C63-SC8

October 24, 2007

Gaithersburg Maryland

SC8 Members

• Joe Morrissey• Steve Berger• Don Heirman• Dan Hoolihan• Victor Kuczynski• Bob Hofmann• Steve Whitesell• Jim Turner• Steve Coston• Poul Anderson• Bob Jenkins• Bill Stumpf (???)

• Ed Hare• George Hirvela• David Zimmerman• Jag Nadakuduti• Dheena Moongilan• John Lichtig• Harry Levitt• Jeff Silberberg• Jon Casamento• Mike Windler• Herb Mertel• Werner Schaefer

• Matt Bakke• Paul Cardinal• Bob DeLisi• Bill Hurst• Ralph Showers• Mike Violette• Don Witters• Kendra Green• Daniel Ahlers• Massud Attaj

ANSI ACCREDITED STANDARDS COMMITTEE C63 ELECTROMAGNETIC COMPATIBILITY

SUBCOMMITTEE 8 – MEDICAL DEVICES AND EMC

Agenda for Wednesday, October 24, 2007

1. Opening and Self-Introductions

2. Review and Adoption of Proposed Agenda

3. Review and Adoption of Previous Meeting Minutes

4. Working Group Reports

4.1. WG#1 – Joe Morrissey - C63.18 4.1.1. Revised test protocol 4.1.2. MOTION: to send current draft to main committee for ballot (and

interest in participating in the ballot group) 4.2. WG#2 – Bob DeLisi – C63.21 4.3. WG#3 – Steve Berger – C63.19

4.3.1. Status of C63.19 (rev 2007, letter to FCC) 4.3.2. Overview of WG-3 meetings (Monday, Tuesday) 4.3.3. Status of 700 MHz Task Force 4.3.4. MOTION: to send PINS (700 MHz plan, any other issues) to main

committee for approval 4.3.5. Formation of a task group to address FCC request for comment

(assuming a request follows the WTB / OET recommendations)

1. Presentations 1.1. Overview of 700 MHz band (Dave Case)

1.1.1. Frequency allocations, rules of the road (per FCC R&O 5/27/07) 1.1.2. Anticipated technologies / modulations 1.1.3. Directions forward re: HAC and FCC needs 1.1.4. Current changes ANSI C63.19

1.2. GTEM vs. dipole testing for HA immunity (Tom Victorian / Gert Ravn) 1.3. Hearing aid distributions in the US (Joe Morrissey) 1.4. Mobile phone transmission patterns e.g., power control, DTx (Joe Morrissey) 1.5. NIDRR / Levitt / Gallaudet research update (Harry Levitt, Matt Bakke) 1.6. HEI research update – exposure systems (Jag Nadakuduti) 1.7. ATIS AISP.4 update (Jim Turner) 1.8. PINS-C item G: T-coil positions for testing (Jim Turner) 1.9. Other PINS-C items (open – and as time permits)

2. Liaison Reports / General Updates

2.1. ANSI ASC C63 SC2 (Definitions / C63.14) 2.2. ANSI ASC C63 SC3 (International Standard Harmonization) 2.3. IEC SC62A Maintenance Team 23 2.4. AAMI/EMC Committee Report 2.5. ISO TC215 (TR 21730, Health Canada Round Table, IEEE C95.1 / ICNIRP) 2.6. FDA Report 2.7. FCC Report 2.8. IEC/TC29 Electroacoustics, ISO/TC43 Acoustics [TC43/SC1 Noise]

3. New Business

3.1. SC3 membership (per e-mail – Bob Jenkins, Masud Attayi responded, procedures on web)

4. Next Meeting

ACTION ITEMS:

1. Joe Morrissey and Jag Nadakuduti to gather data on calculated and experimentally derived / simulated free space measurements for mobile phones that can be used as a look-up table / chart to estimate field strength in support of C63.18

2. Joe Morrissey to coordinate effort to get better definition on operational performance of mobile phones and hearing aids in support of C63.19: including:

a. DTx, specifically temporal characteristics and whether last full transmissions would overlap first incoming phonic sounds during listening phase

b. Dynamic power control, especially the normal operational performance of GSM phones in typical networks

c. Typical distance (separation) between nominal phone position and different classes of hearing aids

d. Percentage of different hearing aid types on the US market 3. Tom Victorian to supply Delta testing summary of hearing aid immunity and equivalent C63.19 M-

classification 4. Joe Morrissey to get with Steve Berger and recommend a document retention style and numbering

system – updated: Joe Morrissey to work with John Lichtig to define a structure for the entire C63 committee (all SCs) for retention on the C63 website

