TP-Link CPE Series Installation Guide

18
Q2. Ho
w to calculate the minimum mounting height of
the devices?
I
n order to maximize the received signal strength of the devices,
installers need to minimize the eect of the out-of-phase signals,
which is caused by obstacles in the path between the transmitter and
the receiver. Fresnel Zone is a usual method to calculate this path, as
shown in the formula and the gure below.
where,
r = F
resnel zone radius in meters
c = 3x10
8
m/s
, speed of light
f = operating frequency of the devices in Hz
d1 & d2 = the distances between the point
and the devices in meters
h = the height of
obstacle at this point
H h+r
*
(1 40%)
(H is the height of the CPE)
For example, assume d1 is 2km, d2 is 8km, and f is 2.4GHz, then r
would be 14.142m. Considering a toleration of 40%, allowable radius
would be 8.485m. Assume h is 10m, then the result of the minimum
mounting height based on this point would be 18.485m. Similarly,
calculate the results based on all the points where there are obstacles,
and the maximum value would be the nal result.
For more information, please refer to:
http://en.wikipedia.org/wiki/Fresnel_zone
f
c
d
d
dd
r ⋅
+
×
=
2
1
21
d2
r
d1

TP-Link CPE Series Specifications

General

Model	CPE Series
Wireless Standards	IEEE 802.11a/n
Frequency	5 GHz
Antenna	Directional
Wireless Security	WPA/WPA2, WPA-PSK/WPA2-PSK
Operating Modes	Access Point, Client, Repeater, Bridge
Power Supply	Passive PoE (Power over Ethernet)
Operating Temperature	-30°C to 70°C
Storage Temperature	-40°C~70°C (-40℉~158℉)
Humidity	10%~90% non-condensing
Enclosure	Weatherproof design
Chipset	Atheros
RAM	Varies by Model
Flash Memory	Varies by Model
Ethernet Ports	1