Jun 20, 2022 1 Ad-hoc workgroup report on New Technologies TC-34 ad-hoc taskgroup Chair : David Case
Dec 16, 2015
Apr 18, 2023 1
Ad-hoc workgroup report on New Technologies
TC-34 ad-hoc taskgroup
Chair : David Case
Apr 18, 2023 2
Overview
This is report provides an overview of the current generation of technologies as well the SAR test procedures from the FCC to evaluate these product compliance.
This discussion was to provide information for the TC34 and TC 106 workgroups to consider SAR measurement difficulties for today’s technology and to prepare for the next revision of the IEEE 1528 / EN 62209.2 standards.
The technologies addressed in this discussion are Wi-Fi, WiMAX, 3G as well as discussion on the FCC test guidelines for laptops
Apr 18, 2023 3
802.11 a/b/g/n bands
Bandwidths for DTS 20 MHz, 40 MHz
FH BW <1MHz to <5MHz
Transmitter power based on FCC or ETSI rules.
Frequency TX power Max EIRP
2400-2483.5MHz 1W 4W EIRP*
5150-5250 MHz 50mW 200mW EIRP
5250-5350 MHz 250mW 1W EIRP**
5470-5725MHz 250mW 1W EIRP
5725 – 5850MHZ 1W 4W EIRP
* ETSI max is 100mW EIRP
**ETSI Max is 200mW EIRP
Apr 18, 2023 4
802.11 based devices
Frequency 4940- 4990 MHz Public Safety Transmitter power +20dBm +33dBm non 802.11
BW Low TX power High TX
1MHz +7dBm +20dBm
5 MHz +14dBm +27dBm
10MHz +17dBm +30dBm
15MHz +18.8dBm +31.8dBm
20MHz +20dBm +33dBm
Apr 18, 2023 5
802.11Technical info
802.11b/g modulations BPSK, QPSK, QAM, CCK , OFDM
Data Rates 1- 54Mbps
802.11a modulations BPSK, QPSK, OFDM
Data Rates 6 – 54Mbps
802.11n OFDM
Modulations to 108Mbps
4.9GHz OFDM
Proprietary turbo, half and quarter rate modes
Switched diversity antenna capability
Operating modes – ad-hoc and infrastructure
Dynamic communication protocols (varying power and Tx duty factor)
Module transmitters
Apr 18, 2023 6
802.11 Issues
Normal operating modes unsuitable for SAR testing
Test modes do not accurately reflect real operation modes
SAR of switched antenna diversity cannot easily be measured
Other complex antennas require additional SAR evaluation
Transmit duty cycle during normal use varies usage and traffic conditions.
Burst duty factor and burst crest factor corrections are random, compensation difficult.
Modules can be used in variety of hosts with different antenna configurations , making testing of stand alone modules more difficult to simulate results in variety of hosts.
Apr 18, 2023 7
802.11 SAR Test Recommendations
Test with transmitter set at highest output power for each modulation chosen.
Until duty cycle issue is resolved test at 100% duty cycle understanding that in normal operation duty factor could be greatly reduced.
Consider verifying output linearity and duty cycle
Lowest data transfer rate typically uses lower order modulation that require higher average output power but may need to verify SAR for higher order modulations according to output power requirements.
Apr 18, 2023 8
802.11 SAR Test Recommendations
Test at least one high order (OFDM) and one low order modulation (BPSK). If the maximum average TX power is more than 0.25dB higher for other modulations, additional testing of other modulations may be required
Testing of additional BW can be done according to the output power requirements for the various Bandwidths..
Radio modules will require appropriate host platforms to conduct SAR tests : example laptop, PDA, etc for use as such platforms.
Apr 18, 2023 9
Summary
802.11 devices are becoming more pre valiant as standard equipment in devices such as wireless phones, laptops, handheld.
802.11 devices are not just for use in the unlicensed band but now are being designed and deployed for licensed services as well.
FCC 802.11 SAR test procedure needs to be reviewed by the TC 34 committee to consider incorporating some of the requirements.
