RALI FX3 Microwave Fixed Services Frequency Coordination Glenn Odlum Senior Engineer Spectrum Engineering Section

FX3 - Key Points Point-to-Point and Point-to-Multipoint Fixed Links in GHz Line-of-Sight systems only Analogue and Digital Systems Technical Policy - Planning Rules Frequency Coordination Procedures Not a Link Planning Tool

RALI FX3 INPUTS -Spectrum Plan -ITU Radio Regulations -ITU-R Recommendations -Sharing Requirements -Spectrum Planning Reports -Industry Consultation OUTPUTS -Channel Plans -Planning Rules -Coordination Rules

Input - Spectrum Plan The Australian Radiofrequency Spectrum Plan identifies which radiocommunications services may operate in which frequency band Can’t issue a licence contrary to the Spectrum Plan Spectrum Plan may identify a frequency band for fixed service use but FX3 may not have an entry for it

Input - ITU Radio Regulations Sets many aspects of fixed services Article S5 - Frequency allocations by region Article S15 - Interference Article S21 - maximum eirp of fixed service transmitter in direction of a GSO satellite

Input - ITU-R Recommendations F- series (Fixed Service) –Radiofrequency channel arrangements –Error performance and availability objectives –Protection criteria (protection from other services) –Characteristics of fixed services to facilitate sharing with other services –Many others

Input - ITU-R Recommendations Other Series –IS series - Inter-service sharing and compatibility –P series - Radiowave propagation –SF series - frequency sharing between the fixed-satellite service and fixed service –SM series - Spectrum management

Input - Sharing Requirements In some bands fixed services are required to share spectrum with other services such as the mobile service, space service, fixed satellite service, or mobile satellite service. Sharing may impose restrictions on the fixed service and/or other services Increasing demand for fixed service to share with other services

Input - Industry Consultation Vital part of policy development Objective is reach agreement on how to make best use of a band Total agreement not always possible ACMA has a very good working relationship with most sectors of the industry

Output - Channel Plan Usually based on ITU-R recommendations Takes account of what type of use is supported (wide-band analogue, FM-FDM, low, medium or high capacity digital) Main and interleaf pattern Centre frequency and channel width Transmit / receive duplex spacing

Output - Channel Plan

Output - Planning Rules Expresses many policy requirements Consists of Assignment Instructions and Assignment Restrictions on a per band basis and Section 3 Some flexibility is available on a case-by- case basis Planning rules are reviewed from time-to- time

Output - Assignment Instructions Specific to each band Typical use Assignment priority Minimum path length Antenna Requirements Notes

Example : Refer to Appendix 11 Antenna Requirements

Output - Assignment Restrictions Identifies constraints placed on assignments Could be channel or geographic location specific May express additional coordination requirements May require application of special conditions or advisory notes to licences

Output - Protection Ratio Sets minimum ratio of wanted signal to unwanted signal (W/U) Sets the maximum level of unwanted (interference) signal level Minimum C/I for victim link BER Allowable BER degradation Fade margin (multi-path or rain) required on wanted link (outage time) NOTE Protection Ratios in FX3 are default values - real performance parameters of equipment can be used

Frequency Coordination Determines the compatibility of a proposed new fixed link service with existing services operating on a particular channel frequency in a given geographic area Focus is on the wanted signal to unwanted signal ratio (protection ratio)

Required Data Preferred frequency band Geographic coordinates of link ends System type / capacity / emission details Nominal mean emission power Antenna type and characteristics

Coordination Problem TX(f1) RX(f1) TX(f1) A B C D A B - Existing service route C D - Proposed service route A D and C B - Interference path

Basic Coordination Steps Identify potentially affected existing fixed services Calculate wanted and unwanted (interference) levels to / from proposed and existing fixed services Compare levels against the interference management criteria (protection ratio) Check compliance with assignment instructions and policy requirements Check compliance with sharing requirements for other services

Questions