Wireless Exam Stuff
How does the advantage of connection density in 5G compare to 4G?
As the IoT market accelerates, many more devices will be connected to cells. 5G allows up to 900,000 more devices to be connected per square kilometer than 4G, which supports the connection of at most 100,000 devices per square kilometer.
What is one problem MD2D technology is facing right now, and what would it improve if it could be done??
Changing from Sender-driven to Receiver-driven networks, which would allow for the system to become more efficient with its use of bandwidth, increasing data rates.
Why Femtocells were not made in 1999-2000?
Concept of compact self-optimizing cellsite was defined, but proven to be too highly costly to be commercially available
If LTE is unavailable in a certain area, explain how a user may still be able to transmit and receive voice traffic?
Due to LTE's Voice of Internet Protocol (VOIP), the user is able to fall back to previous generations (2G/3G) if that is the service provided in the area.
What is LTE and what does it stand for?
LTE stands for long-term evolution and allows for the improved speeds of data transfers between devices along networks
What is it called when a device has little to no setup requirements?
Plug and Play
List three types of small cells used for 5G base stations?
The three cell types of small cells are femto, pico, and micro.
Approximately how many fibers will 5G small cell sites require?
They will require about between two and twelve fibers per small cell site.
What are the benefits of using multiple antennas in LTE?
Using multiple antennas provides additional protection to the radio channel fading by allowing for spatial diversity. Multiple antennas can also shape the radiation patterns in transmission and reception to increase gain in specific directions and cancel interference
By 2025, how many IoT devices are going to be connected and how much data is going to be transmitted?
By 2025, there are going to be 22 billion devices connected to the network and generate 79.4 zettabytes of data by those devices.
How does multi-hop communication extend the coverage.
By allowing users to use other devices as relays to link to the base station.
How would 5G change the cell architecture?
Dense small cells will be needed due to the short propagation ranges at millimeter wave. Spectral efficiency: more optimal use of multiple frequencies so that greater bandwidth may be extended. Energy efficiency: leveraging technological gains for both transmitters and servers. Utilization.
Where would you suggest someone implement femtocells?
Femtocells should be used indoors, where devices can connect to femtocells rather than the primary cell network.
How did LTE manage power consumption in the uplink, compared to the downlink?
In the uplink, LTE used SC-FDMA. SC-FMDA is a much more power efficient alternative to OFDMA that comes with some disadvantages. Regardless, it can still utilize some of the key advantages needed from OFDMA. On the other hand, OFDMA has significant variations of power in output signals. They have to use linear amplifiers, which provide lower efficiency.
Name at least two advantages to femtocells.
● Increased indoor cell reception ● Decreased mobile cellular device power requirements ● Transmission power can vary in reply to demand
Name at least two disadvantages to femtocells
● Limited range ● Risk of interference with other femtocells
What is the significance of years 2015-2017 for Femtocells?
● T-Mobile began deployment of of 4G LTE Femtocells ● It is estimated there would be 28 million units of femtocells produced.
Why is D2D capable of having low latency?(
The communication range between user devices is short.
How would IoT affect new smart cities?
The devices can be used to optimize traffic lights, help with waste management, and allow for quicker responses in emergency situations.
How can device impersonation be used maliciously?
The impersonator device can send malicious packets to the device requesting data instead of the data requested.
Why is the rise of the Internet of Things a security risk?
The rise of IoT increased vulnerability due to increased numbers of compromisable entrances due to the larger number of connected devices.
What did students at Carnegie Mellon University create in 1982?
The students at Carnegie Mellon University created an ARPANET controlled coke machine in 1982.
What are benefits FMC services?
The use of both fixed and cellular features and "seamless" transition between the two network types.
Why was LTE chosen as a standard for 4G network services?
This was because LTE was able to utilize existing infrastructure from previous carriers instead of building and designing a system from the ground up
How does LTE Work?
When a mobile device is connected to the LTE network it transmits and receives signals from and to a cell tower which transmits the data requested by the user to a data center. The data center is connected to the internet and fulfils the needs of the users request then sends back the data.
What are the main characteristics of the serving gateway (SGW) in 4G LTE?
Routes and forwards user data packets, acts as the mobility anchor for the user plane during inter-eNB handover between LTE and other 3GPP and lower.
What are any three security requirements of D2D communication?
Secure routing and transmission of data, authentication of valid users, and data transmission with message integrity
What is Self-Interference?
Self-interference is the phenomena where a receiver's performance is degraded by unrelated emissions at the same or similar frequency to the desired signal, This is unwanted energy which is billions of times (100 dB+) stronger than the desired receive signal thus degrading the signal to noise ratio (SNR)
Why Femtocells were a success?
1. The broadband Internet connection provided by the customer at no cost to the cellular operator. 2. Transmit power levels are very low, as the femtocell is designed to cover just a few hundred square feet.
What is the effective range of Femtocells?
10-40 Meters
What is the difference in 5G technologies that makes customers interested?