Apr 18, 2023 10
FCC 3G Document
Apr 18, 2023 11
Introduction to WWAN SAR
3 main WWAN technologies dominate international markets: GSM, CDMA, WCDMA
Devices must be configured in an appropriately and consistent manners Configurations must have acceptable PAR within SAR measurement equipment
capabilities Configurations must be repeatable
WWAN technologies are complicated, but fortunately wireless standards committees have test configurations that can be utilized for SAR testing
FCC has released guidelines for SAR testing in reference to US requirements
FCC documents can be referenced to create IEEE documents specifying technology configurations required for SAR testing
Apr 18, 2023 12
Dominant WWAN Parameters Impacting SAR
Peak to Average (PAR) Impact: PAR vs Probe linear response impacts SAR results accuracy WWAN waveforms have PAR ranging from 1 dB to >5dB Solution: Identify low PAR waveforms and mandate for SAR testing
Channel Configurations Impact: Channel configuration can impact maximum output power and PAR Variety of baseband physical channel types/configurations summed together and frequency up-converted to
generate mobile transmit signal Some channel configurations result in transmit power reduction defined by WWAN standards (ie high data
rate configuration could reduce TX power to meet emissions requirements) Solution: Mandate channel configurations that achieve maximum output power with low PAR
Configuring for max power Impact: Mobile device may not be configured to transmit maximum power Different WWAN technologies have different procedures to configure mobile devices to transmit at max power Solution: Identify methods for configuring technologies for maximum output power and identify any
problematic configurations/procedures
Transmitter Modulations Impact: Effects PAR Different technologies incorporate different modulations for the mobile transmitter Solution: Identifying channel configurations with low PAR and consistent modulation schemes
Apr 18, 2023 13
WWAN Technology Summary
Class Technology Usage Notes Typical Portable Max Power (Avg detector)Transmitter Modulations
(Uplink/Reverse link) Industry Test StandardsAddressed in FCC 3G
Procedures
WCDMA (3G)
WCDMA (R99) Primarily voice, limited data 400mW BPSK 3GPP TS 34.121 Yes
WCDMA HSDPA (Release 5) Enhanced downlink data 400mW BPSK 3GPP TS 34.121 Yes
WCDMA HSUPA (Release 6) Enhanced uplink data 400mW BPSK 3GPP TS 34.121 Yes
CDMA (3G)
CDMA 1x Primarily voice, limited data 400mW QPSK, BPSK 3GPP2 C.S0011-C Yes
CDMA DO Release 0 Enhanced downlink data 400mW QPSK, BPSK, 16QAM
3GPP2
YesC.S0033
CDMA DO Revision A Enhanced uplink data 400mW QPSK, BPSK, 16QAM
3GPP2
YesC.S0033
GSM (2G)
GSM Primarily voice 250mW GMSK 3GPP No
GPRS Data 500-1000mW GMSK 3GPP No
EDGE (EGPRS) Data 250mW 8PSK 3GPP No
LTE OFDMA TBD TBD BPSK, QPSK, QAM, TBD 3GPP No
UMB OFDMA TBD TBD BPSK, QPSK, QAM, TBD 3GPP2 No
Apr 18, 2023 14
FCC 3G Document Status
Current FCC 3G Document defines CDMA/WCDMA test practices currently used by industry Document defines test modes used for RF safety testing Guidelines leverage from test modes defined by 3GPP and 3GPP2
standards bodies Release of document has helped to bring consistency to WWAN SAR
reports
Document needs some subtle changes to extend applicability of the document to future devices Modification topics for discussion are in the following slides
Apr 18, 2023 15
International WWAN Bands
Band Name3GPP (CDMA) Operating Bands per
C.S00573GPP (WCDMA) Operating Bands per TS
25.101Mobile Transmit Frequencies Base Station Transmit Frequencies
450 MHz Band Class 5 452-484 MHz 462-494 MHz
700 MHz Band Class 7 776-794 MHz 746-764 MHz
800MHz Cell Band Class 0 V
824 - 849 MHz 869-894 MHz
900MHz Band Class 9 VIII 880 - 915 MHz 925 - 960 MHz
Japan Band Class 3 887-925 MHz 943-870 MHz
DCS Band Class 8 III 1710-1785 MHz 1805-1880 MHz
AWS Band Class 15 IV
1710-1755 MHz 2110-2155 MHz
PCS Band Class 1 II 1850 -1910 MHz 1930 -1990 MHz
2 GHz IMT-2000 band Band Class 6 I 1920 - 1980 MHz 2110 -2170 MHz
2.5 Band Class 13 VII 2500-2570 MHz 2620-2690 MHz
Apr 18, 2023 16
Addressing Configuration Requirements
WWAN standards identify channel configurations and procedures for configuring devices for RF conformance testing Standards define many different configurations for diverse set of RF tests.
