Ofcom: Coexistance issues for 2300 and 3400 MHz bands

AMSAT-UK Logo

AMSAT-UK Logo

The proposal to sell-off spectrum at 2.3 and 3.4 GHz will impact both the Amateur and Amateur-Satellite Services.

The UK communications regulator Ofcom has published a consultation setting out proposals for addressing technical issues related to the forthcoming award of 190 MHz of spectrum at 2350-2390 MHz, 3410-3480 MHz and 3500-3580 MHz. It is expected that these frequencies will be used for 4G mobile services using Long-Term Evolution (LTE). Ofcom say In certain circumstances, LTE has the potential to cause interference to applications/devices using spectrum in adjacent frequency bands.

Ofcom has assessed the impact for both licensed and licence-exempt uses of the release and adjacent spectrum.

The Amateur Service is covered in section 9 page 73 and the Amateur-Satellite Service in section 12 page 87 (12.25-12.30) of the consultation document.

With regard to the Amateur-Satellite Service Ofcom refer to the ITU-R frequency filing database as a source of information. National administrations rather than individuals are responsible for submitting this information and it is suspected that not all administrations have been doing so which may lead to usage being understated.

Regarding the impact on 2400 MHz Ofcom say:

12.29 In our consultation on amateur usage we acknowledged that the 2400-2450 MHz band could experience an increase in background noise as a result of the release and set out advice for amateurs planning continued use of these bands.

12.30 We consider that there is no need for further detailed analysis of the impact of the release on the amateur satellite service as there is a 10 MHz separation between this use and release band and there should be no issue greater than the in-band ISM interference.

It is presumed that in 12.30 Ofcom are saying they expect the interference to 2400 MHz from the LTE release band will not exceed that of a WiFi router operating on the desired frequency. The weak signal segment 2400-2402 MHz is not used WiFi but will clearly suffer interference from the new LTE band.

Consultation document
http://stakeholders.ofcom.org.uk/binaries/consultations/pssr-2014/summary/pssr.pdf

The consultation closes on May 15 2014, you can respond online via the consultation page at
http://stakeholders.ofcom.org.uk/consultations/pssr-2014/

Read the joint response to the Aug 9, 2013 Ofcom: Spectrum Sharing Consultation
https://amsat-uk.org/2014/01/12/ofcom-spectrum-sharing-consultation/