Telecommunications Industry Association
TR41.9.-15-08-005-MR1
Document Cover Sheet
Project Number
ANSI/TIA-PN-968-B-3
Document Title
G.Fast requirements for TIA-968-B
Source
Cisco Systems
Contact
Tim Lawler
170 West Tasman Dr.
San Jose, CA 95134
Distribution
TR-41.9
Intended Purpose
of Document
(Select one)
X
Phone: (408) 527-0681
Fax: (408) 853-3288
Email: tlawler@cisco.com
For Incorporation Into TIA Publication
For Information
Other (describe) -
The document to which this cover statement is attached is submitted to a Formulating Group or sub-element
thereof of the Telecommunications Industry Association (TIA) in accordance with the provisions of
Sections 3.3.2.2 through 3.3.2.4 inclusive of the TIA Engineering Committee Operating Procedures dated
May 2014, all of which provisions are hereby incorporated by reference.
Abstract
This contribution is a proposal for adding G.FAST profile 106 MHz requirements to a 3rd addendum to
TIA-968-B.
V2.1 – 20141205
Telecommunications Industry Association
3.2
TR41.9.-15-08-005-MR1
ACRONYMS & ABBREVIATIONS
G.FAST:
Fast Access to Subscriber Terminals
Annex C (informative) – Bibliography
C.11
ITU-T Recommendation G.9700 (2014), Fast access to subscriber terminals (FAST) –
Power spectral density specification.
5.3.10 G.FAST:
5.3.10.1 G.FAST signal power limitations:
5.3.10.1.1 The maximum aggregate upstream transmit power for G.FAST operating in the 106
MHz profile mode shall not exceed +4 dBm into 100 ohms.
5.3.10.1.2 The transmitted PSD for G.FAST shall not exceed the upstream PSD mask defined
in the table 68 (based on ITU-T Recommendation G.9700) for the G.FAST mode of
operation for which the modem is configured.
Table 68 defines the PSD masks for G.FAST Profile 106 MHz. Figure 68 shows these
requirements.
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Telecommunications Industry Association
TR41.9.-15-08-005-MR1
Table 68 – G.FAST profile 106 MHz PSD mask limits
Frequency band
PSD level (dBm/Hz)
across 100 ohms
RBW
0.2 kHz < f < 4 kHz
-97.5
100 Hz
4 kHz < f < 20 kHz
-97.5 to -90
1 kHz
20 kHz < f < 500 kHz
-90
10 kHz
500 kHz < f < 1825 kHz
-100
10 kHz
1825 kHz < f < 2 MHz
-100 to -80
10 kHz
(2 MHz + ½ × RBW) to (30 MHz – ½ × RBW)
-65
1 MHz
(30 MHz + ½ × RBW) to (106 MHz – ½ × RBW)
-73 to -76
1 MHz
106 MHz < f < 126 MHz
-76 to -110
100 kHz
126 MHz < f < 300 MHz
-110
100 kHz
NOTES:
1. The apparent gaps in the frequency band occur because they are the center frequencies
of the 1 MHz Resolution Bandwidth. The 1 MHz RBW covers the apparent gap between
center frequencies.
2. The least stringent limit applies at the frequency range boundaries.
5.3.10.1.3 The mask value to be compared against shall be the maximum value the mask takes
within a window [f − ½ × RBW, f + ½ × RBW].
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Telecommunications Industry Association
TR41.9.-15-08-005-MR1
Figure 68 – G.FAST profile 106 MHz PSD mask
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Telecommunications Industry Association
5.3.10.2
TR41.9.-15-08-005-MR1
The transverse balance for G.FAST terminal equipment shall equal or exceed the
values in figure 36 over the entire range of frequencies as defined in table 69. In
addition, G.FAST shall equal or exceed the minimum transverse balance
requirements for analog voice band equipment in 5.1.10. The metallic impedance
used for the transverse balance measurements for G.FAST shall be 100 ohms. The
metallic test voltage is 0.316V. Transverse balance testing is described in TIA TSB31-D. An illustrative test circuit for transverse balance conformance testing is shown
in figure 42. Testing is done with the TE transmitter turned off.
Table 69 – Frequency range for transverse balance requirements for G.FAST equipment
5.3.10.3
Frequency range
(MHz)
Longitudinal
termination
(RL) (ohms)
Metallic
termination
(RM) (ohms)
2 to 30
90
100
Limitations on equipment intended for operation on loop start telephone facilities.
Approved terminal equipment that operates over POTS shall conform to the
requirements in 5.1.11.2.
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