A bandpass filter has a maximum in-band loss of 1.5 dB, ripple of 0.4 dB, and a return loss of 15 dB. What is the minimum in-band loss?
Correct Answer: A
In a bandpass filter, the ripple refers to the variation in insertion loss within the passband.If the maximum in- band loss is 1.5 dB and the ripple is 0.4 dB, the minimum in-band loss can be calculated by subtracting the ripple from the maximum loss:blog.knowlescapacitors.com 1.5 dB (maximum loss) - 0.4 dB (ripple) = 1.1 dB (minimum loss) Therefore, the minimum in-band loss is 1.1 dB. Reference: CWDP-305 Official Study and Reference Guide, Chapter on ProtocolandSpectrum Analysis
CWDP-305 Exam Question 57
Given: You are evaluating the theoretical and real-world RF gain benefits of transmit and receive features introduced by 802.11 with MIMO. This exercise allows you to quantify the features value in a real-world environment. What is the maximum theoretical signal gain of chip-based TxBF and MRC (as features) when compared to the same AP using only a single antenna for transmit and receive (effectively simulating a 1x1 chip)?
Correct Answer: D
The maximum theoretical signal gain of chip-based TxBF and MRC depends on the number of antennas and the channel conditions. TxBF (transmit beamforming) is a technique that focuses the transmitted signal in the direction of the intended receiver, resulting in higher signal strength and less interference. MRC (maximum ratio combining) is a technique that combines the signals received by multiple antennas in an optimal way, resulting in higher signal-to-noise ratio and better performance. The theoretical gain of TxBF and MRC can be calculated as GTxBF=10log10(N) and GMRC=10log10(N) where N is the number of antennas. Therefore, the total gain of TxBF and MRC is Gtotal=GTxBF+GMRC=20log10(N) However, this is the ideal case and assumes perfect channel conditions and alignment. In reality, the gain is lower due to factors such as channel fading, antenna spacing, and feedback delay.According to the CWDP study guide1, the typical gain of TxBF and MRC is about 4-6.5 dBi for 2 antennas, 7-10 dBi for 3 antennas, and 10-13 dBi for 4 antennas.Therefore, the answer is D.References:1: CWDP Certified Wireless Design Professional Official Study Guide: Exam PW0-250, Chapter 8, page 267.
CWDP-305 Exam Question 58
In a convention center, you have received complaints about the WLAN infrastructure. At this moment, there are only two APs in one auditorium. After analyzing the situation, you determined that there are more client devices than the infrastructure was designed for. There are only two APs to support more than 300 devices using Wi-Fi at the same time. What should you do to make the Wi-Fi work as expected?
Correct Answer: A
This is a classic example of a WLAN designed for coverage but lacking capacity. Simply adding more APs without proper planning (option C) or increasing output power (option D) would likely lead to channel contention, co-channel interference, and degraded performance. A proper redesign would include: Evaluating user density Planning for spatial reuse Implementing low-power, high-density AP placement Selecting appropriate channels and RF tuning From CWDP-305: "High-density environments such as auditoriums require WLANs designed for capacity, not just coverage. This includes AP placement optimization, channel planning, and potentially microcell designs to manage client load effectively." - Reference: CWDP-305 Official Study and Reference Guide, Chapter on Designing for Specific Applications
CWDP-305 Exam Question 59
When using a WLAN design tool with propagation modeling capabilities, what critical step must be performed before adding APs, antennas, and attenuation factors like walls?
Correct Answer: D
Accurate WLAN design relies heavily on the precision of the floor plan used in predictive modeling tools. Before placing Access Points (APs), antennas, or defining attenuation factors, it's imperative to calibrate the floor plan. This involves setting a known scale, typically by measuring a known distance within the plan, to ensure that the software accurately represents real-world dimensions. Proper calibration ensures that signal propagation, coverage areas, and interference zones are accurately predicted, leading to a more reliable and efficient WLAN design. Reference: CWDP-305 Official Study and Reference Guide, Chapter on Advanced Site Surveys
CWDP-305 Exam Question 60
Main Topic:Infrastructure Design Question: An enterprise customer is subject to the highest standards for network uptime. When designing their wireless network, you should consider which of the following? (Choose all that apply)
Correct Answer: C,D
Comprehensive and Detailed Explanation: For enterprises requiring high network uptime, it's crucial to design for redundancy and failover in both the wireless and wired components of the network. This includes: Wireless and Wired Network Failover:Ensuring that both wireless access points and wired infrastructure have redundancy to prevent single points of failure. Physical Aspects (Power and Cabling):Implementing redundant power supplies, uninterruptible power supplies (UPS), and proper cabling practices to maintain network availability during power outages or hardware failures. Reference:CWDP-305 Study Guide, Chapter on Infrastructure Design - High Availability and Redundancy Planning.
