CXtec NEW COMPATIBLE 2.2 DBI RUBBER DUCK ANTENNA WITH RPTNC FEMALE Guia De Especificaciones

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dBm

30 dBm

1000 mW (1 W)

-30 dBm

0.001 mW

40 dBm

10,000 mW (10 W)

-40 dBm

0.0001 mW

Outdoor Range

The range of a wireless link is dependent upon the maximum allowable path loss. For outdoor links this is a straightforward calculation as long as

there is clear line of sight between the two antennas with sufficient clearance for the Fresnel zone. For line of sight, you should be able to visibly see

the remote locations antenna from the main site. (Longer distances may require the use of binoculars). There should be no obstructions between the

antennas themselves. This includes trees, buildings, hills, and so on.

As the distance extends beyond six miles, the curve of the earth (commonly called earth bulge) affects installation, requiring antennas to be placed

at higher elevations.

Fresnel Zone

Fresnel zone is an elliptical area immediately surrounding the visual path. It varies depending on the length of the signal path and the frequency

of the signal. The Fresnel zone can be calculated, and it must be taken into account when designing a wireless link (Figure 7).

Figure 7. Fresnel Zone

Based on both line-of-sight and Fresnel zone requirements, Table 3 provides a guideline on height requirements for 2.4 GHz antennas as various

distances. This refers to height above any obstacles located in the middle of the RF path.

Table 3. Guideline on Height Requirements for 2.4 GHz Antennas

Wireless Link

Distance (miles)

Approx. Value “F” (60% Fresnel Zone)

Ft.

2.4 GHz

Approx. Value “C” (Earth Curvature)

Value “H” (mounting Ht.)

Ft.

with No Obstructions

115

150