Operates with a smaller satellite dish (diameters from 0.9m) -> cheaper and more easy installation
  • Needs less power -> cheaper RF unit
Disadvantages:
  • More expensive capacity
  • Sensitive to heavy rain fade (significant attenuation of the signal) / possibly can be managed by appropriate dish size or transmitter power.

Ka-Band (27-40 GHz)

Advantages:
  • Higher speeds

  • Operates with a smaller satellite dish (diameters from 0.9m) -> cheaper and more easy installation

Disadvantages:
  • When high frequencies are transmitted and received in a heavy rain fall area, noticeable signal degradation occurs and is proportional to the amount of rain fall.

  • Downlink: Rain dissipates 3 to 10 times more energy at Ka-band than at Ku-band (11 GHz vs. 20 GHz)

  • Uplink: Rain dissipates 63 to 400 times more energy at Ka-band than at Ku-band (14 GHz vs. 30 GHz)

  • Ka-band is not available everywhere