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Question: 1
What word describes the bending of an RF signal as it passes through a medium of a varying density from that of free space?
A. Diffraction
B. Reflection
C. Refraction
D. Diffusion
E. Scattering
Answer: C
Question: 2
What can cause an excessively high VSWR (Voltage Standing Wave Ratio) in a WLAN RF transmission line?
A. An impedance mismatch inthe RF cables and connectors
B. Reflected direct current (DC) voltage on the main RF signal line
C. Attenuation of the RF signal as it travels along the main signal path
D. Crosstalk (inductance) between adjacent RF conductors
Answer: A
Question: 3
What factors influence the distance that an RF signal can be effectively received? (Choose 3)
A. Transmitting station鈥檚 power source
B. Receiving station鈥檚 radio sensitivity
C. Free Space Path Loss
D. MAC layer encryption
E. Transmitting station鈥檚output power
F. Temperature in the Fresnel zone
Answer: B , C, E
Question: 4
As an RF wave propagates through space, the wave front experiences natural expansion that reduces its signal strength in an are
a. What term describes the rate at which this expansion happens?
A. MU-MIMO
B. Inverse square law
C. Fresnel zone thinning
D. Ohm鈥檚 law
Answer: B
Question: 5
Return Loss is the decrease of forward energy in a system when some of the power is being reflected back toward the transmitter.
What will cause high return loss in an RF transmission system , including the radio, cables, connectors and antenna?
A. A Voltage Standing Wave Ratio (VSWR) of 1:1
B. An impedance mismatch between components in the RF system
C. The use of cables longer than onemeter in the RF system
D. High output power at the transmitter and use of a low-gain antenna
Answer: B
Question: 6
What factors are taken into account when calculating the Link Budget of a point-to-point outdoor WLAN bridge link?
A. Operating frequency
B. Transmit antenna gain
C. Transmit power
D. Antenna height
Answer: A , B, C
Question: 7
A WLAN transmitter that emits a 200 mW signal is connected to a cable with 3 dB loss.
If the cable is connected to an antenna with 10 dBi gain, what is the EIRP at the antenna element?
A. 10 dBm
B. 13 dBm
C. 20 dBm
D. 26 dBm
E. 30 dBm
Answer: E
Question: 8
In a long-distance RF link , what statement about Fade Margin is true?
A. Fade Margin is an additional pad of signal strength designed into theRF system to compensate for unpredictable signal fading.
B. The Fade Margin of a long-distance radio link should be equivalent to the receiver鈥檚 antenna gain.
C. A Fade Margin is unnecessary on a long-distance RF link if more than 80% of the first Fresnelzone is clear of obstructions.
D. The Fade Margin is a measurement of signal loss through free space, and is a function of frequency and distance.
Answer: A
Question: 9
Which unit of measurement is an absolute unit that is used to quantify power levels on a linear scale?
A. dBm
B. SNR
C. RSSI
D. VSWR
Answer: A
Question: 10
An 802.11 WLAN transmitter that emits a 50 mW signal is connected to a cable with 3 dB of loss. The cable is connected to an antenna with 16 dBi of gain.
What is the EIRP power output?
A. 2 mW
B. 500 mW
C. 250 mW
D. 1000 mW
Answer: D
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The Important Stages Of ACL Physical Therapy: Is Recuperation Assured? Health Articles | July 30, 2011
The ligament which joins the femur bone to the tibia is what we the anterior cruciate ligament also referred to as ACL. This ligament lies diagonally in the middle of these two bone fragments. The ACL...
The ligament which joins the femur bone to the tibia is what we the anterior cruciate ligament also referred to as ACL. This ligament lies diagonally in the middle of these two bone fragments. The ACL is undoubtedly one of the many important ligaments in the body as it is the one that supports the knee and is also accountable for the rotating movement of the knee. As noted by numerous studies , on the hundred thousand people are advised to undergo the surgery to fix the ACL after their ligaments get torn due to physical contact in sports or other activities. As important as the actual reconstruction surgery will be the ACL physical therapy.
Just like with other kinds of physical injury, the body needs some time to recover from the surgery. After an ACL reconstruction surgery, the patient has to visit a physical therapist a minimum of three times every week. Generally , the physical therapist is recommended by the surgeon of the patient. The initial phase of the rehab process normally lasts eight weeks, after which the actual sessions can be reduced to just two times a week.
There are a couple of stages as part of the ACL physical therapy program of a patient. At first, the exercises are targeted at strengthening the affected knee. These exercises are also designed to reduce the swelling of the knee. It is crucial at this stage the patients keep doing the actual exercises even without the guidance of the therapist. Ideally , these strengthening workouts should be done for around 30 minutes every day.
Eight weeks after the beginning of the rehabilitation process, the physical therapist is likely to shift to another training program. This time, the individual will have to do some more difficult . |
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