By Charles Miller
It may obvious that for a cell phone to be able to make a call, it requires a radio transmitter. That transmitter connects you to a nearby cell tower. When you look at the typical smartphone, it is not apparent that it probably has up to three radio transmitters.
In the radio spectrum, not all frequencies are created equal. Some are good because they are clearer of static and can transmit over longer distances. These frequencies are much in demand and are strictly licensed by national governments. Other radio frequencies are less desirable because they are not good for long distances. Some of these are “unlicensed,” meaning you do not have to get permission or pay to use them.
Your smartphone uses cellular band frequencies for voice calls. Your service provider paid millions for the license to use those frequencies because those radio frequencies are the good ones. For other purposes, your phone might use unlicensed Wi-Fi and Bluetooth radio frequencies.
Those unlicensed frequencies do not have the same range as the more-desirable licensed ones. Sometimes frustrated, tech support people refer to those unlicensed bands as “garbage” frequencies. That usually happens when a client says, “My cell phone works miles from the tower, so why can’t you make my Wi-Fi do the same?” I suppose the answer is that you are not paying millions for Wi-Fi, so you are stuck using less reliable but free radio frequencies.
This recently came up in a phone conversation I was having, or rather trying to have, with a client. The connection was very bad, and every few minutes, we were disconnected. I queried the client about what kind of phone she was using, and she answered she was using her cell phone. That meant she was using the best available radio frequency, yet we were continually disconnected.
Upon further investigation, I learned she was using Skype on her cell phone, meaning she was using the much less reliable Wi-Fi radio rather than cellular. Whenever she walked more than a few meters from her wireless access point, the Wi-Fi signal weakened, and we were disconnected. I asked her to get as close to the Wi-Fi base station as possible and stay there.
Still, we continued to disconnect because she was also using a Bluetooth headset. Though the cell phone had a good Wi-Fi signal, when she moved more than about two meters from the phone, she broke the Bluetooth connection to the headset.
While cell phone signals are good for several kilometers from the nearest tower, Wi-Fi is only a few meters. And Bluetooth devices should be kept closer than two meters for best results. Greater distances are possible, especially where there is less interference, but the best connection is always the closest.
Charles Miller is a freelance computer consultant with more than 20 years IT experience and a Texan with a lifetime love for Mexico. The opinions expressed are his own. He may be contacted through his website, SMAguru.com.
