EQPT-2 Flashcards

Question

Qual o sistema que permite correlacionar pistas locais de diferentes sistemas surveillance como MSSR, WAM e ADS-B por exemplo e gerar Tracks de sistemas de utilização nas funções ATM?

Answer 1

ARTAS (ATM surveillance tracker and server )

Answer 2

Area Control Approach Control Aerodrome Control - Air; traffic integration, approach monitoring - Ground; Runway protection, monitoring ground hazards

Answer 3

By calculating the time taken for a signal of a known speed to be recevied as an echo we can calculate the distance using the following equation. Distance= (speed x time)/2 tendo em conta o slant range

Answer 4

Radio Detection And Ranging.

Answer 5

By sending out a pulse of electromagnetic energy and waiting for a reflection, as the speed of the wave is known (c) then the distance can be calculated easily. distance= (speed x time)/2 This tells us how far away the object is and by combining this with the information about which way the RADAR was facing when the signal was received we can determine the position of an aircraft as well.

Answer 6

Permanent Echoes These are the position indications given by permanent objects in the area of operation of a RADAR, they can be used to check that the RADAR is still correctly aligned.

Answer 7

Unwanted returns on a RADAR screen, these can be caused by ground, buildings, or weather (the rain droplets in clouds is what causes clouds to reflect RADAR)

Answer 8

The visual indication, in non symbolic form, on a situation display of an aircraft obtained by PSR.

Answer 9

The situation which exists when the RADAR position of a particular aircraft is seen and identified on a situation display.

Answer 10

Transmission Reception Display

Answer 11

Is a transceiver that can transmit and receive, but only does one or the other at a time.

Answer 12

The Pulse Repetition time The time between pulses necessary to receive a return from the unambigious range. ie how long would be needed between pulse replies to receive a signal from the RADARs maximum range. This determines the PRF

Answer 13

The pulse repetition frequency The number of pulses that can be trasmitted in a second. Higher PRF the greater the clarity of the position return displayed as you get more 'hits' on it.

Answer 14

Secondary Surveillance RADAR RADAR that works by the sending an interrogation signal to the aircraft transponder which sends a reply to the station. The distance is calculated by the time taken for the response to tbe received and the direction is taken from the direction the RADAR is facing. The response can also contain height and identity information as well.

Answer 15

The ground stations transmit the interrogation signal on 1030MHz Aircraft transponder sends the reply on 1090MHz

Answer 16

By sending a pair of pulses which are seperated by a certain time interval between each pulse. 8.5µs for Mode A 21µs for Mode C The aircraft will then recognise this and send back the appropriate information.

Answer 17

12 bits This limits the possible amount of codes to 4096 discrete codes

Answer 18

1. Discrete codes- Those assigned to individual aircraft 2. Non Discrete- Single codes issued to numerous aircraft ie conspicuity 3. Special codes- Applied to aircraft on certain occassions

Answer 19

Originating Region Code Assignment Method Codes are assigned depending on what participating area they come from. It is designed to reduce RTF and cockpit work-load by allocating an SSR code which can be retained from take-off to touchdown.

Answer 20

Codes assigned to individual positions to identify aircraft being controlled by a particular unit to another unit. Helps in coordinating between units.

Answer 21

11 this is because the numbers 8 and 9 are now required.

Answer 22

Position indications and position symbols may overlap making them impossible to read or even causing the mode A codes to be incorrectly displayed. Is conteracted by a de-garbler

Answer 23

False Replies Unsynchronised in Time Falses responses being received. Removed by a de-fruiter.

Answer 24

For a given aerial height this will improve the low coverage but decrease the higher coverage

Answer 25

For a given aerial height it increases the higher coverage but decreases the lower coverage.

Answer 26

It will cause it to attentuate faster and increase the atmospheric effect on the coverage. Due to increased interaction with molecules in the air.

Answer 27

Enough, allowing for attentuation, so that the RADAR can detect an echo from an aircraft at maximum range.

Answer 28

Moving Target Indicator This makes the RADAR screen display only those targets which are moving as the rest are filtered out. This helps to reduce PE's and clutter. However this relies on radial movement of the aircraft between pulses otherwise it appear stationary.

Answer 29

Selected It is a form of SSR that selectively interrogates aircraft instead of just generally interrogating them all. Individual interrogations reduces garbling and Fruiting. Allows each aircraft to have its own unique code.

