[Federal Register Volume 59, Number 20 (Monday, January 31, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-2058]
[[Page Unknown]]
[Federal Register: January 31, 1994]
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FEDERAL COMMUNICATIONS COMMISSION
[DA 94-67]
January 25, 1994.
Request by WavePhore, Inc. for a Clarification of the Television
Rules to Allow Digital Data Transmission Within the Video Portion of
Television Station Transmissions
Comment Date: March 14, 1994.
Reply Date: March 29, 1994.
WavePhore, Inc. requests a clarification that television broadcast
licensees may, without prior Commission authorization, use WavePhore's
``TVT1'' system to transmit digital data signals within the visual
pass-band of television station transmissions. The system transmits
digital data within an NTSC television signal, between 3.9 MHz and 4.2
MHz within the standard 6 MHz channel, at an amplitude close to the
video noise floor. The request states that the ``TVT1'' system now
transmits data at a rate of 384 Kbps, and may soon be able to send data
at a rate of 1.544 Mbps. WavePhore, Inc. asserts that its system
generates no out-of-band spectral components.
According to the request, the system causes no visual degradation
of the television picture, as viewed on any commercial television set,
because: (1) all commercial television tuners filter out that part of
the spectrum that contains the data; (2) the amplitude of the data
transmission is only several IRE units above the video noise floor and
is therefore almost impossible to discern; (3) the data is injected
into a narrow 300 kHz band that adds no significant component to the
video noise when integrated and weighted over a 4 MHz bandwidth; and
(4) the data subcarrier's exact frequency and phase result in a
``picket fence'' data spectrum that is interleaved with respect to the
comb structure of the chroma and lumina spectrum.
Copies of the request, and comments when filed, may be inspected
and copied at the FCC Reference Center, Room 239, 1919 M Street, NW.,
Washington, DC 20554. Copies may also be purchased from the
Commission's copy contractor, ITS, Inc., Room 246, 1919 M Street, NW.,
Washington, DC (202) 857-3800.
Interested parties are invited to submit comments addressing the
assumptions, experimental data, and conclusions set forth in the
request. Commenters are also asked to address whether any combination
of intrachannel data transmission systems may cause undue interference
to television broadcast signals.
For further information, contact David O. Bennett at (202) 532-
6495.
Federal Communications Commission
William F. Caton,
Acting Secretary.
[FR Doc. 94-2058 Filed 1-28-94; 8:45 am]
BILLING CODE 6712-01-M