Max Ehammer

B-AMC a system for future broadband aeronautical multi- carrier communications in the L-BAND

The Broadband Aeronautical Multi-carrier Communications (B-AMC) system is a candidate for a future aeronautical communications system to be operated in the L-Band (960-1164 MHz). It is based on the Broadband-VHF (B-VHF) system recently developed for aeronautical communications in the VHF band. As conditions in the L-Band significantly differ from those in the VHF band, basic physical layer parameters had to be adapted, which in turn required a re-design of the higher layers as well. B-AMC offers air/ground (A/G) as well as direct air/air (A/A) communication capabilities without ground relay. The physical layer has been designed to coexist with other systems located in the aeronautical L-Band. The B-AMC data link layer is optimized for low latency and low duty cycle data communication. The B-AMC study is funded by EUROCONTROL.

B-AMC — broadband aeronautical multi-carrier communications

The broadband aeronautical multi-carrier communications (B-AMC) system is a promising candidate for the future L-band radio system called L-band digital aeronautical communications system (L-DACS). In this paper, the design of the physical (PHY) as well as of the data link layer (DLL) is addressed. As B-AMC is intended to be operated in the L-band between two adjacent distance measuring equipment (DME) channels, the avoidance of mutual interference between existing L-band systems and B-AMC has been in the focus of the PHY layer design. In order to demonstrate the feasibility of the coexistence with DME, a draft frequency planning has been performed for Europe, resulting in successful frequency assignments in wide parts of Europe. The B-AMC DLL supports data link communication with low latency and high throughput. It is designed to be highly configurable and to support different service requirement sets and traffic profiles. In this paper, the current DLL configuration featuring a low RL duty-cycle and graceful degradation is discussed in detail.

L-DACS 1 data link layer design and performance

The VHF COM band currently used for air-ground communications is becoming congested, and the future Air Traffic Management concepts will require much greater use of data communications than today. The wireless communication system discussed in this paper, L-DACS1, is considered a candidate system for this purpose. It has been derived from B-AMC, TIA-902 (P34), and WiMAX (IEEE 802.16e). The presented work, which was performed in a EUROCONTROL funded study, aimed at developing an initial system specification for L-DACS1. This system specification shall enable prototyping activities that in turn shall clarify system compatibility issues that could not be covered analytically or via modeling.

Newsky - building a simulation environment for an integrated aeronautical network architecture

The expected evolution of aircraft traffic in the next decades and the foreseen lack of communication resources in the European airspace produce an increased need for efficient data communications. Up to now the general trend has been the implementation of new communication links and the optimization of existing resources. However, the main goal of NEWSKY is to integrate different communication technologies into a global IP based aeronautical inter-network The NEWSKY approach tries to achieve improved communication capabilities through a network centric service oriented architecture. In order to evaluate this future aeronautical inter-network it is imperative to define new simulation environments. The primary intent of our work is to develop a simulation environment which is capable of evaluating algorithms designed for a heterogeneous mobile network environment, laying the main focus on the evaluation of mobility and connectivity management concepts. The secondary objective of this work is to integrate the effects of self separation algorithms, medium term conflict detection and resolution, and collision avoidance systems into the concept of the simulation environment. This paper introduces a set of fundamental concepts to the simulation of integrated aeronautical communications architectures. NEWSKY is funded by the European Commission within the 6th framework program.

Applying SOA concepts to the simulation of aeronautical wireless communication

The aeronautical environment will change significantly in the near future creating an increased need for efficient data communication. Although the general trend of the expected transformation is predictable, the details are subject to highly dynamic changes. Consequently simulations within this environment have to be able to reflect alternating requirements. By the application of service oriented architecture concepts a simulation suite robust against changing requirements has been developed. It is the intention of our work to achieve this goal, while keeping the architectural complexity low and fostering the incorporation of existing simulation tools. Additionally this approach allows the decomposition of complex simulation challenges into simpler sub-tasks; large scale simulations are easy to conduct through distributed processing. However, the gain of lower complexity is bought by a certain loss of computational performance. This paper presents an application of SOA principles to the simulation of aeronautical wireless communication. The simulation architecture used for the assessment of the B-AMC aeronautical communication technology is described in detail.

Architecture of an IP-based aeronautical network

The International Civil Aviation Organization (ICAO) has defined a mobile IPv6-based Aeronautical Telecommunications Network (ATN/IPS) as a next generation communication network for future Air Traffic Management (ATM). The ATN/IPS will be used with different terrestrial and satellite link technologies for supporting future ATM. In parallel, non-operational services will use different link technologies as well. In such an environment, the main challenge is to design a network architecture that integrates all link technologies in a way that mobile users (be it a cockpit user or a passenger) can make use of them in a seamless way. This paper presents the core functionalities developed within the NEWSKY project of such an integrated IP network architecture.

The operation of TCP over aeronautical networks

Future initiatives on enhancing the current air traffic management (ATM) system aim at the integration of various communication systems enabling network centric operations. Therefore, reliable communication protocols and capable communication systems have to be provided in order to realize the eager goals of programs like SESAR and NextGen. Theoretically there are several possibilities where to place the reliable communication protocol but a main idea of the future aeronautical communication network is to use commercial of the shelf products (COTS). Thus, as it seems, there remains only a single candidate protocol, which TCP - a protocol in widespread use over the whole planet, used by millions of internet users from day to day. It seems reasonable to consider the use of TCP in aeronautical networks as well however, there is one major drawback when using TCP over lossy, narrow band, and slow wireless communication links - it does not perform as well as over high-speed broadband interconnected wired networks. This paper investigates several possible options to TCP use in the aeronautical environment.

Communication capacity assesment for the Iris satellite system

The Iris/ARTES 10 programme of the European Space Agency (ESA) aims to develop a satellite system for air traffic services (ATS) and aeronautical operational control (AOC) complementing the existing and future aeronautical communications infrastructure. This paper presents the approach to and the results of the Iris communication capacity assessment conducted in the first phase of the programme. The approach discussed within this paper is based on a combination of the message exchanges defined in the ldquocommunications operating concept and requirements for the future radio systemrdquo document (COCR) of EUROCONTROL and FAA and realistic air-traffic scenarios. The generated voice, data and air traffic is intended for two major purposes: first to identify capacity and protocol requirements for the design of the Iris communication system and secondly as input for the system performance evaluation.

Final Assessment of the B-VHF Overlay Concept

B-VHF is a proposal for a future aeronautical communication system in the very high frequency (VHF) band based on an overlay concept, i.e. during the transition phase the B-VHF system shares the same frequency band with legacy VHF systems without interfering with them. In this paper, the feasibility of the overlay concept is evaluated by simulations of the physical and higher layers as well as by laboratory measurements with a demonstrator. Simulation results show that the B-VHF overlay system works in presence of interference from legacy VHF systems. The protocol is designed to allow using the available resources very efficiently and to provide voice and data services with the required quality of service. In addition, the impact of mutual interference between the B-VHF system and legacy VHF systems is evaluated in laboratory test with a simplified B-VHF demonstrator and commercial VHF radios.

TCP/IP over aeronautical communication systems — Effects on bandwidth consumption

The TCP protocol has been selected as the transport layer protocol of the ATN/IPS. However, there are multiple known deficiencies of the protocol when operating over ldquolong thin networksrdquo. In this paper we discuss several well-known TCP optimization techniques and their application to aeronautical data traffic. The performance of TCP is evaluated and analyzed in a simulated environment based on the COCR report.