MIMO performance Test Methodology proposal doc.: IEEE 802.11-06/0742r0 May 2006 MIMO performance Test Methodology proposal Date: May, 2006 Authors: Notice: This document has been prepared to assist IEEE 802.11. 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 802.11. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures <http:// ieee802.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 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 <stuart.kerry@philips.com> 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 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at <patcom@ieee.org>. Lemberger Uriel, Intel Lemberger Uriel, Intel

doc.: IEEE 802.11-06/0742r0 May 2006 Abstract This document introduces a simplified and basic concept for testing Throughput of MIMO system. It describes measurement methodology and metric for TPT performance testing of 802.11n wireless LAN devices. Lemberger Uriel, Intel Lemberger Uriel, Intel

Agenda Purpose Setup Traffic use cases Measurement procedure Summary doc.: IEEE 802.11-06/0742r0 May 2006 Agenda Purpose Setup Traffic use cases Measurement procedure Summary Lemberger Uriel, Intel Lemberger Uriel, Intel

doc.: IEEE 802.11-06/0742r0 May 2006 Purpose This test is a simple baseline example of WiFi TPT test for .11n WiFi devices. There are two levels of complexity of the test setup: Using net of attenuators and fixed phase shifters. Using complex channel simulator. This test is applicable to an infrastructure BSS as well as to IBSS. Lemberger Uriel, Intel Lemberger Uriel, Intel

Test Setup - Conductive May 2006 Test Setup - Conductive This test can be carried in 3 types of environments: Conducted setup: In analogy to the conductive setup described in [1] section 5.3 we use similar setup with a bank of mxn attenuators instead of one in the above. Schematic diagram for 3x3 system described in fig 1. Lemberger Uriel, Intel

May 2006 Conductive environment Measurement setup Generic Test Setup (up to 3x3 solution) for MiMO conducted Performance Tests Lemberger Uriel, Intel

May 2006 Test Setup - Chamber Two setups may apply for this measurement as described below: Chambered setup: In analogy to the chamber setup described in [1] section 5.2 we use similar setup with a bank of m attenuators in serial with the antennas of the WLCP instead of one in the above. Schematic diagram for 3x3 system described in fig 2. Lemberger Uriel, Intel

May 2006 Chamber environment Measurement setup Controlled OTA test inside a screen room – Test setup proposal Lemberger Uriel, Intel

Test Setup - OTA OTA setup: May 2006 Test Setup - OTA OTA setup: OTA setup is similar to the setup described in [1] sections 5.4-5.6. Test equipment should be capable to handle the higher data rates involved in 11n devices testing. Lemberger Uriel, Intel

Calibration and precision requirements doc.: IEEE 802.11-06/0742r0 May 2006 Calibration and precision requirements Calibration of the attenuators and the phase shift contributed by the connecting lines between the antennae is critical for the accuracy of the measurement. Each link between 2 antennae should be measured and calibrated per channel. Lemberger Uriel, Intel Lemberger Uriel, Intel

The test cases will include: May 2006 Proposed Test cases The test cases will include: Ideal multi-stream network Orthogonal streams Non ideal reception with correlation between streams Lemberger Uriel, Intel

Measurement Procedure May 2006 Measurement Procedure The measurement procedure is similar to the existing SISO testing with additional paths to control. The test procedures emulate major use cases. Simulating N ideal links – Hii are running simultaneously from (min to max) attenuation in 1dB steps (can be a larger step as well) Hij are set to maximum attenuation. Simulating N orthogonal links– Hij=Hii-6dB 0deg,(j=i+1) Hik=Hii-6dB 180deg (k=i+2) Lemberger Uriel, Intel

Measurement Procedure Test Description – Proposed Test cases May 2006 Measurement Procedure Test Description – Proposed Test cases Simulating each Tx antenna received by each Rx antenna (3 ideal signals and other signals are attenuated) – Hii are running simultaneously from (min to max) attenuation in 1dB steps (can be a larger step as well) Hij=Hii+ fixed offset of [6,12,18] dB Simulating a use case where there is a Rx signal power delta between all of the signals received – For example in 3x3 use case – H33=H22+6dB=H11+10dB ; Hij=Hii + (-1)^(i)*( 6dB), running from (min to max) attenuation in 1dB step. Simulating Pure MRC (Maximum Ratio Combining) mode – H11 is running from (min to max) attenuation in 1dB step. H12=H11+ fixed offset in each attenuation of [0,6,12] dB Changing "lanes" - exact steps for each "lane" will be decided by trial and error Simulates OTA real environment where rapid changes occur (Similar concept to the conductive Diversity test in legacy mode), Lemberger Uriel, Intel

“Changing lanes” Test example May 2006 “Changing lanes” Test example A11=A21+4 =A31+ 8 A22=A12+4 =A32+ 8 A33=A13+4 =A23+ 8 50dB 20dB -5dB +5dB Lemberger Uriel, Intel

Summary The 11n MIMO TPT test has been proposed The proposal contains: doc.: IEEE 802.11-06/0742r0 May 2006 Summary The 11n MIMO TPT test has been proposed The proposal contains: Purpose of the measurement Descriptions of test setup modifications Baseline channels, modifiers channels Calibration and precision requirements Description of test cases Measurement Procedures Recommendation: Adopt this concept as a baseline for MIMO testing proposal References: [1] IEEE802.11 TGT draft D0.7 Lemberger Uriel, Intel Lemberger Uriel, Intel

May 2006 Straw polls Does the TGT in favor of having 11n devices testing in TGT draft? Y/N Does the TGT in favor of having this concept of measurement and metric for MIMO tests in TGT draft? Lemberger Uriel, Intel