Wireless operators around the world are foolishly sitting atop a $130 billion stockpile of TDD spectrum assets rather than using those frequencies to solve the looming spectrum shortage, according to Belgian TD-LTE small cell vendor Accelleran.

TDD spectrum, unlike the more commonly used FDD spectrum that provides the foundation for legacy cellular networks worldwide, is composed of unpaired frequency bands. When European operators paid more than $160 billion to buy 2.1 GHz FDD spectrum for WCDMA more than a decade ago, they also got nearby chunks of TDD spectrum, which Accelleran estimated is proportionally worth $25 billion.

Accelleran contends there is an even larger opportunity cost than that stemming from Europe's unused TDD spectrum.

"This colossal waste is significant enough just in its purchase price, but the missed opportunities to the operator and the wider economy are even larger," contributing to the total $130 billion cost estimate, Accelleran said. "What is more, at a time when LTE roaming is a challenge many of these bands are usable globally, representing another waste," it added.

TDD has long been the ugly stepsister of the preferred paired FDD spectrum, but that is changing with the rollout of TD-LTE worldwide.

The Global mobile Suppliers Association (GSA) announced this week that 30 TD-LTE systems have been commercially launched in 21 countries, including a second network in China earlier this month. Some 11 percent of live LTE networks incorporate the TDD mode. So far, 17 operators have launched LTE service using only the TDD mode, while 13 operators have deployed both FDD and TDD modes in their networks.

Accelleran supports Europe's proposed harmonization of 3400-3600 MHz spectrum towards a "TDD preferred" allocation and 3600-3800 MHz spectrum towards a TDD allocation. The company's extrapolated economic value of this spectrum in Europe for a decade between 2005 and 2015 exceeds a price tag of $2.5 trillion.

"In some cases this spectrum is in use, but mainly for fixed wireless applications, which at the best case yields a fraction of the economic value mobile services would generate," it added.

Japan is preparing to allocate 3.5 GHz spectrum next year, while the United States is moving forward to set up a spectrum-sharing scheme via with the band, which could be used for small cells, among other uses. Europe is developing similar proposals for shared access, but for the 2300-2400 MHz spectrum, Accelleran said.

For more:

- see this Accelleran release

- see this GSA release

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