Название: Millimeter-Wave Networks: Beamforming Design and Performance Analysis
Автор: Peng Yang, Wen Wu, Ning Zhang
Издательство: Springer
Серия: Wireless Networks
Год: 2021
Страниц: 169
Язык: английский
Формат: pdf (true), epub
Размер: 19.1 MB

This book provides a comprehensive review and in-depth study on efficient beamforming design and rigorous performance analysis in mmWave networks, covering beam alignment, beamforming training and beamforming-aided caching. Due to significant beam alignment latency between the transmitter and the receiver in existing mmWave systems, this book proposes a machine learning based beam alignment algorithm for mmWave networks to determine the optimal beam pair with a low latency.

Then, to analyze and enhance the performance of beamforming training (BFT) protocol in 802.11ad mmWave networks, an analytical model is presented to evaluate the performance of BFT protocol and an enhancement scheme is proposed to improve its performance in high user density scenarios. Furthermore, it investigates the beamforming-aided caching problem in mmWave networks, and proposes a device-to-device assisted cooperative edge caching to alleviate backhaul congestion and reduce content retrieval delay.

Millimeter-wave (mmWave) communication at 30 GHz–300 GHz frequency bands has emerged as one of the most promising technologies in future wireless networks, which can offer high data rate connections by exploiting a large swath of spectrum. The mmWave communication can support many data-intensive wireless applications, ranging from high-definition mobile video streaming, cordless virtual reality gaming, to wireless fiber-to-home access. In particular, the current IEEE 802.11ad standard can provide a data rate up to 6.75 Gbps, and its successor IEEE 802.11ay can even support up to 40 Gbps. In mmWave communications, beamforming focusing the radio frequency power in a narrow direction is the key technology to overcome the hostile path loss. However, the distinct high directionality feature of beamforming technology poses many challenges in different network layers: (1) beam alignment (BA) latency in the physical layer, which is the processing delay that both the transmitter and receiver take to align their beams to establish a reliable connection. Existing BA methods incur significant latency on the order of seconds for a large number of beams; (2) medium access control (MAC) performance degradation. To coordinate the beamforming training (BFT) for multiple users, 802.11ad standard specifies an MAC protocol, i.e., BFT-MAC protocol, in which all the users contend for BFT resources in a distributed manner. Due to the “deafness” problem caused by directional transmission, i.e., a user may not sense the transmission of other users, severe collisions occur in high user density scenarios, which significantly degrades the MAC performance; and (3) backhaul congestion in the network layer. All the base stations (BSs) in mmWave networks are connected to the backbone network via backhaul links to access remote content servers. Although beamforming can increase the data rate of the fronthaul links between users and BSs, the congested backhaul link becomes a new bottleneck for mmWave networks.

This book concludes with future research directions in the related fields of study. The presented beamforming designs and the corresponding research results covered in this book, provides valuable insights for practical mmWave network deployment and motivate new ideas for future mmWave networking.

This book targets researchers working in the fields of mmWave networks, beamforming design, and resource management as well as graduate students studying the areas of electrical engineering, computing engineering and computer science. Professionals in industry who work in this field will find this book useful as a reference.