IMPULSE ADVANCED ALGOTRITHMS TO ASSESS THE IMPACT OF OBSTACLES ON PULSED CNS SYSTEMS

Transcription

1 ADVANCED ALGOTRITHMS TO ASSESS THE IMPACT OF OBSTACLES ON PULSED CNS SYSTEMS

2 Why IMPULSE? Air Navigation Systems work in an environment which is becoming increasingly complex: Largeurban and industrialdevelopmentaroundthe airportsurroundings. Challenging new improvements in airport facilities and buildings. A large deployment of wind turbines in order to support renewable energy. Lackof tools to analyse the impact on pulsed CNS systems: CW CNS systems are easily affected by multipath, but due to this fact, there are a lot of SW tools desinged to analyse these effects. This is not the case of pulsed signal CNS systems. Evolución de IMPULSE 08/03/2017

3 IMPULSE (Ineco Pulsed Systems Simulation Tool) IMPULSE predicts how a new obstacle may interfere with the existing pulsed signal systems, offering a view of the possible affected areas. This tool provides: A guidance for the search of new station sites. The range and power density coverage, given the terrain and possible obstacles. Possible perturbances around existing and planned stations. Multipath Error analysis for DME, PSR & SSR: TOA, Reflections, Power. Probability of Detection Reduction. Fresnel Ellipsoid Penetration. MLAT Systems DOP analysis. IMPULSE 08/03/2017

4 IMPULSE successfulstudy cases SPAIN TAIWAN OMAN UAE ü ü ü ü ü ü ü ü ü ENAIRE AESA Airbus - Getafe Aeronautical Study to relax the requirements of the Airport OLS Surfaces over the Kaohsiung Harbor (PHASE II) Study of affection of The Wave Muscat on CNS systems Maximum allowed building height analysis for Muscat city center shopping mall Aviation/Simulation study for OmanTel HQ Building at OCEC Fujairah Airport Concept of Operation and NAVAIDS Assessment Consultancy Services for Site Selection Study and Survey for the Installation of a New MSSR at Al Ain International Airport COLOMBIA ü New CNS systems for Eldorado airport new ATC Tower KUWAIT ü Kuwait International Airport Master Plan MOZAMBIQUE ü Support to the deployment of new CNS/ATM systems

5 Complex obstacles modelling IMPULSE allows modeling obstacles with different horizontal sections and different heights. Besides that, predefined obstacles are included: Windmills. Arcade. Panels. Fixed cranes. Mobile cranes. IMPULSE 08/03/2017

6 IMPULSE: Pulsed CNS Systems Impact Assessment Methodology Object Evaluation Infringe BRA? NO STEP 1 YES OLS Additional aeronautical Radioelectric Impact Study STEP 2 NO Acceptable? YES Reject Approval IMPULSE 08/03/2017

7 Step 1- Building restricted areas screening Impulse is capable of representing the Obstacle Limitation Surfaces defined in the ICAO annex 14, the Spanish Radioelectric Restricted Areas and the Building Restricted Areas (ICAO PT/BRA EUR DOC 015). Very useful for : o Searching new station sites. o Preliminary obstacle impact affection assessment. ICAO PT/BRA EUR doc 015 Second Edition (Sept 2009) European guidance material on managing Building Restricted Areas : guidance material for determining whether the physical presence of a building may have an adverse effect on the availability or quality of CNS systems signals in space. Two-step process to demonstrate it will not cause an adverse effect on the CNS facilities. IMPULSE 08/03/2017 7

8 Step 1- Building restricted areas screening IMPULSE IMPULSE 08/03/2017

9 Step 1- Building restricted areas screening IMPULSE

10 Step 2 Radioelectric Impact: Coverage Studies Two different types of analysis will be carried out: Broadcast analysis: the aim of this analysis is to illustrate an upper view of the coverage map of the system according to the specified FL. Several studies can be performed taking into account different MSL altitudes. Procedure analysis: line of sight coverage can be verified along procedures published in AIP, to determine the real impact on air traffic of coverage holes due to the new obstacle. Not only Line of Sight, but Power Density studies will be performed. Both the terrain and the new obstacles will be taken into account in both types of studies. 10

