Comprehensive and Detailed Explanation:
Return loss measures how well devices or lines match impedance, with higher values indicating better matching and less signal reflection. When measuring return loss through a cable with known loss, the actual return loss of the antenna is calculated by subtracting twice the cable loss from the measured value:
Measured return loss = 20 dB
Cable loss = 2.5 dB
Actual return loss = 20 dB - (2 × 2.5 dB) = 15 dB
However, since the question states the measured value is "larger than 20 dB," let's assume it's, for example,
22.5 dB:
Actual return loss = 22.5 dB - (2 × 2.5 dB) = 17.5 dB
An actual return loss of17.5 dBis considered acceptable and indicates a reasonably good impedance match, minimizing signal reflections.
Reference:CWDP-305 Study Guide, Chapter on Post-Design Validation - Antenna and Cable Testing.

Comprehensive and Detailed Explanation:
In predictive modeling for WLAN design:
B:Setting the AP transmit power to match the average client device capabilities (e.g., 25 mW) ensures a balanced link budget, promoting reliable two-way communication and accurate coverage predictions.
A:While default antenna patterns can be used, they may not accurately represent the actual deployment, especially if different antennas are planned.
C:Channel width settings should reflect the intended deployment plan, which may include 20 MHz, 40 MHz, or 80 MHz channels, depending on the environment and requirements.
D:Using pre-configured vendor-specific AP and antenna models in the predictive software ensures that thesimul-ationclosely matches the actual hardware characteristics, leading to more accurate predictions.
Reference:CWDP-305 Study Guide, Chapter on Advanced Site Surveys - Best Practices for Predictive Modeling.

Comprehensive and Detailed Explanation:
Including 5.5 and 11 Mbps as basic rates in a mixed 802.11b/g/n network necessitates the use of protection mechanisms, such as RTS/CTS or CTS-to-self, to prevent collisions between legacy 802.11b devices and newer 802.11g/n devices. These mechanisms introduce additional overhead, potentially reducing overall network throughput. Therefore, configuring 5.5 and 11 Mbps as basic rates will result in the constant use of protection mechanisms to maintain compatibility with 802.11b clients.
Reference: CWDP-305 Official Study Guide, Chapter on Infrastructure Design

To calculate the required transmit power (Tx Power) for a desired Effective Isotropic Radiated Power (EIRP), the following formula is used:
EIRP (dBm) = Tx Power (dBm) + Antenna Gain (dBi) - Cable Loss (dB)
Given:
Desired EIRP: 21 dBm
Antenna Gain: 5.85 dBd (which is approximately 8 dBi, since 0 dBd = 2.15 dBi) Cable Loss: (25 feet / 100 feet) * 4 dB = 1 dB Plugging into the formula:
21 dBm = Tx Power + 8 dBi - 1 dB
Tx Power = 21 dBm - 8 dBi + 1 dB = 14 dBm
Converting 14 dBm to milliwatts:
10^(14/10) # 25.12 mW
However, since 14 dBm is approximately 25 mW, the closest answer is:
answer:D
Reference: CWDP-305 Official Study and Reference Guide, Chapter on Infrastructure Design

When conducting a site survey, accurately determining ceiling heights is crucial for proper AP placement and coverage prediction.If ladder use is restricted, utilizing a laser distance meter provides a precise and cost- effective solution.Laser measures can quickly and safely determine vertical distances without the need for physical elevation.#### ###### # ###### ### The CWDP-305 Official Study and Reference Guide emphasizes:
"Laser distance meters are valuable tools during site surveys, allowing for accurate measurements of ceiling heights and other distances without the need for ladders or lifts." Reference: CWDP-305 Official Study and Reference Guide, Chapter on Advanced Site Surveys