5G technologies bring new radio air interface design and 5G NextGen core network. 5G new radio introduce many wireless inventions, the top wire inventions are listed below. a. Advanced, flexible LDPC channel coding b. Advanced massive MIMO antenna technologies c. Advance spectrum sharing techniques
What potential speeds will Full Duplex technology allow us to achieve in 5G?
A Full-Duplex device is capable of bi-directional network data transmissions at the same time aka simultaneously increasing spectrum efficiency and speed, this will allow us to achieve up to 20 Gbps UL and DL speeds simultaneously over a single channel
Where this term, "Femto Access Point", comes from
A broader term which is more widespread in the industry is small cell, with femtocell as a subset, which is also called FAP.
In what way are you able of achieving reduced delay in D2D communication?
Since D2D means communication between devices is much shorter, the reduced pathways means reduced latency.
How is D2D used in emergency communications?
Ad-hoc networks can be created for wireless communications when the base station is damaged or power lines are down.
How could D2D technologies benefit and aid already existing base stations?
Can help offload traffic from congested base stations.
What is different between Device to Device communication versus normal technologies when it comes to sharing data?
Device to Device communication ensures a connection between the two devices that wish to share information (peer-to-peer), which allows for communication without the need of an access point.
What is the primary use of D2D LTE and why?
Emergency service communication, because the D2D bypasses the base station, causing the communication to be instant, more reliable, and have less of a chance of interference. They become similar to a walkie-talkie.
What are the main usage scenarios of 5G?
Enhanced Mobile Broadband (eMBB) to deal with hugely increased data rates, high user density and very high traffic capacity for hotspot scenarios as well as seamless coverage and high mobility scenarios with still improved used data rates Massive Machine-type Communications (mMTC) for the IoT, requiring low power consumption and low data rates for very large numbers of connected devices Ultra-reliable and Low Latency Communications (URLLC) to cater for safety-critical and mission critical applications
What are the benefits of 5G development?
Faster speed: increase of data transfer speed, significantly faster transmission of image and videos. Shorter delays: reduce latency. Increased connectivity: more people and more devices communicate at the same time.
What type of advancements will the evolution of 4G LTE bring?
Higher mobile broadband speeds, better live broadcasting coverage, and many useful mission-critical applications such as: health monitors and connected alarm systems
In a 5G wireless usage, explain VR and AR?
Higher resolution, higher frame rate. Stereoscopic, dynamic range (HDR), 360* spherical content, 6DoF.
What does the eNB (e node base station) host in 4G LTE systems and what does it offer?
Hosts Physical, Medium Access Control, Radio Link Control, and Packet Data Control Protocol. It offers Radio Resource Control functionality that corresponds to the control panel.
What are the main advantages to Device-to-Device Communication?
Improved spectral efficiency, reduction in power consumption, and reduced cost per bit, reduced interference and higher transmission rates.
Why is a 5G Communication System preferred over a 4G Communication System?
In terms of speed 5G communication system is able to provide up to 100 gigabits per second which is 100 times faster than 4G communication system. As we talked about latency the 4G has very high latency compare to 5G. 5G Communication System will also able to fix the bandwidth issue with emerging technology such as driverless cares and connected home products.
Explain two disadvantages of IoT.
IoT is not always reliable and has security concerns. IoT is always on and is connected to different networks. However in this day and age, we are not at peak dependability for these services especially when it comes to serious affairs such as the military. There are also security concerns with IoT, they are easily hacked and data from the cloud is stolen.
How is IoT utilized in farming and poultry?
IoT monitoring is used in the industry to get data about the health of the animals, so that way the farmers can quickly find a sick animal and pull them away from the others.
What advantages/services does the Domain Naming Service (DNS) provide?
It improves the selection process because it can accept various criteria as inputs while also making inter-operator operations more flexible. It can also store information on mapping, and provide information on collocated nodes geographical proximity between different nodes.
The difference of femtocell comparing with Wi-Fi cordless
It uses 2.4 GHz signals and voice over IP (VoIP), independent of the cellular network.
What year did LG announced its IoT based refrigerator?
LG announced its Internet of Things refrigerator in 2000.
What does LTE and NFC stand for and what are their general descriptions?
LTE stands for Long-Term Evolution and NFC stands for Near Field Communication. LTE increases the capacity and speed using a different radio interface together with core network improvements, and NFC is a set of communication that enable two electronic devices to establish communication by bringing them within 4 cm (11⁄2 in) of each other.
What role does Mobility Management Entity (MME) play in LTE?
MME is responsible for idle mode user equipment tracking and paging procedures including retransmissions. It also in charge of generating and allocating temporary identities to user equipment.
Who is primarily impacted by the Internet of Things?
Many people were impacted by IoT. The main people who were impact were everyone with "smart" devices, from homeowners to major corporations.
Where is the future of IoT headed?
More devices are going to be connected to the internet. There is going to be an increase in "smarter" devices that will be used in homes, businesses, medicine, and other fields.
What kind of infrastructure and range do most D2D systems have?
