3.5GHz band in New Spotlight
The 3.5GHz band is emerging as a new alternative to solve a mobile communications frequency drought. The 3.5GHz band has low quality compared to the current frequency. But the band is drawing attention as LTE technology is advanced and a frequency shortage deteriorated.
According to relevant industries on August 25, major countries including Korea, the US and China began to use the 3.5GHz band for LTE mobile communications with two or three years.
A frequency features strong linearity as its band becomes lower, it stretches further and strong diffraction, a property that circumvents obstacles. Accordingly, frequencies in the band between 700MHz and 2.6GHz were used as those for the LTE service. But an increase in the use of mobile phones and a sharp rise in mobile data use have led to a shortage of mobile telecommunication frequencies around the world.
Therefore, the 3.5GHz band is being developed as a new telecommunication frequency in earnest. Even though the band was evaluated to have too poor quality to be used for mobile telecommunication, the evolution of network technology prompted governments of nations around the world to begin to look for ways to utilize the band.
The Federal Communications Commission (FCC) opened a width of 150MHz (3550MHz to 3700MHz) which had been used for military purposes only for commercial use. The FCC received attention from governments around the world and the telecommunication service industry by suggesting a whole new frequency utilization plan while passing the Citizens Broadband Radio Service (CBRS) Plan. The CBRS Plan calls for the free and unrestricted use of some part of the 150MHz width in the 3.5MHz band. In addition, the US government can auction off some frequencies to business operators. It is the first time for a government to make the use of some of wireless telecommunication frequencies free, while offering them.
As the US government opened some wireless frequencies free of charge, leading ICT companies of America responded quickly to the measure. Alphabet which is the parent company of Google, Intel, Nokia, Qualcomm, Ruckus Wireless and Federate Wireless formed the “CBRS Alliance” and began to develop new LTE services based on free frequencies in the 3.5GHz band. Although a service plan was not yet announced by them, it is expected that a totally new form of a telecommunication service will be launched jointly by the six firms.
South Korea is also in haste to utilize frequencies in the 3.5GHz band for mobile telecommunications. The Frequency Deliberation Commission of the Office for Government Policy Coordination is planning to collect all frequencies in the 300MHz width in the 3.5GHz band (3400MHz - 370MHz) being used for repeaters by network broadcasting companies and satellite operators such as KT Sat, and reallocate them for mobile telecommunication services by 2017.
Experts are picking out frequencies in the 3.5GHz band as frequencies of the best quality that will play important roles among frequencies remaining in the 5G era.
China already set the 3.5GHz band as standard frequencies for 5G and is pushing forward with its international standardization.