Committee on Radio Astronomy Frequencies

Separation distance required for land MESs at 1.6 MHz

This routine calculates the separation distance for land MESs at 1.6 GHz required to protect the Radio Astronomy Service using Recommendation ITU-R P.452 while to estimate the atmospheric attenuation Recommendation ITU-R P.676 is used.

The calculation uses the geographic summation methodology. Since a generic solution is anticipated: no terrain model is included.

The calculation details and assumptions are outlined in ERC Report 26.

The protection criteria for Radio Astronomy are given in Recommendation ITU-R RA.769.

Notes:

  • This calculation is only applicable for frequencies of ~1.6 GHz
  • For distances within 100 km the modified Okomura-Hata model is used (as explained in ERC Report 26)
  • As in ERC Report 26, the width of a ring in these calculations is 10 km

    transmitting power level per MES (e.i.r.p.): (in dBW)
    frequency: (in MHz)
    bandwidth of transmitter: (in MHz)
    density of active users: (km-2)
    maximum permissible spectral power density: (in dB(Wm-2Hz-1))
    height MES: (in meters)
    height radio astronomy antenna: (in meters)
    percentage of time lost due to variable propagation: (this value should be 10% or less)
    initial inner radius of first circle from RAS site location: (in km)

    Fill in and click to get results
    or click reset to renew all parameters

    Last modified: March 5, 2004