Francesco Carobolante Vice President Engineering Wireless Power Transfer Overcoming the Technological Hurdles
DISCLAIMER: The information provided in this presentation is for informational purposes only and is not intended to be, and should not be taken as or construed to be, legal and/or regulatory advice or recommendations. You should consult a lawyer or other advisor if you want professional assurance that the information in this presentation, and your interpretation of it, is accurate and/or appropriate to your particular situation. Any reliance upon any opinion, advice, statement, diagrams or information contained in this presentation shall be at your sole risk. Qualcomm Incorporated makes no representation, neither expressly nor impliedly, as to the accuracy, completeness, timeliness or reliability of the materials or any information contained in this presentation.
Wireless power has a long history 1901: Resonant Magnetic Induction 1902: Wireless Energy Transmission
Convenience Wireless Charging Landscape Long Range: Far-field RF Short to Medium Range: Near Field Resonance Coupling of RF energy to a device with a small receiver antenna with device in the RF far field Device is brought within near field of a low frequency TX antenna. RF energy couples to device with small receive antenna where it is rectified for device charging Short Range: Inductive Coupling Zero Range: Conductive Mat Coupling of RF energy when a device with a small receive antenna is placed on a charging surface containing the transmit elements Current flows through the pad to a conductive adapter in the device
General Wireless Power Transfer Model (multiple receivers) Harmonic Filter Rectifier & Regulator Oscillator & Driver Harmonic Filter Coupled Coils Subsystem Harmonic Filter Rectifier & Regulator
Overcoming the Technological Hurdles Use Case Regulatory Standardization Commercial Readiness
Overcoming the Technological Hurdles Use Case Regulatory Standardization Commercial Readiness
Wireless Power Needs to Support Simultaneous Charging of Multiple Devices and Types Preferred Number of Devices to Be Simultaneously Charged Multiple Devices Single Device Mobile Phone Digital Camera Laptop MP3 Music Player Bluetooth Headset Smartphone Handheld Game Camcorder Portable Portable Media Portable DVD Playe Mobile Internet Portable Satellite Netbook UMPC 2% 1% 4% 3% Devices Likely to Buy and Use with Wireless Charging 12% 12% 11% 11% 13% 18% 25% 34% 34% 0% 10% 20% 30% 40% 50% 60% 70% 80% 45% 74% Source: Qualcomm omnibus survey: Base: US Consumers Who Own Traditional Mobile Phone or Smartphone and Are At Least Somewhat Interested in the Wireless Charging Concept (n=657 and n=483)
Flexible Coupling A Truly Universal Solution NOT specific to device type No need to specify location No alignment required
A4WP Technologies Clear the 1st Hurdle Meets Consumers Use Case Requirements Use Case Delivers Spatial Freedom X/Y Placement Benefit: Plenty of Room for up to 3 smartphones or a single tablet Simultaneously Delivers Z Freedom Benefit: Users can charge seamlessly in all environments Multi-Device Charging Multi-Device Type Charging
Overcoming the Technological Hurdles Use Case Regulatory Standardization Commercial Readiness
Human Exposure Limits FCC 1 limit of 1.6 W/kg on 1g SAR 2 to prevent tissue heating for f > 100 khz ICNIRP 3 1998 and 2010 standards for induced current density (J) and induced electric field (E) between 1 Hz and 10 MHz to prevent nerve stimulation in both central and peripheral nervous systems (CNS and PNS) 2010 standard specifies the E limits for both CNS and PNS 1998 standard was based on effects seen in CNS from biological studies but specifies the induced J limits for all tissues in head and trunk regions As of today, ICNIRP 2010 standard has not been adopted by regulatory bodies. Hence, human exposure should be qualified for all exposure quantities in 100 khz to 10 MHz frequency range: 1 Federal Communications Committee 2 Specific Absorption Rate 3 International Commission on Non-Ionizing Radiation Protection
Exposure Estimation for Embedded Desktop Module A simulation methodology is necessary to assess RF exposure with respect to ICNIRP basic restrictions Numerous wireless power uses cases have been evaluated by Qualcomm to determine whether the regulatory requirements can be achieved. A few examples are as follows: Next to a tray placed on a table Next to a nightstand Working at a desk with embedded TX Hands on a driving wheel A hand on driving wheel and the other near a gear shift Each use case evaluated show results below the regulatory requirements 6.8 AT rms corresponds to 25 W of power transferred to the load in the embedded system. For the same load, 37 W of power can be delivered when the worst case reaches the exposure limit.
