ITU-R REPORT M.2170 PDF

Introduction

WRC-07 approved WRC-12 Agenda item 1.21, "to consider a primary allocation to the radiolocation service in the band 15.4-15.7 GHz, taking into account the results of ITU-R studies, in accordance with Resolution 614 (WRC-07)", in order to provide adequate spectrum for new advanced radar systems to function. Emerging requirements for increased image resolution and increased range accuracy necessitate wider emission bandwidths than are currently available. Allocating a primary radiolocation service in the 15.4-15.7 GHz band will provide additional spectrum for new advanced radar systems with increased image resolution and increased range accuracy that necessitate wider emission bandwidths than are currently available. Operation of radiolocation radars in this band will not adversely affect other co-primary services and should operate compatibly with the radio astronomy service in the adjacent 15.35-15.40 GHz band.

The 15.4-15.7 GHz band is allocated on a primary basis to the aeronautical radionavigation service (ARNS). There are no ICAO-standard ARNS systems that currently operate in this band although ICAO standards exist for aircraft weather radar systems. While the ARNS is recognized as a safety service as delineated in No. 4.10 of the Radio Regulations (RR), radiolocation services have demonstrated compatible operations with radionavigation radars in other bands over many years through the use of similar system characteristics such as low-duty cycle emissions and scanning beams as well as other interference reduction techniques. Studies within the ITU-R addressing compatibility between the radiolocation and radionavigation radars in other frequency bands provide reasonable evidence that sharing in the band 15.4-15.7 GHz between these services may be feasible. Recommendation ITU-R M.1730-1 contains the technical characteristics and protection criteria for radiolocation radars in the band 15.4-17.3 GHz and Recommendation ITU-R M.1372-1 identifies interference reduction techniques which enhance compatibility among radar systems.

Also, Report ITU-R M.2076 (2006) contains further mitigation factors for radiolocation interference to radionavigation radars in the 9 GHz band, many of which may apply to the band 15.4-15.7 GHz as well. There is also limited use of the band in some countries for non-ICAO aircraft landing systems. A portion of the band is also allocated to the FSS limited to feeder links for non-GSO MSS and in both space-Earth and Earth-space directions, though there are no systems that operate in the band. The necessary compatibility studies per WRC-12 Agenda item 1.21, Resolution 614 (WRC-07) are included in this Report.