1.
What is the wireless communications technology used in retail operations to identify and secure merchandise?
Correct Answer
A. RFID
Explanation
RFID (Radio Frequency Identification) is the wireless communications technology used in retail operations to identify and secure merchandise. It involves using small tags or labels that contain a unique identifier and can be attached to products. These tags can be read by RFID readers, allowing retailers to track inventory, prevent theft, and improve overall supply chain management. RFID technology is widely used in the retail industry as it provides real-time visibility and accurate data about the movement and location of merchandise.
2.
What WLAN device provides communications management services to wireless workstations?
Correct Answer
A. Access Point
Explanation
An access point is a WLAN device that provides communications management services to wireless workstations. It acts as a central hub for wireless devices to connect to a wired network and provides a wireless signal for devices to access the network. It allows multiple devices to connect simultaneously and manages the communication between the wireless devices and the network, ensuring efficient and secure data transfer.
3.
What WLAN device is installed in or attached to a PC to provide an interface to a wireless network?
Correct Answer
A. Network Adaptor
Explanation
A network adapter is a device that is installed in or attached to a PC to provide an interface to a wireless network. It allows the PC to connect to and communicate with the wireless network, enabling the user to access the internet or other devices on the network wirelessly. The network adapter typically includes a radio transmitter and receiver, as well as software drivers that allow the PC to communicate with the wireless network.
4.
Question 04. What industry association develops, publishes, and maintains the standards for wireless networks?
Correct Answer
A. IEEE
Explanation
The correct answer is IEEE. IEEE stands for the Institute of Electrical and Electronics Engineers. It is a professional association that develops, publishes, and maintains the standards for various technologies, including wireless networks. They are responsible for ensuring interoperability and compatibility among different wireless devices and networks.
5.
What is the term used to identify the broadcast or generated electrical signals that can disrupt wireless communications?
Correct Answer
A. RFI
Explanation
RFI stands for Radio Frequency Interference, which refers to the broadcast or generated electrical signals that can disrupt wireless communications. These signals can come from various sources such as electronic devices, power lines, or other wireless systems. RFI can cause interference and degrade the quality of wireless signals, leading to communication disruptions or poor performance.
6.
Which of the FCC's RF bands operates in the frequency range of 4.9 GHz to 5.825 GHz?
Correct Answer
A. UNII
Explanation
The correct answer is UNII. UNII stands for Unlicensed National Information Infrastructure and it operates in the frequency range of 4.9 GHz to 5.825 GHz. UNII bands are used for wireless communication devices such as Wi-Fi routers and access points. These bands provide high-speed wireless connectivity for various applications including home networks, businesses, and public hotspots.
7.
A wireless extension to a wired network can eliminate the need for new __________ to be installed.
Correct Answer
A. Cables
Explanation
A wireless extension to a wired network can eliminate the need for new cables to be installed because wireless technology allows devices to connect to the network without the use of physical cables. This means that existing wired devices can be connected to the network wirelessly, eliminating the need for additional cables to be installed.
8.
Which one of the following is not a consideration when deciding between a WLAN and a wired LAN beyond the network medium?
Correct Answer
A. RF Interferences
Explanation
RF Interferences is not a consideration when deciding between a WLAN and a wired LAN beyond the network medium. RF Interferences refers to the interference caused by other wireless devices or environmental factors that can disrupt the wireless signal. While RF Interferences can impact the performance of a WLAN, it is still a consideration when deciding between WLAN and wired LAN, as both types of networks can be affected by RF Interferences. Therefore, RF Interferences cannot be the correct answer in this context.
9.
In a software world, __________ refers to the capability of a software program to run on different operating systems or hardware models.
Correct Answer
A. Portability
Explanation
Portability in the software world refers to the ability of a software program to be easily transferred or adapted to different operating systems or hardware models. This means that the software can run seamlessly on various platforms without requiring significant modifications or reprogramming. Portability is essential for developers and users as it allows for flexibility and accessibility, enabling the software to reach a wider audience and be used in diverse environments.
10.
This device serves as an interface point and bridge between wireless workstations and a wired network, so the wireless workstations can access the resources of the wired network.
Correct Answer
A. Access Point
Explanation
An access point is a device that allows wireless workstations to connect to a wired network. It acts as a bridge between the two, enabling the wireless workstations to access the resources of the wired network. This means that devices such as laptops or smartphones that are equipped with wireless capabilities can connect to the access point and then access files, printers, or other resources on the wired network. The access point essentially extends the reach of the wired network to wireless devices.
11.
A wireless __________ includes and supports the functions of an access point, a wireless switch, and a router.