E-field (dbuv/m) H-field (dbua/m) Regulatory Emissions Requirements Radiated emissions assessment per FCC Pt.15/18 US limits Radiated emissions assessment per CISPR 1 11 Int l limits for ISM Equipment Emission comparison with FCC limits Emission comparison with CISPR 11 limits 80 70 Limits @300m Unrestricted limit at ISM 6.78MHz Limit @30m 70 60 468kHz, H=60.50 Unrestricted limit at ISM 6.78MHz 60 50 40 FCC Pt.15 limit FCC Pt.18 limit RE of charging at 468kHz RE of charging at 6.78MHz 50 40 6.78MHz, H=54.07 30 30 20 6.78MHz, E=73.02 20 CISPR11 G2B limit@3m 10 468kHz, E=8.3 0 0.10 1.00 10.00 Frequency (MHz) 10 CISPR 11 cooker limit@3m RE of charging at 468kHz RE of charging at 6.78MHz 0 0.10 1.00 10.00 Frequency (MHz) Both the Low frequency solution (468KHz) and The higher frequency solution (6.78MHz) for the desired use case meet the FCC requirements 1 Comité International Spécial des Perturbations Radioélectriques Low frequency solution (468KHz) for the desired use case does not meet the CISPR 11 requirements The higher frequency solution (6.78MHz) for the desired use case meets the CISPR11 requirement
A4WP Technologies Clear the 2nd Hurdle: Regulatory Requirements Regulatory Wireless Power Compliance Regulatory categorization depends on frequency of operation and signaling approach ISM or other category of equipment Frequency selection is critical to ensure compliance with radiated emissions limits Wireless power compliance with RF exposure should be assessed using Basic Restrictions Dependency on frequency, power, loop geometry and use case definition Regulators currently assessing wireless power and applicability of existing rules
Overcoming the Technological Hurdles Use Case Regulatory Standardization Commercial Readiness
Alliance for Wireless Power A Path to Standardization Purpose Vision Enable a global wireless power transfer ecosystem based on a non-radiative, near-field magnetic resonance approach Deliver Wireless Power Transfer (WPT) spatial freedom Be the primary venue supporting the evolution of wireless power transfer technologies, products and services based on a non-radiative, near-field magnetic resonance approach Mission Global standardization Certification and testing Regulatory compliance and policy
Open System Many Opportunities for Innovation and Differentiation 2.4GHz Comm AC Filters Amplifier Drivers Processor Converters Sense Communication Z IN_TX Z IN_TX + V TX - I TX Z21 Resonator Z IN_RX + V RX - Z IN_RX Filter Rectifier Processor Converter Sense Communication Only key interfaces are constrained
Alliance for Wireless Power Ecosystem Membership 38 Automotive Carrier Consumer Devices Components Furniture Technology Design, Test & Certification
A4WP Technologies Clear the 3rd Hurdle: Standardization Requirements Standardization The technical working committee has been established Responsible to develop, maintain and execute the A4WP Technical Program focused on the development and maintenance of a Wireless Power Transfer Technical Specification The baseline system specification has been APPROVED and released to the membership The following committees have also been established: Certification Working Committee Regulatory Working Committee Marketing Working Committee
Overcoming the Technological Hurdles Use Case Regulatory Standardization Commercial Readiness
Technology Meeting Commercial Readiness Meeting the needs of the Smartphone is a key driver for the wireless power market to achieve its potential 74% of questioned Smartphone users are likely to buy and use wireless charging 1 Some of the Keys to Smartphone Adoption: Meeting the use case described earlier Meeting charge time, touch and battery temperature requirements Meeting radio coexistence requirements Ensuring metal objects in or near the field do not have a significant temperature rise 1 Source: Qualcomm omnibus survey
