CWDP CWDP Antenna Design and Placement 2

Question 1

In the US, the FCC limits maximum EIRP for point-to-multipoint 5 GHz outdoor links to which value?

Accepted Answer

36 dBm

Answer

The FCC limits point-to-multipoint EIRP in the 5 GHz UNII bands to 36 dBm for outdoor use.

Question 2

What is the half-power beamwidth (HPBW) of an antenna?

Accepted Answer

The angle at which the antenna gain drops to 3 dB below peak

Answer

HPBW is the angular width measured between the two points where gain falls to half (-3 dB) of its maximum value.

Question 3

A designer wants to mount antennas in the ceiling of a 10,000 sq ft warehouse. What spacing consideration is most critical?

Accepted Answer

Ensuring overlap of approximately 15–20% between cell edges

Answer

A 15–20% cell-edge overlap ensures seamless roaming and prevents coverage gaps in large open spaces.

Question 4

Which cable type is preferred for short indoor antenna runs to minimize insertion loss?

Accepted Answer

LMR-400

Answer

LMR-400 has lower attenuation per foot than RG-58 or RG-8, making it preferred for minimizing cable losses.

Question 5

What effect does each 3 dB increase in antenna gain have on the effective coverage radius (assuming free-space path loss)?

Accepted Answer

Increases radius by approximately 41%

Answer

A 3 dB gain increase doubles the power density, which increases the free-space coverage radius by roughly 41%.

Certified Wireless Design Professional (CWDP) Practice Test