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Radio is the technology of communicating and signaling by radio online. Radio waves are electrical waves of high frequency from thirty to thirty thousand hertz and above. There are two basic types of radio technology - single-side and multi-side. The single-side radio consists of a single transmitter and a receiver; the multi-sided radio has two transmitters, usually on opposite sides of the room or building in which it operates, and a receiver.
Today, most people use either single-side or multi-side. Most commercial shortwave radio communications happen to be made using the single-side technology. In the single-sided system, each transmitter feeds a corresponding radio receiver into the speaker of the device. Because the radio transmitters are in close proximity to the listener, the sound quality is quite good.
On the other hand, for many people the shortwave radio communications are a good enough alternative. For one thing, they are much easier to install than the traditional Ham radio and they have a much wider bandwidth. With the Ham radio system you need a large dish and a lot of open space to receive the signals. On the other hand, the satellite communication can be set up almost anywhere. Unlike the ham radio system, however, this type of shortwave radio system allows only a limited number of satellites to receive the signals.
Shortwave radios have a fundamental difference from cell phones and microwaves in that the former can only pick up mobile radio waves (which are in the radio spectrum of frequencies below thirty megahertz). This range does not include the lower frequencies such as those used by baby strollers and low power home appliances. There is a possibility that some lower frequency mobile radio communications might be allowed through a base station antenna if they are part of a larger base station system. But, for now, the range is very limited.
The advantage of the satellite communications over the traditional radio broadcasting systems is that they do not use any antenna at all. It is transmitted via a communications satellite instead. It is this very same satellite that receives the radio signals. So, although there are antennaless systems that use the microwave wavelengths, these use antenna connections and so have limitations beyond those of the radio waves used by traditional radio broadcasting. The signals from the communications satellite are however strong enough to be picked up by a conventional base station antenna and used for transmission to a receiving antenna in the form of a radio signal.
So, from a purely technological standpoint, the two forms of radio communications are very different and the radio technology used on either type of radio depends entirely on the needs of the user. Cell phones use radio technology for making phone calls but because it is a low power use operation, it has been succeeded by lower power operation of the base stations. On the other hand, ham radio operators use a base station with an antenna to receive the signals for transmission to the local users and so use the more powerful wavelengths of radio technology. But for the user, whether it is a home user or a ham operator, neither type of radio technology is any different from each other in performance and so there is no reason why people should prefer one form of radio communication over the other. It is just that each type of radio technology does have a specific application in particular situations.
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