What are the specific technical requirements for a signal booster to be license-exempt in the UK

To be considered compliant and exempt from licensing, signal boosters must meet several key requirements outlined by Ofcom[1]. These requirements ensure that the device operates within the permissible radio frequency (RF) spectrum and does not cause harmful interference[3]. License-exempt mobile signal boosters must meet specific technical requirements, including power limits and frequency bands[3].

Key requirements include[5]:
* No Interference Signal boosters must avoid causing harmful interference or disrupting other users' connectivity by adapting seamlessly to changes in the network environment, minimizing the risk of interference.
* Network Safe Devices must be recognized and approved by mobile network operators, amplifying signals exclusively for the designated network without adverse effects on its operation or other users.
* Automatic Gain Control (AGC) Built-in AGC technology is imperative, preventing oscillation and maintaining optimal performance by adjusting gain based on the input signal's strength.
* Uplink and Downlink Shutdown The booster must automatically shut down or reduce gain in both uplink and downlink directions to prevent interference and ensure responsible usage.

License-exempt boosters are those that meet Ofcom’s stringent requirements and have been approved for use without a license[1]. As of May 2022, Ofcom has authorized the use of static indoor repeaters without a license, provided they meet specified technical requirements[8]. All mobile signal boosters should carry a CE mark, indicating that they comply with the relevant European Union directives and regulations, including the Radio Equipment Directive (RED)[3].

Ofcom maintains a list of approved mobile signal boosters that meet their regulatory requirements[3]. It’s essential to verify that the device is approved by Ofcom to ensure compliance with UK regulations before purchasing a signal booster[3]. Using an illegal signal booster can have serious consequences, as Ofcom actively enforces the signal boosting regulations surrounding these devices[1].