Stefan Mileschin

Way back at MWC we saw Qualcomm Atheros demonstrating single spatial stream 802.11ac on a MSM8960 MDP, where it was pushing 230 Mbps to a nearby 802.11ac router. I talked about the WCN which works in conjunction with the WLAN PHY onboard the MSM8960 SoC, but got the part number wrong apparently (I said it was WCN3860). Qualcomm Atheros is now making that particular part official, and it's the WCN3680, a single spatial stream 802.11ac and BT 4.0 combo solution that works in conjunction with either MSM8960 or the quad core APQ8064 Krait SoCs.

Back then, I suspected that WCN3680 might not be implementing 256QAM (which is an optional 802.11ac feature), based on the 230 Mbps transfer rate we saw and talk of this being Airgo IP. The announcement states that WCN3680 is capable of a full 433 Mbps single spatial stream PHY rate, which corresponds to MCS-9, and thus includes 256QAM support. The announcement goes on to note that end user throughput will be around 200 Mbps, which is much closer to what we saw at the MWC demo, which is a little confusing. Either way, mobile 802.11ac is nearly upon us, as Qualcomm Atheros and the other combo chip players continue to trickle out announcements. This solution for MSM8960/APQ8064 again uses the on-SoC baseband for WLAN, WCN3680 is that external RF which enables it. This is roughly analogous to how the cellular baseband situation works - you use the on SoC baseband and external RF.

The other announcement is Qualcomm Atheros' beefier 802.11ac solution which I've been waiting to hear about. This is the QCA986x family, which does 802.11ac and BT 4.0 solution over PCIe, which comes in a 2 or 3 stream variant (QCA9862 and QCA9860, respectively) with full MCS-9 support (either 867 Mbps for 2 stream or 1.3 Gbps for 3 stream). This is a PCIe solution which will no doubt make its way into notebooks and other desktop platforms. Both QCA986x and WCN3680 are currently sampling.

http://www.anandtech.com/show/5942/q...80-and-qca986x