(12) where: : angle of incidence at height = 110 km i hr : radius of the Earth, 6 371 km R0 : elevation for the F2-layer mode (determined from equation (13)). F PART 2 Median sky-wave field strength 5 Median sky-wave field strength The predicted strength is the monthly median over all days of the month. The prediction procedure is in three parts, dependent on the path length. For path distances less than 7 000 km predictions of median sky-wave field strength are made using only the method given in § 5.2. For path distances greater than 9 000 km median sky-wave field strengths are made using only the method given in § 5.3. For path distances between 7 000 and 9 000 km both methods are used and the results are interpolated by the method described in § 5.4. 5.1 Elevation angle The elevation angle which applies for all frequencies, including those above the basic MUF, is given by: (13) : hop length of an mode given by = d n-hop d D/n : equivalent plane-mirror reflection height hr for E modes = 110 km hr for F2 modes is taken as a function of time, location and hop length. hr The mirror reflection height for F2 modes, is calculated as follows, where: hr, = foF2/foE and x with: and = or 1.8, whichever is the larger. y x a) For > 3.33 and = / foF2 1, is the wave frequency: x xr f f = or 800 km, whichever is the smaller (14) hr h where: = + 2.4–a for and 0 h A1 B1 B1 a = + otherwise A1 B1 with:
(12) where: i : angle of incidence at height hr = 110 km R0 : radius of the Earth, 6 371 km F : elevation for the F2-layer mode (determined from equation (13)). PART 2 Median sky-wave field strength 5 Median sky-wave field strength The predicted strength is the monthly median over all days of the month. The prediction procedure is in three parts, dependent on the path length. For path distances less than 7 000 km predictions of median sky-wave field strength are made using only the method given in § 5.2. For path distances greater than 9 000 km median sky-wave field strengths are made using only the method given in § 5.3. For path distances between 7 000 and 9 000 km both methods are used and the results are interpolated by the method described in § 5.4. 5.1 Elevation angle The elevation angle which applies for all frequencies, including those above the basic MUF, is given by: (13) d : hop length of an n-hop mode given by d = D/n hr : equivalent plane-mirror reflection height for E modes hr = 110 km for F2 modes hr is taken as a function of time, location and hop length. The mirror reflection height for F2 modes, hr, is calculated as follows, where: x = foF2/foE and with: and y = x or 1.8, whichever is the larger. a) For x > 3.33 and xr = f / foF2 1, f is the wave frequency: hr = h or 800 km, whichever is the smaller (14) where: h = A1 + B1 2.4–a for B1 and a 0 = A1 + B1 otherwise with:
R-REC-P.533-13-201507-I!!MSW-E.docx