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The main aim of this study is to elaborately examine the error correction technology for global navigation satellite system (GNSS) navigation messages and to draw a conceptual decision support framework related to the modernization of the GNSS and other systems.

The extensive simulation model developed in Matrix Laboratory (MATLAB) is used to evaluate the performance of forward error correction (FEC) codes such as Hamming, Bose–Chaudhuri–Hocquenghem, convolutional, turbo, low-density parity check (LDPC) and polar codes under different levels of noise.

The performance and robustness of the aforementioned algorithms are compared based on the bit length, complexity and execution time of the GNSS navigation message. In terms of bit error rate, LDPC coding exhibits more ability in the robustness of the navigation message, while polar code gives better results according to the execution time.

In view of future new GNSS signals and message design, the findings of this paper may provide significant insight into navigation message modernization and design as an important part of GNSS modernization.

To the best of the authors’ knowledge, this is the first study that conducts a direct comparison of various FEC algorithms on GNSS navigation message performance against noise, taking into consideration turbo and newly developed polar codes.

The purpose of this paper is to explore the main Unmanned Aerial Vehicles (UAVs) projects proceeded by Turkey and to reveal the future targets and the status of Turkey among the countries securing enhanced UAV experience.

The historical development and the future of the UAV systems are analyzed by using the roadmaps, and reports about the UAV market.

It is found that the development and the production of indigineous UAV systems/subsystems will reduce the costs, and enable Turkey to be independent with respect to when, where, and how to use its own UAV systems.

This study provides historical context for recent developments in UAV sector in Turkey and presents some proposals for the future of the market.

The purpose of this paper is to develop an analytical approach for workload measurement based on the task times and the changing task priorities of en route air traffic controllers (EATC).

A model called Total Airspace Workload Measurement Model was developed to measure EATC workload. Turkish airspace was chosen for practical application of the model. A survey was conducted of EATC to calculate the weighting coefficients and times of different tasks defined in the model. The survey results were analyzed with SPSS 15.0. The real traffic data of Turkish airspace for two peak hours period in heavy traffic covering August 2007 was provided by the General Directorate of Turkish airports. Geomedia 6.0 was employed for the visualization of the real traffic data.

The total airspace workload during two peak hours of traffic, estimated reference sector capacity and the number of operational sector were defined and calculated to analyze the distribution of workload among sectors.

This study can be used for en route sector design such as decision of the number of operational sectors and planning of sectors capacity in the strategic level. Air traffic control service providers can also refer to this study for human resources and equipment planning.

A number of parameters and variables were defined and included in the model by taking into consideration the different service types provided by EATC. All parameters and variables were identified with the task times of the controller. This analytical approach can be applied to those particular airspaces which have different characteristics.