Correct Answer
A. Router
Explanation
A wireless router includes and supports the functions of an access point, allowing devices to connect to a wireless network, a wireless switch, enabling communication between devices on the network, and a router, which directs network traffic between different networks. It combines these functions into a single device, making it a convenient and efficient solution for wireless networking. A bridge is a device that connects two different networks together, a PC Card is a type of expansion card for laptops, and a NIC (Network Interface Card) is a hardware component that allows a computer to connect to a network.
12.
Which one of the following devices rebroadcasts the signals it receives after conditioning them for increased strength and clarity?
Correct Answer
A. Repeater
Explanation
A repeater is a device that receives signals and then amplifies and retransmits them to extend the range of a network. It helps to overcome signal degradation and loss that occurs over long distances or due to obstacles. By conditioning the signals for increased strength and clarity, a repeater ensures that the transmitted data reaches its intended destination without any distortion or loss. Therefore, a repeater is the correct answer as it rebroadcasts signals after conditioning them for increased strength and clarity.
13.
Wireless networks transmit using RF signals, which require a __________ to receive and transmit signals through the air.
Correct Answer
A. Antenna
Explanation
Wireless networks transmit data using radio frequency (RF) signals. These signals need an antenna to both receive and transmit the signals through the air. Antennas are designed to pick up and emit these RF signals, allowing devices to connect to the wireless network and communicate wirelessly. Repeaters, routers, and remotes are not specifically designed for this purpose, making antenna the correct answer.
14.
Implementing wireless __________ requires the use of telephones that include an RF transmitter and antenna.
Correct Answer
A. VoIP
Explanation
Implementing wireless VoIP requires the use of telephones that include an RF transmitter and antenna. VoIP stands for Voice over Internet Protocol, which is a technology that allows voice communication over the internet. In order to use wireless VoIP, telephones need to have an RF transmitter and antenna to transmit and receive voice signals wirelessly.
15.
Which one of the following frequency bands is used for cordless phones?
Correct Answer
A. 900 MHz
Explanation
Cordless phones typically operate in the 900 MHz frequency band. This frequency range provides good coverage and penetration through walls and obstacles, making it suitable for indoor use. Additionally, the 900 MHz band offers a relatively low level of interference from other devices, ensuring clear and reliable communication.
16.
Which one of the following RF band is allocated to the Industrial, Scientific and Medical industry?
Correct Answer
A. 2.4 GHz to 2.4835 GHz
Explanation
The RF band allocated to the Industrial, Scientific, and Medical industry is 2.4 GHz to 2.4835 GHz. This frequency range is commonly used for various applications such as Wi-Fi, Bluetooth, and microwave ovens. It is designated specifically for non-licensed use by the ISM industry, allowing for the development and deployment of a wide range of devices and technologies.
17.
__________ can be grouped into two general categories: broadcast and electrical.
Correct Answer
A. RFI
Explanation
RFI stands for Radio Frequency Interference. It refers to any unwanted electromagnetic disturbance that disrupts the proper functioning of electronic devices or systems. RFI can be categorized into two general categories: broadcast and electrical. Broadcast RFI is caused by external sources such as radio and television transmissions, while electrical RFI is caused by internal sources such as power lines and electrical equipment.
18.
What wireless mode is being used by a student who uses a wireless connection to link to her lab partner's notebook PC in a study hall?
Correct Answer
A. Ad-Hoc
Explanation
The student is using the Ad-Hoc wireless mode to connect to her lab partner's notebook PC. Ad-Hoc mode allows devices to connect directly to each other without the need for a central access point or router. This mode is commonly used for peer-to-peer connections, such as between two devices in close proximity like in a study hall.
19.
What wireless network mode is being used when an office worker connects to a WLAN BSS from his desktop?
Correct Answer
A. Infrastructure
Explanation
When an office worker connects to a WLAN BSS from his desktop, the wireless network mode being used is infrastructure mode. Infrastructure mode refers to a network setup where wireless devices connect to a central access point or router. In this mode, the access point acts as a bridge between the wireless devices and the wired network, allowing the office worker to access resources and services within the network.
20.
What type of base station is associated with ad-hoc and peer-to-peer wireless networking?
Correct Answer
A. IBSS
Explanation
IBSS stands for Independent Basic Service Set, which is a type of base station associated with ad-hoc and peer-to-peer wireless networking. In an IBSS network, devices can communicate directly with each other without the need for a centralized access point. This allows for a decentralized and self-configuring network, making it suitable for scenarios where there is no existing infrastructure or when devices need to establish direct connections with each other.
21.
