Use of Satellite-based Technologies to Enhance safety and efficiency in ATC and Airport Operation Presented by Felix Tsao Senior Electronics Engineer Civil Aviation Department 26 May 2017 1
Briefing on Next Generation Surveillance Technology (ADS-B) 2
Briefing on ADS-B Automatic Dependent Surveillance Broadcast Automatic Dependent Surveillance Broadcast No interrogation is needed Depend on data from aircraft s navigation system Transmission of surveillance data Broadcast to everyone in range 3
Basic Principle of ADS-B Uses the Global Navigation Satellite System (GNSS) receiver in the aircraft to determine aircraft position No direct measurement of aircraft position by ground equipment Broadcast automatically from aircraft (Twice per second) No interrogation is required to trigger the transmission Data includes Aircraft Position Pressure Altitude Identity Other aircraft status (speed, heading, etc.) 4
Comparison between ADS-B and Radar 5
Basic Principle of RAdio Detection And Ranging (Radar) Uses electromagnetic (EM) waves to identify the range and bearing of objects being detected N Bearing Continuously Rotating Antenna (12 r.p.m. ) ~5 seconds update rate Primary Surveillance Radar (PSR) Secondary Surveillance Radar (SSR) Distance = (Speed of electromagnetic wave X time) 2 6
ADS-B Operating Principle GPS Signals ADS-B Message ADS-B Ground Station ADS-B data Air Traffic Control Centre 7
Scale of Ground Equipment Tai Mo Shan Radar Radome Omni-directional ADS-B Antenna 8
Advantages of ADS-B over Radar Accurate position information From GNSS (GPS) signals Easy to maintain No mechanical movement No transmitter Cost effective Less expensive to setup/maintain Fast update rate Typically every 1 second Able to provide low-level surveillance coverage ADS-B Radar High update rate is particularly useful to ATC in handling air traffic in complex and busy airspace 9
ADS-B Coverage in Hong Kong 10
ADS-B Ground Station Sites in HK Backup by Sites Better overall coverage while ensuring high availability 990mPD 474mPD 474mPD 65mPD 554mPD 536mPD 250mPD 101mPD Existing Radar Site Aim at low-flying traffic below 3000ft En-route Surveillance: 2 Sites Low-level Surveillance: 6 Sites
Combined ADS-B Coverage of Hong Kong Flight Information Region (FIR) 300NM Hong Kong ADS-B Coverage Hong Kong Hong Kong FIR Sanya Sanya FIR 12
Combined ADS-B Coverage of Hong Kong FIR Combined ADS-B at FL290 (can reach 280NM) Combined ADS-B at FL400 256NM 256NM Hong Kong FIR Hong Kong FIR Supplement radar to provide reliable surveillance coverage to ATC for maintaining aircraft separation 13
Signal Interference in Surveillance Data 14
FLT002 F380 Limitation in Radar technology (Signal Garbling) Caused by overlapping replies from close aircraft Radar Display FLT001 F400 Garbled Radar Signal Potentially lead to conflict alerts with genuine aircraft targets and cause nuisance to ATC FLT001 FLT002 FLT002 F380 FLT001 F400 Aircraft with close range and bearing Radar Replies from 2 aircraft overlap causing garbled data Garbled Radar Signal 15
Handling of Signal Interference in ADS-B ADS-B Information broadcast in an omni-directional manner randomly from aircraft without the need of interrogation Lower chance of overlapping signals from aircraft at close range Data verification done at ADS-B ground station Ensure data integrity of received ADS-B information Minimize the possibility of causing nuisance to ATC due to signal interference on the surveillance data 16
ADS-B Implementation in Hong Kong 17
ADS-B Implementation in Hong Kong ADS-B mandate for aircraft flying FL290+ within HKFIR effective on 8 December 2016 ADS-B Equipage More than 96% of aircraft are ADS-B equipped with accurate position report transmission Adopted phased implementation approach in accordance with the ICAO s Safety Management System (SMS) to manage changes/risks and ensure safe and smooth ADS-B implementation. 18
ADS-B Implementation in Hong Kong ADS-B coverage over holding patterns and ELATO area Aircraft usually fly at close distance but separated vertically Effectively reduce nuisance to ATC due to radar signal garbling ADS-B Coverage over CANTO, BETTY and ABBEY Holding Patterns ADS-B Coverage over ELATO ADS-B Airspace 19
ADS-B Implementation in Hong Kong Future Plan Gradually expand ADS-B operation to fully integrate with the new Air Traffic Management System in late 2017 after all safety assessment are satisfactorily completed 20
Conclusion 21
Conclusion To continue monitoring the performance of ADS-B closely; To gauge views from frontline ATCOs for optimising operational procedures and hardware; and To be prepared for full integration of ADS-B in the new ATMS in a progressive manner in 2017. 22
Thank you 23