The second generation of 802.11ac enables a few optional (WiFi Alliance certified) features:

• 4-stream configurations (up from 3-stream previously)
• Up to 160MHz channels (up from 80MHz), and
• Multi-user MIMO (MU-MIMO)
  

Enhanced with a new algorithm-based technology, Qualcomm's solutions are promising to offer two to three times more network capacity and are designed to optimize the way Wi-Fi devices are served to make the most of that additional capacity.

MU-MIMO is a new way for Wi-Fi networks to operate. With standard Wi-Fi, clients are served sequentially; during this time, only one device is sending and receiving information, thus only a small portion of network capacity is being used. The accumulation of these sequential events creates a drop in throughput and capacity as more devices join the network. This situation can be further exacerbated when combined with on-demand high resolution video content. MU-MIMO enables simultaneous transmission to groups of clients, making more efficient use of available Wi-Fi network capacity and speeding up transmissions.

Qualcomm Atheros created algorithms that manage the complexities of simultaneous connections in a VIVE 11ac network. The algorithm-based technology is designed to dynamically adapt to changes in channel conditions, device movement and application requirements to maximize throughput and device performance.

In order to extract the maximum benefits of MU-MIMO, it must be used on both sides of the connection. To accelerate the benefits of MU-MIMO for more Wi-Fi users, Qualcomm Atheros is providing an ecosystem of solutions for networking products, as well as smartphones, tablets, computers, consumer electronics and automobiles.

Qualcomm Atheros introduced the QCA9980 and QCA9982 solutions for routers and gateways, and the QCA9990 and QCA9992 solutions for enterprise access points. These 3- and 4-stream, single-chip solutions feature MU-MIMO, 256-QAM modulation, and explicit and implicit beamforming to meet carrier and enterprise requirements. The QCA998x and QCA999x are expected to sample in the second quarter of 2014.

The latest smartphones are using 1-stream 11ac, while many mobile, CE and vehicles are moving to 2-stream 11ac to accommodate more bandwidth-intensive media applications. The necessary receiver hardware is built into Qualcomm VIVE 11ac solutions for smartphones, tablets, connected TVs and other media devices.

MU-MIMO is also built into all of Qualcomm Atheros' latest 11ac client solutions, and is supported on the Qualcomm Snapdragon 805 and 801 mobile processors.

• The QCA6174, designed for tablets and high-end smartphones, combines 2-stream 11ac with Bluetooth 4.1 to provide more than 600 Mbps throughput over Wi-Fi.
• Qualcomm Atheros' WCN3680 integrates 1-stream 11ac, Bluetooth 4.1 and FM into the Snapdragon mobile processors, providing low-power connectivity for smartphones and tablets.
  
• The QCA9378 is Qualcomm Atheros' new 2-stream VIVE solution for connected TVs, set-top boxes and other entertainment devices.
• The QCA6574 is the first automotive solution to combine 2-stream 11ac and Bluetooth 4.1 for in-car communication, media infotainment and point-to-point connections.

The company expects the first home networking equipment with one of its chipsets to arrive at the end of the year or during the first quarter of next year. Enterprise equipment will arrive in the middle of 2015, at the earliest.

But until the Wi-Fi Alliance starts conducting interoperability tests there is no guarantee that routers and clients from different vendors will be compatible. That process is expected to start late this year or in the beginning of 2015.