5G, as a new telecommunication generation, is growing rapidly. Meanwhile, problems occur. All previous telecommunication technology generations (from 1G to 4G) connect humans, but 5G aims at connecting objects. 5G has three axes: eMBB (enhanced Mobile Broadband), URLLC (Ultra Reliable Low Latency Communications) and mMTC (massive Machine Type Communications). Each of them has related specific use cases. The strict requirements posed by these targets imply high difficulty in 5G infrastructure deployment which will be discussed in this thesis. Besides, limited by the laws of physics, high-frequency waves used by 5G have smaller covering radii, which necessitate more antennas and more cells that lead to higher energy consumption. Energy-saving solutions are provided in this thesis for both hardware and software sides.