CEL-FI Products Comply With Ofcom’s UK Interface Requirement (IR21O2) Specification

7th Aug 2022

We revisit Ofcom’s UK Interface requirement 2102 (IR2102) to be reminded of the types of mobile signal boosters that fall under the remit of this specification and explain how CEL-FI products fully meet the regulatory requirements.

On 12 April 2018, Ofcom passed the Wireless Telegraphy (Mobile Repeater) (Exemption) Regulations 2018 which permits the use of certain types of mobile phone boosters without the need for a licence. Two categories of repeaters are covered by the licence-exempt regulation: static mobile phone repeaters for indoor use, and low-gain mobile phone repeaters for in-vehicle use. These repeaters must comply with the required technical standards and conditions of use.

But What Exactly Is A Mobile Signal Booster?

Mobile phone boosters or repeaters amplify signal between a mobile phone and a mobile network tower. It can improve coverage inside homes, offices, and other buildings, where mobile signal is weak.

It consists of three units: a reception antenna, a signal booster, and an internal rebroadcast antenna. Think of the latter as a mobile phone mast designed and configured to provide mobile signal inside a specific building only. The external antenna will collect the best mobile signal from outside and transmit it to a mobile signal booster unit which strengthens the signal and retransmits it internally.

What Is A Static Indoor Repeater?

Static indoor mobile signal repeaters can boost indoor signal where there is reasonable mobile coverage just outside the building, but indoor coverage is poor. These repeaters are for indoor use only – it must be used inside a building which has a ceiling or a roof.

The ‘downlink’ from these repeaters (the part that connects the repeater to the mobile phone) must not be used outside or in semi-open locations. The ‘uplink’ (the part that connects the repeaters to the mobile phone network) can be used either indoors or outdoors.

How Do I Know If My Mobile Signal Booster Falls Within The Ofcom Regulations?

Ofcom has a document outlining the interface requirements of mobile repeaters. Here is a basic checklist to see if your mobile signal booster complies with the licence-exemption regulation.

Does your repeater boost more than one network at a time?

Ofcom stipulates that mobile signal boosters are only permitted to boost a single operator at a time. However, you are allowed to switch the booster to a different network.

Does your repeater boost mobile signal with more than 100db?

The uplink and downlink system gain of a repeater may not exceed 100 dB. If the repeater is no longer serving an active device connection it must, after no more than 5 minutes, the uplink noise power must reduce to no more than −70 dBm/MHz EIRP.

Does the booster interfere with the mobile networks?

To protect mobile networks, any boosters that cause undue interference or other adverse impacts on the technical quality of service of mobile operators’ networks, other mobile users, and other users of the radio spectrum, are deemed unlawful. The boosters must select only licence-exempt bands and frequencies for the network they are boosting and self-configure to ensure that they do not cause any harm to the network, according to the rules specified in IR 2102.

On which frequency band(s) does your repeater broadcast?

There are only some frequency bands that fall under the licence-exemption regulation. If your mobile repeater amplifies any other bands, it is unlawful. The frequency bands that can be repeated with an indoor static mobile booster are:

800	791-721 MHz (Downlink)832-862 MHz (Uplink)
900	880-915 MHz (Uplink)925-960 MHz (Downlink)
1800	1710-1785 MHz (Uplink)1805-1880 MHz (Downlink)
2100	1920-1980 MHz (Uplink)2110-2170 MHz (Downlink)

What Happens If I Install A Mobile Booster That Does Not Comply?

According to Ofcom: “Repeater devices transmit or re-transmit in the cellular frequency bands. Only the mobile network operators are licensed to use equipment that transmits in these bands. Installation or use of repeater devices by anyone without a licence is a criminal offence under Section 8 of the WT Act 2006. Any person found guilty of installing or using such devices without a licence would be liable on conviction to a fine of up to £5000 and/or up to 51 weeks’ imprisonment (Six months in Scotland and Northern Ireland).”

Frequency has been called to many premises where unlawful boosters disrupted the effectiveness of the Network’s performance and Ofcom inspectors demanded the booster to be removed.

What About CEL-FI?

CEL-FI products are the ONLY mobile signal boosters available on the market that are licence-exempt and fully comply with the regulatory requirements with Ofcom IR 2102 (UK) and ComReg S.I.No.283 of 2018 (Ireland).

The CEL-FI promise is to protect the operator’s network, deliver the best in-building mobile performance, and be the easiest solution to install.