# Retracted: W-GPCR Routing Method for Vehicular Ad Hoc Networks
## 2 Materials and Methods
### Greedy Forwarding Strategy Based on Weight Selection
#### 2.1.1 Influence of Node Movement Direction on Routing Performance
If the weight of the neighbor node is greater than the weight of the current node, the data packet is sent to the node; otherwise, the current node carries the data packet. ### Weight Selection Repair Strategy

When the distance from the current node to the target node is less than the distance from its neighbors to the target node, the greedy forwarding strategy will be invalidated, and the repair strategy will be executed. The traditional repair strategy uses the right-hand rule to deliver data packets, as shown in Figure 3. Node A sends a data packet to node F, traverses its neighbors in a counterclockwise direction according to the right-hand rule, and repeats until the data packet reaches the target node or meets the condition of greedy forwarding to leave the repair strategy. The link path obtained by delivering the data packet according to the right-hand rule in Figure 3 is A-B-C-D-F. However, in some scenarios, data packets are delivered according to the right-hand rule, and the data packets are delivered far away from the target node. This will result in the unsuccessful delivery of the data packet to the destination, resulting in communication failure. Therefore, the weight calculation formula under the repair strategy is proposed. When the restricted greedy forwarding strategy fails, the data packet is delivered to the intersection node in the street direction. The intersection node will calculate the weights of all neighbor nodes within its signal coverage. By calculating the weights of all neighbor nodes within the signal coverage of intersection nodes, the neighbor node with the highest calculated weight will be selected as the next-hop node, thus solving the problem associated with the right-hand rule. \[R_{n}=r_{1}(1-\frac{D_{nd}}{D_{pd}})+r_{2}\cos(l_{pn},l_{pd}^{\rightarrow})+ r_{3}\frac{neig_{n}}{S} \tag{2}\]

where \(l_{pn}^{\rightarrow}\) is the vector representation of the current node pointing to the next-hop node; and \(l_{pd}^{\rightarrow}\) is the vector representation of the current node pointing to the target node. The value \(\cos(l_{pn}^{\rightarrow},l_{pd}^{\rightarrow})\) is used to judge whether the direction of the selected next-hop node tends to the direction of the target node. A larger value of \(\cos(l_{pn}^{\rightarrow},l_{pd}^{\rightarrow})\) indicates that the delivery direction of the data packet tends to

Figure 3: Delivery of data packets according to the right-hand rule. the direction of the target node. \(r_{1},r_{2},r_{3}\) is the weight proportion of the three reference quantities: \(r_{1}\) is the weight proportion of the distance between the nodes, \(r_{2}\) is the weight proportion of the cosine of the packet delivery direction and the target node direction, and \(r_{3}\) is the weight proportion of the node density; \(r_{1},r_{2},r_{3}\in[0,1]\) and \(r_{1}+r_{2}+r_{3}=1\). Under the repair strategy, the distance between the nodes is no longer used as the main reference, but depends on whether the packet delivery direction converges toward the target node. The distance between the nodes and the node density are used as auxiliary references, set as \(r_{1}<r_{2}\) and \(r_{2}>r_{3}\). \(R_{n}\) is the weight value of the next-hop node under the weight selection repair strategy. By calculating the weight value of each neighbor node, the neighbor node with the largest weight value will be selected as the next-hop node. The calculation of the weight value and the selection of the next-hop node also use Algorithm 1. As shown in Figure 4, the source node A sends a data packet to the target node H. When the data packet is delivered to the intersection node C, according to the right-hand rule to select the next-hop node, node D will be selected as the next-hop node. The routing path planned by the right-hand rule is A-> B-> C-> D-> E, which will cause the data packet to be delivered away from the target node. According to the weight formula mentioned in this article, \(R_{K}\)\(\in R_{D}\) is obtained through calculation.