Kai Yang received the Ph.D. degree from Beijing Institute of Technology, China, in 2010. From 2010 to 2013, he was with Alcatel-Lucent Shanghai Bell, Shanghai, China. Now, he is a professor in the School of Information and Electronics, Beijing Institute of Technology, Beijing, China. His current research interests include resource allocation, convex optimization, massive MIMO, mmWave systems, and interference mitigation. Minwei Shi received the B.S. degree in information and computing science and the M.S. degree in communication engineering from the Beijing Institute of Technology, Beijing, China, in 2015 and 2018, respectively, where he is currently pursuing the Ph.D. degree with the School of Information and Electronics. His research interests include modeling and performance analysis of wireless communication networks.Hang Yuan received the B.S. degree in information engineering from the Beijing Institute of Technology, Beijing, China, in 2016, where he is currently pursuing the Ph.D. degree with the School of Information and Electronics. From 2017 to 2019, he was a visiting student with the Research School of Electrical, Energy, and Materials Engineering, Australian National University. His research interests include millimeter wave and terahertz communications.Zhitong Ni received the B.E. degree in information engineering from the Beijing Institute of Technology, Beijing, China, in 2017. He is currently working toward the Ph.D. degree with the Beijing Institute of Technology and the University of Technology Sydney, Ultimo, NSW, Australia. His research interests include array signal processing, angle-of-arrival estimations, and precoding techniques in various applications including the fifth-generation millimeter-wave communications and joint radar and communication (Rad-Com) systems.

• 1.Introduction.- 2.Decoupled Heterogeneous Networks with mmWave Small Cells .- 3.Performance Analysis of mmWave Cellular Networks with Hotspot.- 4.Fine-Grained Analysis of Clustered mmWave Networks.- 5.Hybrid Subarrays Based Angle-of-Arrivals Estimation for Millimeter-wave Systems.- 6.Hybrid Precoder Design with Minimum-Subspace-Distortion Quantization in Multiuser mmWave Communications.- 7.Hybrid Precoding for Wideband Multiuser Millimeter-wave Systems.- 8.Hybrid Precoding Towards Higher Frequency Systems.- 9.Summary and Discussion.

Kai Yang received the Ph.D. degree from Beijing Institute of Technology, China, in 2010. From 2010 to 2013, he was with Alcatel-Lucent Shanghai Bell, Shanghai, China. Now, he is a professor in the School of Information and Electronics, Beijing Institute of Technology, Beijing, China. His current research interests include resource allocation, convex optimization, massive MIMO, mmWave systems, and interference mitigation. Minwei Shi received the B.S. degree in information and computing science and the M.S. degree in communication engineering from the Beijing Institute of Technology, Beijing, China, in 2015 and 2018, respectively, where he is currently pursuing the Ph.D. degree with the School of Information and Electronics. His research interests include modeling and performance analysis of wireless communication networks.Hang Yuan received the B.S. degree in information engineering from the Beijing Institute of Technology, Beijing, China, in 2016, where he is currently pursuing the Ph.D. degree with the School of Information and Electronics. From 2017 to 2019, he was a visiting student with the Research School of Electrical, Energy, and Materials Engineering, Australian National University. His research interests include millimeter wave and terahertz communications.Zhitong Ni received the B.E. degree in information engineering from the Beijing Institute of Technology, Beijing, China, in 2017. He is currently working toward the Ph.D. degree with the Beijing Institute of Technology and the University of Technology Sydney, Ultimo, NSW, Australia. His research interests include array signal processing, angle-of-arrival estimations, and precoding techniques in various applications including the fifth-generation millimeter-wave communications and joint radar and communication (Rad-Com) systems.

• 1.Introduction.- 2.Decoupled Heterogeneous Networks with mmWave Small Cells .- 3.Performance Analysis of mmWave Cellular Networks with Hotspot.- 4.Fine-Grained Analysis of Clustered mmWave Networks.- 5.Hybrid Subarrays Based Angle-of-Arrivals Estimation for Millimeter-wave Systems.- 6.Hybrid Precoder Design with Minimum-Subspace-Distortion Quantization in Multiuser mmWave Communications.- 7.Hybrid Precoding for Wideband Multiuser Millimeter-wave Systems.- 8.Hybrid Precoding Towards Higher Frequency Systems.- 9.Summary and Discussion.

Kai Yang received the Ph.D. degree from Beijing Institute of Technology, China, in 2010. From 2010 to 2013, he was with Alcatel-Lucent Shanghai Bell, Shanghai, China. Now, he is a professor in the School of Information and Electronics, Beijing Institute of Technology, Beijing, China. His current research interests include resource allocation, convex optimization, massive MIMO, mmWave systems, and interference mitigation. Minwei Shi received the B.S. degree in information and computing science and the M.S. degree in communication engineering from the Beijing Institute of Technology, Beijing, China, in 2015 and 2018, respectively, where he is currently pursuing the Ph.D. degree with the School of Information and Electronics. His research interests include modeling and performance analysis of wireless communication networks.Hang Yuan received the B.S. degree in information engineering from the Beijing Institute of Technology, Beijing, China, in 2016, where he is currently pursuing the Ph.D. degree with the School of Information and Electronics. From 2017 to 2019, he was a visiting student with the Research School of Electrical, Energy, and Materials Engineering, Australian National University. His research interests include millimeter wave and terahertz communications.Zhitong Ni received the B.E. degree in information engineering from the Beijing Institute of Technology, Beijing, China, in 2017. He is currently working toward the Ph.D. degree with the Beijing Institute of Technology and the University of Technology Sydney, Ultimo, NSW, Australia. His research interests include array signal processing, angle-of-arrival estimations, and precoding techniques in various applications including the fifth-generation millimeter-wave communications and joint radar and communication (Rad-Com) systems.

• 1.Introduction.- 2.Decoupled Heterogeneous Networks with mmWave Small Cells .- 3.Performance Analysis of mmWave Cellular Networks with Hotspot.- 4.Fine-Grained Analysis of Clustered mmWave Networks.- 5.Hybrid Subarrays Based Angle-of-Arrivals Estimation for Millimeter-wave Systems.- 6.Hybrid Precoder Design with Minimum-Subspace-Distortion Quantization in Multiuser mmWave Communications.- 7.Hybrid Precoding for Wideband Multiuser Millimeter-wave Systems.- 8.Hybrid Precoding Towards Higher Frequency Systems.- 9.Summary and Discussion.