doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 1 Blue Tooth\WiFi coexistence Notice: This document has been prepared to assist IEEE It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE Working Group. If you have questions, contact the IEEE Patent Committee Administrator at. Date: May, 2006 Authors:

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 2 Abstract This document introduces the description of WiFi\BlueTooth coexistence Measurement methodology and metric for performance testing of wireless LAN devices. This presentations is in associate with a draft text [2].

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 3 Agenda Purpose Measurement Setup Traffic use cases Measurement procedure Example of measurement results Summary

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 4 Purpose This test is an example of WiFi coexistence test with other non WiFi devices and the effect of the coexistence on the WiFi performance. There are two basic measurements tested: –WiFi traffic degradation caused by BT interference. –BT traffic degradation caused by WiFi traffic. This test is applicable to an infrastructure BSS client configurations as well as to IBSS.

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 5 Test Setup -conductive Two setups may apply for this measurement as described below: –Conducted setup: The first setup is a variant of a setup defined in TGT draft [1] for throughput measurement, the “Throughput versus attenuation in a conducted environment” described in [1] section 6.2. In this case the attenuation is set at the level that provides maximal TPT on the WiFi NIC device. The modification to the setup is adding a wired connection between the BT device on the DUT (BT1) to another external BT device (BT2). There are 4 emulated links: –RF path between the 2 BT devices, –RF path between the WiFi NIC and AP, –interference path between the on board WiFi and on board BT –interference between the external BT device and the WLCP. Those emulated links are done by controlled attenuators. The isolation (attenuations) in these links are the test variables. The separation between the WiFi NIC and the onboard BT device RF paths emulates the specified separation in the DUT (usually 40 dB for laptops).

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 6 Test Setup-OTA –OTA setup: The second setup is similar to the “Throughput versus range in an OTA environment” described in [1] section 6.6. In this case the range and orientation between the WiFi NIC and the AP is the controlled variable. The variation to this setup is adding a BT device to the DUT and external BT device on another STA. The distance between the two BT devices is a test parameter and one of the outputs is the BT capability to maintain good link. –In both cases the entire system is suitably isolated from extraneous interference and other unwanted signals. –The WiFi NIC performance is tested using a Traffic Generator and Analyzer. –The BT performance testing is divided into two cases: creating an audio streaming connection and playing a file. Recording a file on the receiving station and comparing it to the source file with a voice analysis software using a PESQ algorithm. Create an FTP connection and download a file with a fixed size (100Mb). Measuring transfer time will indicate the link degradation.

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 7 BT\WiFi coexistence Measurement setup

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 8 Traffic use cases WiFi device data traffic degradation while BT device running audio streaming traffic in the background and Vice Versa. WiFi device data traffic degradation while BT device running data traffic in the background using FTP service and Vice Versa. WiFi device voice traffic degradation while BT device runs audio streaming traffic in background and Vice Versa.  The reason for choosing the 3 use cases above is derived from the “worst case” scenario for BT\WiFi devices: in one case the user sends\receives data from the WiFi WLCP while using a BT head set to pass audio traffic. A more complicated use case is creating VOIP call using the WiFi WLCP while using a BT head set.

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 9 Traffic use cases -Definition WiFi device data traffic degradation with BT device audio streaming traffic in background and Vice Versa. In this case the the WiFi device sends\receive TCP data packets generated by the traffic generator while the BT device transmit\receive audio streaming data (voice) from the external STA. All the combinations of transmit\receive should be tested. WiFi device data traffic degradation with BT device data traffic in background using FTP service and Vice Versa. In this case the the WiFi device sends\receive TCP data packets generated by the traffic generator while the BT device transmit\receive data using FTP service (copy a file to and from the DUT) from the external STA. All the combinations of transmit\receive should be tested WiFi device voice traffic degradation with BT device audio streaming traffic in background and Vice Versa. In this case the case the WiFi device sends\receive voice data packets generated by the traffic generator while the BT device transmit\receive audio streaming voice from the external STA. the WiFi AP and client should support QOS. All the combinations of transmit\receive should be tested

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 10 Measurement Procedure The measurement procedure depends on the operation state; in general it looks as follows: 1.Set up both DUT and BT device according to base configuration 2.Create the desired traffic type between the two BT devices. 3.Generate the required traffic between the WLCP and the DUT. 4.Change attenuation between DUT and WLCP so the path loss will cover the range describe in [2]; Measure and report TPT for every attenuation step. 5.Set the path loss between the DUT and WLCP to 60dB (this is generally lowest attenuation that gives “best TPT”) and run traffic on that attenuation. 6.Create the requested traffic type between the two BT devices 7.Measure the degradation of the BT data.for audio data use voice analysis SW, for FTP use time measurement.

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 11 Example of WIFI DUT traffic degradation due to BT interference

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 12 Example of BT data degradation (Voice) due to WIFI traffic measured with voice analysis SW (score is given in MOS – Mean Opinion Score according to PESQ algorithm) TX 11B11G testBaselinetestbaseline MOS score RX 11B11G TestBaselinetestbaseline MOS score

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 13 Summary The BlueTooth\WiFi coexistence measurement has been proposed The proposal contains: –Purpose of the measurement –Descriptions of equipment and test setup –Description of operation states –Baseline, modifiers and test parameters –Calibration and precision requirements –Measurement Procedures –Reporting results requirements –Example Recommendation: –Recommend TGT to adopt the content of document xxxx t-WiFi-bluetooth-coexistence.doc. into the P draft. References: [1] IEEE TGT draft D0.7 [2] xxxx t-WiFi-bluetooth-coexistence.doc.

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 14 Straw polls Does the TGT in favor of having Coexistence tests between devices and other devices in TGT draft? Y/N Does the TGT in favor of having a text describing the presented measurement and metric in TGT draft? Y/N

doc.: IEEE /0741r0 Submission May 2006 Avi Gabay, IntelSlide 15 Feedback?