• Max power and emissions test configurations can be used for SAR testing• Only a subset (or just one configuration) is applicable to SAR testing
Standards define procedures for configuring device to transmit at max power• WWAN power control schemes make configurations for maximum power easy
FCC’s 3G document has identified technologies configurations required FCC SAR testing based on the industry standards
FCC 3G document can be leveraged upon to generate IEEE configuration guidance document
Apr 18, 2023 17
Suggested Modifications (3G Document)
Add some verbiage for multi mode devices (CDMA + GSM/GPRS/EDGE + WCDMA) limiting test data to highest TX power modes.
Increase power variance between modes beyond 0.25 dB to determine additional SAR test requirements if >75% margin
0.25 dB is within the measurement error of test equipment
Address test software vs. call box call support
Apr 18, 2023 18
Suggested Modifications (3G Document) Continued
Add some commentary about simultaneous TX (BT, WLAN)
Add tables with standards references
Change 1x RC3 reference to be consistently SO55 (remove TDSO/S32)
Refine appendix information Reduce and clarify existing information
Apr 18, 2023 19
FCC Notebook SAR Evaluation
Apr 18, 2023 20
Introduction
Current SAR measurement procedures applicable to handset designs
Future/current wireless devices include embedded Notebook computers, Ultra Mobile PCs, cameras, TBD consumer electronic devices No test measurement procedures exist
Future devices incorporating wireless transmitters is limitless and thus difficult to establish procedures
Apr 18, 2023 21
Problem Statements
Absence of non-handset SAR procedures is causing problems for the wireless product industry
Wireless Industry has requirements for two types of guidance: Measurement procedures for non-handset devices Test requirements for devices with multiple technologies
These devices are in the market today, so these procedures need to be addressed quickly Industry currently completes a large number of burdensome SAR
test cases that result in very low SAR results (>10dB of margin)
Apr 18, 2023 22
Factors for Consideration
Separation Distance from user: Some devices provide separation distance from user such that SAR testing may not be applicable Is SAR really necessary for a 500mW transmitter with 10cm of
separation distance?
Simultaneous transmission of multiple technologies: How does simultaneous transmission impact RF safety? Depending on the separation distances and transmit power, SAR
testing may not be applicable• If antennas are shared, separation distance to user must be
considered• If different antennas, the separation distance between the antennas
and the interaction between the antennas must be considered
Apr 18, 2023 23
FCC Notebook Document
Released by FCC in Dec 2007 Allows reduction in SAR test requirements depending on TX
power and separation distances Reduces test requirements for changes/variations in similar
notebook models
Excellent first step in identify ways to reduce unnecessary testing Current document only applies to very low power applications
Future work required to further reduce test cases
Apr 18, 2023 24
Discussion points for Notebook Document
Need further discussion on antenna to antenna separation distances as they relate to impact on SAR measurement results Support simulations? Compare simulations with actual SAR measurement of notebook
computers
Need further discussion on antenna to user separation distance At what distance does SAR measurement become negligible vs.
FCC and international SAR limits Use test data of SAR measurements on actual notebook
computer products as part of the equation
Apr 18, 2023 25
Summary
Wireless transmitters are being incorporated into a diverse type of form factor end product
Guidelines defining test procedures are required to address RF safety testing
Future work is required to expand on FCC’s first attempt to address the test procedures and establish industry wide test practices
Apr 18, 2023 26
SAR Test Complexities with WiMAX
Apr 18, 2023 27
WiMAX Forum 802.16e Bands
OFDMA Signal with different FFT sizes and modulations available
Multiple Bandwidths Supported (5, 7, 8.75, 10 MHz & future may include 20 MHz)
Transmitter power based Device Power Class and Open loop and Closed Loop rules. Typical range 24 – 33 dBm
Frequency Chn BW(MHz) FFT Size
2.3 – 2.4 GHz 5, 8.75, 10 512, 1024, 1024
2.496-2.69GHz 5,10(both must be supported) 512, 1024
3.3 – 3.4 GHz 5, 7, 10 512, 1024, 1024
3.4 – 3.8 GHz 5, 7, 10 512, 1024, 1024
Apr 18, 2023 28
Dominant WiMAX Parameters Impacting SAR
Frame Configurations & Peak to Average (PAR) Impact: Frame configuration can impact maximum output power and PAR Variety of modulations, flexible allocation of number of sub-carriers in FFT, different coding
available for each sub-carrier, flexible duty cycle. Solution: Mandate frame configurations that achieve maximum output power with low PAR
Configuring for max power Impact: Mobile device may not be configured to transmit maximum power Lack of loop back testmode makes confirmation of power and frame control difficult. Test
equipment with required level of frame and power control is still under development. Solution: Identify methods for configuring technologies for maximum output power and identify
any problematic configurations/procedures
Apr 18, 2023 29
Other Issues Impacting SAR Measurements of WiMAX DUT
Current Probe Calibration methods may not address complexity of WiMAX signals.
