Document ID: chunk:federal_register_of_legislation:F2020L01460:reg:10:p3
Version: federal_register_of_legislation:F2020L01460
Segment Type: reg
Provision Reference: reg 10 (pt 3/4)
Character Range: 21447–24099

is determined in accordance with Part 2 of Schedule 3 to this instrument.
   3. In implementing the method in section 4.5.2 of Recommendation ITU-R P.526-15:
         (a) the path profile is developed by sampling the DEM-3S at 100 metre increments along each radial; and
         (b) at each increment along the path profile, the procedure for calculating the average ground height described in Part 2 of Schedule 3 to this instrument is used.
   4. In implementing the method in section 3.2 of Recommendation ITU-R P.2108-0:
         (a) the percentage of locations is set at 0.0001% and the correction is applied at only one end of the path;
         (b) if the loss calculated using the method in section 3.2 of Recommendation ITU-R P.2108-0 is less than 0 dB, the calculated loss value is replaced with 0 dB.

Schedule 3 Antenna height and average ground height
  (section 10, items 2 and 3 of Part 3 of Schedule 2)

Part 1  Antenna height of a transmitter
   1. The antenna height of a fixed transmitter is the vertical height in metres of the phase centre of the transmitters's antenna, measured with an error of less than 5 parts in 100 and relative to the point:
         (a) 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
         (b) having the lowest elevation on that line.
   2. For a group of radiocommunications transmitters, the antenna height for the group is the greatest of the heights of each individual transmitter in the group, calculated in accordance with this Part.

Part 2  Average ground height
   1. The average ground height at the mth increment on the nth radial is calculated as follows:
    Step 1: Determine the associated latitude and longitude of the mth increment on the nth radial, (lmn, Lmn), as calculated in Part 3 of this Schedule.
    Step 2: Identify the DEM-3S cell represented by (lmn, Lmn).
Note: See item 2 below for identifying the DEM-3S cell in a particular case.
    Step 3: Bound the identified DEM-3S cell with the 8 adjacent DEM-3S cells in a 3 x 3 matrix and obtain each DEM-3S cell height attribute (as shown in Diagram 1).
    Step 4: Determine the average value of the 9 DEM-3S cell heights for each cell in the the 3 x 3 matrix.
Diagram 1 Calculating average ground height
   2. If (lmn, Lmn) has a modulus of zero when divided by 0.000833333, then the corresponding DEM-3S cell, for the purposes Step 2 in item 1, is the adjacent DEM-3S cell with the minimum height.
Note: Additional information for the case where (lmn, Lmn) corresponds to a DEM-3S cell boundary is provided in the document