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Werbach proposal: Ahead of its time?

A News.com reader writes that columnist Kevin Werbach's ideas are a little ahead of our current technological ability in 2001 and the near future.

 

  
Werbach proposal: Ahead of its time?

In response to the Nov. 29 column by Kevin Werbach, "Free the airwaves!":

The spectrum does seem to be hitting peaks of utilization with little strategy for moving forward. Increasing pressure is placed on existing spectrum services like government allocation. The current trend has been a push upward in the microwave segment, pushing new services higher.

One constant problem with this strategy is the inherent physical limitation in microwave radio propagation. Microwave propagation is limited to absolute line of site and therefore has very limited range. These frequencies also have other limitations. For instance, in regard to weather, 10GHz waves become attenuated when it rains because they are the same physical size of the 10GHz wave and therefore the signal is absorbed.

There are many services that share spectrum with one another and simply discover problems. Many times licensed services put out extreme amounts of radio emission to accomplish their goals. Sometimes this power output is necessary. Sharing services become overloaded by this RF output and cannot perform their functions.

For instance, when the Navy uses ship-to-airborne radar in the 400MHz block, they cause interference to UHF communications across the board. Sometimes the interference is extreme, rendering the frequency block nearly useless. It isn't a question of just voice communications; these frequencies are used for all sorts of applications that many times are totally incompatible.

In addition, spectrum partners do not share nicely. Services will simply put out more output when faced with interference from a sharing partner. Take paging companies, for instance. They are cited many times by the FCC for running too much power (beyond the legal limit) and running dirty transmitters, which cause interfering harmonics across multiple-band users.

Current digital technologies have their own problems. It takes so much spectrum to send large amounts of data that if everyone jumped on the wireless wagon we would saturate the frequency allocation unless we limited the bandwidth considerably. Look at how poorly most digital cell phones work in terms of voice quality and range. Cell companies want to keep squeezing the bandwidth, and the end customer is paying the price in quality.

Imagine how lousy all radio services would sound and operate if we took a "networked" approach to radio. The fundamental structure of packet technologies is best suited for trading information and files, not for high-quality voice products. There really isn't enough bandwidth to support good digital services even if they share. Our current technology is too limited.

Ultra-wideband is so new, I do not think it is fair to label resistance as "overheated." Tests are being run to determine the true interference qualities of wideband. I support the FCC and others for taking their time in evaluating its characteristics. One thing that is historically certain: Once the cat is let out of the bag, there is no stopping it when it comes to radio.

It seems Werbach's ideas are a little ahead of our current technological ability in 2001 and the near future.

Brian Levy
Valley Village, Calif.