Most D2D systems don't rely on infrastructure to function, but instead use it to help better their communications in short range
Name 3 other benefits of D2D
Network efficiency increase, less power requirement results in longer battery life, connection still establish during absence of network, public safety and security, extends network without the complications of base station hardware
What is network slicing and how will it help 4G LTE?
Network slices are logical networks that are overlaid on a physical infrastructure, which represents a smart way to build separate logical networks for different services.
Does D2D communication work when all users are "free-ride" users? Why or why not?
No, the flow of information breaks down because no data communication is flowing between any device
What technologies are included in LTE?
OFDM(Orthogonal Frequency Division multiplex), MIMO(Multiple Input Multiple Output), SAE (System Architecture Evolution)
What was the key difference between previous uses of OFDMA and LTE's use of OFDMA, and how did it benefit LTE?
Previous carriers that used OFDMA were only able to allocate users in the time domain. With LTE, carriers were able to allocate users in the time and frequency domain.
How does the network energy efficiency of 5G compare to 4G?
The 5G network will be 100 times more energy efficient than 4G. So even as the number of wireless devices increases, the energy required to power them will decline. This means the carbon footprint of wireless communication networks globally will also decline or at least not increase proportionate to the number of devices increases.
What is the Internet of Things (IoT)?
The Internet of Things (IoT) is a system of interrelated computing devices, machines, objects, animals or people that are provided with unique identifiers and the ability totransfer data over a network without requiring human-to-human or human-to-computer interaction.
What is the current and the possible future communication system for wireless vehicular communication?
The current wireless communication for vehicles is Dedicated short range communications, while the possible future vehicular communication is C-V2X communication.
What is the frequency range for millimeter waves?
The frequency range for millimeter waves is 30 GHz to 300 GHz.
What is the goal of Authentication and Key Agreement (AKA)?
The goal of AKA is to establish mutual authentication between the User Equipment (UE) and the LTE network as well as to derive a common session key.
Why is the IoT significant?
The significance of IoT is that it allows businesses and consumers to operate with higher efficiency. As the IoT continues to grow it will allow more information to be collected around the world, resulting in users with a better understanding of how to react and adapt to the changing environment around them.
Why were femtocells originally seen as cost-prohibitive?
They required many small-scale devices capable of transmitting on cellular frequencies. Silicon and computer chips had not matured to the point where this was possible given equipment on the market.
Explain two advantages of IoT?
Two advantages of IoT is that it increases the number of remote services that we can perform. We can remotely control computers and find our iPhones. It also increases communication. It is easier to transfer data packets over an interconnected network.
List two privacy concerns regarding IoT
Two privacy concerns regarding IoT are that hackers can gain access to private information and another would be the misuse of personal information which can lead to identity theft.
What did Black Hat Hacker Conference demonstrate?
Usage of Verizon Femtocell to intercept voice calls, data, and SMS of any handset that connects to device
According to Cisco, what takes up the most internet traffic?
With more portable devices being made, videos take up the most internet traffic with predicted increase of 71% by 2020.
Will small cells be required to implement 5G?
Yes, small cells will be required to implement 5G because this high frequency signal does not travel far. Therefore, lots of small cells are needed to increase the distance of 5G signals.
How could D2D be used to help driverless cars?
a. Allows drivers to send messages to cars next to them b. Allows cars to communicate with traffic lights at intersections c. Used with cellular networks to share data about other cars and location d. Use with satellites to communicate data about other cars and location
What are two of the improvements device to device can have when used in a cellular network?
a. Increases bandwidth for each user b. Extends cell coverage c. Increases energy efficiency d. Removes need for any time division
Why is the implementation of WLAN in vehicles significant?
a. It allows for vehicles to communicate with each other and cell towers to have more data on their environment. b. It gives the driver's phone a wireless access point for social media c. It allows automakers to implement their own media streaming platforms into the car d. It allows the Automaker to gather location data of the vehicle to sell for more profit
Why does aLTEr pose as a major issue in the security of LTE and what are possible solutions?
aLTEr redirects users to malicious servers to gain access to personal data from user's equipment. It was caused by shortcomings of design decisions during the development of LTE Possible solutions to this issue are to use websites that are HTTPS and DNS secured.
What benefits will 5G bring to the consumer?
· 99.999 availability · 100% coverage area (no dead spots) · 90% reduction in energy use · 1000+ improvement in bandwidth per area
What improvements in Radio Access Network has made IoT, Artificial Intelligent, Blockchain possible?
· Device to device communicaton · Network function virtualization(NFV)cloud based · Software defined networks(SDN)
What are the major ways to get more broadband?
· Increasing transmit power (or reducing noise), · Adding spectrum and · Reducing the number of users per cell.
What are the 3 main types of LTE signal modulation, and at what "bit per symbol" do each operate at?
• 4QAM - 2 bits per symbol • 16QAM - 4 bits per symbol • 64QAM - 6 bits per symbol
Do the downlink and uplink process in LTE utilize the same or different techniques and list the process/es below?
• Downlink - OFDMA (Orthogonal Frequency Division Multiplexing Access) • Uplink - SC-FDMA (Single Carrier OFDMA)
