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Re: [Discuss-gnuradio] Cognitive Radio on agenda for FCC's meeting in Ma

From: Marcus Leech
Subject: Re: [Discuss-gnuradio] Cognitive Radio on agenda for FCC's meeting in March
Date: Thu, 24 Feb 2005 09:54:24 -0500
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While that sounds interesting (particularly as I'm a part-time radio astronomer), what you'll find is that most of the more sensitive facilities would rather not have
 transmitters of any kind anywhere near them--even their own.

At some facilities, the vehicular traffic within the facility is *all* diesel, to
 eliminate ignition noise--which is particularly bothersome for pulsar
 observations at 74 and 150mhz.

Given that cognitive radios will have a plenitude of tiny silicon microchip brains, they can (at least as a starting point), avoid the ITU-agreed radio astronomy frequencies, listed

Specific Protected radio astronomy frequencies:

-          13.36-13.41 MHz

-          25.55-25.67 MHz

-          38.0-38.25 MHz

-          73-74.6 MHz

-          406.1-410 MHz

-          1400-1427 MHz  [Hydrogen Line at 1420.406 MHz]

-          Radio Astronomy on a secondary basis 1610-1626.5 MHz

-          1660.5-1668.4 MHz [Hydroxyl Spectral Line 1665 and 1667 MHz]

-          Radio Astronomy on a secondary basis 1718.8-1722.2  MHz

-          2690-2700 MHz

-          4825-4865, 4950-4990 MHz

-          Formaldehyde Line 14,470-14,500 MHz

-          31.2-31.3, 36.43-36.5, 42.5-43.5, 48.94-49.04 GHz

-          97.88-98.08, 140.69-140.98, 142-149 GHz

-          262.24-262.76, 265-275 GHz

John Gilmore wrote:

This msg is about "Cognitive" radios, not just software-defined
radios.  Cognitive radios make major adjustments in their transmission
and reception behavior, based on observing the local radio environment.

Cornell makes some good points.  There are small areas of the spectrum
where NOBODY can transmit, so that passive receivers such as
radiotelescopes can receive.

I've been advocating for defining a simple scheme for "posting"
frequency bands with machine-readable signs (like the "No Hunting"
signs found on trees and fences).  It would have to be simple enough
that every cognitive radio transmitter could implement it, listening
to learn the rules of the neighborhood before transmitting.  The radio
astronomers could "fence off" their frequencies and physical locations
by occasionally transmitting these "No Trespassing" signs on a nearby
coordinating frequency.  Anyone interested?


Date: Tue, 22 Feb 2005 08:03:02 -0800
From: Seth David Schoen <address@hidden>
To: John Gilmore <address@hidden>

John Gilmore writes:
[Have we talked recently to folks at FCC about this?  Let's check in and
see what we can learn.  ...

This is presumably going to be a rule in ET Docket 03-108.

There's some continuing ex parte activity there.

Here's a reply comment critical of us and PK from the radio
astronomers at Cornell.


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