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A 150W high power amplifier (PA) with an operating frequency range of 2.3 — 2.55GHz and high efficiency feature is proposed in this paper. The load pull and source pull technology is used to determine the best input and output impedance at maximum power output point, and the broadband matching of input and output impedance is completed by the method of parallel capacitance and microstrip line. When the PA design is completed, the structural parts are designed to ensure that the PA works in a good heat dissipation state. The drain efficiency of the PA is up to 53%, and the output power is 52 dBm, what's more, the in-band gain fluctuation is less than 2dB. Within the range of 6 dB of power back-off, the PA efficiency always stays in the range of 50%∼53%. This Doherty PA can be a good candidate for sub-6 5G applications.

Airport navigation lights are an important guarantee for flying at night and in complex weather conditions. The stability and reliability of the lighting system directly affect flight safety. However, due to the large number and the wide range of navigation lights, the manpower and material resources required for the inspection of the entire airport are huge, and the manual inspections are likely to cause problems such as missing investigations, mis-examinations, and statistical errors, which will directly affect the safety of the entire airport. At the same time, since the outer casing and the lamp holder of the navigation lights are made of metal, the wireless transmission capability of the monitoring device is required to be stronger. Therefore, the conventional monitoring method and the wireless communication method cannot meet the requirements of the navigational light monitoring system. The low-power wireless monitoring method and communication mechanism of navigational lights in the shielding environment can enable the battery-powered monitoring device to realize the long-term monitoring of the navigation light state in the shielding environment and upload the data to the cloud platform.

Wireless sensor networks (WSNs) with one static sink often suffer from energy hole problem, which means energy consumption of certain sensors near the sink or on critical path is much faster than other sensor nodes. Finally, network partition and isolated nodes are caused. To solve this problem, we propose an Energy-Efficient Strategy Enhancing Lifetime for WSNs based on MECA and PEGASIS. This algorithm aims at minimizing and balancing energy consumption for all sensor nodes and cluster heads. We divide the network into several equal clusters and the intra-cluster routing exploits multi-hop routing to save energy. The cluster heads will connect a chain such as PEGASIS, which can avoid distant cluster head from sending data to the sink node. Simulation results show that our proposed routing algorithm consumes much less than traditional routing algorithm like LEACH.