Wireless spectrum, although invisible to the naked eyes, is a huge asset to any country. Spectrum regulators all over the world contributed huge income to the nation through spectrum auctions. For example, Germany raised over EUR 50 billion through their 3G auctions back in 2000. The auctioned spectrum typically last for a certain period stipulated by the respective regulator, e.g., 20 years, after which the regulator has the right to retrieve the spectrum for other purposes. To put in perspective, EUR 50 billion over 20 years is equivalent to a whopping EUR 6.85 million per day!
Side note: 3G licenses for most countries will expire in early 2020’s.
On the other hand, regulators also allocate unlicensed spectrum to serve different needs, e.g., cordless phone in your home or Wi-Fi in your office. These wireless systems need to be setup quickly and easily by end users and are best to avoid lengthy licensing process. In other words, the end users do not need to get a spectrum license to own the networks operating in unlicensed spectrum for their own use.
The decision to make certain spectrum licensed or unlicensed is often complex and involves cost-benefit analysis in a bigger picture for the benefits of the people. While collecting huge revenue allows the government to implement initiatives to help the needy, empowering the people with access to technologies increases their productivity and thus incomes. In some cases, the government should catch the fish and feed the people; in other cases, the government should teach the people how to fish.
Due to increasing demands for spectrum, regulators find it harder and harder to fulfill spectrum needs – some called it SPECTRUM CRUNCH! However, when we look at the situation closer, we realized that although spectrum is allocated, the utilization is low. For example, measurements conducted in US found that spectrum occupancy is on average <10%. Independent measurements done in Singapore showed similar results. These alarming results called for a need to review the way spectrum is being utilized.
Instead of static allocation and utilization, “dynamic sharing” might be the answer. Imagine other sharing economies such as Uber and Airbnb where resources are shared dynamically; the same concept is applicable for spectrum.
TV White Space (TVWS) is one of the first wireless communication systems to experiment with dynamic sharing of spectrum. In TVWS, the network queries an online geo-location database (GLDB) to determine what spectrum resources are available for sharing. The GLDB acts like the Airbnb website where demands are matched with supplies, with slight difference which I will discuss in my next article.
Due to the need to query the GLDB prior to start of communications, the regulator has the flexibility to “change rules” on the fly, e.g., changing the amount of spectrum available for sharing, or the timing of such sharing. The pre-requisite for this to happen is the wireless system using the spectrum on a sharing-basis must have intelligence built-in to react to changes.
Extending GLDB to other frequency bands and wireless systems will have the opportunity to increase spectrum utilization. A more genetic form of GLDB called Spectrum-Access System (SAS) will be the tools to enable future “Digital Regulator”.
In Digital Regulator era, access to spectrum will be done dynamically. Certain spectrum will remain license-exempt whereas certain spectrum will still require a license to operate. Instead of fixed allocation of spectrum, unlicensed users use the spectrum in the bands allocated as unlicensed by the regulator; and in the case of operators using licensed spectrum, the spectrum may be obtained via real-time auctions. The enabler behind this is likely to be an Artificial Intelligent (AI) engine running in the background.
Achieving full digital is very challenging if not impossible. A more likely scenario in the future will be a mixed of pre-allocation and dynamic allocation. For instance, the regulator may allocate N number of frequency channels to each operator while keeping M number of licensed frequency channels as common pool for access dynamically, thus increases the overall spectrum utilization and reduces the cost to the end customers.
The Digital Regulator era will come and regulations could move at the speed of Moore’s Law. It is a matter of timing. Before that, regulators and the stakeholders have to sort out various challenges such as deterministic of connection costs (or is it required in the future?), enforcement in case of misuse, security threats and many other potential new issues that will surface. Meanwhile, let’s start thinking about this and be prepared for the new and exciting things to come in the future!