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Abstract: It’s no secret that wireless communications standards continue to evolve to provide ever-increasing data throughput capabilities. Today, two of the hottest wireless standards are IEEE 802.11ac in wireless-local-area-network (WLAN) products and 3GPP LTE-Advanced in cellular communications. IEEE 802.11ac is the new draft standard for Gigabit WiFi. IEEE 802.11ac promises data rates of up to 1.73Gbps between an access point and a wireless client. In this paper, we’ll take a basic knowledge about IEEE 802.11ac. More specifically, we’ll look at how features such as Video Streaming and Data Syncing and Backing Up. Finally, we’ll look technical detail and its application.
I. INTRODUCTION
IEEE 802.11ac is the fifth generation in Wi-Fi networking standards and will bring fast, high quality video streaming and nearly instantaneous data syncing and backup to the notebooks, tablets, and mobile phones that have become our everyday companions. Improvements in transmission speeds will be dramatic. Entry-level IEEE 802.11ac products will provide a data rate of 433 Mbps (megabits per second), which is at least three times faster than that of the most common devices using the current wireless standard, which is IEEE 802.11n. Because the new standard gives manufacturers the flexibility to offer a range of products with different levels of performance, some high-speed IEEE 802.11ac devices will offer wireless transmission in excess of a Gigabit per second—remarkable speeds that put IEEE 802.11ac wireless networks ahead of most wired networks.
In addition, there will be dramatic improvements in wireless reliability, range, and coverage. Homes and apartments now plagued with “dead spots” will enjoy vastly improved reception. Faster file transfer also leads to longer battery life in mobile phones. Products based on IEEE 802.11ac will be fully backward compatible with current Wi-Fi devices. Older devices, however, won't be able to take advantage of the improved speeds offered by IEEE 802.11ac. Home networking products containing IEEE 802.11ac adapters are expected in Q3 2012. They will begin appearing in laptops and notebooks for the Christmas 2012 selling season. Mobile phones and tablets—bo th crucial Wi-Fi markets—are likely to ship with IEEE 802.11ac chips in 2013.
IEEE 802.11ac is the fifth generation of Wi-Fi to come along since Wi-Fi was introduced in 1997. The roll-out of new IEEE 802.11ac devices, like those of previous generations, is expected to take between one and three years, beginning first with home networking products and then working its way to other products as manufacturing costs decline. By 2015, virtually all new Wi-Fi products are expected to be based on IEEE 802.11ac technology, in the same way that nearly all Wi-Fi products on sale today are based on IEEE 802.11n, which is the current standard.
II. WHY IEEE 802.11AC?
Digital-content consumption is on a steep incline, with video content expected to reach approximately 90 percent of global consumer traffic, according to Cisco’s 2011 Visual Networking Index Forecast. At the same time, Internet traffic is shifting rapidly from wired to wireless networks. The increased reliance on wireless networks, the explosion of video consumption and the growing number of wireless devices being used are all putting tremendous stress on legacy 802.11a/b/g/n networks. As a result, consumers are prone to experience deteriorated performance, choppy videos and slower load times.
5G WiFi overcomes this digital content and wireless device challenge. With new innovations that allow for more reliable whole home coverage, 5G WiFi will allow consumers to stream digital content between devices faster, and simultaneously connect more wireless devices to home and enterprise networks, while conserving battery power[1].
Although there are many benefits of IEEE 802.11ac technology, it was developed with three main features in mind—video streaming, data syncing, and backup.
Video Streaming
PCs may have started out as “computers,” but increa singly, we are using our PCs—not to mention our mob ile phones and tablets—as convenient substitutes for TVs . Video entertainment has become one of the most popular use of electronic devices, so much so that video content from Netflix, Hulu, YouTube, and similar services now constitutes most of the Wi-Fi traffic. But video streaming requires a great deal of bandwidth, many times more than does music. And so, watching video over current Wi-Fi networks can be a frustrating experience. For example, it's common for the picture to freeze because the wireless network simply can't keep up. The problem becomes much worse the further you are from your Wi-Fi access point.
