A Delay Sensitive Time Slots Scheduling in Vehicular Sensor Networks

Abstract

In Vehicular communication networks, a robust access mechanism is essential for the successful information exchange between vehicles and roadside unit, which keeps the vehicles being aware of surroundings thus improving driving safety and reduce traffic jam. In this paper, we first analyze the drawbacks of explicit GTS (Guaranteed Time Slots) allocation suggested by IEEE 802.15.4 draft and show the importance of a wise assignment scheme and efficient scheduler especially for high dynamic vehicular environment. Then, for a given number of vehicles requesting to access the roadside unit, we propose a Time-Sensitive Weighted Round Robin scheduler (TS-WRR) considering different service delay requirements, packets arrival rates and vehicles' mobility levels. We also show the elaborate implementation procedure of TS-WRR by pseudocode. Numerical results show that our TS-WRR scheduler outperforms FCFS and WRR on the performance of transactions delay requirements guarantee and GTS utilization ratio in Vehicular Sensor Networks.

Multichannel assignment using K-Means in cognitive radio networks

“…This can be understood as an opportunity to improve the type of service for the users of wireless technologies, who will make an opportunistic use of the available spectrum as a consequence of having a better spectral efficiency (Hernández, Páez & Giral, 2017;Chen, Wei, Jin, & Ge, 2013). These spectral opportunities are variant resources in the frequency-time domain, which the secondary users (SU) can use until the primary user (PU) requires once again the portion of the spectrum that the SU are using in order not to generate interference in the transmissions.…”

Partition-Based GTS Adjustment for Wireless Sensor Networks

“…Simulation results showed that the proposed GTS scheduling improved the guaranteed real-time transmission, bandwidth utilization, and energy efficiency. Chen, et al [9][10] have proposed the Time-Sensitive Weighted Round Robin (TS-WRR) scheduler for the GTS utilization ratio in vehicular sensor networks. The numerical result using Matlab and Opnet showed that the GTS utilization of the TS-WRR algorithm was better than without time-sensitive scheduler.…”