Calculated Distances And Power Compliance Margins; Table 3 - Power Compliance Margins - Motorola PTP 400 Series User Manual

Peak power density in the far field of a radio frequency point source is calculated as follows:
(Note: Allowance should be made for any TDD structure employed)
2.1.1.1

Calculated Distances and Power Compliance Margins

Table 3 shows calculated minimum separation distances d, recommended distances and
resulting power compliance margins for each frequency band and antenna combination.
Band Antenna
Integrated
4.9 GHz
External
(max EIRP)
5.4 Ghz Integrated
Integrated
External 2ft
5.7 GHz
Flat Plate
External 6ft
Dish
1. Calculated
Notes:
1. The regulations cover the power averaged over a 6 minute period.
2. At 5.4GHz the product is generally to a fixed EIRP which can be achieved with the
Integrated Antenna. If there are no EIRP limits, use the distance calculations for 5.7GHz.
3. At 5.7GHz, for antennas between 2ft and 6ft, alter the distance proportionally to the
antenna gain.
Rearranging terms to solve for distance yields
=
d
Max RMS
Power in
P
Burst (Watt)
(Watt)
0.2 (23dBm) 0.1
0.2 (23dBm) 0.1
0.0025(4dBm) 0.0013
0.32 (25dBm) 0.16
0.32 (25dBm) 0.16
0.32 (25dBm) 0.16

Table 3 - Power Compliance Margins

21
⋅
P G
π
4 S
Variable
1
D
G S
(m)
2
(W/m )
158
10 0.35
(22dBi)
398
10 0.56
(26dBi)
200
10 0.04
(23dBi)
200
10 0.50
(23dBi)
631
10 0.90
(28dBi)
6310
10 2.83
(38dbI)
Recom- Power
mended Compli
Distance ance
(m) Margin
3 8.5
5 8.9
1 22.4
2 4.0
4 4.5
10 3.5