Appendix D  -  Guidelines To Ensure Co-Existence Between Land Mobile, non-3GPP Land Mobile, NB-IoT, and LPWAN

This section is based on ECC/DEC/(19)02.

The technical requirements set out in sections 3 and 5 alone may not guarantee interference-free adjacent spectrum use in all cases.

The impact of LTE-based systems in the 400 MHz frequency ranges on narrowband PMR, DTT above 470 MHz, on radars, on the radio astronomy, on the fixed service, on PMR links in audio-visual production, on paging and SRD systems is described in ECC Report 28351. In this Report, the interference probability calculations have been performed for downlink capacity/traffic limited systems; results may differ for uplink capacity/traffic limited systems, which may tolerate a noise rise in UE receivers up to a level of the DL/UL imbalance.

One interference effect to be considered is the potential impact of Intermodulation Distortion in PMR receivers caused by neighbouring broadband signals. This is dependent on frequency offset of the LTE carrier from the victim PMR receiver, the received power, and the intermodulation performance of the victim PMR receiver at that frequency offset. No conclusion on the intermodulation effect from broadband interferers into narrow band victims could be reached in ECC Report 283 and additional investigations will be conducted within ECC.

ECC Report 283 considers that compatibility between LTE systems in the 410-430 MHz band and the Radio astronomy service below 410 MHz is possible provided that minimum frequency separation and separation distances are implemented.

LPWAN:

ECC Report 28352 considered a guard-band of 200 kHz between the TETRA base station (BS) and the LPWAN end device. This guard band is needed to minimise the interference from TETRA BS transmitter to LPWAN end device receiver.

ECC Report 283 considered the compatibility between a LPWAN system and airborne radars in the 410-430 MHz range is possible with a minimum guard band of 0.5 MHz from operating frequency edges.

ECC Report 283 considers the compatibility between LPWAN system in the band 410-430 MHz and the radio astronomy service below 410 MHz is possible under the condition of minimum frequency separation and separation distances are implemented.

LPWAN gateways (base stations) can operate with duty cycle limitations, if needed for compatibility reasons with adjacent services.

ECC Report 283 identified, based on measurements that compatibility with adjacent LTE is ensured with an improvement of the LPWAN receiver adjacent channel selectivity by 30 dB.

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