Meeting Charge Time, Battery, and Touch Temperature Requirements Performance relative to a wired charger Charge power (% of wired charger Power) WiPower Receiver Multicharger Commercially Available WPT Solution 73% 57% % of Max outside case temp. spec. % of Max touchscreen temp. Spec % of Max battery temp. Spec. Time to charge termination (% of wired charger time) 96% 81% 76% Not measured 76% 82% 119% 150% A4WP-compatible Technologies Meet Charge Time, Battery, and Touch Temperature Requirements Based on Commercial Benchmarks
Meeting Radio Coexistence Requirement: WWAN (GSM, CDMA, LTE, etc.), GPS, Wi-Fi, Bluetooth, and NFC Qualcomm has over 25 years experience ensuring radio coexistence Qualcomm Regulatory team performs link budget analysis to characterize degradation due to noise and isolation/ rejection needed per design Coexistence is addressed at the implementation level with OEMs
WWAN Coexistence Reference Specs Applications TIS 1 Specs for Phone by Carriers CDMA 850 Spec. Provided, [1] CDMA 1900 Spec. Provided, [2] TIS Specs by UE Vendors or Std GSM 850 Spec. Provided, [3] Spec. Provided, [4] GSM 900 Spec. Provided, [3] Spec. Provided, [4] GSM 1800/1900 Spec. Provided, [3] Spec. Provided, [4] UMTS 2100 Spec. Provided, [3] Spec. Provided, [5] GPS WLAN Spec. Provided, Spec. Provided, based on data rate [7] OEM Specs for Degradation by Accessory Spec. Provided,[6] Spec. Provided,[6] Spec. Provided,[6] Spec. Provided,[6] Spec. Provided,[6] Spec. Provided,[6] Derived Min TIS Due to Interference by WiPower Spec. Provided, Spec. Provided, Spec. Provided, Spec. Provided, Spec. Provided, Spec. Provided, Source Docs [1] Carrier 1 specs [2] Carrier 2 specs [3] Carrier 3 specs [4] 3GPP TSG RAN WG4-#52 [5] GSMA SE.43 v3.0 [6] XX OEM accessory specs [7] 802.11x standard BT Spec. Provided, [8] [8] BT RF Specs 1 TIS = Total isotropic sensitivity (average over the whole sphere)
Example of Test Results and Design Guidance Platform Device 1 Device 2 Technology and Band Worst Position Highest EISmin (dbm) % Delta Margin (db) to Derived Spec. (assuming 3dBi antenna gain) CDMA BC0 4 Spec Provided 1.7% CDMA BC 1 7 Spec Provided 0.3% CDMA BC 0 4 Spec Provided 1.2% CDMA BC1 1 Spec Provided 0.2% : only one position was checked for Device 2 The radiated performance is device specific. Below highlights the guidance for performance improvement Noise sources Harmonics from Tx (amplifier) Harmonics from Rx (rectifier) Mitigation solution Low-pass filter at PA output Isolation between Tx coil and WWAN antenna EMI filter between Rx coil and rectifier Isolation between Rx coil and WWAN antenna
Ensuring Metal Objects in or Near the Field Do Not Have a Significant Temperature Rise Expected Variation in Induced Power Losses Across Frequency Wireless Charging Solutions Operating in the 100s of KHz Range Generate ~10x the Amount of Induced Power in Foreign Objects as That of 6.78 MHz Systems
A4WP Technologies Clear the 4th Hurdle: Commercial Readiness Requirements Commercial Readiness Evaluation platforms have demonstrated that the technology can Meet the charge time, touch and battery temperature requirements Meet radio coexistence requirements Deliver a SPATIAL FREEDOM use case while ensuring objects in or near the field do not have a significant temperature rise
Overcoming the Technological Hurdles to Drive Wireless Power into the Mainstream Wireless Power Selection Checklist Meets Use Case Requirements Meets Regulatory Requirements Meets Standardization Requirements Meets Commercial Readiness Requirements Delivers Spatial Freedom (Simultaneously meeting X/Y and Z) Simultaneous charging of multiple devices Simultaneous charging of multiple device types ICNIRP FCC Part 15/18 Charge Time, Touch and Battery Temperature Requirements Mobile Phone Coexistence Minimal temperature rise in foreign objects in or near the field A4WP
Overcoming the Hurdles to Drive Wireless Power into the Mainstream Mainstream Use Case Regulatory Standardization Commercial Readiness
Thank you Follow us on: For more information on Qualcomm, visit us at: www.qualcomm.com & www.qualcomm.com/blog Qualcomm is a trademark of Qualcomm Incorporated, registered in the United States and other countries. Other products and brand names may be trademarks or registered trademarks of their respective owners