Signal boosters are a clever way to make sure you have the best chance of getting a good connection on a cell phone even when geography or atmospheric conditions mean only weak network signals are available. A dual-frequency band works on both the frequency bands on which cell phones operate in a particular world region.
Signal Booster Basics
A cell phone signal booster is similar in concept to a signal booster for a TV with an antenna. It receives a cell phone signal in the same way as the cell phone itself, then performs two functions: amplifies the signal to make it stronger, and then rebroadcasts it at a frequency that isn’t being used by any other broadcaster or receiver in the immediate area. This rebroadcast signal thus becomes the strongest one available in your area, meaning your cell phone should pick it up and maintain it with fewer or no dropouts.
Cellular vs. PCS
Most cell phone networks and cell phones operate on frequencies within one of two bands, similar to the way AM and FM radio works in different frequency ranges. In the United States, the two cell phone ranges are 824 to 894 MHz and 1850 to 1990 MHz, known for simplicity as the 850 MHz and 1900 MHz bands. They are sometimes also known as “cellular” and “PCS,” respectively, terms that date back to early analog cell phone networks.
A signal booster that can work on dual-frequency bands has more options for finding a specific frequency that isn’t being used in your location. That in turn makes it more likely it can produce a rebroadcast signal that is strong enough to be picked up and held by your phone. Using dual frequencies may be of particular benefit if you are in a moving car, where the effects of other local signals may change quickly, and your signal booster can quickly switch to a different frequency.
Different parts of the world use different ranges of frequency for cell phone communications. For example, while North America uses the bands around 850 MHz and 1900 MHz, Europe, Africa and Asia use the bands around 900 MHz and 1800 MHz. Some cell phones are marked as being “multi-band” or “dual/tri/quad band,” which refers to their ability to work with multiple sets of frequencies and thus work in multiple regions of the world. This is not the same as a multi-frequency signal booster, which is designed to work in one region only. If you do need a signal booster that will work away from your home country, make sure to check the specific frequencies with which it works.