January 2004 doc IEEE 802 11 040092 r

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 CTIA Industry Standard - Over-The-Air Testing of Wireless Devices Prepared by Dr. Michael Foegelle ETS-Lindgren (512) 531 -6400 foegelle@ets-lindgren. com Presented by: Stephen Berger TEM Consulting (512) 864 -3365 stephen. berger@ieee. org Submission 1 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 CTIA Status u Cellular Telecommunication and Internet Association (CTIA) Certification Program established in 1991. u u Created to provide the wireless industry with an unbiased, independent and centralized product evaluation service. 3 -Part Evaluation Program u u u 1. Testing to wireless industry technology platform standards. 2. Over-the-air performance tests. 3. FCC Type Acceptance Tests Certified products also required to contain information on driver safety, consumer safety, audio accessibility, and hands-free capability. CTIA Certification Program Working Group (CPWG) develops test requirements for parts 1 and 2. u u 1. CDMA, GSM, TDMA, and Analog test plans. 2. Over-the-Air Performance Test Plan (Antenna Test Plan). Submission 2 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 CTIA Status u u u Manufacturers wishing to sell CTIA Certified mobile devices must perform all required tests. Some US wireless carriers have made CTIA Certification a requirement. Tests for Parts 1 and 2 must be performed at a CTIA Authorized Test Lab (CATL). CATLs are A 2 LA Accredited. Part 3 tests must be done by FCC authorized lab. Mobile Station Over the Air Performance Test Plan (formerly termed Antenna Test Plan) for Part 2 provides test methods for measuring radiated power and sensitivity performance of mobiles, in both free-space and against simulated human head (SAM Phantom). Submission 3 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 CTIA Status u u ETS-Lindgren became first CTIA Authorized Test Lab (CATL) for over-the-air performance testing (Part 2) in December 2002. Followed by Intertek Testing Services of Lexington, Kentucky, using an ETS-Lindgren AMS-8000 Antenna Measurement System. Other test labs in USA are working to add the capability since all phones must have Part 2 tests performed by a CATL to be CTIA Certified. A number of manufacturers are also equipping their Compliance Labs for CTIA Certification and Type Approval Submission 4 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Measurement Overview u u Tests designed to determine wireless device transmitting and receiving properties Transmitted: How much power and where is it going? u u Total Radiated Power (TRP) Radiated Antenna Pattern and power localization quantities such as Directivity and Near Horizon Partial Radiated Power (NHPRP) Antenna Efficiency (TRP vs. PA output power). Receive sensitivity: What’s the lowest signal that can be detected from each direction? u u u Submission Mobile station broadcasts full power as would be the case at lowest RX signal levels (Self Jamming test). Total Isotropic Sensitivity determined similar to TRP. Different frequencies from transmit signals. 5 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Measurement Overview u CTIA Tests are intended to gauge: u Connectivity to the existing service networks Near-Horizon Partial Solid Angle values. u Intended to reduce/replace drive testing. u u Operator influence on the transceiver properties and radiated performance Differences between free-space and SAM phantom. u Phantom tests are NOT radiation absorption, hazard or health and safety tests. Only intended to determine blocking effect of human head on pattern. u Submission 6 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Measurement Overview u Over the Air Test Requirements to obtain CTIA Certification Seal: u Currently, only TRP testing required ~3/4 of the way through one-year evaluation period. u Initial pass/fail criteria to be specified by December. u Proposed two-tiered implementation with tighter requirements imposed by end of 2004 to give wireless manufacturers time to prepare for requirement. u u TIS (Sensitivity) Testing Nearing Implementation Capable of CDMA test as described in test plan. u GSM test requirement to change similar to CDMA. u TDMA test requirement may be eliminated u Test time required for full test (~100 hours for single band retractable antenna phone) may make full spherical TIS impractical to implement. u Submission 7 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Why Measure Radiated Performance? u u u u Radiated “over-the-air” testing is the only way to qualify the entire signal path of the wireless device. Meet regulatory requirements (FCC, etc. ) for Product Type Approval and Health & Safety. Comply to uniform performance standards defined by industry consortia (CTIA, ETSI, …). Provide data to wireless carriers to demonstrate meeting required