Oh dear. This is a rats nest of international agreements, policies, directorates, and a further plethora of words that nobody wants to hear.
The whole world, and I do mean world, of telecommunications is watched over by the International Telecommunications Union, ITU. This comprises representatives from:
193 Member States,
579 Sector Members
175 Associates
And 52 Academia
The responsibility of all these representatives is to represent, globally, the interests of all spectrum users and to maintain harmonisation and standardisation across the three regions the globe is divided into.
More info here:
In the image below you can see that the World has been split into three separate regions. We are in Region 1 which is colloquially referred to as CE even though it covers the African continent and the FSU and Baltic States. Region 2 is referred to the FCC region, even though the FCC has nothing to do with regulation outside the CONUS. Region 3 covers the Middle and Far East as well as Australia and New Zealand. This is made up of areas that use both the CE and the SRRC (State Radio Regulation of China) standards.
Each of these three regions have there own standardisation requirements and regulations. As drone users the two primary interests are the frequencies used and the power levels permitted, and these can vary quite considerably between regions. As an example my amateur radio license permits me to use up to 400Watts to the antenna on 2.4GHz and 5GHz, BUT, I cannot use my amateur radio privileges from any aircraft, including model aircraft and balloons. Where as in the USA they can transmit non-spread spectrum up to 1500watts from airborne platforms. Similarly our license exempt ISM allocations only permit 25milliwatts on 5GHz, where as in the USA they are permitted up to 1watt.
But WHY?
Way back before the digital age each region had its own telecommunication standards. These standards dictated such things like how many lines were needed to create a single frame of a TV image, how many 4KHz telephone channels were in a group and how many groups were in a supergroup. Even the channel spacing for broadcast stations on the MW allocation (EU = 9KHz, USA = 10KHz). Go back a little further and the dictator of these standards was formulated from the frequency of the AC mains supply. As time progressed the role of the ITU took on more responsibilities to where we are today. So as each Region has its own spectrum band plan it is the role of the ITU to ensure that all existing, and future, technologies can coexist on what is a limited resource, without undue interference to commercial, military, and government interests. The amateur radio allocations used to have these same protections but now they are only afforded the same protections as those of the license exempt ISM provisions we use for our drones, i.e Absolutely None At All.
