Tight Approximation Ratios of Two Greedy Algorithms for Optimal RSU Deployment in One-Dimensional VANETs
Document Type
Article
Publication Date
1-1-2021
Abstract
For addressing the One-Dimensional Road side unit Deployment (D1RD) problem, a greedy approximate algorithm named Greedy2P3E was proposed two years ago, and its approximation ratio was proved to be at least 2/3 for the D1RD problem with EQual-radius RSUs (D1RD-EQ problem). Can better or even tight approximations for Greedy2P3E be found? In this paper, approximation ratio of Greedy2P3E is re-inspected and tight approximation ratio is found. To this end, a greedy algorithm named Greedy3P4 is first proposed and proved to have a tight approximation ratio of 3/4 for the D1RD-EQ problem. Then, by using Greedy3P4 as a bridge, 3/4 is also proved to be the tight approximation ratio of Greedy2P3E and it is tight for all n{\geq }2. Comparative evaluations are performed on real cases using a real vehicle trajectory dataset. The results show that these greedy algorithms usually return near optimal solutions with a profit more than 98% of the optimal solutions, and the greedy algorithms well outperform the other typical algorithms tested.
Publication Source (Journal or Book title)
IEEE Transactions on Vehicular Technology
First Page
3
Last Page
17
Recommended Citation
Gao, Z., Wu, H., Cai, S., & Tan, G. (2021). Tight Approximation Ratios of Two Greedy Algorithms for Optimal RSU Deployment in One-Dimensional VANETs. IEEE Transactions on Vehicular Technology, 70 (1), 3-17. https://doi.org/10.1109/TVT.2020.3045693