11 Step 2 Radioelectric Impact: Multipath Errors Studies The Pulsed CNS systems provide discrete interrogations and replies. For a multipath error to occur, three conditions are necessary: The reflected signal interferes the direct signal in the trajectory of aircraft. There is a small path difference between direct and reflected signal (TOA), and both signals overlap. The power of the reflected signal is comparable to that of the direct signal. POTENTIAL PROBLEM PROBLEM NO PROBLEM SIDE LOBE MAIN LOBE 11

12 Methodology to develop Radioelectric Impact Studies Step 2 Radioelectric Impact: Multipath Errors Studies This type of errors may happen when there is a small path difference between direct and reflected signal. Under these conditions (small path difference), the pulsed CNS system (PSR, SSR, DME) will receive a combination of both direct and reflected signal resulting in range and/or azimuth errors. IMPULSE is capable of assessing affected airspace areas where range and azimuth errors may happen. The tool will also indicate whether the procedures analyzed are within these areas, being therefore potentially affected. Colour Meaning Effect No reflected signal received Reflected signal received but below the height of the point Reflected signal received at the height of the point Reflected signal received at the height of the point & Beyond ISLS protection area Reflected signal received at the height of the point & Same azimuth than the direct signal Reflected signal received at the height of the point & Beyond ISLS protection area & Same azimuth than the direct signal None None Potential false target inhibited by the system False Target Range & azimuth error Critical error Ineco s Air Navigation Tools, Services & Training

13 Evolución de IMPULSE Multipathanalysis for DME Qualitative analysis - Especular reflections - Time Of Arrival calculation - Power estimation Potential problemarea Detailed analysis (quantitative) - Signal in space modelling - Reflection in terrain using geometrical optics - Reflection in obstacles using physical optics approximations - Signal processing in ground and on-board systems IMPULSE 08/03/2017

14 Evolución de IMPULSE How DME works? T=t1+t2+tp D=(T-tp) c/ x 10 t tp t x 10-5 IMPULSE 08/03/2017

15 Evolución de IMPULSE Problems in DMEs: reflections happen Received signal x x 10 x x Reflection in obstacle Direct signal Reflection in terrain IMPULSE 08/03/2017

16 Evolución de IMPULSE New DME evaluation process Signal generator: transmitter Receiver Distance information Lost reply Signal Processing Terrain Obstacle/s Signal processing Lost interrogation Receiver Transmitter Honeywell DME 37B Thales 415/435 IMPULSE 08/03/2017

17 Examples: Valencia DME : Multipath problems in RWY 30 landings Main obstacles were identified: - CESSNA hangar - Air Nostrum building - Terminal building

18 IMPULSE Examples: Valencia model with IMPULSE. Obstacles

19 Examples: Valencia model with IMPULSE. Maneuvres IMPULSE

20 Examples: Valencia model. Results (I) Calibration flight Not processed reply IMPULSE output Not processed reply

21 Examples: Valencia model. Results (II) Calibracion flight Distance information IMPULSE output Distance information

22 Examples: Dulles FAA paper: Investigation of Terminal Area Distance Measuring Equipment Signal Interference. A Case Study Multipath problems detected in 2009 Detected obstacles: Space Musseum Building complexes

23 Examples: Dulles Model with IMPULSE. Obstacles IMPULSE

24 Examples: Dulles Model with IMPULSE. Maneuvres IMPULSE

25 Examples: Dulles model. Results (I) Calibration flight Not processed reply IMPULSE output Not processed reply

26 Examples: Dulles model. Results (II) Calibration flight Distance information IMPULSE output Distance information

27 Thanks for your attention. Any question?