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

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

doc.: IEEE /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 ( GHz) environment verified with spectrum analyzer

doc.: IEEE /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

doc.: IEEE /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 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

doc.: IEEE /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 link by 0.5 m to model scenario where WLAN connectivity is being using simultaneously with Bluetooth voice call Test measurements conducted for n 40 MHz, n 20 MHz, and b Test conducted with a range of throughput –Max throughput for each system –Comparable throughputs for each system to compare impact based on the same offered load –Minimum throughput tested is 1 Mbps to model typical internet access

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

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

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

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