Mobile phone repeaters: an invisible risk when individuals improvise as operators
The development of mobile communications has profoundly transformed our daily life and relies on a complex technical infrastructure consisting of interconnected antennas and base stations. In cases of insufficient reception inside certain buildings, private individuals sometimes consider — or proceed with — the installation of mobile phone repeaters, also referred to as GSM amplifiers or «repeater». While this solution may appear to be a simple way to improve signal quality, the installation and operation of such equipment by private individuals raise significant technical and legal concerns.
May I personally put a repeater into service and operate it?
No. The putting into service and operation of a repeater may only be carried out by a mobile network operator or by a company mandated by the mobile network operator.
If OFCOM identifies such a device, in particular within the context of an interference case, it will first be seized. As a rule, the device will subsequently be confiscated. Its user may not only face a fine, but will also be required to bear the costs associated with locating the interference.
Persons who already operate compliant equipment with a valid authorisation from the relevant mobile network operators may continue to use it, provided that the conditions set by those operators remain unchanged.
How can I improve my reception?
1. Ask your mobile phone provider about a repeater
If you have no or poor mobile phone reception, contact your mobile phone provider. They can advise you and, if possible, suggest a solution. Bear in mind that such solutions may incur costs for planning, installation, equipment or operation.
Contact details for providers:
- Salt: repeaters@salt.ch
- Sunrise: repeaters@sunrise.net
- Swisscom: Team.MDS@swisscom.com
If you do not know which network your mobile device uses, please contact your provider first to clarify this.
2. Use WiFi Calling
In many cases, mobile reception inside buildings can be improved without the use of a repeater by using WiFi Calling. This is a service provided by the mobile network operator that enables calls and SMS to be transmitted via a WiFi network.
Requirements for using WiFi Calling:
- internet access via a WiFi network or a fixed-line connection with a WiFi interface
- a mobile device that supports WiFi Calling
- an appropriate mobile subscription
To check whether WiFi Calling is available, the mobile network operator should be contacted directly.
Understanding what a repeater is
A repeater receives the signal from an existing cell, amplifies it, and then retransmits it within a given area in order to increase network coverage.
- Intended use
When installed by an operator or an approved service provider on behalf of the operator, it is calibrated to avoid interference and comply with emission standards.
- Non-compliant use
When an individual installs and operates a non-compliant or poorly adjusted device, the following risks may arise.
- Network interference
An incorrectly configured device can saturate the frequency, degrade call quality and even cut off service for neighbours.
- Network degradation
Unlike equipment installed and operated by operators, a private device may transmit at excessive power levels, exceeding legal thresholds.
- Feedback loops (oscillation)
If the outdoor antenna and the indoor antenna are too close to each other, the signal amplifies itself and causes radio interference that affects the entire surrounding network).