5. Joe Morrissey will send around list of definitions from C63.14 proposed to bee dropped (many are repetitions of IEEE STD100) [closed 4/12/07]

6. Joe Morrissey and Jag Nadakuduti to develop a look-up Table of free space measurements from mobile phones at full power to approximate field strength measurements for C63.18 / C63.24

7. Steve Berger to submit an FCC petition to adopt C63.19-2007 [closed 3/28/07] 8. Joe Morrissey to check with Dan Hoolihan regarding SC8 membership and dues [closed 3/28/07]

C63™ SC8 WG1 Report

ANSI C63.18: American National Standard - Recommended Practice for an On-Site, Ad Hoc Test Method for Estimating Electromagnetic Immunity of Medical Devices to Radiated Radio- Frequency (RF) Emissions from RF Transmitters

Major Revision: Optional Test Methods

• Representative waveforms• Recorded signal files• Actual RF transmitter (mobile phones in a

test mode / radio keyed to transmit)* Deleted: mobile phone taken to an area of

low signal to assume transmit at or near full power [dynamic power control makes it too variable to produce repeatable or reliable results]

Additional Revision

• Identifying local licensees• Obtaining proper permission / FCC STA• Look-up Table to estimate field strengths from

common RF transmitters (field probe surrogate)

RF Power (Watts) W 0.1 0.5 1 2 4 8RF Power (dBm) dBm 20.0 27.0 30.0 33.0 36.0 39.0

Dipole Radiator(assumed 2.4 dBi Gain)

Distance / Field Strength cm inches V/m V/m V/m V/m V/m V/m13.00 4.9 18.3 40.8 57.8 81.7 115.5 163.425.00 9.8 9.1 20.4 28.9 40.8 57.8 81.730.00 11.8 7.6 17.0 24.1 34.0 48.1 68.150.00 19.7 4.6 10.2 14.4 20.4 28.9 40.875.00 29.5 3.0 6.8 9.6 13.6 19.3 27.2100.00 39.4 2.3 5.1 7.2 10.2 14.4 20.4

Nominal Protection Distance V/m cm cm cm cm cm cm10.0 22.8 51.1 72.2 102.1 144.4 204.230.0 7.6 17.0 24.1 34.0 48.1 68.190.0 2.5 5.7 8.0 11.3 16.0 22.7

Chamber Measurements

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

0 0.5 1 1.5 2 2.5 3 3.5

Distance (in meters)

E-Fi

eld

(in V

/m)

iDEN (~200 mW)

AMPS (600 mW)

TDMA-800 (250 mW)

TDMA-1900 (250 mW)

GSM-900 (250 mW)

GSM-1800 (250 mW)

GSM-1900 (250 mW)

CDMA-800 (~630 mW)

CDMA-1900 (~630 mW)

Clause 3.3, 2nd par:

• From: "If there are metal Venetian blinds on the windows, they should be closed during the test."

• To “If there are metal Venetian blinds on the windows, they should be fully raised during the test. This is because prior testing has found …”

Section 3.7: RF field strength meterA field probe meter is suggested in the test methods above to characterize the ambient field levels from external sources as well as characterize E-field levels from the RF transmitter at any distances where EMI events are observed with the medical device under test. Several suitable field probes are available, and should include at a minimum a dynamic frequency range for detection starting at < 100 MHz to > 2GHz. Ranges that are greater than <100 MHz to > 2GHz, so long as the probe is calibrated to operate in the range where the RF transmitter will be operating. Probes that have a range only up to 1 GHz may be used for mobile phone signals in the 824-848 MHz band, as well as for many radio technologies that transmit below 1 GHz. The probe should be isotropic, and in addition have a sensitivity of at least 30 dB below the typical power of mobile phones and radios in the near field, or a sensitivity < 1-2 V/m. If the cost of purchasing a field strength meter is prohibitive, it may be possible to rent one or to pool resourses with another organization.