Data Syncing and Backing Up
Nearly everyone today makes daily use of multiple devices. The home computer remains the hub for most people, a central repository containing files for work, music, video, games, and more. But we take our mobiles phones with us as we go about our daily lives and need to keep our phones and computers in sync. Unfortunately, that has become a time consuming chore. Ask anyone who tries to download a playlist of music, a new batch of photos, or some recently changed calendar appointments onto a mobile phone while dashing out the door in the morning.
With movies, it is even worse. Frequent travelers enjoy spending part of a plane ride catching up on the latest Hollywood release. But they often discover too late that they don't have time for a 20-minute movie transfer from PC to tablet before catching a cab for the airport. The high throughput rates of IEEE 802.11ac will slash all these sync times. You'll be able to put a phone or tablet next to your PC and sync your playlists and calendars in a few seconds. Entire movies can be transferred in minutes. With IEEE 802.11ac, quick, effortless background syncing will soon be as much a part of the mobile phone experience as texting or taking pictures is today.
The same is true for backing up our mobile devices, which is becoming an increasingly important task considering how much of our lives we carry around on them. Between calendar entries, text messages, photos, videos, and downloaded applications, losing the data contained on a mobile phone for most people would be as calamitous as losing everything on their computer hard drive. The speed of IEEE 802.11ac will take the hassle out of backing up mobile phones and tablets. Consumers can have peace of mind knowing that they will always have access to their phone data, even if the phone itself is no longer available.
III. ADVANTAGES OF IEEE 802.11AC
SPEED
Entry-level 5G WiFi products will be 450 megabits per second, which is at least three times faster than the most common devices using the current wireless system, 802.11n. And because the new standard gives manufacturers the flexibility to offer a range of products with different levels of performance, some high-speed 802.11ac devices will offer transmission in excess of a gigabit per second -- remarkable speeds that wired networks attained only recently
RELIABILITY
5G Wifi offers dramatic improvements in wireless reliability, range and coverage. Homes and apartments now plagued with "dead spots" will enjoy vastly improved reception. But because 802.11ac transmissions start out so much faster than those from earlier networks, you can be, say, 30 feet away from an 802.11ac access point and get the same data throughput that you would if you were 10 feet from an 802.11n transmitter. But 5G Wifi networks, with beam-forming and other innovations, do a much better job in penetrating all forms of building materials, including concrete than its predecessors.
IV. IEEE 802.11AC—THE TECHNICAL DETAILS
Computers, mobile phones, tablets, networking equipment, and other devices equipped with the new IEEE 802.11ac networking technology will experience connections between three and 10 times faster than is possible today. Wi-Fi coverage will experience less interference, extend to greater distances, and be spread out across a larger coverage area.
Here are some of the ways that IEEE 802.11ac achieves these benefits.
Spectrum Changes
You may not realize it, but every Wi-Fi device is, in fact, a small radio station, sending and receiving signals over a portion of the radio spectrum just like AM and FM broadcasters. The amount of available spectrum is limited by the laws of physics, and use that spectrum is strictly regulated by international agreements.
Most of today's IEEE 802.11n Wi-Fi devices operate in the 2.4 GHz frequency band. (A frequency band is a slice of the radio spectrum, and the number associated with it tells you where on the spectrum it is located, the same way that the frequencies of radio stations identify their place on the dial.) One problem with current Wi-Fi networks is that the 2.4 GHz band is crowded with many other devices, from baby monitors to Bluetooth headsets to microwave ovens. Because all of these devices are competing for the same limited bandwidth, everyone's Internet connection slows down, just as the traffic on a highway slows down when too many cars are on the road. By contrast, IEEE 802.11ac works exclusively in the much less crowded, or “cleaner,” 5 GHz spectrum. With less competiti on for the airwaves from other devices, transmission rates shoot up. But IEEE 802.11ac has one other extremely important bandwidth advantage over its predecessor standard: There is simply more room available for Wi-Fi in the 5 GHz band than there is in the2.4 GHz band. Each IEEE 802.11ac communications channel is as much as four times wider than the channels available in IEEE 802.11n. Just like a six-lane freeway can handle more cars than one with two lanes, the wider the available swath of bandwidth, the faster the Wi-Fi connections can operate[3].