What can be done to increase the coverage area of a WLAN?

• A. Increase the transmission power, replace the omnidirectional antenna with a parabolic antenna, and use the 2.4 GHz radio band instead of the 5 GHz radio band.
• B. Decrease the transmission power and replace antennas with smaller ones.
• C. Move to 5 GHz exclusively and use a smaller channel width.
• D. Disable APs and rely on client devices.

Answer: (A)

The idea behind increasing WLAN coverage is to propagate a stronger, more easily received signal over a larger area. Raising the transmit power makes the signal detectable farther from the access point, while using a higher-gain, directional antenna (instead of a 360-degree omnidirectional one) concentrates that energy in a specific direction, pushing the usable range farther. Choosing the 2.4 GHz band helps because its longer wavelength generally propagates through walls and obstacles more effectively than 5 GHz, giving better coverage at the same distance. Put together, boosting power (within legal limits), employing a high-gain directional antenna, and operating on the 2.4 GHz band can extend the reach of the wireless network.

Keep in mind practical caveats: regulatory limits control how much power you can legally emit, and a parabolic or other directional antenna must be properly aimed to avoid creating coverage gaps or interference in unintended areas. The 2.4 GHz band can also be more crowded, which might affect performance even as it increases range.

In contrast, lowering power and using smaller antennas reduces coverage; moving entirely to 5 GHz with a smaller channel width shortens range and worsens coverage; and turning off APs eliminates coverage altogether.