B-VHF - Selected Simulation Results and Assessment

Abstract

B-VHF is a proposal for a future aeronautical communication system in the 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 overlay concept is evaluated by simulations of the physical and higher layers. 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. The main goal of the B-VHF project is to verify the feasibility of a multi-carrier based overlay system for future air traffic control (ATC) communications in the very high frequency (VHF) band operating simultaneously with legacy VHF systems without causing interference. This approach enables in-band transition from the current to a future ATC communications system and, thus, allows future ATC communications to stay in the advantageous and protected VHF band. I IntroductionThe B-VHF overlay concept has already been presented at DASC 2004 [2], and in 2005, the physical (PHY) layer design of B-VHF has been detailed [3] with special emphasis on co-existence issues between B-VHF and the legacy VHF systems. At this year's conference, right after the end of the current project, the results of the B-VHF system simulations are presented and an assessment about the feasibility of the overlay concept in the VHF band is given.In a first step, the performance of the PHY layer is assessed using a set of realistic simulation scenarios. These scenarios comprise different channel conditions according to the different phases of flight, e.g., take-off and landing, taxiing, parking, or en-route flights. Moreover, realistic as well as worst-case situations for the interference from the legacy VHF systems towards the B-VHF system are taken into account.In a second step, higher layer protocol simulations are performed using the results from the physical layer simulations to model the B-VHF air interface, the interference situation in the VHF band, and the propagation conditions of the channel. Voice and different data applications are considered and the overall B-VHF system performance is assessed with respect to relevant system parameters like delay and throughput.The remainder of this paper is organized as follows. In Section II, PHY layer simulations are addressed. This section contains a description of the system model including the most important components specific for an overlay system as well as the considered simulation scenarios. Section III deals with the assessment of the developed data link layer (DLL) and higher layers protocols. In this section, the simulated system model and the simulation setup used for evaluating the protocols are described. In Section IV, simulation results for the PHY layer as well as for the DLL protocols are presented. In the last section, the B-VHF overlay concept is assessed and ...

Final Assessment of the B-VHF Overlay Concept

“…The second algorithm is a data aided maximum likelihood synchronizer that exploits information about the spectrum allocation available after the net entry phase. Simulation results in [8,9] have shown that the proposed synchronization algorithms work properly in presence of NBI.…”

“…10 presents our results for an En-Route 2015 scenario with high, medium, and low cell population (for a description of the simulation scenarios see [8] and the next section). The expected medium access delay increases almost exponentially as the amount of available slots decreases.…”

A Cybersecurity Architecture for the L-band Digital Aeronautical Communications System (LDACS)

“…All technologies are summarized in figure 1. LDACS was developed in cooperation between the German Aerospace Center (DLR) [5], [11], Frequentis AG [12], and the University of Salzburg in Austria [13], [14] with its origins in merging parts of the B-VHF [15], B-AMC [16]- [18], TIA-902 (P34) [33], and WiMAX IEEE 802.16e technologies [19].…”

Applying SOA concepts to the simulation of aeronautical wireless communication

“…B-AMC stands for Broadband Aeronautical Multicarrier Communications and is based on Broadband-VHF (B-VHF) [1,2]. B-VHF 2 was a feasibility study which demonstrated the suitability of multi-carrier based wideband technologies for aeronautical communications.…”