WLAN Design & Site Survey Flashcards

What is 'throughput testing' in the context of a WLAN site survey?

Answer: Measuring actual data transfer rates at various locations throughout the facility

Throughput testing measures real data transfer rates at various locations to verify that the WLAN meets the bandwidth requirements of the intended applications.

Which best describes the key difference between coverage-based and capacity-based WLAN design?

Answer: Coverage-based focuses on geographic area coverage; capacity-based focuses on number of concurrent users and bandwidth

Coverage-based design ensures RF signals reach all areas, while capacity-based design accounts for the density of concurrent users and their collective bandwidth demands.

In a high-density WLAN deployment, what technique is most effective at reducing co-channel interference?

Answer: Reducing AP transmit power and deploying more APs with smaller cells

Reducing transmit power and deploying more APs creates smaller cells, allowing the same channels to be reused at shorter distances and reducing co-channel interference.

Why is Signal-to-Noise Ratio (SNR) more meaningful than RSSI alone when evaluating WLAN performance?

Answer: SNR indicates the difference between the signal and the noise floor, directly affecting achievable data rates

SNR measures how much stronger the desired signal is compared to ambient noise; a high SNR enables higher modulation rates and throughput, regardless of the absolute RSSI value.

Which set of elements should be included in a thorough site survey report?

Answer: AP placement, channel assignments, transmit power levels, coverage maps, and identified interference sources

A comprehensive site survey report must document AP placement, channel plan, transmit power settings, coverage heat maps, and all identified RF interference sources to provide a complete picture.

What is 'adjacent channel interference' in the 2.4 GHz band?

Answer: Interference between APs using channels that share overlapping frequency spectrum

Adjacent channel interference occurs when APs use channels that overlap in frequency; in 2.4 GHz, only channels 1, 6, and 11 are truly non-overlapping in the US.

What factor primarily drives the number of APs required in a capacity-based WLAN design?

Answer: The number of concurrent users and their aggregate bandwidth requirements

Capacity-based design is driven by how many devices must be supported simultaneously and what bandwidth each requires, which dictates how many APs are needed to avoid overloading any single radio.