TIA-1083 Wireline TelephoneHAC Performance Requirements

With a Comparison toC-63.19 Wireless Telephone

HAC Magnetic Performance Requirements

2

ANSI/TIA-1083-2007 Telecommunications – Telephone

Terminal Equipment – Handset Magnetic Measurement Procedures and Performance Requirements

Approved March 21, 2007 Developed by TIA TR-41.3, Analog and

Digital Wireline Terminals

3

Overview Addresses magnetic interference issues

identified by hearing aid users. RF interference does not appear to be a

significant issue for cordless telephones.

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Requirements Summary Signal Sensitivity:

-22 dB (A/m) at 1000 Hz, Perpendicular -27 dB (A/m) at 1000 Hz, Transverse• Same as Part 68, but greater latitude allowed in

measurement location. Harmonic Distortion:

10%, Perpendicular and Transverse Frequency Response:

• Same as Part 68 and C63.19, Perpendicular.

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Requirements Summary (cont)

A-Weighted Noise: -40 dB (A/m), Perpendicular and Transverse• Measured same as in C63.19 using half-band

integrator.

Signal-to-Noise Ratio: 45 dB, Perpendicular and Transverse• Approximately equivalent to 30 dB requirement

for C63.19.

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Requirements Summary (cont)

Signal-to-Noise Ratio (cont)• Noise is measured same way for both standards.• Signal in C63.19 represents “nominal level

speech input” (see Footnote 45).• Signal in TIA-1083 is same as in Part 68 and is

“approximately 15 dB above the average level” (see paragraph 2.4 in EIA RS-504 as reproduced in 47 CFR 68.316).

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Perpendicular Measurement

Measurement Plane

Handset Side Profile

PerpendicularProbe

locationexample

10mm

10mm

ApplicablePerpendicularMeasurementPosition Area

ReferenceAxis

Width ofHandsetHandset Front Profile

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Transverse Measurement

Measurement Plane

Handset Side Profile

Transverse Probelocation example

10mm

10mm

ApplicableTransverse

MeasurementPosition Area

ReferenceAxis

Width ofHandsetHandset Front Profile

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2005 SHHH Cordless StudyT-Coil Interference Avg Score vs Noise (dBA/m)

-1

0

1

2

3

4

5

1 2 3 4 5 6 7 8 9

Sample

Av

g S

co

re

-72

-62

-52

-42

-32

-22

-12

No

ise

(dB

A/m

)

Avg Score

dBA/m

Unbearable

Very Annoying

Annoying

Mildly Annoying

Not Annoying

No Interference

Figure C.3 from TIA-1083

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2006 HLAA Parametric Study

Figure D.3 from TIA-1083

Minimum S/N for a "Normal Use" Rating

0

10

20

30

40

50

0% 20% 40% 60% 80% 100%

subjects meeting criteria

S/N

- d

B DSSS

FHSS

Display

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RF Interference ??

Informal FCC Complaints received by cordless telephone manufacturers were from T-coil users.

RF power level typically 200 mW. 2005 SHHH Cordless Study included 27

people who used T-coil coupling and 5 who used acoustic coupling to the microphone.

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2005 SHHH Cordless Study

T-Coil and Microphone Interference Avg Score

-1

0

1

2

3

4

5

1 2 3 4 5 6 7 8 9

Sample

Av

g S

co

re

Avg Score

Mic Avg

Unbearable

Very Annoying

Annoying

Mildly Annoying

Not Annoying

No Interference

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Contact Information

Stephen R WhitesellTIA Representative to C63Chair, TIA TR-41Senior Technical ConsultantStandards, Regulatory and Intellectual Property MattersVTech CommunicationsTel: 732 751 1079Email: swhitesell@vtech.ca