When an access point is used to link a wireless network to a wired Ethernet network, the access is considered to be a:
Correct Answer
A. BSS
Explanation
When an access point is used to link a wireless network to a wired Ethernet network, the access is considered to be a BSS (Basic Service Set). A BSS is a basic building block of a wireless LAN and consists of one access point and one or more wireless devices connected to it. In this scenario, the access point acts as a central hub, connecting the wireless devices to the wired network, allowing them to communicate and access resources on the Ethernet network.
22.
In an ad-hoc mode, each of the nodes must have the capability to relay network signals from one node to another, creating a __________ network as needed)
Correct Answer
A. Peer-to-peer
Explanation
In an ad-hoc mode, each node must have the capability to relay network signals from one node to another, creating a peer-to-peer network as needed. This means that all nodes in the network have equal capabilities and can directly communicate with each other without the need for a centralized server or infrastructure. This allows for a decentralized and flexible network where each node can act as both a client and a server.
23.
One of the following is developing MANET standards for use in Internet access.
Correct Answer
A. IETF
Explanation
The Internet Engineering Task Force (IETF) is responsible for developing and promoting standards for internet protocols and technologies. As MANET (Mobile Ad hoc Network) is a type of network that does not rely on any fixed infrastructure, it requires specific standards for its implementation in internet access. Therefore, it is logical that the IETF would be involved in developing MANET standards for use in internet access.
24.
Which one of the following is the topology of an infrastructure WLAN?
Correct Answer
A. Star
Explanation
The correct answer is Star. In an infrastructure WLAN, all devices connect to a central access point (AP) which acts as a hub. The AP manages the wireless network and controls the flow of data between devices. This topology resembles a star, where the AP is at the center and the devices are connected to it. This allows for efficient communication and easy scalability as new devices can be added without disrupting the network.
25.
__________ mode devices are able to connect to each other whenever they are within each other's range as long as they agree to a few basic link parameters.
Correct Answer
A. IBSS
Explanation
IBSS stands for Independent Basic Service Set. In IBSS mode, devices are able to connect to each other whenever they are within each other's range as long as they agree to a few basic link parameters. This mode is commonly used in ad-hoc wireless networks where devices communicate directly with each other without the need for a central access point.
26.
Which one of the following is not a primary factor on how well a moving connection can remain linked to a WLAN?
Correct Answer
A. Peer-to-peer
Explanation
The primary factors that determine how well a moving connection can remain linked to a WLAN are 802.11 roaming, roaming configuration, and duration of the movement. Peer-to-peer is not a primary factor in this context as it refers to a direct connection between two devices without the involvement of a central network or access point.
27.
Which one of the following is not an example of a wireless PAN's cable replacement technology?
Correct Answer
A. Violettooth
Explanation
Violettooth is not an example of a wireless PAN's cable replacement technology. This is because Violettooth is not a recognized or commonly used technology for wireless communication. It is likely a made-up term or a misspelling of the well-known Bluetooth technology, which is commonly used for wireless communication in personal area networks (PANs). IrDA standard, ZigBee, and Bluetooth are all examples of wireless PAN's cable replacement technologies that are widely used and recognized in the industry.
28.
Which one of the following network medium is not used?
Correct Answer
A. Platinum wire
Explanation
Platinum wire is not commonly used as a network medium. It is expensive and has limited applications in specific industries such as research and high-temperature environments. Copper wire, RF signals, and fiber-optic cables are widely used network mediums for transmitting data and signals in various communication systems.
29.
What is one of the two general types of spread-spectrum modulation?
Correct Answer
A. FHSS
Explanation
FHSS stands for Frequency-Hopping Spread Spectrum, which is one of the two general types of spread-spectrum modulation. In FHSS, the carrier frequency is rapidly switched between different frequencies within a wideband spectrum. This technique helps to spread the transmitted signal over a larger bandwidth, making it more resistant to interference and jamming. By hopping between frequencies, FHSS provides increased security and reliability for wireless communication systems.
30.
What signal transmission method intersperses message segments from multiple sessions into a single medium?
Correct Answer
A. Multiplexing
Explanation
Multiplexing is the correct answer because it is a signal transmission method that combines multiple data streams from different sources and sends them over a single communication channel or medium. It allows for the efficient use of bandwidth by dividing the channel into smaller subchannels, each carrying a different data stream. This technique is commonly used in telecommunications to transmit multiple signals simultaneously, such as in cable television or internet connections, where different channels or data streams are combined and transmitted over a single cable or line.
31.
What is propagated through the air and received by an antenna to transmit data signals?
