Message Scheduling for the FlexRay Protocol: The Static Segment

In recent years, time-triggered communication protocols have been developed to support time-critical applications for in-vehicle communication. In this respect, the FlexRay protocol is likely to become the de facto standard. In this paper, we investigate the scheduling problem of periodic signals in the static segment of FlexRay. We identify and solve two subproblems and introduce associated performance metrics: 1) The signals have to be packed into equal-size messages to obey the restrictions of the FlexRay protocol, while using as little bandwidth as possible. To this end, we formulate a nonlinear integer programming (NIP) problem to maximize bandwidth utilization. Furthermore, we employ the restrictions of the FlexRay protocol to decompose the NIP and compute the optimal message set efficiently. 2) A message schedule has to be determined such that the periodic messages are transmitted with minimum jitter. For this purpose, we propose an appropriate software architecture and derive an integer linear programming (ILP) problem that both minimizes the jitter and the bandwidth allocation. A case study based on a benchmark signal set illustrates our results.


Message Scheduling for the FlexRay Protocol: The Dynamic Segment
Schmidt, Şenan Ece; Schmidt, Klaus Verner (Institute of Electrical and Electronics Engineers (IEEE), 2009-06-01)
The FlexRay communication protocol is expected to be the de facto standard for high-speed, in-vehicle communication. In this paper, we formally investigate the scheduling problem for the dynamic segment (DS) of FlexRay. We take the bounds on the generation times and the timing requirements of the signals into consideration to propose a reservation-based scheduling approach that preserves the flexible medium access of the DS. To obtain efficient schedules, we formulate a nonlinear integer program- ming probl...
FlexRay protokolu statik bölütü için mesaj çizelgelenmesi
Schmidt, Ece Güran; Schmidt, Klaus Verner (2008-11-26)
Son yıllarda zamanlamanın kritik olduğu uygulamalar için veriyolu tabanlı araç içi haberleşme protokollari geliştirilmiştir. FlexRay protokolünun bu protokollar arasında fiili standard olması beklenmektedir. Bu makalede periyodik mesajların FlexRay statik bölüt’ünde (static segment) olan bant genişliğini en verimli kullanacak şekilde çizelgelenmesi problemi incelenmektedir. Bu amaçla uygun bir sistem mimarisi önerilmekte, basarım ölçütleri tanımlanmakta ve bir tamsayı doğrusal programlama problemi oluşturul...
Transmit Precoding for Flat-Fading MIMO Multiuser Systems With Maximum Ratio Combining Receivers
Coskun, Adem; Candan, Çağatay (Institute of Electrical and Electronics Engineers (IEEE), 2011-02-01)
We examine the application of transmit precoding in multiuser multi-input-multi-output (MIMO) communication systems with maximum ratio combining (MRC) receivers. In many multiuser applications, the maximum-likelihood or minimum mean-square error (MMSE) receivers can be prohibitive to implement due to their high implementation complexity. We examine the performance of the system with simple MRC receivers and carefully selected precoders, which are designed to compensate the lack of high-complexity receivers,...
Energy efficient wireless unicast routing alternatives for machine-to-machine networks
Tekbiyik, Neyre; Uysal, Elif (Elsevier BV, 2011-09-01)
Machine-to-machine (M2M) communications is a new and rapidly developing technology for large-scale networking of devices without dependence on human interaction. Energy efficiency is one of the important design objectives for machine-to-machine network architectures that often contain multihop wireless subnetworks. Constructing energy-efficient routes for sending data through such networks is important not only for the longevity of the nodes which typically depend on battery energy, but also for achieving a...
Systematic message schedule construction for time-triggered CAN
Schmidt, Klaus Verner; Schmidt, Şenan Ece (Institute of Electrical and Electronics Engineers (IEEE), 2007-11-01)
The most widely used standard for in-vehicle communication networks that interconnect electronic control units is the controller area network (CAN). However, the event-triggered architecture of CAN introduces several issues, such as predictability, signal jitter, and reliability. Different time-triggered networks. are being developed to address these issues. In this paper, we focus on time-triggered CAN (TTCAN), which achieves time-triggered behavior by implementing time-division multiple access on the exis...
Citation Formats
K. V. Schmidt and Ş. E. Schmidt, “Message Scheduling for the FlexRay Protocol: The Static Segment,” IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, pp. 2170–2179, 2009, Accessed: 00, 2020. [Online]. Available: