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**Carol W. Wilner** Suite 1000

Vice President, Executive Branch Advocacy 1120 20th Street NW

Federal Government Affairs Washington, D.C. 20036

202 457-7435

FAX 202 457-3051

EMAIL cwilner@att.com

February 10, 2004

Ms. Kathy Smith

Chief Counsel

Office of the Chief Counsel

National Telecommunications and

Information Administration

U.S. Department of Commerce

Room 4713

1401 Constitution Avenue, N.W.

Washington, DC 20230

> Re: [Rural Wireless Broadband Access in the 3650-3700 MHz Band, Docket
> No. 040116021-4021-01D]{.underline}

Dear Ms. Smith:

In response to the Federal Register notice published January 28, 2004,
AT&T Corp. ("AT&T") submits these comments in the above-entitled Notice
of Inquiry. AT&T supports efforts to develop alternative means of
accessing customers -- for both narrowband and broadband services -- and
supports the proposed opening of spectrum for use by unlicensed devices,
provided that means are established to prevent harmful interference to
AT&T's C-band satellite earth stations.

As noted in AT&T's comments to the Federal Communications Commission,
filed April 17, 2003 in ET Docket No. 02-380, AT&T operates satellite
earth stations, some of which are licensed to operate in the Extended-C
band (*i.e.*, 3650-3700 MHz). Unless appropriate measures are employed,
operation of unlicensed devices in the Extended-C band could directly
interfere with these earth stations, which are very sensitive to
interference. Nevertheless, because these earth stations generally are
located in remote locations, AT&T believes that mitigation measures,
such as geographic limitations, power limitations, frequency hopping,
and/or use of "smart" devices, can be implemented to permit deployment
of unlicensed devices in this spectrum, while still protecting these
earth stations from harmful interference.

AT&T also operates other C-band earth stations that could be adversely
affected by unlicensed devices in the Extended-C spectrum unless
mitigation measures are implemented. Although these earth stations are
not licensed to receive signals in the Extended-C spectrum band, they
are authorized to receive signals in the adjacent C-band (3.7 to 4.2
GHz). Moreover, their antennae actually receive and amplify signals in
both the Extended-C and C bands, although only the licensed C-band
signals are processed. If interfering uses are permitted in the adjacent
Extended-C band, the interference potentially could "overdrive" the
earth stations' low noise amplifiers into their nonlinear operating
range and degrade C-band signals, thereby disrupting communications
received at these earth stations -- and those of other C-band earth
station operators. AT&T nevertheless believes the interference caused by
unlicensed devices could be effectively mitigated through geographic
limitations, power limitations, frequency hopping, and/or use of "smart"
devices.

In short, AT&T supports the proposed opening of spectrum for use by
unlicensed devices, provided that means are established to prevent
harmful interference to AT&T's C-band satellite earth stations. AT&T
looks forward to reviewing interference mitigation measures proposed by
those seeking to use such spectrum.

Sincerely,

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> Carol Wilner