802.11AC Dual Band

    Dual-frequency refers to the 11AC router supports 5GHz and 2.4GHz two bands, their transmission speed is 5GHz 900Mbps, 2.4GHz of 400Mbps. General 5GHz Band interference is less, that is to say, although you use Unicom, but you can also get faster speed. The 11AC router supports both 5G and 2.4G two bands. One of the 5G bands can make your internet speed soar oh. Because the general routers now support the 2.4G band, and many home appliances are also in the 2.4G band, such as microwave ovens, such as other people's home routers. So the frequency band is very congested, and then the network can not run fast, like the park traffic jams. And 5G is like a newly repaired highway, with fewer people so the car is very small, so the speed can be quickly leverage. So when you use the 11AC router to surf the internet, it is forcefully, very carefree ~ ~

Since the last few weeks, the first 802.11AC wireless products have started to go public. In essence, the 802.11AC is the current smartphone and notebook computer mainstream 802.11n standard enhanced version, simply from the download speed can have a large increase, and even can reach the original 802.11n several times the speed.

How the 802.11AC works

802.11AC core technology is mainly based on 802.11a, continue to work in the 5.0GHz band to ensure backward compatibility, but the data transmission channel will be greatly expanded, on the basis of the current 20MHz to 40MHz or 80MHz, and may even reach 160MHz. Plus about 10% of the actual frequency modulation efficiency increases, the new standard of theoretical transmission speed is expected to reach 1Gbps, 802.11n 300Mbps is more than three times times.

In fact, the 802.11AC project began in the first half of 2008, when it was called "Very High Throughput" (very good throughput), the goal is to reach 1Gbps directly. By the second half of 2008, the project was divided into two parts, one 802.11ac, working under 6GHz, for medium to short distance wireless communication, Formally designated as the successor of 802.11N, the other is 802.11AD, working in 60GHz, the market positioning and UWB similar, mainly for home entertainment equipment. However, the 802.11AC standard did not even enter the draft stage. At that time, the new draft standard would be available by the end of 2011 and eventually be completed in November 2012. the difference between 802.11AC and 802.11n

From the core technology point of view, 802.11a C is built on the 802.11A wireless Wi-Fi standard, including the 802.11a 5GHz band will be used. However, in the channel settings, 802.11AC will continue to use the 802.11n MIMO (multi-input and multi-out) technology, for its transmission rate of 1Gbps to lay the foundation.

802.11AC the operating frequency of each channel will be increased from 802.11n 40MHz, to 80MHz or even 160MHz, plus about 10% of the actual frequency modulation efficiency, the final theoretical transfer speed from 802.11n to 600Mbps the highest 1Gbps. Of course, the actual transmission rate may be between 300mbps~400mbps, close to the current 802.11n actual transmission rate of 3 times times (the actual transmission rate of 802.11n wireless router is between 75mbps~150mbps), enough to transmit a multi-channel compressed video stream simultaneously on one of the channels.

In addition, the 802.11AC will be backwards compatible with all of the existing and upcoming standards and specifications for the 802.11 full range, including the upcoming 802.11s wireless network architecture and 802.11u. Security, it will fully comply with all the content of the 802.11i security standard, so that wireless Wi-Fi can achieve the security of enterprise-level user needs.

In accordance with the goal of 802.11a C, the future 802.11AC will enable the enterprise or the family to achieve seamless roaming, and in the roaming process can support the corresponding security, management and diagnostic applications such as Wi-Fi products. Advantages of 802.11ac

Wireless LAN equipment Manufacturers learn a lot from the 802.11n. These experiences were clearly combined to 802.11ac. The two key features of 802.11n, MIMO (multiple-in-and-out), and channel binding form the basis for 802.11AC enhancements, as well as some more complex optional features.

The first good thing about 802.11AC is that it's designed specifically for the 5GHz band. This band provides greater flexibility for channel binding of one of the key data rate enhancements. Channel bindings are typically used in current 802.11n devices. Because most 802.11n devices are designed for the 2.4Ghz band, channel binding in this band can cause serious interoperability problems. The 5GHz band provides more channels in a larger space, and is far less sensitive to interference from consumer electronics such as baby monitors, wireless surveillance cameras, and microwaves.

Additional Protocol enhancements are also specifically designed to make channel bindings impossible to cause interoperability problems. This includes the ability of the device to assess whether adjacent bands are clear and available for channel binding and to allow the device to retain a wider bandwidth before data transfer. This allows the channel bindings to be increased from 40MHz in 802.11n to 802.11ac from 80 to 160MHz. Making channel bindings less intrusive and allowing wireless devices to be used by default is key to achieving a faster data rate in 802.11AC.

The second benefit of 802.11AC is that, despite a significant increase in data rates, power consumption is reduced compared to 802.11n-like capacity. This is a huge victory.

802.11N began to increase the power limit (especially for mobile/portable devices) to a level where most portable devices could not take advantage of the full benefits of 802.11n. By using a more efficient data encoding mechanism, 802.11AC allows the device to use fewer transmission paths while still achieving higher data rates. It is the extra RF transmission chain that really consumes power.

Also, given that a major application of 802.11AC is the release of video within the home, power issues can be further mitigated, as many devices will not be mobile, such as your 52-inch LCD TV. This means that AC power is available. Video transmission is generally one-way. This means that the PC or digital video recorder will deliver the video. These devices require more power. The TV or ipad is primarily a high-bandwidth signal. These devices require less power.

Finally, the 802.11AC introduces an optional feature. A transmitting device can transmit data such as streaming video to multiple receiving devices at the same time. Currently, 802.11 communication is actually a point-to-point communication. If the same video stream needs to be sent to three clients, it needs three times times the bandwidth. With 802.11AC, bandwidth usage will be more efficient. the future of 802.11ac

802.11AC will become faster and quicker, as we mentioned earlier, the theoretical maximum of 802.11ac can reach 7Gbps. Although in real life and application will not really reach the theoretical maximum, but in the next few years if the download speed has been promoted to 2Gbps, you should not be surprised, 256mb/seconds of download speed will become very mainstream.

Now, more and more hardware equipment manufacturers are beginning to find out how to really play 802.11ac potential products. Broadcom (Broadcom), Qualcomm (Qualcomm), MediaTek (MediaTek), Marvell and Intel are all beginning to prepare for the 802.11AC standard. On the other hand, the IEEE draft specification has gone through several rounds of balloting, and the Wi-Fi Alliance, Greg Ennis, says the final IEEE decision is expected in early 2014. So, if you start seeing more and more 802.11ac products in the market from now on, don't doubt, this is the future trend.