Question

Explain the 802.11 standard and tell me about LTE 4G vs 5G. Why should we care about 5G? What will it DO for us? How will we use it? What role are the Chinese playing in 5G?

Answer 1

There are several specifications in the 802.11 family:

• 802.11 — applies to wireless LANs and provides 1 or 2 Mbps transmission in the 2.4 GHz band using either frequency hopping spread spectrum (FHSS) or direct sequence spread spectrum (DSSS).
• 802.11a — an extension to 802.11 that applies to wireless LANs and provides up to 54-Mbps in the 5GHz band. 802.11a uses an orthogonal frequency division multiplexing encoding scheme rather than FHSS or DSSS.
• 802.11b (also referred to as 802.11 High Rate or Wi-Fi) — an extension to 802.11 that applies to wireless LANS and provides 11 Mbps transmission (with a fallback to 5.5, 2 and 1-Mbps) in the 2.4 GHz band. 802.11b uses only DSSS. 802.11b was a 1999 ratification to the original 802.11 standard, allowing wireless functionality comparable to Ethernet.
• 802.11e — a wireless draft standard that defines the Quality of Service (QoS) support for LANs, and is an enhancement to the 802.11a and 802.11b wireless LAN (WLAN) specifications. 802.11e adds QoS features and multimedia support to the existing IEEE 802.11b and IEEE 802.11a wireless standards, while maintaining full backward compatibility with these standards.
• 802.11g — applies to wireless LANs and is used for transmission over short distances at up to 54-Mbps in the 2.4 GHz bands.
• 802.11n — 802.11n builds upon previous 802.11 standards by adding multiple-input multiple-output(MIMO). The additional transmitter and receiver antennas allow for increased data throughput through spatial multiplexing and increased range by exploiting the spatial diversity through coding schemes like Alamouti coding. The real speed would be 100 Mbit/s (even 250 Mbit/s in PHY level), and so up to 4-5 times faster than 802.11g.
• 802.11ac — 802.11ac builds upon previous 802.11 standards, particularly the 802.11n standard, to deliver data rates of 433Mbps per spatial stream, or 1.3Gbps in a three-antenna (three stream) design. The 802.11ac specification operates only in the 5 GHz frequency range and features support for wider channels (80MHz and 160MHz) and beamforming capabilities by default to help achieve its higher wireless speeds.
• 802.11ac Wave 2 — 802.11ac Wave 2 is an update for the original 802.11ac spec that uses MU-MIMOtechnology and other advancements to help increase theoretical maximum wireless speeds for the spec to 6.93 Gbps.
• 802.11ad — 802.11ad is a wireless specification under development that will operate in the 60GHz frequency band and offer much higher transfer rates than previous 802.11 specs, with a theoretical maximum transfer rate of up to 7Gbps (Gigabits per second).
• 802.11ah— Also known as Wi-Fi HaLow, 802.11ah is the first Wi-Fi specification to operate in frequency bands below one gigahertz (900 MHz), and it has a range of nearly twice that of other Wi-Fi technologies. It's also able to penetrate walls and other barriers considerably better than previous Wi-Fi standards.
• 802.11r - 802.11r, also called Fast Basic Service Set (BSS) Transition, supports VoWi-Fi handoff between access points to enable VoIP roaming on a Wi-Fi network with 802.1X authentication.
• 802.1X — Not to be confused with 802.11x (which is the term used to describe the family of 802.11 standards) 802.1X is an IEEE standard for port-based Network Access Control that allows network administrators to restricted use of IEEE 802 LAN service access points to secure communication between authenticated and authorized devices.

LTE 4G vs 5G

5G uses new and so far rarely used radio millimeter bands in the 30 GHz to 300 GHz range. Current 4G networks operate on frequencies below 6GHz.

Low latency is one of 5G's most important attributes, making the technology highly suitable for critical applications that require rapid responsiveness, such as remote vehicle control. 5G networks are capable of latency rates of under a millisecond in ideal conditions. 4G latency varies from carrier to carrier and cell to cell. Still, on the whole, 5G is estimated to be 60 to 120 times faster than average 4G latencies.

Over time, 5G is expected to advance wireless networking by bringing fiber-like speeds and extremely low latency capabilities to almost any location. In terms of peak speed, 5G is approximately 20 times faster than 4G. The new technology also offers a minimum peak download speed of 20 Gb/s (while 4G pokes along at only 1 Gb/s). Generally speaking, fixed site users, such as offices and homes, will experience somewhat higher speeds than mobile users.

Why should we care about 5G

Faster speeds

5G touts the delivery and downloading of data much, much faster, which is a feature that shouldn’t come as a surprise to anybody. A new generation of wireless without faster speeds would be like a new music technology that doesn’t profess clearer and more dynamic sound. Speeds for 5G are supposed to be over ten times (10x) that of 4G, or around 1 Gbps.

Latency

Latency, or the time it takes to move data from device to device, will be greatly reduced with the introduction of 5G. While 4G might be fitting the bill for your current needs, lower latency will prove critically beneficial, even lifesaving, for certain applications, such as surgery or the need for real-time data delivery to and from connected cars.

IoT

Faster speeds, lower latency…both can be chalked up to the need for each in the IoT world. In the next four (4) years, the number of IoT devices in use today (17 billion) will double, and with that precipitous growth comes the need for more cells to pick up and transmit the data. With 5G, smaller amounts of data will be transmitted by lower frequencies, while larger, bandwidth-hogging amounts will occur at higher ones. These multiple frequencies will require service providers to deploy smaller, but densely packed, cells on existing towers. These cells will determine the type of data, and its resultant frequency, that needs to be transmitted.

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