Paul Baran and open spectrum

Paul Baran, an engineer who helped create the technical underpinnings for the Arpanet (the precursor to today’s Internet), died Saturday in Palo Alto, California.  While everyone else celebrates his early contributions to packet networking, I will remember him for his open spectrum advocacy.

I never had the privilege of hearing Paul Baran speak live, but as I became interested in wireless spectrum, one of the earliest references I encountered was this transcript of Paul Baran's Keynote Address at the 8th Annual Conference on Next Generation Networks Washington, DC, November 9, 1994.

His title says it all:

Visions of the 21st Century Communications: Is the Shortage of Radio Spectrum for Broadband Networks of the Future a Self Made Problem?

And here's an excerpt:

   The key point at issue that we will question is the widespread belief
   that we don't have enough radio spectrum to go around. This is a
   common, fundamental belief. Since we live in a world of scarcity or
   natural resources it is almost automatic that we believe that there is
   a shortage of frequencies. This particular resource is somewhat
   different.
   
   This morning, let's start by reviewing this presumption of a permanent
   shortage. Let's consider how, with an application of already known
   technology, we could create even a surplus of frequencies. What may be
   going on is an inadvertent shortage created by a regulatory structure
   which has yet to appreciate the potential capabilities of the new
   digital signal processing technology as applied to communications.

Paul Baran is hardly the originator of open spectrum ideas, but the complete transcript shows he once again led the industry.

 

Comments

[Michael Elling]

Brough,

As a wireless analyst speaking about capacity issues and as an investment banker raising money for a femto-cell company I used to explain that all wireless gets reused, with wifi, based on a 300 ft radius, being almost infinite reuse.

All spectrum is essentially shared.

Michael

[brough]

Michael, the license-exempt spectrum that Wi-Fi uses certainly gets reused, spatially, and in many other ways, e.g. it's also shared with Bluetooth, Zigbee, microwave ovens, etc. Most important, the use of advanced modulations, directional antennas, MIMO, beam steering and so forth means the amount of sharing that is possible is increasing every year. Typically we see these technology advances deployed in the license-exempt bands first, as that's where anyone can do (almost) anything. So that's the spectrum where we see the most innovation.

Unfortunately, the license exempt bands represent a small fraction of the available spectrum. Most spectrum is reserved for specific licensees and dedicated for use with legacy (i.e. inefficient) technologies. What's worse, most spectrum is not even utilized most of the time in most places, including even downtown urban areas. See slides 17, 18, 19 here:
http://www.slideshare.net/Brough/open-spectrum-physics-engineering-commerce-and-politics-1465804

Thanks, Brough

[Camarad]

Thanks for the information! As a wireless analyst speaking about capacity issues and as an investment banker raising money for a femto-cell company I used to explain that all wireless gets reused, with wifi, based on a 300 ft radius, being almost infinite reuse.