The Connect802 engineering team has a deep understanding of 802.11ac and 802.11ad technology and provides 802.11ac 802.11ad design consulting, 802.11ac and 802.11ad products and complete support.


CSS Mega Menu Css3Menu.com

 

Connect802 is an authorized equipment and software reseller.

Tutorial Topic Sections
Intended to be read in sequence

1 - Establishment of the 802.11ac and 802.11ad Standards 6 - QAM Modulation and OFDM Symbols
2 - Transmit Output Power 7 - Comparing 802.11ac and 802.11ad QAM and OFDM Implementation
3 - Oxygen Absorption of RF at 60 GHz 8 - Real-World Expectations for 802.11ac and 802.11ad
4 - Channel Width and Guard Interval 9 - Antenna Differences: Beamsteeering, Gain and Range
5 - MIMO and Implementation of Multiple Spatial Streams 10 - Overall Perspective and Conclusions

Overall Perspective and Conclusions

802.11ac follows the evolution of 802.11b to 802.11g to 802.11n; 802.11ad is NOT on that same path. 802.11ad stands alone as a potential HDMI cable replacement or for other short-range, low-user-density applications. Remember that there are only 4 802.11ad channels versus a potential for 24 802.11ac channels in the 5 GHz band. Per-user capacity (for simultaneous users) in an open space under 1 million square feet = (Channel_Count X Per_Channel_Capacity) / Number_Of_Users. The calculation for per-user-capacity based on channel count assumes that the WLAN supports access point load balancing. Because 802.11ac supports 5 times more channels than 802.11ad the number of users that can be supported is also at least 5 times greater. Remember, too, that a single 802.11ac channel reaches out to a range of over 100 to 200 feet indoors – 802.11ad has a range of less than 30 feet.

Let’s put this all in perspective: 802.11ac is a direct evolution of 802.11n; 802.11ad is a short-range, very high-throughput, low user-density solution. 802.11ac provides greater user density and higher per-user throughput than 802.11n but tops out at roughly 500 Mbps per user. 802.11ad is limited to 10 to 30 feet but may provide 2 to 3 Gbps to a single user.

As we stated when we started this discussion: Where 802.11ac is effectively “faster WiFi”, 802.11ad is effectively “wireless HDMI”. 802.11ac will bring greater capacity to a large coverage cell while 802.11ad will provide dramatic throughput to a few users in a small area. 802.11ac is a wireless LAN while 802.11ad is a wireless PAN. The final thought about both 11ac and 11ad is: don’t forget that the throughput bottleneck may be your wiring or your Internet connection. You can’t push multi-gigabit 11ac or 11ad through Cat5e 100 Mbps Ethernet or even Cat6e Gigabit Ethernet. All the fantasies about greater-than-Gigabit wireless cell capacity will have to wait until the wired infrastructure is upgraded. A single 802.11ad access point in a home may provide greater-than-Gigabit connectivity for HDMI HD video (between computer and television). A single 802.11ac access point in a conference room may provide greater-than-Gigabit peer-to-peer connectivity. 11ad or 11ac connectivity back to the Internet or to servers in a data center will have to wait for greater-than-Gigabit wired infrastructure.