Document ID: chunk:federal_register_of_legislation:F2023L00279:reg:1
Version: federal_register_of_legislation:F2023L00279
Segment Type: reg
Provision Reference: reg 1
Character Range: 22626–24021

1  Effective antenna height of a fixed transmitter
 (1) If:
 (a) subject to subitem (2), hgt is the vertical height in metres of the phase centre of a fixed transmitter's antenna measured with an error of less than 5 parts in 100 and relative to the point:
 (i) located on the line of intersection between the external surface of the structure supporting the antenna and the surface of the ground or sea; and
 (ii) having the lowest elevation on that line; and
 (b) subject to subitem (3), hs is the sum of:
 (i) the DEM-3S cell height of the location of the fixed transmitter as defined in Schedule 1; and
 (ii) hgt; and
 (c)  is the average ground height of the DEM-3S cell at each m-increment on each n-radial as calculated in accordance with item 2;
  then the effective antenna height  of the fixed transmitter is:
 (d) except where paragraph (e) applies:  (as shown in Diagram 1);
 (e) if  is less than hgt : hgt.
 (2) For a group of radiocommunications transmitters, hgt is the greatest of the hgt for each individual transmitter in the group, calculated in accordance with this item.
 (3) If the seconds component of the latitude or longitude of the fixed transmitter as defined in Schedule 1, plus 1.5, has a modulus of zero when divided by 3, then hs is the sum of:
 (a) hgt; and
 (b) the maximum height of the adjacent DEM-3S cells.

Diagram 1 Calculating effective antenna height