CWNA-109 Practice Test

CWNA-109 practice test: what's covered

• RF Fundamentals
• 802.11 Standards
• WLAN Architecture
• Wi-Fi 6/6E
• WLAN Security (WPA3)
• Site Survey & Troubleshooting

Free CWNA-109 sample questions

1. A wireless engineer walks a warehouse and notices the signal weakens sharply when an AP's coverage must pass through a concrete-and-rebar firewall. The energy that fails to pass through is converted to heat inside the wall. Which RF behavior best describes this loss of signal as it travels through the dense material?

   • A. Absorption
   • B. Reflection
   • C. Diffraction
   • D. Refraction
   Show answer

   Correct: A. Absorption occurs when RF energy passes into a material (concrete, water, brick) and is converted to heat, reducing amplitude. Reflection bounces the wave off a surface, diffraction bends it around an edge, and refraction bends it as it passes between media of differing density.

2. In an open office full of metal filing cabinets and glass walls, a laptop receives the same transmitted signal multiple times via different bounced paths, arriving at slightly different times. Sometimes this causes data corruption and lower throughput. What is this phenomenon called?

   • A. Multipath
   • B. Free space path loss
   • C. Scattering
   • D. VSWR
   Show answer

   Correct: A. Multipath is the arrival of multiple copies of the same signal via reflected paths at different times/phases. Depending on phase it causes upfade, downfade, nulling or corruption. FSPL is distance-based loss, scattering is reflection off many tiny objects, and VSWR is an impedance mismatch metric.

3. A point-to-point bridge link must cross a fence topped with chain-link mesh and tree branches that break the wave into many small reflections sent in many directions. Which RF behavior is most responsible for this break-up of the signal off small, uneven surfaces?

   • A. Scattering
   • B. Reflection
   • C. Absorption
   • D. Diffraction
   Show answer

   Correct: A. Scattering is reflection off many small, irregular objects (mesh, foliage, dust, rain) that redirects the signal in many directions, weakening the primary path. A large smooth surface produces ordinary reflection; an edge produces diffraction.

4. A long-range outdoor link shows signal still reaching a receiver that is hidden behind the corner of a building, even though there is no clear line of sight around the obstruction. The wave appears to bend around the building edge. Which behavior explains the coverage in this RF shadow?

   • A. Diffraction
   • B. Refraction
   • C. Multipath nulling
   • D. Absorption
   Show answer

   Correct: A. Diffraction is the bending of RF waves around the edges of an obstruction, filling part of the RF shadow behind it. Refraction is bending as the wave passes through media of different density (e.g., atmospheric layers), not around an obstacle's edge.

5. An engineer reviews a far-field coverage calculation and recalls that even in a perfect vacuum, an RF signal loses amplitude purely because it spreads out over an ever-larger area as it travels away from the antenna. What is this distance-based weakening called?

   • A. Free Space Path Loss (FSPL)
   • B. Absorption loss
   • C. Insertion loss
   • D. Return loss
   Show answer

   Correct: A. FSPL is the natural attenuation of a signal as the wavefront spreads over distance, independent of any obstruction. Insertion loss is from cables/connectors, return loss relates to impedance mismatch, and absorption requires a material in the path.

Last updated: 2026-10-19

CWNA-109 practice test FAQ