无线加速数据传输和通信

　　无线加速数据传输和通信

　　现在几乎所有的系统都是无线的，而不仅仅是连接到互联网。为连接笔记本电脑、平板电脑、平板电视、Blu Ray播放器、音频系统、家庭医疗系统，甚至是白色家电（冰箱、恒温器、空调和供暖系统等），几乎可以成为连接系统的免费连接。连接所有的设备，大量的无线接口，包括蜂窝无线电（GSM、LTE等），蓝牙，Wi-Fi的多种形式（802.11xx，Miracast，WiDi，WiGig）、ZigBee、Z-Wave无线接口，而其他如WISA（无线扬声器和音频协会）。

　　以前的文章研究的进展发生与蓝牙接口（见，例如，在高新区的文章“蓝牙是超低功耗”和“蓝牙低功耗技术不只是一个蓝牙版本–这是一个全新的技术”），所以这篇文章将集中在Wi-Fi和其他非蓝牙无线的进展。

　　In the Wi-Fi arena， the fifth-generation Wi-Fi is called 802.11ac.The ac standard defines the Wi-Fi interface operating at 5.4 GHz， with backward compatibility with the popular 802.11n standard， which is in wide use today. There are several options when implementing the 802.11ac interface depending on the data transfer speed desired – the maximum data rate when a 3 x 3 or 4 x 4 MIMO transmit/receive interface is implemented can hit about 1.3 Gbits/s， and that speed drops to 866.7 Mbits/s for a 2 x 2 channel system. Additionally， a 1 x 1 transmit/receive system can deliver a data transmission speed of 433.3 Mbits/s， which is almost triple the speed of today’s 802.11n Wi-Fi interfaces. Keep in mind， however， that as with all other flavors of 802.11 the actual throughput users will get with 802.11ac will be much less than the raw throughput. Table 1 offers a brief comparison of 802.11n and 802.11ac characteristics.