# The Latest Advances in Wireless Communication in Aviation, Wind Turbines and Bridges
## 5 Conclusions  
The work presents fundamental issues concerning wireless communication in structural health monitoring (SHM) systems in the context of Non-destructive testing (NDT) sensors. The use of wireless technology in aviation brings with it many challenges and problems. These include, for example, the implementation of the network architecture and the main communication protocols, such as:  
* Network architecture: the replacement of current avionics connections by wireless connections raises many questions about the clustering and topology of terminal systems and the mechanisms in place to avoid interference. * MAC protocol: The choice of the MAC protocol will have a direct impact on the timeliness and predictability of communications, which are paramount for secure avionics systems. Therefore, the MAC protocol ought to be well defined in order to meet this requirement. * Reliability mechanisms: In the case of critical avionics networks, the probability of failure should not exceed \(10^{-9}\) per flight hour. Therefore, this requirement should be met by every wireless system. The question that arises relates to the feasibility of a fully wireless avionics network or the necessity of backup. Moreover, avionics communication is mostly multi-media, which requires the integration of an improved confirmation and retransmission mechanism in order to reduce the communication load. Reliability mechanisms ought to be selected accordingly in order to meet these requirements. * Security mechanisms: Security is a critical criterion to be met for security-critical avionics applications. This is why the WAN must provide not only authentication, but also data encryption, and integration in order to avoid man-in-the-middle or DoS attacks. * Schedule analysis: In case of applications which are embedded in avionics, the communication network must meet the certification requirements, e.g., predictable behavior in harsh real-time conditions and time guarantees. However, wireless technologies can still increase communication delays because of transmission errors; therefore, it is necessary to verify real-time limitations in an error-prone environment. A lot of wireless systems are established and have features of proven quality. The development of wireless technology is high-speed and independent from the application platforms. This development's directions have to be carefully followed by application platforms to track the most suitable technologies. Wireless transmission is beneficial for  
Figure 14: Innovative wind power plant. remote control of the wind turbine and turbine farms. The choice of hardware platform depends on many conditions, such as:  
* necessary reliability and integrity of transmitted data;
* the distance on which transmission takes place;
* the expected amount of data which is to be transmitted;
* the acceptable delay time of data delivery;
* the necessity of the data transmission in two directions influences the turbine performance, stops the turbine, or modifies the generator loading algorithm. In recent years, energy suppliers have been incorporating cellular WAN technologies into power transmission and distribution. In this respect, a lot of \"best practice\" design guidelines have been introduced by the industry. Following these guidelines can allow industry stakeholders, utilities and power equipment manufacturers to achieve the best results from their wireless-enabled SCADA implementations. Because the technologies used in SHM systems based on wireless sensor networks undergo continuous development, the costs of the monitoring system's elements are falling, which will lower its total cost. In this situation, the challenge is to select the optimal number and network of sensors depending on the wireless system's other parameters and requirements. One of the main challenges for WSN is to ensure scalability to cover a large area. One of the main tasks is developing a procedure for shutting down unnecessary nodes to save power when no events are detected.