ICAO 9718 VOL I PDF

INTRODUCTION

The radio frequency spectrum is a scarce natural resource with finite capacity limits and for which demand is constantly increasing. Predictions of future demand for spectrum indicate a continuing rate of increase for all users and radio services and facilities that utilize radio waves as the world economies progressively expand. The competition among all users for the spectrum available is hence expected to intensify in the years ahead. In this competitive situation, even a user holding a spectrum allocation will not have an automatic right to retain that radio frequency spectrum, as a decision by an International Telecommunication Union (ITU) conference may require that spectrum be removed from any radio service to meet a superior justified demand for other radio services. Aviation is only one of many such competitors, albeit with the significant benefit of a worldwide cooperative forum, namely the International Civil Aviation Organization (ICAO), to coordinate and support its case.

Aeronautical services are recognized internationally to be prime users of radio frequencies without which aircraft operations would not be capable of meeting the global demand for safe, efficient and cost-effective transport. The prominent safety-of-life element, present during all phases of an aircraft’s flight, is accorded special treatment internationally and is granted protection from harmful interference through agreed measures. Aeronautical spectrum use in the main frequency bands amounts to around 14 per cent of the total available and is divided into two main functions: air-ground communications and radionavigation. The future will also see the gradual introduction of satellite-based services in accordance with the communications, navigation and surveillance/air traffic management (CNS/ATM) policies agreed at the Tenth Air Navigation Conference (1991) and approved by the ICAO Council.

Radio frequency spectrum congestion imposes on all users the duty of spectrum-efficient operation. The process of channel splitting, as employed in some aeronautical communication and navigation frequency bands, is an example of technological development helping to achieve spectrum-efficient operation and meeting future requirements without requiring additional spectrum. Modern sophisticated systems employing complex modulations are another facet of efficient spectrum use when transmitting more information within the same bandwidth. Extending radio services and systems into higher frequency bands is yet another. These measures will continue for the foreseeable future.

The process of international competition between expanding radio services obliges all existing users (i.e. aeronautical and non-aeronautical) to continually defend and justify the retention of frequency bands or the addition of new bands to those already allocated to their service, subject to the same conditions as apply in other services, civil aviation operations are expanding globally, requiring more navigation and communication facilities and thus creating additional pressures on the already stressed and limited spectrum availability. The civil aviation community must accordingly develop and present, as necessary, its agreed policies and its quantified and qualified statements of requirement for radio frequency spectrum so as to ensure the continuing availability of adequate radio spectrum and, ultimately, the ongoing viability of air navigation services throughout the world.

This document contains a balanced and justified presentation of aviation needs, and it will be made available to all aviation interests involved in the frequency management process. It will be updated through regular amendments based on technological developments in communication, navigation and surveillance systems for aviation and changing operational requirements on the utilization of these systems. These updates also consider the decisions in the ITU, including amendments to the ITU Radio Regulations and the development of relevant ITU-R Recommendations and Reports.