EQPS - Mode S Radar Flashcards
What is Mode S? (3)
- A co-operative surveillance technique for air traffic control.
- Ground based sensors, and airborne transponders.
- Operates in the same band (1030-1090MHz) band as conventional SSR systems
What does Mode S do? (6)
- Communicate with other A/C
- Unique Mode S address for each aircraft. (24-bit address)
- Allocated by the State at registration.
- An ‘address’ for Mode S radar (IC = Interrogator Code)
- Provided by the EUROCONTROL MICA (Mode S Interrogator Code Allocation) Cell
- Backward compatible with old systems. (Mode AC)
What does selective interrogation enable? (1)
A reduction in FRUITING and GARBLING
What is DAPS? (1)
Downlink Aircraft Parameters
What is SSR coverage limited by? (1)
Line of sight
How many codes does Mode-S give? (2)
- 16.75 million codes
- 24-bit address
What 2 stages is Europe implementing Mode S? (2)
- ELS - Elementary Surveillance
- EHS - Enhanced Surveillance
What are the basic functionalities of Mode S? (3)
- Altitude coded in 25ft increments.
- Indication whether aircraft is airborne or on the ground.
- Aircraft Identification (call sign) used for Elementary Surveillance.
Is IATA code compatible with Mode S? (1)
No
What is selective interrogation? (1)
Using the unique 24-bit address, attached to an individual airframe, ATCOs can select each aircraft individually, rather than having a Radar screen cluttered with labels
What does ELS do? (1)
Downlinks the call sign used in flight…
ATCOs can co-ordinate with an adjacent unit without referring to Mode-A codes
What does Elementary Surveillance DAPS provide the controller with? (3)
- Position
- Identification
- Altitude
“PIA”
What can Enhanced Surveillance can provide the controller with? (1)
ELS DAPs plus Heading + Speeds + Selected Altitude
What will Mode-S EHS support? (5)
- Automatic provision of airborne derived data to enhance ground systems functions including surveillance.
- Use of data link to improve efficiency of communications.
- Use aircraft derived data for ground based safety nets.
- Enhance ATC decision support by using aircraft derived data.
- Maintain and improve the quality of surveillance.
What are the 2 types of benefits of Mode-S EHS? (2)
- Safety benefits.
- Capacity benefits.
What does Mode-S EHS provide? (5)
- Early recognition of aircraft manoeuvres.
- Detection of level busts.
- Reduction in risk of communication errors.
- Improvement of safety by provision of a more precise prediction of horizontal and vertical aircraft behaviour.
- Improvement of safety in high density traffic areas through increased situational awareness.
What capacity benefits does Mode-S EHS provide? (7)
- Reduction of both controller and aircrew workload.
- Direct provision of up-to-date aircraft parameters to the controller.
- Extension of the domain of common reference for aircrew and controller.
- Reduction of voice channel occupancy.
- Improvement of the capacity of pre-regulation (e.g. sequencing) in terminal sectors.
- Reduction of the controller workload by reducing uncertainty concerning expected behaviour of the aircraft.
- Improvement of efficiency by allowing for more anticipation in planning of traffic.
What is MLAT? (2)
Mode S multilateration (MLAT):
Accurate surveillance and identification of all transponder equipped aircraft on the airport surface
What can Mode-S provide for TCAS? (3)
- Better exchange of data for collision avoidance
- An on-board computer retains positions, predicts future positions, and rate closure
- Calculates the closest point of approach (CPA) and produces a two-level warning of proximity
What is TDOA? (1)
Time Difference of Arrival
(measured by ground sensors)
What are the benefits of MLAT? (4)
- Independent
- Improved selection
- Complementary
- Increase accuracy