performance criteria. Detect and reject manufacturing defects. Test mobiles for properation in repair centers. Provide the consumer with a good product. Submission 8 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Typical Test Setup u u u Shielded room isolates the Device Under Test from commercial wireless services and other interference. RF Anechoic Absorbers simulate free-space test environment in chamber. Broadband test antenna(s) provide an over-the-air test link to the DUT. Reference antennas are used to qualify and calibrate a test system. Positioning equipment manipulates the DUT and/or measurement antenna for various tests. Submission 9 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Typical Test Setup u u u Advanced pattern measurement software acquires data and provides full post processing capabilities. A SAM Phantom is used for simulating operator influence. A base station simulator/communication tester is used to establish communication and perform protocol specific tests. A spectrum analyzer is used for radiated power measurements. A vector network analyzer is used for antenna design work, site validation, and range calibration. Submission 10 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u u Measure magnitude & direction of radiating energy to determine performance of a wireless device. Use spherical coordinate system to represent location of each data point. Submission 11 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u u u Typical polar pattern configuration using Azimuth Rotator Measurement Antenna (MA) is fixed, and Antenna Under Test (AUT) is rotated 360°. Spherical techniques add to this configuration. Submission 12 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u u u One method for spherical coverage involves elevating measurement antenna in an arc around AUT. Rotator Axis = f, MA Axis = q Referred to as a distributed axis system since two separate positioners are required. Examples include “arch” systems with MA on track or boom arm, and multi-sensor systems with MA array. Tradeoff between large chamber (2 x range length) or short range length. Difficult to measure q = 180°. Submission 13 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u u Second method involves rotating AUT in two orthogonal axes. Results in change in AUT coordinate system. Rotator Axis (Turntable) = q, Second (Roll) Axis = f Referred to as a combined axis system since both axes are combined into one positioner. Manual positioning of AUT for second axis results in “great circle cut” measurement process, where each rotation results in a complete polar pattern from poleto-pole of spherical coordinate Submission system. 14 u Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u u Automating both axes requires a multi-axis positioning system (MAPS) MAPS can typically acquire data in either great circle or conical cut order. Submission 15 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u In general, same data points can be covered by either conical cut or great circle data acquisition order. Submission 16 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 MAPS Operation (Conical Cut Method) Submission 17 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u Defining rotational axes and polarization directions in terms of a spherical coordinate system in the AUT reference frame avoids confusion between different test systems. Submission 18 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u Typical spherical patterns for a dipole (left) and a standard gain horn (right). Submission 19 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Spherical Pattern Measurement Intro u Range calibration is required to do much more than capture pretty pictures. Without it, only relative values like Directivity may be ascertained. u Precision reference antennas are required in order to obtain suitable results. Submission 20 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Typical Cell Phone Antenna Pattern (Right Ear Phantom Head 836. 5 MHz) Submission 21 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Typical AMS-8000 System Schematic Network Analyzer Multi-Axis Positioning System (MAPS) Spectrum Analyzer 3164 -03 or 3164 -04 Diagonal Dual Polarized Horn Universal Radio Communication Tester Antenna Under Test (AUT) Relay Switch Unit Walkway Windows 2000 based PC running EMQuest software RF Cables GPIB-Bus Fiber Optics for MAPS system MAPS Controller Submission 22 Penetration Panel Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 CTIA Ripple Test Requirements u Thorough System Test u u u Phi Axis Test u u u Two orthogonal orientations (theta & phi) with omnidirectional illumination in two orthogonal polarizations each. Tests chamber and positioning system. Chamber must be in normal testing configuration. Three positions along Phi axis (center and one each ± 150 mm axial offset) with one 150 mm radial offset at each position for a total of six positions. Rotate Phi axis 360° for each position with Theta = 90°. Theta Axis Test u u u Two offsets along each orthogonal axis for a total of seven positions. Rotate 165 degrees for each position. Optional positions allowed to account for mechanical interference issues. Submission 23 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 CTIA Test Site Requirements u < 2. 