t due to the size constraint. With the use of HFSS software, authors built a MIMO antenna having improved isolation. An efficient four-element mm-wave MIMO (multiple-input multiple-output) antenna is being proposed for use in a 5G system. Chapter 12 covers the role of Terahertz photoconductive antennas in future healthcare informatics. In this chapter, THz generation and detection using various methods, starting from electrical, optical, and electro-optic methods has been described. However, the focus is given to PCA as it is the best possible way of THz generation and detection. For PCA, the classifications, equivalent circuital analysis, numerical simulations, and experimental characterization has been reported in detail. Taylor & Francis Taylor & Francis Group http://taylorandfrancis.com Acknowledgment Our efforts to produce a book in the evolving field of Advances of 5G Wireless Communication Systems in healthcare Informatics culminate efforts from sev- eral scientists, academicians, and practitioners across the world. The invited call for contributions in this fast-growing and rapidly evolving field has received an overwhelming response from the fraternity around the globe. A total of 44 proposals have been received for this book. Each of these proposal manuscripts has been thor- oughly checked and peer reviewed by at least three reviewers who are renowned experts in the respective topic. Based on the peer review outcomes and the suitability of the revised manuscript on the book's theme, 12 high-quality works have been chosen for final publication. We express our sincere thanks to all our reviewers for sparing their valuable time and sharing their expertise. We also express our sincere gratitude and best wishes to all the authors for contributing quality research work related to the book. We are also thankful to the New Horizon College of Engineering, Bengaluru (India), Indian Institute of Information Technology Kota (India), Malviya National Institute of Technology Jaipur (India) and Trakya University Turke