Incentives Urged To Encourage Efficient Spectrum Use

The Commission already offers incentives -- for example, in the 900 MHz ISM band, where it has 2 power limits depending on how a radio operates, Bose said: “If you hop over a certain rate, you cause less interference to others, so [the regulators] incentivize people by giving them a higher power limit when they do that. This is a great example of incentives working well.”

“Incentives really come back to the profit motive,” said U. of Colo. Adjunct Prof. and former OET Chief Dale Hatfield. Carriers that operate systems more efficiently can lease unused portions or put more traffic through their infrastructure, “getting economies of scale that comes back to profits,” he said.

In enforcement, the FCC should look at the network’s performance, Hatfield said: “You can’t just look at efficiency at the physical layer. You have to look at the network’s efficiency at different layers of the protocol stack, and maybe things like riding traffic around congested areas. Why should we reward good bits per second per hertz performance and not the performance that rides the traffic around that entirely?”

Regarding predeployment conformance of spectrum- efficient systems, Hatfield said the FCC, through its cognitive radio proceeding, “is getting a very relevant experience.” But he said the Commission errs by focusing mostly on the device level and not the system level. “Testing to prove conformance is much more complex and more intrusive because you have to look deep into a person’s design to see whether the system is efficient,” Hatfield said: “That’s quite challenging but there has been progress in the cognitive radio proceeding.”

Rewarding good behavior is challenging but could work, Hatfield said. “If we are going to reward good behavior, we've got to define what a good behavior is and then we have to design an award structure around that behavior to provide the incentives,” he said. The design of the reward structure presents challenges as well, he said, including “property incorporating geographic variability, accommodating dynamic versus static behaviors, and providing incentives for inter-system cooperative behavior.” Hatfield said there’s a “difference between preventing bad behavior and rewarding good behavior in terms of the intrusiveness and the details a regulator has to look at in the network.”

Hatfield said a clear definition of enforceable property rights will enable the marketplace-oriented system to work properly. He also said “a clear and enforceable definition of spectrum efficiency is crucial for the tiered approach to work successfully. Our ability to come with such a definition is hardly assured.”

The best way to ensure efficient spectrum use is “broadening the static allocation,” Bose said: “When any new band comes out, we should think about having some incentives in place like in the 900 band and think what we can do to leverage existing infrastructure to enable a control function on these devices us we get toward a fully ad hoc regime.”

A critical issue is how the Commission defines harmful interference, according to several speakers. “A very hard problem to resolve is how to make a language universal across” the FCC, said Stevens Institute of Technology’s Paul Kolodzy: “I don’t think the FCC got far in that area.” Using the same numbers and the same terminology across different bureaus would help, Kolodzy said: “FCC will eventually get there but they haven’t yet.”

Spectrum for 4G wireless service could be allocated as early as 2007 if the world’s administrations reach agreement at the next World Radiocommunications Conference (WRC), Motorola Labs’ Joseph Nowack said at a session on 4G. The administrations of China, Korea and Japan, which are leading the effort, have agreed tentatively to look at allocating spectrum between 3.3 and 4.6 GHz for 4G, he said: “I don’t see a tight cooperation on the research level but on the minister level, that’s what they are looking at.” Much 4G testing is going on worldwide and “the idea is to get [speed] greater than 100 megabits per second, up to 1 gigabit per second,” Nowack said. For example, he said, Motorola is doing 4G experiments in N. America, and Europe has a govt.-funded research program designing an air interface to define a 4G cellular system. “The largest effort in the work is in China where 300 or more people are looking at what’s called the Future Project,” expected to demonstrate its results this year or next, Nowack said.