0 d. B Total Measurement Uncertainty u u u Uncertainty contribution is NOT max. ripple. u u Surface Standard Deviation used to calculate TRP uncertainty. Two required test frequencies 836. 5 and 1880 MHz. u u u Site/MAPS biggest contribution ~1. 25 d. B Extensive uncertainty budget requirements in test plan. High quality spectrum analyzer required to meet budget. EMC Chambers not suitable for meeting this criteria. Required frequencies may be extend in the future. ETS-Lindgren typically performs additional testing to verify chamber installation performance at low/mid/high band. Dipoles and Loops must be symmetrical to ± 0. 1 d. B. u u Tested onsite or certified by A 2 LA accredited calibration lab. ETS-Lindgren 3126 & 3127 calibrations meet this requirement. Submission 24 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Ripple Test Configuration Network Analyzer Spectrum Analyzer 3164 -03 or 3164 -04 Diagonal Dual Polarized Horn Universal Radio Communication Tester 3126 Precision Sleeve Dipoles & 3127 Resonant Loops Relay Switch Unit Walkway Windows 2000 based PC running EMQuest software RF Cables GPIB-Bus Fiber Optics for MAPS system MAPS Controller Submission 25 Penetration Panel Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Range Calibration Requirements u Range Calibration (CTIA “Substitution Part”) required for accurate power measurements. u u Calibrations of standard EMC antennas are insufficient for this application. u u u Single two-step measurement reduces uncertainty over individually applying path loss, RX antenna gain, & cable loss. Calibrated reference antenna used to measure site attenuation. Transmit cable loss calibrated out and gain of reference antenna is applied to relate RX power to isotropic radiated pwr. Require an extremely precise calibration (< few tenths of d. B) to meet uncertainty budget. Other CTIA uncertainty constraints for non-dipole antennas. ETS-Lindgren’s Model 3126 Precision Reference Dipoles are the best solution! u A 2 LA accredited calibration with ~ ± 0. 2 d. B uncertainty typical. Submission 26 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Range Calibration Configuration Network Analyzer Spectrum Analyzer 3126 Precision Sleeve Dipoles 3164 -03 or 3164 -04 Diagonal Dual Polarized Horn Universal Radio Communication Tester Relay Switch Unit Walkway Windows 2000 based PC running EMQuest software RF Cables GPIB-Bus Fiber Optics for MAPS system MAPS Controller Submission 27 Penetration Panel Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 ERP Test ( Mobile transmit power) u ERP test – 3 -D Transmit Antenna Pattern gives: u Effective Isotropic Radiated Power (EIRP) u Total Radiated Power (TRP) u Near-Horizon Partial Radiated Power (NHPRP). u Directivity, Gain, Efficiency, etc. Submission 28 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 ERP Test ( Mobile transmit power ) Communication Antenna on ceiling Spectrum Analyzer Universal Radio Communication Tester Mobile Phone Relay Switch Unit Receive Antenna Communication Antenna on MAPS GPIB-Bus Fiber Optics for MAPS system MAPS Controller Submission 29 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Receiver Sensitivity (Mobile Receiver Loopback Test) u Receiver sensitivity test u Determine minimum received power required to achieve the specified bit error rate at each pos. u Phone transmits full pwr. u Effective Isotropic Sensitivity (EIS) u Total Isotropic Sensitivity (TIS) u Near-Horizon Partial Isotropic Sensitivity (NHPIS) Submission 30 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Receiver Sensitivity (Mobile Receiver Loopback Test) Comm. Rx Ant on ceiling Spectrum Analyzer Universal Radio Communication Tester Mobile Phone Relay Switch Unit Transmit Antenna Comm. Rx Ant on MAPS GPIB-Bus Fiber Optics for MAPS system MAPS Controller Submission 31 Stephen Berger, TEM Consulting

January 2004 doc. : IEEE 802. 11 -04/0092 r 1 Conclusion u u CTIA Over the Air Test Plan provides a repeatable measure of radiated performance of wireless devices. The results of this test are far better indicators of mobile station performance than current conducted power class measurements. Phones should be classified based on radiated performance, not conducted power. Near-field couplers and test boxes can be used in production environments to test entire radiated path when adjusting output power. Submission 32 Stephen Berger, TEM Consulting