Ground-based Augmentation System (GBAS) is a safety-critical satellite-based aircraft precision approach and landing system, and supports all phases of approach, departure, and surface operations. The ICAO Standards and Recommended Practices (SARPs) for GBAS provide the safety requirements, i.e. integrity, continuity, and availability, as well as the system accuracy. The ENRI GBAS ground prototype system (Category-I) was developed to realize the safety requirements through a safety design process based on the probabilistic safety assessment (PSA), and includes the integrity monitor algorithms (e.g. GPS satellite signal deformation, low power, code-carrier divergence, excessive clock acceleration, erroneous ephemeris broadcast, ionospheric delay) in the risk mitigation.

The purpose of this paper is to describe the summary of a safety design process including an example of integrity monitor algorithms, and a validation method for the safety assurance performed through the development of this system. This paper provides the worst-case simulation result of performance validation for the signal deformation monitor algorithm using the long-term real data which is collected by the prototype system installed at Kansai International Airport.

Flexible route systems have been operated in the airspace over Northern Pacific Ocean. PACific Organized Track System (PACOTS) is one of them. User Preferred Routes (UPRs) which is more efficient than PACOTS is the type of free routing and allows flight operators to tailor the route of each flight considering the effect of weather. Currently, PACOTS Track 2 UPR is prohibited in order to ensure the efficient and safe management of an orderly air traffic flow. Meanwhile, the number of aircraft that meet the criteria for applying reduced separation minima has been increasing. Since more opportunities to apply reduced separation minima are becoming available, it is worthwhile to reconsider the possibility of PACOTS Track 2 UPR.

This paper provides the results from computer simulation experiment of PACOTS Track 2 UPR. Whereas traffic concentration was occurred in PACOTS Track 2 entrance gateway, the results show an effectiveness of Track 2 UPRs basically, that may branch southward but are not permitted to re-converge on Track 2. The benefits come from trade off between disadvantage of flight altitude due to traffic concentration and effectiveness of flight time and fuel consumption reduction.

This paper describes a trajectory prediction model for future Air Traffic Management (ATM). International Civil Aviation Organization (ICAO) has created the global ATM operational concept scoping to 2025. Trajectory-based operation is introduced in the concept. The future vision of CARATS, NextGen and SESAR have progressed it. Electronic Navigation Research Institute (ENRI) has defined trajectory management as a core subject in its future research vision. A trajectory prediction system is necessary for trajectory management. ENRI has developed a trajectory prediction model.

This paper explained the trajectory prediction model as a means to predict and estimate the trajectory of an aircraft, a comparison of estimated trajectory with actual trajectory, and a simulation as time based operation for arrival traffic. The model predicts trajectories based on aircraft performance, airline operation, the navigation database, and weather forecasts. In order to attain the required accuracy, uncertainty factor analysis based on the actual flight operation environment is important. Trajectories predicted using the model are compared with actual operation data. Ground speed estimation is important for fix crossing time prediction. Error factors from the aircraft speed model and error factors from weather forecasts were analyzed for ground speed estimation. Analysis of weather forecasts shows good prediction of numerical prediction of Japan Metrological Agency. Improved aircraft speed model based on actual operation is proposed for good time prediction. Evaluation with the model shows good prediction performance in cruise phase and climb phase. Acquisition of speed intent of aircraft is important to predict trajectories. Arrival traffic simulation with the trajectory model shows fuel saving of speed control compared with pass extension.

ICAO (International Civil Aviation Organization) has proposed future aeronautical datalink candidates that have much higher transmission rates than VDL (VHF Digital Link). The candidates, which will be operated in L-band, are collectively known as LDACS (L-band Digital Aeronautical Communication System).

We have developed an LDACS physical layer experimental system, which is named LPES. The system is a test bed to evaluate BER (Bit Error Rate) performances under various conditions. LPES consists of PC and USRP (Universal Software Radio Peripheral) and its software is written in python scripts with the GNU Radio signal processing library. This paper describes some results of LDACS BER performances obtained with our LPES.