If your WiFi router range does not cover some of your rooms what do you do? You install a WiFi repeater or some of the more recent WiFi mesh networking solutions. What I did not know is that you can do something similar for cellular connectivity if you don’t quite get a reliable signal from your telco’s base station.
Specifically, I’ve just come across a 900 MHz GSM repeater & signal booster that claims to be able to extend the 2G, 3G, and 4G cellular signal in a 100 to 300 m2 area, and sold for $59 on Banggood.
Here are the specifications listed for the GSM repeater:
- Operating Frequency Band – GSM
- Uplink: 890-915Mhz
- Downlink: 935-960Mhz
- Gain: 70dbm
- Outdoor Directional Antenna Gain – 8dB
- Compatible with 2G / 3G / 4G cell phone signal
- Power Supply – 12V DC via 110-240V DC adapter
- Dimensions – 135 x 105 x 23 mm (Aluminum Alloy)
- Temperature Range – -10 to 60°C
900 MHz corresponds to the B8 LTE band, so it’s not only for 2G GSM as I first assumed. You’d better check out if your country supports 900 MHz for 2G, 3G and/or 4G, and may also want to double-check whether such signal booster does not break any local regulations. The kit comes with the repeater itself, an indoor antenna, a high-gain outdoor antenna, and a power supply.
The installation looks quite easy, and the hardest part is probably to attach the outdoor antenna on a wall or roof and make sure it points to the closest base station. One way to check your frequency and/or base station location is with Network Cell Info Lite Android app.
If you’d prefer supporting more frequencies or a different frequency you’ll find various GSM repeaters on Aliexpress or Amazon US at various prices and some are tri-band repeaters with 900, 1800, and 2100 frequencies selling for around $100. While I did not personally know about those, cellular repeaters have been around for several years, and people who purchased those look to be satisfied in general.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
It is illegal to use such a device in my country. You can pay dearly for broadcasting in a commercial frequency band.
Good point. I’ll add something about legality in the post.
Pretty sure this is ~illegal~ basically everywhere and you’re a lot more likely to get caught than some dodgy ISM band module because eventually someone is going to come to investigate what is messing with the cell towers in your area.
Here it’s legal, as long as it is approved by the network operator (read owner of the spectrum) and of course as long as it’s a properly validated unit.
We had such a system at work, but it was not the greatest experience adding bars on the display, but not helping with the quality of the connection much. Sometimes we even disconnected it for better connections…
>Here it’s legal, as long as it is approved by the network
>operator (read owner of the spectrum) and of course as
>long as it’s a properly validated unit.
I really meant a random unit like this off of banggood etc.
A proper unit with the right certifications seems to be at least $500 in the US.
In some countries it is illegal in to broadcast on certain frequenct ranges only if the dB transmitter is over a specific limit, and that limit can be different for each freqency range. That is why it is for example legal to use weak FM transmitters in cars without a permit but over certain strengths you need permit to broadcast as a radio station.
There are two alternatives to a GSM repeater. Some modern telephones have “WiFi Calling” functionality built in. The second solution is VoIP over WiFi. I have a bad experience with VoIP. Now we are testing “WiFi Calling”. This looks promising, but it doesn’t work on every phone.
Using your phone to talk over WiFi with WhatsApp etc is Voip too ?
WiFi Calling is great when you can get it to work, but the matrix of which providers support it on any given model of phone (and with which specific firmware) is a nightmare – made worse by their habit of only supporting it on certain contract types. Even more irritating is that some operators (eg Vodafone UK) support it for voice calls but not for SMS, which nixes use for bank etc. authorisation codes…
In Poland it’s illegal and can get you into serious trouble. It can improve network coverage for one house but destroy it for all neighborhood. It’s also bad in terms of security – neighbor becoming a man-in-the-middle.
I looked up UK, a small quote ” You should only buy repeaters from reputable retailers and look for a ‘CE’ mark on the equipment.
Indoor repeaters that claim to be 4G and/or LTE only (or 800 MHz only) are also unlikely to meet our requirements. Legal indoor repeaters must boost a 2G or 3G signal at all times. ”
Full detail here. https://www.ofcom.org.uk/about-ofcom/latest/features-and-news/mobile-phone-repeaters
I have used VZW for years and have always had a a poor signal at home; after enough inquiries they offered (“on loan indefinitely and free of charge”) a Samsung 4G LTE cellular repeater. It piggy backs off of my broadband connection and has its own GSM receiver etc. as I understand it the device is a femtocell and will act as its own tower. The unit retails for quite a lot, but the gain on the Samsung will adjust itself so as not to drown out neighboring cell sites etc. whereas the cheaper units aren’t always quite as “considerate”… Read more »
Yes – Femtocells are an alternative approach, and if your cellular provider supports them, a much better one. Femtocells are legal in the regions they are sold/provided in, and work with the cellular network provider’s infrastructure to create a new, very small and low range, cell using your domestic broadband internet connection to backhaul to your cellular provider. As a result they are designed to be compliant with local standards, power levels, and not cause interference. However they are not universally available (one UK provider has, I believe, stopped providing them now)
It is also illegal in France https://archives.arcep.fr/index.php?id=11946 (which makes sense : those equipments are using licensed frequency bands that only operators can use – and they are liable in case of bad uses e.g. if an equipment is leaking out-of-band emissions beyond what’s permitted. So operators won’t enable uncontrolled equipments (which can transmit within the bandwidth of all 4 operators in the band, possibly leaking emissions in neighbor channels or bands, also possibly having nasty effects due to bad deployments when some kind of larsen increases the leaking and blocks all other equipments around…)). Remember that cellular bands are also… Read more »
Do such signal boosters have any influence on human health? Any proven neurologic effects or some other deseases?
Yes, it tends to improve your health by keeping conspiracy seekers away 🙂
I used something similar in my old house where I had weak cell signal. These things don’t output more power but allow you to position the cell tower antenna high and point it at the cell tower. Then you place the local antenna in your attic pointing down towards the occupied part of your home. Went from marginal one bar to 3-4 bars. The one I used cost about $400 but worked on all US GSM cell bands.
I wouldn’t be surprised if just connecting the two antennas together (i.e. without the amplifier) already helped quite a bit, thanks to the directional antenna and can be placed outdoors. In this case there wouldn’t be anything illegal since it would just be a piece of electric wire helping to propagate the signal.
The insertion loses will be too high. The resulting signal will be lower without active amplification.
I am curious to see what kind of hardware is inside this box.
Probably something that acts as an amplifier.