# Two-Level Sharing and Extraction of Sensing Information with Hybrid V2X Communications
## 1 Introduction
That is, based on the collection and summary of the distributed sensing data of different vehicles, the edge server selects a suitable data rate for the broadcast and makes an appropriate decision regarding broadcast time or channel selection. The second example is an edge server that collects the sensing information of free space between vehicles, which carries out a sensing of free space for other vehicles. Based on the collection and extraction of the sensing information of free space, the edge server assesses and predicts the safety status and performs maneuver coordination by an adjustment of vehicle speed and the distance between vehicles [11; 13]. reduces the number of reports from vehicles at the edge server in the extraction of sensing information from vehicles. Furthermore, the results show that the total amount of wireless resource consumption is highly reduced for the local sharing of sensing information among vehicles and the extraction of sensing information from the edge server. We find that only a few rounds of local exchange of sensing results with each vehicle are needed to improve the scalability of the reports sent to the edge servers. The general property of scalability of the proposed method is examined by mathematical analysis. The contributions of the paper are as follows. (1) From a functionality perspective, this paper examines the extraction of sensing information from vehicles at the edge server to extend sensing-perception. To enable the effective extraction of sensing-information from vehicles with a low traffic load at the edge server, we transform the extraction procedure into a two-level process that involves (a) the local sharing and extraction of sensing information among vehicles and (b) the global extraction of sensing information at edge servers. (II) From the perspective of communication efficiency, hybrid communication is utilized in the proposed method for the extraction of sensing information from vehicles. First, long-range wireless communication is utilized for communication between the edge server and vehicles in queries and reports of sensing information. Second, short-range wireless communication is utilized for the local exchange of sensing information among vehicles in order to reduce the consumption of wireless resources. (III) From the perspective of practical applications, a broadcast is employed at the vehicles for the sharing of sensing information between them. To increase the scope of the local sharing of sensing data among vehicles, the multiple-round exchange of sensing data is investigated. Meanwhile, the proposed method employs the constraint of maximum scope for the sharing of sensing data among vehicles and avoids the duplicated transmission of the same sensing data at each vehicle. (IV) We investigate and verify the efficiency of multi-round sharing and the extraction of sensing information among vehicles for the edge server to efficiently collect and extract the object sensing information. Furthermore, the general property of scalability of the proposed method is examined and verified via mathematical analysis. The remainder of this paper is organized as follows. Section 2 introduces the related work. Section 3 introduces the system model and motivation of the paper. Section 4 describes the proposed scheme. Section 5 describes the evaluation and numerical results of the proposed scheme. Section 6 introduces the discussion and future work, and Section 7 concludes the article.