July 2008 doc IEEE 19 08 0027 00

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth IEEE 802. 11 n 40 MHz Impact on BT Performance Authors: Date: 2008 -07 -16 Notice: This document has been prepared to assist IEEE 802. 19. 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 802. 19. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures <http: // ieee 802. org/guides/bylaws/sb-bylaws. pdf>, 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 TAG 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 <shellhammer@ieee. org> 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 802. 19 TAG. If you have questions, contact the IEEE Patent Committee Administrator at <patcom@ieee. org>. Submission 1 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth Outline • Motivation • Simulation Scenario and Assumptions • WLAN Interference Calculations • Results • Conclusions Submission 2 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth Motivation • IEEE 802. 11 n standard proposed an optional 40 MHz transmission • Impact of 40 MHz transmissions on non-IEEE 802. 11 devices has not been investigated • This work addresses impact of 40 MHz transmissions (in 2. 4 GHz) on BT devices Submission 3 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth Scenario Under Investigation • Networks: – WLAN Network consists of one STA and one AP • – 64 Kbps voice traffic from BT_Master to BT_Slave carried using SCO or e. SCO packets 60 Mbps FTP traffic from STA to AP for 40 MHz option and 30 Mbps FTP traffic from STA to AP for 20 MHz option PHY – – – • BT Network consists of BT Master and BT Slave Traffic – • The STA is closer to BT transmitting device Tx Power: 15 d. Bm WLAN 20 MHz PHY rate: 104 Mbps WLAN 40 MHz PHY rate: 162 Mbps Aggregation: 6 KB maximum BT PHY: 4 d. Bm Tx Power and PHY rate of 1 Mbps for SCO and 2 Mbps for e. SCO Location – – – Submission AP: 40 meters away from STA: 1 meter away from BT Master and BT Slave distance: 1 meter 4 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth WLAN Interference on BT • WLAN interference power in BT receiver • Substituting interference for noise, SNR for the interfered bits a • Received BT power and WLAN interference at BT receiver is c Submission 5 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth PER Calculations • Given that BT and WLAN overlap in frequency, and an overlapping interv • For a given run, the BER for the interfered bits is obtained based on the SN • The overall PER is obtained from averaging the PER’s found in different ru Submission 6 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth BER Curves • BER for GFSK and pi/4 -DQPSK in presence of AWGN (Ref[1] &[2]) Submission 7 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth BT PER Increase Using 20 MHz as Baseline Submission 8 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth BT Throughput Reduction Using 20 MHz as Baseline Submission 9 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth BT PER Increase with Aggregation Using 20 MHz as Baseline Submission 10 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth BT Throughput Reduction with Aggregation Using 20 MHz as Baseline Submission 11 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth Conclusions • 40 MHz operation drastically degrades HV 3 performance • If voice performance is already at a threshold, 10% increase in PER is disastrous • 40 MHz operation in 2. 4 GHz is harmful to non-WLAN networks • IEEE 802. 11 n should consider removing 40 MHz in 2. 4 GHz Submission 12 Texas Instruments

July 2008 doc. : IEEE 19 -08 -0027 -00 -0000 -40 MHz-11 n-imapct-on-bluetooth References • [1] D. Patrick and R. Morrow, “Wireless Network Coexistence”, Mc. Graw-Hill Professional 2004. • [2] Agilent Technologies, “Bluetooth Design Guide”, August 2005. • [3] 19 -08 -0018 -01 -0000 -40 mhz-11 n-bluetooth-simparameters. doc Submission 13 Texas Instruments