5G-A key technology is accelerating its development, but at present, its large-scale deployment in eMBB scenarios still has key challenges such as coverage, mobility, and multi-band cooperation. This document analyzes the typical characteristics of 5G millimeter wave, such as large bandwidth, high rate, low delay, high propagation loss, and penetration loss. Based on the characteristics and 5G-A key challenges, this document analyzes key technologies of 5G-A, such as narrow beam scanning, base station Multi-TRP, multi-panel terminal, and high and low frequency interoperability. Based on the characteristics of 5G millimeter wave and 5G-A key technologies, 5G-A typical application scenarios such as indoor and outdoor hotspot coverage, industrial manufacturing applications, and FWA are analyzed. Finally, two experimental networks are set up based on typical application scenarios, and the basic coverage and mobility performance of millimeter wave is verified and analyzed through the experimental networks, providing technical basis for promoting the large-scale deployment of 5G-A.