Abstract:
Abstract: As the wireless sensor network node's energy is limited, how to effectively use the limited resources and the effective transmission of data becomes a hot topic. In order to extend the life cycle of farmland wireless sensor network and improve the packet delivery rate of sensor network, a wireless sensor network suitable for farmland information collection was constructed, and a hybrid clustering routing algorithm (HCRA) was proposed in this paper. Two classical algorithms, LEACH (low-energy adaptive clustering hierarchy) and HEED (hybrid energy-efficient distributed clustering), were evaluated for their merit to extend life cycle of wireless sensors. In the LEACH algorithm, all cluster head nodes communicate directly with the sink nodes, so that energy consumption of the cluster head node far from the sink node was serious, and cannot guarantee the cluster head evenly distributed, which could make some cluster head nodes' energy consumption too large, affecting the network life cycle. The HEED algorithm, on the other hand, used the cluster head to communicate directly with the sink node, which consumed a lot of energy. Because the farmland information collection range was large, those two algorithms were not fully applicable to the wireless sensor network information gathering in farmland environment. Based on this evaluation and the principle of the HEED algorithm, we proposed a hybrid clustering routing algorithm (HCRA) for farmland information collection. In the proposed algorithm, the network model and the energy consumption models were described separately. In the network model, the monitoring area of the sensor network was abstracted as a circle area. Each node in the network had its own unique ID, and the location was not changed after the deployment was completed. All nodes were distributed evenly in the area. In the energy consumption model, the energy consumption of the wireless sensor network increased with the increase of the distance between the transmitting node and the receiving node, regardless of the power dissipation loss using the free space model or the multi-channel attenuation model. Besides, we also descried the HCRA algorithm in detail in this paper, including formation of cluster, cluster bidding and inter-cluster routing. The formation of the cluster was as follows: the center node sink was placed in the center position, and then from the sink node, taking r (the distance between layers and layers), 2r, 3r...as the radius, the entire circular area was divided into m flows. The entire area was divided into six parts, each of which was subdivided into small areas with equal area according to the number of layers. Each small area was a cluster in the wireless sensor network. The cluster head bidding process was as follows: the cluster head node was selected according to the heed algorithm, i.e., the cluster head was generated according to the initial probability of each node. When the cluster head was selected, other non-cluster head nodes joined the cluster selectively according to the collected information from the competition stage. The inter-cluster routing was the information transfer process between cluster heads, cluster head selected the next cluster head based on energy consumption. Finally, the proposed HCRA algorithm along with LEACH and HEED algorithm were simulated experimentally under the same conditions. The experimental results showed that the HCRA algorithm had 28% longer network lifetime than the LEACH algorithm, about 12% faster than the HEED algorithm, under the iteration period of 1000 times. The HCRA algorithm had a packet delivery rate, which was about 34 percentage points higher than the LEACH, and about 16 percentage points higher than HEED.