Power measurement profiles on current equipment may not sense the frame correctly and miss the edges. New profiles or equipment may be needed.
Apr 18, 2023 30
MIMO Technologies
Apr 18, 2023 31
MIMO In Various Market
802.11n- WLAN
802.16 – WWAN
High Speed Downlink Packet Access (HSDPA) for W-CDMA UMTS (3GPP TS25-876): 28 Mbps peak rates in 5 MHz channel
4MIMO-OFDM strong candidate for 4G systems: under investigation by 4G Mobile Forum and Wireless World Research Forum
(source: Qualcomm MIMO presentation @TCBC workshop)
Apr 18, 2023 32
MIMO Technologies
MIMO = Multiple-In; Multiple-Out MIMO requires signal processing on transmitter and receiver
Multiple-In= Multiple Receiver Chains
Multiple-Out=Multiple Transmitter Chains
Chains= No. of RX or TX elements
2x3 MIMO= 2 Transmitter chains and 3 receiver chains.
2x2 MIMO= 2 Transmitter chains and 2 receiver chains.
Apr 18, 2023 33
MIMO Technologies
MISO: Multiple-In (Multiple Receiver Chain); Single-Out (Single Transmitter Chain) SISO: Single-In (One Receiver Chain); Single-Out (One Transmitter Chain) CDD/ Legacy: Cyclic Delay Diversity: only applicable to OFDM (Orthogonal Frequency Division
Multiplexing) modulation (802.11g and/or 802.11a)- 802.11b does not use OFDM modulation (CCK, DQPSK, DBPSK).
CDD/ Legacy: can increase frequency selectivity of the channel seen by the receiver, which results in cyclic delay diversity (CDD) and achieves spatial diversity.
STBC/Legacy : Space-Time Blocked Coding: to improve bit error performance of the whole wireless system
SDM/MIMO: Spatial Division Multiplexing : SDM spatially multiplexes multiple independent data streams, transferred simultaneously within one spectral channel of bandwidth. MIMO SDM can significantly increase data throughput as the number of resolved spatial data streams is increased.
Apr 18, 2023 34
MIMO Antenna Locations
Apr 18, 2023 35
MIMO Antenna Locations
Apr 18, 2023 36
MIMO Power
802.11b average power is higher than 802.11g legacy or 802.11g/40MHz (approxi. 3dB higher)
TX chain#0 and chain#2 average output power is within 0.5 dB
TX chain#0 and chain#2 peak output power is within 1 dB.
Apr 18, 2023 37
MIMO Output Power
2.4GH
z Band
Apr 18, 2023 38
MIMO Power
Proposed 802.11 WORST-CASE CONFIGURATION AND MODE (based upon measurement)
802.11b mode, 20 MHz Channel Bandwidth, 1 Mb/s, CCK Modulation 802.11g mode, 20 MHz Channel Bandwidth, 6 Mb/s, OFDM Modulation,
Spatial Stream 1.(SAR is not required when the max. average output power is less than ¼ dB higher than the corresponding 802.11b channel)
802.11a mode, 20 MHz Channel Bandwidth, 6 Mb/s, OFDM Modulation, Spatial Stream 1.
802.11n HT20 mode, 20 MHz Channel Bandwidth, MCS0, 6.5 Mb/s, OFDM Modulation, Spatial Stream 1.
802.11n HT40 mode, 40 MHz Channel Bandwidth, MCS0, 13.5 Mb/s, OFDM Modulation, Spatial Stream 1.
Apr 18, 2023 39
MIMO Summary
Shall average output power measure with combiner? Or on individual TX chain?
Shall MIMO device be measured with both transmitting chains-ON or individual TX chain is enough?
Test Software provided can configure MIMO to transmit on one of chain or all chains simultaneously
When one of TX chain antenna is portable (<20cm) and the other TX chain antenna is mobile (>20cm), test mode shall be defined.
Apr 18, 2023 40
New Taskgroup issues
Provide information on test procedure used to determine worst case modes for 802.11.
Develop plan for additional verification of proposed 802.11 modes SAR test requirements –
Develop plan for addressing WWAN / WiMAX technologies issues for SAR test standard.
Develop plan to start addressing non handheld devices with multiple radios
Recommendations for above due by April TC34 conference call.