Table B.2—Typical transmitters, output power levels, and estimated field strengths at 1 m (39 in)

Product Frequency (MHz) Power (W) Field strength @ 1 m (V/m)

Paging transmitters 49 250 110 [i] Mobile radios 138–470 25 35a Hand-held transceivers 27, 49, 138–470 5 15a Police/ambulance 138–900 10–100 22–70a Commercial BW and Public Safety (mobile)

698-806 1-2

Wireless LANs 912, 2400, 5GHz 0.1 -0.25 2.2 – 3.1 Wireless personal digital assistants 896–940 2 10 Radio modems 896–901 10 22 Cellular telephones[ii] 800–900 0.6 5.4 Personal communications satellite telephones

1610–1626.5 1 7

Licensed PCS equipment 1850–1910 1 7 BWA (3G / IMT, WiMAX mobile) 2.5 -2.689 1-2 BWA (Fixed)) 3650-3700 1-25 Public Safety 4940-4990 2 CISPR 11, CISPR 22 [iii] 25–1000 0.04 10-6 0.0014 [iv]

[i] For these transmitters, 1 m (39 in) is in the near field. Therefore, these field strength estimates may be very inaccurate [ii] Global systems mobile (GSM) cellular telephones, particularly in Europe, may use higher power levels. [iii] Industrial, scientific, and medical (CISPR 11) devices that are not intentional emitters of RF and information technology

equipment (CISPR 22), each of which are in compliance with the respective emissions standard. [iv] This represents the approximate maximum RF field strength at a distance of 1 m (39 in) from this equipment.

C63™ SC8

Hearing Aid / Hearing Loss Distributions

0-9 %0-9 %10-19 %10-19 %20-24 %20-24 %25-29 %25-29 %30+ %30+ %

2002: Population > age 60

% of Populationover age 60

Source: United Nations “Population Aging 2002”

WW Average WW Average >> 60 = 10% 60 = 10%

0-9 %0-9 %10-19 %10-19 %20-24 %20-24 %25-29 %25-29 %30+ %30+ %

Source: United Nations “Population Aging 2002”

WW Average WW Average >> 60 = 21% 60 = 21%

% of Populationover age 60

2050: Population > age 60

Heterogeneity across Hearing Loss Types

• Hearing Loss– est. 28-35 million in US– est. 6 million / 20% wear HAs– 2% children <18– 60-75% adults >75– 60% of R&R Hall of Fame– Rate of hearing impairment in US

increasing faster than population

• Twenty percent of hearing loss patients use hearing aids

• Etiology– Noise 34%– Age 28%– Infection / Injury 17%– Genetics 5%– Other / unknown 16%

• Includes different magnitudes of loss, different sensitivity to parts of the audio spectrum, as well as increased background (e.g., tinnitus – objective or subjective)

• General Mechanism– Conductive (blockage)– Sensorineural (damage to inner ear /

acoustic nerves)– Mixed– Central Auditory Processing Disorder

• Examples– Acoustic Neuroma– Ototoxicity (drug induced)– Meniere’s Disease– Otosclerosis (bone abnormality)

Hearing Aid Compatibility

0

5

10

15

20

25

30

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

HAC

S/N

(d

B m

arg

in)Approach

HA distribution in the US

§ - HIA quarter statistics ending March 31, 2007 (Carol Rogan)† - Cathy van Evra‡ - Sergie Kochkin MarkeTrak publications (2004 data)newer BTE hearing aids have significantly increased immunity - ٭* - 30% ‡ ‡ - Kyle Dennis

HIA§ Delta† Kochkin‡ VA‡‡ AverageBTE 49% 44% 18% 38% 37%ITE 28% 31% 28% 48% 34%ITC 13% 14% 41% 10% 19%CIC 10% 11% 13% 4% 10%Total # 1,511 333,418

Table B.2—Typical transmitters, output power levels, and estimated field strengths at 1 m (39 in)

Product Frequency (MHz) Power (W) Field strength @ 1 m (V/m)

Paging transmitters 49 250 110 [i] Mobile radios 138–470 25 35a Hand-held transceivers 27, 49, 138–470 5 15a Police/ambulance 138–900 10–100 22–70a Commercial BW and Public Safety (mobile)

698-806 1-2

Wireless LANs 912, 2400, 5GHz 0.1 -0.25 2.2 – 3.1 Wireless personal digital assistants 896–940 2 10 Radio modems 896–901 10 22 Cellular telephones[ii] 800–900 0.6 5.4 Personal communications satellite telephones