Correct Answer
A. Radio waves
Explanation
Radio waves are electromagnetic waves that are propagated through the air and can be received by an antenna to transmit data signals. They are commonly used in various communication systems, including radio and television broadcasting, wireless networks, and satellite communications. Radio waves have the ability to carry information over long distances and are essential for wireless communication technologies.
32.
Which of the RF multiplexing methods uses times slices to carry multiple data streams on a single carrier?
Correct Answer
A. TDM
Explanation
TDM, or Time Division Multiplexing, is a method of RF multiplexing that uses time slices to carry multiple data streams on a single carrier. In TDM, each data stream is given a specific time slot during which it can transmit its data. This allows multiple data streams to share the same carrier frequency without interfering with each other. By dividing the time into slices, TDM ensures that each data stream gets its turn to transmit, providing efficient utilization of the carrier frequency.
33.
Which of the following is not an example of electromagnetic radiation using waveform?
Correct Answer
A. Audio
Explanation
Audio is not an example of electromagnetic radiation using waveform because audio refers to sound waves, which are mechanical waves that require a medium to travel through, such as air or water. Electromagnetic radiation, on the other hand, does not require a medium and can travel through a vacuum. Radio waves, gamma rays, and ultraviolet light are all examples of electromagnetic radiation.
34.
The general rule of __________ is the inverse-square law, which measures an electromagnetic wave's strength relative to the distance over which it is transmitted.
Correct Answer
A. Propagation
Explanation
The general rule of propagation is the inverse-square law, which states that the strength of an electromagnetic wave decreases as the distance over which it is transmitted increases. This means that the intensity of the wave diminishes as it travels further away from its source. Therefore, propagation is the correct answer as it refers to the way in which the wave spreads or travels through space.
35.
__________ measures how much ahead or behind a wave is to a reference frequency of the same wavelength.
Correct Answer
A. pHase
Explanation
Phase measures the relative position of a wave compared to a reference frequency of the same wavelength. It indicates how much ahead or behind the wave is in terms of its cycle. In other words, phase describes the timing or synchronization of a wave with respect to the reference frequency.
36.
Multipath propagation happens when a __________ cannot take a clear and direct path between a transmitter and a receiver.
Correct Answer
A. RF signal
Explanation
Multipath propagation occurs when an RF signal encounters obstacles or objects in its path, causing it to reflect, refract, or diffract. This results in multiple versions of the signal arriving at the receiver at different times and with different strengths. As a result, the direct path between the transmitter and receiver is obstructed, and the RF signal cannot take a clear and direct path.
37.
The __________ is designed to radiate the aura of the electromagnetic field created by the electric current.
Correct Answer
A. Antenna
Explanation
An antenna is a device that is specifically designed to radiate the aura of the electromagnetic field created by the electric current. It is used to transmit and receive electromagnetic waves, such as radio waves. The antenna acts as a conductor, converting the electrical signals into electromagnetic waves and vice versa. Therefore, the correct answer for this question is antenna.
38.
__________ is the method used to maximize the utilization of a limited transmission medium by interspersing message segments from multiple sessions onto the single medium.
Correct Answer
A. Multiplexing
Explanation
Multiplexing is the method used to maximize the utilization of a limited transmission medium by interspersing message segments from multiple sessions onto the single medium. This technique allows multiple signals to be combined and transmitted simultaneously, increasing the efficiency of the transmission medium. It is commonly used in telecommunications and computer networks to optimize the use of bandwidth and improve overall system performance.
39.
Cable TV using co-axial cable is a common application of __________ multiplexing transmissions.
Correct Answer
A. Frequency-division
Explanation
Cable TV using co-axial cable is a common application of frequency-division multiplexing transmissions. This means that different channels are allocated different frequency ranges to transmit their signals simultaneously over the same cable. Each channel is assigned a specific frequency band, and by using frequency-division multiplexing, multiple channels can be transmitted and received without interfering with each other.
40.
__________ switching is most commonly used in systems that require 'real-time' communications, such as voice and live media transmissions.
Correct Answer
A. Circuit
Explanation
Circuit switching is most commonly used in systems that require 'real-time' communications, such as voice and live media transmissions. In circuit switching, a dedicated communication path is established between the sender and receiver before the transmission begins. This ensures a continuous and uninterrupted connection, which is crucial for real-time applications where delay or loss of data is not acceptable. Unlike packet switching, which breaks data into small packets and sends them individually, circuit switching guarantees a fixed bandwidth for the entire duration of the transmission, making it ideal for time-sensitive applications.
41.
This spread-spectrum signal structuring technique uses amplitude modulation to combine the waveforms of the data and carrier signals.
