Making Wi-Fi Suck Less with Dynamic Beamforming G.T. Hill Director, Technical Marketing www.ruckuswireless.com
What We ll Cover 802.11n overview and primer Beamforming basics Implementation
Lot of Questions Surrounding 802.11n Where do I point these things? Will I get the promised performance? Why is it so expensive? Will I get better range and reliability?
WANTED: Consistent Performance at Range 200 Mbps With 802.11n There is Much More to Lose D T H Desired performance B A N D W I What you really get T I M E
802.11n Multi-Radio Techniques Maximal Ratio Combining Spatial Multiplexing Cyclic Delay Diversity Data A Data B Multiple receive transmit radios Backwards compatible with 802.11a/b/g a/b/g devices devices (legacy receiver) Combines Vary the phase multiple of extra signals transmit of varying signals phase to minimize due to self-interference multipath Multiple transmit/receive radios Requires support on both ends Sends data in parallel making use of multipath and DSP to decode Sensitive to propagation environment Number of radios must equal number of spatial streams Multiple transmit radios Backwards compatible with legacy devices Vary the phase of extra transmit signals to minimize self-interference
Spatial Multiplexing Decomplexed 123 Data Stream 123456 Transmit Streams 456 Transmitter and receiver both participate Concurrent transmission on the same channel N-fold increase in throughput Requires MIMO APs and STAs B i bl t l t l t l th i t it f th i l th Being able to completely control the integrity of the signal path is essential to get the performance and reliability you re expecting
Not All Beamforming Created Equal Uses Antennas, Chip logic or Both to Direct Signals to a Receiver Goals Improved SNR Higher data rates More reliable connectivity Decrease extraneous signal Transmission energy is directed in the direction of the client, and not in all directions around the AP. Transmit Beam forming (chip-based) Xirrus Uses Cisco directional antennas This significantly decreases co- channel Cisco interference around the AP, increases Standards-based RSSI SNR and at the client proprietary versions Ruckus Uses dynamic antenna array with switching logic Static Adaptive Array (antenna-based)
How Dynamic Beamforming Works Smart antenna directs Wi-Fi signals over the best paths to each client As clients move dynamic beamforming automatically switches signal path Sources of interference are rejected, nullified Uses antenna diversity and explicit signal path control, multipath to steer signals around impenetrable obstacles Smart antennas make better neighbors Central controller automatically controls AP transmit power and channel assg assignment ZoneFlex AP Metal Wall
Dynamic Beamforming Benefits Interference Highly reliable, resilient client connections Constantly forms and steers Wi-Fi signals over the best performing signal path on a per packet basis Uses multipath to its advantage Leverages antenna diversity it to increase reliability Uses client MAC ACKs to ensure delivery at the best data rate with lowest packet loss Automatically adapts to real-time changes in environment without human intervention Extends signal range (Wi-Fi coverage) 2 to 4 times with fewer APs Radically simplifies RF planning, WLAN deploymentand administration Delivers predictable performance at range
Consistent Performance at Range Typical 802.11n AP AP with Dynamic Beamforming 200 ft 200 ft 125 ft Upper Floor 125 ft AP 200 ft 200 ft 125 ft Lower Floor 125 ft 125-150 Mbps 100-125 Mbps 75-100 Mbps 35-75 Mbps AP on upper floor
Smart Antenna-Based Beamforming Allows concurrent support for spatial multiplexing, MRC and beamforming Extends signal range by up to 10dB Uses feedback from client to ensure highest data rates, lowest packet errors Vertically polarized antenna elements Auto RF signal optimizer (based on device orientation) Horizontallypolarized antenna elements
Automatic Interference Mitigation Minimizes Packet Loss and Re Transmissions, Increases Reliability Interference mitigated by positioning antenna nulls in specific directions Avoiding interference delivers more benefits than a stronger signal Better throughput More predictable connectivity
Flexible Deployment Options ZoneFlex 7962 ZoneFlex 7762 24 2.4 GHz Guest 2.4 GHz Voice 5GHz Mesh n 2.4 GHz Guest MESH n ZoneDirector 2.4 GHz Employee 2.4 GHz Voice 5 GHz Employee2 ROOT 2.4 GHz Voice FlexMaster Remote Management INTERNET BEAMFORMING Minimizes the number of APs to cover given area Allows more flexible deployment of APs Is ideal for wireless meshing (deploying APs without t Ethernet) t) Perfect for multimedia
Dynamic Beamforming Top 10 (Summary) 1. Delivers more consistent performance at range 2. Leverages client feedback to ensure highest data rates 3. Reduces number of APs required 4. Increases wireless reliability through switchable antenna diversity 5. Ideal for more reliable wireless meshing where Ethernet isn t possible 6. Eliminates need for future site surveys 7. Perfect for latency-sensitive applications (voice, video, etc.) 8. Mitigates packet loss by automatically selecting better signal paths 9. Adapts to wireless interference and environmental changes 10. Requires no manual tuning or human intervention, no client anything
G.T. Hill Director, Technical Marketing www.ruckuswireless.com