10 Mobile Connectivity and Application Support Flashcards
Third Generation (3G)
The Global System for Mobile Communications (GSM) and code-division multiple access (CDMA), which was developed by Qualcomm and available only in the United States it was much faster than GSM. Both were third generation (3G) mobile technologies. GSM and CDMA were not compatible with each other. Whatever technology you got was based on the provider you signed up with. Sprint and Verizon used CDMA, and AT&T and T-Mobile used GSM.
Fourth Generation (4G)
4G is designed to use IP instead of traditional telephone circuits, like 3G did. It’s designed to provide mobile broadband access. In the early days of 4G, there were two competing standards—WiMAX and Long-Term Evolution (LTE). WiMAX initially had higher speeds, but cell phone providers got behind LTE, which won out. The biggest enhancement of 4G LTE over 3G is speed. Some 4G LTE networks claim to give you download speeds of 10–20 Mbps and upload speeds of 3–10 Mbps. (The theoretical maximum for LTE is 300 Mbps download and 75 Mbps upload.) The range of 4G LTE depends on the tower and obstructions in the way. The optimal cell size is about 3.1 miles (5 km) in rural areas, and you can get reasonable performance for about 19 miles (30 km).
Fifth Generation (5G)
Some users will be able to get sustained wireless speeds in excess of 1 Gbps. The theoretical maximum peak download capacity is 20 Gbps.
There are three 5G classifications:
Enhanced Mobile Broadband (eMBB), which is for cell phone and mobile communication
Ultra-Reliable Low-Latency Communications (URLLC) for autonomous vehicles and industrial applications
Massive Machine Type Communications (mMTC) for sensors, which is designed to support IoT devices
The early focus was on developing eMBB infrastructure and mobile devices. Two versions of eMBB are available: fixed wireless broadband in densely populated areas and LTE for everywhere else. 5G LTE is like 4G LTE but about seven to ten times faster. Browsing speeds for 5G are about 490 Mbps on average, and most users can get 100 Mbps downloads. 5G uses existing LTE frequencies in the 600 MHz to 6 GHz range. eMBB fixed wireless is revolutionary, offering gigabit speeds using millimeter wave (mmWave) technology in the 24 GHz to 86 GHz range. mmWave is limited to about half a mile and is easily blocked by obstructions.
What is Tethering ?
Tethering is when you have connected a device to a mobile hotspot. Some devices will not function as a mobile hotspot but will allow you to tether a laptop (or other device) to it so that the mobile device can share the cellular Internet connection.
What are real-time operating systems (RTOSs) ?
Specialized OSs that handle specific functions for the device. These two OSs are very small and they are referred to as real-time operating systems (RTOSs). They are designed to be lightweight and fast, and “real-time” refers to their ability to minimize lag in data transfers.
First, there is a baseband OS that manages all wireless communication, which is handled by a separate processor. A radio firmware update, or a modem update two terms are interchangeable with baseband update, which simply means an update of the baseband OS.
A subscriber identity module (SIM) OS manages all data transfers between the phone and the SIM chip, which is a small memory chip that stores user account information, phone identification, and security data, and it is generally tied to a specific carrier.
These RTOSs are normally updated when a user updates an operating system, but occasionally the carrier will update them when the phone is not otherwise busy. Users or companies can provide newer versions of the baseband RTOS, and others can download and install them.
Preferred Roaming List (PRL) updates
The PRL is the reference guide the phone uses to connect to the proper cell phone tower when roaming. Both PRI updates and PRL updates also normally happen when the primary OS on the phone is updated.
Product Release Instruction (PRI) updates
The PRI contains settings for configuration items on the device that are specific to the network that it’s on. Both PRI updates and PRL updates also normally happen when the primary OS on the phone is updated.
International Mobile Equipment Identity
The International Mobile Equipment Identity (IMEI) is a 15-digit serial number that is unique to each phone. If a phone is reported stolen, the IMEI will be declared invalid and the phone disabled. The IMEI can be displayed on most phones by dialing *#06#.
Mobile Equipment Identifier
The mobile equipment identifier (MEID) is an alternate form of a serial number. It’s identical to the first 14 numbers of the IMEI.
International Mobile Subscriber Identity
The international mobile subscriber identity
(IMSI) is a unique 15-digit identifier that describes a specific mobile user and their network. It’s composed of the following three elements:
Mobile Country Code
The mobile country code (MCC) is a three-digit code, such as 310 for the United States and 234 for the United Kingdom.
Mobile Network Code
The mobile network code (MNC) is a two-or three digit code that identifies the carrier.
Mobile Station Identifier Number
The mobile station identifier number (MSIN) is a sequential serial number. Integrated Circuit Card Identifier The integrated circuit card identifier (ICCID) is a 19-or 20-digit identifier for each SIM chip globally. It’s like a serial number for the SIM card.
Secure Element Identifier
The secure element identifier (SEID) is a very long hexadecimal code that uniquely identifies the phone. It is used in security applications, NFC, and features like Apple Pay.
Global Positioning System (GPS)
Global Positioning System (GPS) is a satellite-based navigation system that provides location and time services. There are three major component to GPS:
the satellite constellation
the ground control network
the receiver
What is The ground control network ?
The ground control network monitors satellite health and signal integrity.
What are Global Navigation Satellite Systems (GNSSs) ?
global satellite-based navigation systems managed by government entities.
Name Managed by Number of satellites
Global Positioning System (GPS)
United States 24
Global Navigation Satellite System (GLONASS) Russia 24
Galileo Positioning System
European Space Agency 30
BeiDou Navigation Satellite System (BDS) China 35
Indian Regional Navigation Satellite System
(IRNSS) India 7
Two levels of GPS service:
Standard Positioning Service (SPS) for civil use, accurate to within 100 meters horizontally and 156 meters vertically. Uses Coarse Acquisition (C/A) code.
Precise Positioning Service (PPS) for Department of Defense and ally use, accurate to within 22 meters horizontally and 27.7 meters vertically. Uses Precise (P) code.
The two service levels are separated by transmitting on different frequencies, named L1 and L2.
L1 transmits at 1,575.42 MHz, and it contains unencrypted civilian C/A code as well as military P code.
L2 (1,227.60 MHz) only transmits encrypted P code, referred to as Y code. In the United States, SPS is free to use; the receiver just needs to manage C/A code. PPS requires special permission from the U.S. DoD as well as special equipment that can receive P and Y code and decrypt Y code.
Mobile Location Services
Instead of using satellites, it uses cell phone towers for its triangulation points. Cellular location services is less precise than GPS. Cellular location services is only accurate within about 1,000 meters. If a user’s phone is within range of multiple cell towers, that precision can increase substantially and get close to GPS performance. Mobile devices use a combination of GPS, cellular and Wi-Fi signals for location purposes.