Correct Answer
A. Direct-sequence
Explanation
Direct-sequence spread-spectrum is a technique that combines the data and carrier signals by using amplitude modulation. In this technique, the data signal is multiplied with a higher frequency carrier signal, resulting in a spread spectrum signal. This spread spectrum signal helps in improving the signal quality and security of the transmission by spreading the signal energy over a wider bandwidth. Hence, the correct answer is direct-sequence.
42.
A __________ infrared transmission must have a clear, unobstructed transmission path between the transmitter and receiver.
Correct Answer
A. Directed
Explanation
A directed infrared transmission refers to a specific type of infrared transmission where the signal is directed in a specific path between the transmitter and receiver. This means that there should be a clear and unobstructed transmission path for the signal to be successfully transmitted and received. In other words, the signal cannot be scattered or diffused in different directions, but rather it needs to be focused and directed towards the intended receiver.
43.
The radio communication spectrum is divided into bands based on ______.
Correct Answer
A. Frequency
Explanation
The radio communication spectrum is divided into bands based on frequency. Frequency refers to the number of cycles per second that a radio wave completes. Different frequencies are used for different purposes, such as AM and FM radio, television broadcasting, and mobile communication. Dividing the spectrum into bands based on frequency allows for efficient and organized use of the available radio frequencies, preventing interference between different types of communication.
44.
Microwaves use ________ propagation
Correct Answer
A. Line-of-sight
Explanation
Microwaves use line-of-sight propagation because they require a clear and unobstructed path between the transmitter and the receiver. This means that the microwave signals travel in a straight line and cannot bend or go around obstacles such as buildings or mountains. Line-of-sight propagation is commonly used in microwave communication systems to ensure reliable transmission of signals over short to medium distances.
45.
Multiplying the frequency of an electromagnetic wave travelling through air by its wavelength will always yield _________.
Correct Answer
A. The speed of light
Explanation
When an electromagnetic wave travels through a medium, its frequency and wavelength are related by the equation: speed = frequency x wavelength. Since the speed of light is a constant in a vacuum or air, multiplying the frequency by its wavelength will always result in the speed of light. Therefore, the correct answer is "the speed of light".
46.
High-frequency radio waves use ________ propagation
Correct Answer
A. Sky
Explanation
High-frequency radio waves use sky propagation. This means that they are transmitted through the Earth's atmosphere and are reflected or refracted by the different layers of the atmosphere. This allows the radio waves to travel long distances, even beyond the horizon, by bouncing off the ionosphere. Sky propagation is commonly used in long-distance communication and is particularly effective for high-frequency radio waves.
47.
Radio communication frequencies range from ___________.
Correct Answer
A. 3 KHz to 300 GHz
Explanation
Radio communication frequencies range from 3 KHz to 300 GHz. This range encompasses a wide spectrum of frequencies that are used for various types of radio communication, including AM and FM radio, television broadcasting, mobile phones, Wi-Fi, and satellite communication. The lower frequencies in the kilohertz range are typically used for long-distance communication, while the higher frequencies in the gigahertz range are used for shorter-range communication and data transmission. This broad frequency range allows for efficient and reliable communication across different applications and distances.
48.
Which of the following wireless transmission phenomenon cause ISI?
Correct Answer
A. Multipath propagation
Explanation
Multipath propagation refers to the phenomenon where wireless signals travel through multiple paths and reach the receiver at different times. This causes the signals to interfere with each other and results in intersymbol interference (ISI). ISI occurs when the delayed versions of the signal overlap with the current symbol, leading to errors in data transmission. Therefore, multipath propagation is the correct answer as it causes ISI in wireless transmission.
49.
What is the modulation method used with 802.11a PHY?
Correct Answer
A. OFDM
Explanation
OFDM (Orthogonal Frequency Division Multiplexing) is the modulation method used with 802.11a PHY (Physical Layer) in Wi-Fi networks. OFDM divides the available frequency spectrum into multiple subcarriers that are orthogonal to each other, allowing for efficient transmission of data. This modulation method is particularly effective in dealing with multipath interference and provides high data rates and robustness in wireless communication.
50.
On which 802.11x topology are frames forwarded between access points within the same network?
Correct Answer
A. ESS
Explanation
In the 802.11x standard, frames are forwarded between access points within the same network in an Extended Service Set (ESS) topology. ESS is a network configuration where multiple access points are connected to create a larger coverage area. This allows devices to seamlessly roam between access points while maintaining connectivity to the same network. Frames are forwarded between access points in an ESS to ensure continuous and uninterrupted communication for devices within the network.