Monday, December 05, 2011

Spectrum utilization and a Buddhist perspective on space

The “Spectrum as Space” metaphor implies that spectrum is a neutral container that can be filled with radio signals, leading to naïve notions of utilization such as empty and full spectrum bands. “Spectrum” is imagined a collection of axes which mark out an abstract space, such as frequency, geography, and time (e.g. Robert Matheson’s “electrospace” concept, cf. Matheson & Morris 2011, The Technical Basis for Spectrum Rights: Policies to Enhance Market Efficiency).

However, that’s not the only way to look at it. Non-spatial models such “Wireless as Trademark” work just as well (see my 2008 paper De-Situating Spectrum: Rethinking Radio Policy Using Non-Spatial Metaphors): by analogy, a trademark stands for both a part of the wireless resource (customarily, frequency band x geographic region x time slot), and signals. The wireless resource is all possible radio operations. In such an approach, one is much less likely to ignore the importance of receivers in this approach than spectrum-as-space, where only transmitters can “fill the space” with signals. Any radio operation includes the use of a receiver, and that receiver-transmitter pair influences what transmissions are possible by third parties.

Curiously, I found a relevant perspective on this problem in a book on ethics – Stephen Batchelor’s Living with the Devil. He writes:
One tends to think of space in terms of physical extension and location. A body “occupies” or “fills” a space. For there to be “no more space” means that nothing more can be fitted into a room or a vehicle or a document. Outer space is that virtually infinite expanse speckled with galaxies and stars separated by inconceivable distances. “Inner space” suggests a formless expanse of mind in which thoughts, mental images, memories, and fantasies rise and pass away. Space seems to be the relatively permanent place where temporal events happen.  
Buddhist philosophers see space differently. They define it as the “absence of resistance.” The space in a room is under stood as the absence of anything that would prevent one moving around in it. To cross from one side of the room to the other is possible because nothing gets in your way. Rather than being the place where things happen, space is the absence of what prevents things from happening. The space in the room is nothing in itself; it is just the absence of chairs or tables, glass walls or hidden tripwires that would obstruct movement within it. In encountering no such resistance, we are able to move about freely. [In the footnotes, Batchelor ascribes this approach to the Geluk school of Tibetan Buddhism.] 

The customary view that Batchelor outlines is “space as a set of dimensions” that informs the Spectrum as Space metaphor. One can transpose his summary to spectrum as “the relatively permanent place where [radio operations] happen.” The “Buddhist” view, on the other hand, would see spectrum as the absence of factors that would obstruct radio operations. Existing radio operations, including receivers, would provide resistance to new operations, even in quite distant frequency bands. And there is an interaction between the agent that wants to move about and the nature of obstructions: neither a mouse nor a monkey would have no trouble scurrying around in a restaurant, while a person would be obstructed by all the tables and chairs. Likewise, one has to first define the new operation one has in mind before deciding that spectrum is “occupied”; calculating utilization is not a straightforward matter of marking spectrum as “empty” or “full.”


Shafeen Charania said...

Fascinating! Thanks as always Pierre for provoking possibilities.

Do you feel that the FCC might now regulate/license capacity + behavior -- somewhat akin to net neutrality, where capacity owners are able to control behavior within their space?

Or do you think that they might further subdivide the auctions into two separate acts - what are you licensed to do, and where are you licensed to do it? Do you think the licenses will be mutually exclusive? You can either own and resell capacity, or you can purchase and resell content/behavior/etc.?

This could be a way for licensors to expand their revenue potential without changing the size of the pie??

Pierre de Vries said...

Not sure I understand the question, Shafeen, so my apologies if I'm going off on a tangent.

The big change in wireless regulation in the last thirty years has been a shift away from operating conditions that specify the technology the operator (licensed or unlicensed) has to use. For example, compare the PCS and AWS cellular rules where you can use any technology (GSM, CDMA, etc.) with the requirement to implement a very specific technology stack as a TV licensee. So in that sense the FCC is much less specific about behavior (in engineering terms) than it used to be, and appropriately so.

The standard perspective is still very much in terms of "spectrum holders", where spectrum is a chunk of something, rather than the way I think of it: the FCC authorizes the transmission of certain energy levels over certain frequencies in certain places.

A spectrum chunk view lends itself to exclusive licensing, but is also common among people who think sharing is the future - they just think of carving up the chunks more finely.

I believe a dynamic, behavioral view will lead to more concurrent operations than today, which should increase total social welfare - including increasing revenue.