In this video we will be discussing wireless networking protocols such as:Β 802.11a/b/g/n/ac wireless networks, frequencies, channels, MIMO, Bluetooth, NFC, RFID, Zigbee, Z-Wave, 3G, 4G, 5G, LTE.
WiFi Standards
The 5 WiFi standards:
Wireless Frequency Differences
Wireless routers can use either the 2.4GHz or the 5GHz frequency band and a lot of wireless routers offer both frequencies that can be configured separately. Some routers are even capable of switched between the two frequencies automatically if a signal becomes weak. Each has advantages & disadvantages such as:
Understanding MIMO (Multiple Input & Multiple Output)
MIMO is a method for multiplying the capacity of a radio link using multiple transmission and receiving antennas to exploit multipath propagation. MIMO has become an essential element of wireless communication standards including IEEE 802.11n & 802.11ac. Some smartphones and tablets simply use the term MIMO (multiple input multiple output) if they support two or more 802.11n or 802.11ac streams. MIMO devices are available in the following configurations:
The number of transmit antennas typically corresponds to the number of data streams (spatial streams) the device can support. In the case of a router that supports both 2.4GHz and 5GHz signals, the specifications include this information for each band. Devices that have different numbers of receiving antennas and sending antennas may be identified by the number of data streams it can send and receive. For example, a device with a 2×3 antenna configuration can also be identified as having a 2×3:2 configuration (two send antennas, three receive antennas, and send/receive support for two data streams).
Bluetooth
Bluetooth is a wireless technology standard used for exchanging data between fixed and mobile devices over short distances using short wavelength UHF (ultra high frequency) radio waves in the industrial, scientific & medical radio bands, from the 2.4GHz band, and building personal area networks (PANs). Bluetooth runs in virtually the same 2.4GHz frequency used by IEEE 802.11b, 802.11g, and 802.11n wireless networks but uses a spread-spectrum frequency-hopping signaling method to help minimize interference. Bluetooth can be used to do the following:
Bluetooth versions:
The most common Bluetooth devices are Class 2 devices such as printers, headsets, computer dongles, etc. To connect a Bluetooth device to a mobile device, Bluetooth needs to be enabled. Then the Bluetooth device needs to be synchronized (paired or linked) to the mobile device. Sometimes the synchronization process requires a PIN code. Once synchronized, the device needs to be connected. Finally, the Bluetooth connection should be tested.
Configuring a Bluetooth Headset on an Android-Based Device
Steps to connect a Bluetooth headset to a typical Android-based device:
To disconnect the device but retain the pairing, turn off the device. To unpair the device, tap the settings (gearbox) icon on the screen and tap Unpair. To use it again, pair it again.
Configuring a Bluetooth Headset on an iOS Device
Steps to connect a Bluetooth headset to a typical iOS device:
To remove the device, tap it. One the next screen, tap Forget This Device. To stop using the device but keep it paired, tap Disconnect. Be mindful that most Bluetooth devices can be connected to only one mobile device at a time.
NFC
Near-field communication is a set of communication protocols that enable 2 electronic devices, one of which is usually a portable device such as a smartphone, to establish communication by bringing them within 4 cm of each other. NFC enables smartphones to be used for payment services such as Apple Pay, Samsung Pay, and Android Pay. NFC also enables file transfer between supported devices. To transfer files between smartphones with NFC, both smartphones must have NFC enabled and an NFC file transfer utility (sometimes referred to as “tap and go”) enabled, such as S Beam (Samsung smartphones) or Android Beam (Android smartphones). Once that is enabled, simply tap the phones together to transfer files. NFC can also be used with compatible printers for tap-to-print capabilities.
RFID (Radio Frequency Identification)
RFID uses electromagnetic fields to automatically identify and track tags attached to objects. An RFID tag consists of a tiny radio transponder; a radio receiver and transmitter. When triggered by an electromagnetic interrogation pulse from a nearby RFID reader device, the tag transmits digital data, usually an identifying inventory number, back to the reader. This number can be used to inventory goods. There are two types:
Examples of RFID technology:
Zigbee and Z-Wave
Zigbee is a low-power, low data rate, and close proximity (PAN…personal area network) wireless ad hoc network. Zigbee is intended to be simpler and less expensive than other wireless PANs, such as Bluetooth or more general wireless networking such as WiFi. Applications include wireless light switches, home energy monitors, traffic management systems, and other consumer and industrial equipment that requires short-range low-rate wireless data transfer. Zigbee operates at the 2.4GHz frequency. Z-Wave is a more recent version of Zigbee that uses less power and operates on the much lower 908.42MHz frequency. Zigbee and Z-Wave are not interoperable.
3G, 4G, 5G, and LTE
3G, 4G, 5G, & LTE networks are provided from cell towers. The G stands for “generation” and each new generation of network service provides advanced signaling and available services. Most cell phones in use now support 3G, 4G, and LTE. 5G for the most part is still in the development & testing phase.