1610–1626.5 1 7

Licensed PCS equipment 1850–1910 1 7 BWA (3G / IMT, WiMAX mobile) 2.5 -2.689 1-2 BWA (Fixed)) 3650-3700 1-25 Public Safety 4940-4990 2 CISPR 11, CISPR 22 [iii] 25–1000 0.04 10-6 0.0014 [iv]

C63™ SC8

Dynamic Power Control and Discontinuous Transmission

900 MHz band

control level power (dBm) power (watts) [calculated]5 33 2.00 2.00006 31 1.25 1.26197 29 0.80 0.79628 27 0.50 0.50249 25 0.30 0.3170

10 23 0.20 0.200011 21 0.12 0.126212 19 0.08 0.079613 17 0.05 0.050214 15 0.03 0.031715 13 0.02 0.0200

1800 and 1900 MHz Bands

control level power (dBm) power (watts) [calculated]0 30 1.00 1.00001 28 0.60 0.63102 26 0.40 0.39813 24 0.25 0.25124 22 0.16 0.15855 20 0.10 0.10006 18 0.06 0.06317 16 0.04 0.03988 14 0.025 0.02519 12 0.016 0.015810 10 0.010 0.010011 8 0.006 0.006312 6 0.004 0.004013 4 0.0025 0.002514 2 0.0016 0.001615 1 0.0010 0.0010

GSM Power Step IncrementsETSI Document, GSM 5.05 version 5.10, ETS 300 910, 1996

** new ETSI revision allows power control down to 5 dBm (0.003 W)

0.0001

0.001

0.01

0.1

1

0 50 100 150 200 250

Time (in seconds)

Lo

g P

ow

er (

in w

atts

)

Mobile Phone Transmit Power

[from Morrissey (2007), Rad Prot Dos]: Comparative power control levels associated with ~3 ½ minutes of two separate calls (in good vs. poor coverage) made on a US 1900 MHz GSM network. Peak (pulse) power can be calculated by multiplying maximal average power (125 milliwatts) x 8

*statistical models of path loss due too variable – must measure experimentally

Average Transmit Power

0.00

0.05

0.10

0.15

0.20

0.25

Ft.Lauderdale,

FL

Libertyville, Il ArlingtonHts, Il

Phoenix, Az Austin, TX Malaysia Germany France UK

Pow

er (w

atts

)Differences may reflect 850 / 1900 MHz vs. 900 / 1800 MHz network distributions, global roaming agreements, handoff characteristics (traffic management), indoor network deployments, driving habits, home use, etc

C63™ SC8

HEI Research Update

Mobile Phone Exposure

Kathrein panel antenna

http://kathrein-scala.com/catalog/800-10248.pdf

• Designed for in-building installations

• Multi band with high (1710-2500 MHz) and low (806-960 MHz) band antenna elements.

• Maximum input power: 50W

Kathrein multiband antenna

• high (1710-2500 MHz) and low (806-960 MHz) bandplexiglas casing for accurate positioning

High band antenna element

Low band antenna element

Field uniformity 1880 MHzseparation distance = 40mm and P=1W

E-field

0 dB = 140.0V/m

H-field

0 dB = 0.405A/m

Ongoing Antenna Design

Discone Antenna

Disc_radius = 20mm, Cone_length=110mm, Cone_outer_radius=35mm

(I forgot to take actual pictures of the antenna before shipping it to HEI)

Discone schematic

Discone antenna reflection coefficient

Discone Antenna reflection (dB)

-30

-25

-20

-15

-10

-5

0

0 500 1000 1500 2000 2500 3000

Frequency (MHz)

S11

(d

B)

E- and H-field data

  Distance outside cylindrical tube: 7mm 12mm 17mm

  Distance from top surface of discone: (20mm) (25mm) (30mm)

  POWER FREQUENCY        

E (V/m) 250mW 850 MHz 156.3 124.8 101.3

  1900 MHz 70.73 56.68 46.13

H (A/m) 250mW 850 MHz 0.0845 0.0744 0.0660

    1900 MHz   0.0776 0.0647 0.0553

Mobile Phone limits (V/m) from C63.19 (2006)

E- field Plots(12mm outside cylindrical tube)

850 MHz(70x70mm)

1900 MHz(70x70mm)

H- field Plots(12mm outside cylindrical tube)

850 MHz(70x70mm)

1900 MHz(90x90mm)