1. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 1 Measurements of Coexistence between 802.11n 40MHz and Bluetooth Date: 2008-07-14 Authors:

2. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 2 Abstract Over-the-air measurements of Bluetooth voice performance in the presence of 802.11n 40 MHz link. Results show no degradation to quality of the Bluetooth voice link.

3. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 3 Test Setup Wired controlled network on Gigabit switch IxChariot 6.2 traffic is managed on controlled network WiFi and Bluetooth networks are separate subnets WiFi link is 2.4GHz/40MHz capable Bluetooth version 2.0 link is piconet with TCP/IP stack Windows XP SP2 with Chariot endpoint 6.25 is used for all stations Clean RF (2.40-2.48GHz) environment verified with spectrum analyzer

4. doc.: IEEE 802.11-08/0893r0 Submission Deployment Layout Test setup is contained entirely in the one room of a residential house Room is a basic den –10 ft x 20 ft –wood paneling WiFi STA located at L0

5. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 5 Test Procedure Controlled network: –All nodes are on the same network –All nodes have static IP addresses –Chariot management traffic is on the controlled network Bluetooth baseline procedure: –All WiFi nodes are powered down –Throughput averaged over 2 minute duration with 3 iterations –2 pairs – one per direction (master to slave, slave to master) –Voice RTP throughput: VoIP pair with G.711a (64kbps) codec Bluetooth with 802.11 traffic procedure: –Bluetooth procedures are the same as baseline –Add WiFi traffic for same duration –802.11n (20MHz and 40MHz) traffic: 4 pairs – two per direction (Tx, Rx), high performance throughput.scr script –802.11b traffic: 2 pairs – one per direction (Tx, Rx), throughput.scr script

6. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 6 Test Methodology Bluetooth devices forming Bluetooth link separated by 1 m to model typical distance between headset and cell phone Bluetooth link separated from the 802.11 link by 0.5 m to model scenario where WLAN connectivity is being using simultaneously with Bluetooth voice call Test measurements conducted for 802.11n 40 MHz, 802.11n 20 MHz, and 802.11b Test conducted with a range of 802.11 throughput –Max throughput for each 802.11 system –Comparable throughputs for each system to compare impact based on the same offered load –Minimum 802.11 throughput tested is 1 Mbps to model typical internet access

7. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 7 Results – Bluetooth Measurement Baseline No 802.11 present Bluetooth traffic typeRTP Bluetooth traffic categoryVoice Throughput128 kbps Mean Opinion Score (MOS) 3.74 (±0.11) PER0.08%

8. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 8 Results – Bluetooth Performance with 802.11 Link Present 802.11 traffic type: TCP BT link same as baseline

9. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 9 Analysis of Results All BT MOS measurements in the presence of 802.11n 40MHz are comparable to that of the BT baseline No measurable impact due to offered load No measurable difference between 802.11n 40 MHz, 802.11n 20 MHz, and 802.11b

10. doc.: IEEE 802.11-08/0893r0 Submission July 2008 Eldad Perahia (Intel)Slide 10 Conclusions Over-the-air measurements conducted to determine coexistence between 802.11n 40 MHz and Bluetooth voice link Measurements demonstrate that neighboring 802.11n 40 MHz link has no impact to quality of nearby Bluetooth voice link