Answer 30

1030-1090MHz same as all other SSR.

Answer 31

24 bits 16.75 million.

Answer 32

1. Operation Acquisition Phase- interrogator tracks conventional responders looking for new Mode S transponders and retains in its memory the individual addersses for the next phase. 2. Addressed survelliance phase- Mode S a/c individually interrogated for ATC identification, altitude, and other data.

Answer 33

Identification Squawk Level Position

Answer 34

``` Position Identifiction Flight level Selected altitude IAS Ground speed Mag heading RoC RoD ```

Answer 35

Automatic Dependent Surveillance Broadcast Works like a passive radar receiving signals from onboard equipment from the a/c. A/C deduces its own position and passes down to the ground station. Can also be used as a downlink to send and receive messages from the a/c or ground, much like CPDLC except it has less pilot input. Can allow non-procedural approach procedures in area of little or no RADAR coverage. Can also be used to augument RADAR coverage in areas of RADAR shadowing, eg hills/ mountains near an airport. * ADS-B broadcasts; horizontal position, vertical position, and velocity; as well as other information. * Can be used by aircraft or vehicles. * Also can be received by ground facilities. * Enables a passive system to monitor, uniquely identify, and track all targets in range. * Suitable for ground, and airborne application. (For sole-source surveillance) * Is reliant on ALL users providing accurate information ALL of the time. Automatic- Always on-No operator intervention Dependent- The system relies upon very accurate GNSS navigation data. Surveillance- Provides aircraft position, heading, speed, altitude, identification, and other data. Broadcast- No interrogation required. Data is broadcast to any ADS-B station. -It uses a downlink and messages can also be sent from the antenna to the a/c

Answer 36

- Relatively inexpensive, 0.01% the cost of equivalent RADAR - Smaller Power requirements and footprint, allows installation in remote areas. - Comms links are satellite and Microwave

Answer 37

Multilateration Very similar to ADS-B. MLAT antennae on the ground receive position reports from a/c via Mode S or ADS-B broadcast, the exact position is then worked out using TDOA (time diffrence of arrival) which uses the difference in receipt times of the signal between different antennae to work out the position. Displays on the Situation display in the same way as ADS-B Short range ones can be used to augument SMR, much cheaper and easier to maintain than SMR also more accurate and faster. Need several antennae to achieve necessary coverage. Wide area MLAT can be used to cover larger volumes of airspace. In augmentation with RADAR (which is sometimes impractical).

Answer 38

Aircraft and vehicles, must be equipped with transponders to be visible though.

Answer 39

Position Airborne Velocity Aircraft Identity

Answer 40

Automatic Dependent Survelliance Contract A 'contract' is established between the aircraft and the ground station. This contract establishes what reports the aircraft must make to the ground station and when they must be made. The ATSU will have to establish what type of contract is to be made before the ADS-C reports will be sent from the aircraft.

Answer 41

Periodic contract Demand contract- ATC will demand a report from the a/c now, such as a level report. Event contract- Aircraft is told to make a report when doing a certain thing eg vacating a certain flight level Mayday contract- only the pilot can cancel this one.

Answer 42

Advantages - Less power for similar range - No ground or weather clutter - Display and identification of aircraft simplified - Level Info - Emergency Squawk Codes - Can be equipped with safety nets (STCA etc) Disadvantages - All a/c need a transponder - No weather returns - Fruit - Garbling of TDB's - Fading - No permanent echoes for calibration

Answer 43

Aircraft and vehicles, must be equipped with transponders to be visible though.

Answer 44

Disadvantages - All a/c need a transponder - No weather returns - Fruit - Garbling of TDB's - Fading - No permanent echoes for calibration

Answer 45

Self contained Independent operation-solely provides identification and fix of the aircraft Non-reliant- A/C dont need a transponder You get PE's, which can be used to calibrated Weather Information

Answer 46

No level info Identification requires a much higher workload Weather clutter PE's can be obscuring Range depends on transmitter power, target size and properties No emergency indicator

Answer 47

A mode selected by the pilot that informs ATC that the aircraft is experiencing an emergency, including changing the squawk automatically. Only the crew can initiate and turn this off.

Answer 48

Horizontal Vertical Velocity

Answer 49

``` Aerial size, shape and height Size of the target Atmospheric conditions Transmitter power Receiver Efficiency PRF Pulse length ```

Answer 50

ADS B extended Squitter which transmits the aircraft information on 1090MHz