Mobile signal boosters: What’s legal?
Mobile signal boosters: Nextivity Cel-Fi RS2
The other device tested in the lab was the Nextivity Cel-Fi RS2 smart repeater. It comes in different versions, depending whether you’re on T-Mobile, Orange, O2 or EE, and costs £450.
The RS2 is an improvement over the RS1, supporting three times more 3G radio channels and a 28Mbits/sec HSPA+ version of 3G, while the RS1 could only manage 7.2Mbits/sec.
Physically, its two boxes look quite different from the older version, but the principle is the same – locate one unit at the place with the best mobile signal, usually near a window, and the other as far away as possible. The mobile signal is passed between the two boxes over a 5GHz RF link and repeated from the second box. The strength of the repeated signal is ingeniously modulated so the “window unit” can’t pick it up and cause a feedback loop.
It’s worked flawlessly during my testing, so there isn’t anything to report. It just sits there doing its thing and giving my phone a five-bar signal. When I tested the RS1, I found it would lock up occasionally and need a reset, but I’ve had no such problems with the RS2.
Unlike the Sure Signal, you can use a Cel-Fi RS2 in places with a bad or even nonexistent broadband connection. I can see my local BT exchange from the upstairs rooms of my house, but I routinely get faster connections over 3G than I do via ADSL2+, especially for uploads. That’s why I’m so pleased the latest RS2 version supports higher data rates.
The RS2 is available directly from some of the mobile networks, who usually stick their own name on it (for example, EE calls it the “Signal Booster”). That said, you might have trouble finding a salesperson who knows about it – one reader asked their account manager for a box to test, only to be told EE doesn’t provide signal boosters. After he pointed out the relevant page on EE’s website, the network soon admitted it does.
Whether you use a femtocell or a smart repeater, one thing you’re bound to notice is that your phone battery lasts longer. Anyone who does a lot of travelling will have spotted that their battery lasts far longer in a major city than out in the sticks. This is because your phone has to do more hunting when the signal is weak, and increase its transmitting power to reach more distant cell towers.
This is another reason why online arguments about phone battery life are redundant. One person might claim to get three days from a particular phone, while another might need to charge the same model every night. Both of them could have similar usage patterns, but simply live in areas with different mobile signal strengths. Both the Vodafone Sure Signal and the Nextivity Cel-Fi RS2 will give you a full, five-bar signal in your home or office, something your phone’s battery will really appreciate.