RFM2018 Tutorial session (17th December 2018)
Tutorial 1: : Antenna Measurement Techniques and Their Limitations for 5G
Due to the requirements of high date rate with massive machine type communications, low latency, and ultra-reliable, the data communication of 5th generation (5G) will be operated soon. The new techniques of 5G are adaptive to the following four items for different communication environments. The 5G techniques are adaptive to the (1) waveform and modulation, (2) new spectrum for sub 6GHz and millimeter, (3) flexible numerology, (4) massive MIMO and beamforming access. Since there are
not any RF connector in 5G millimeter wave, the measurement of 5G should be OTA (over the air) measurement. The beam patterns are sweeping for searching and fixed for data communication. The switching time from beam to beam is less than microsecond. The dwelling time of beam direction is adaptive to the required environment condition. In order to reduce the interferences, such as multipath and RF interferences, the pattern nulling can be adaptive to the interference directions. The beam patterns are complicated in 5G system. The challenges of OTA measurement for various techniques should be solved for low cost, low measurement time with high measurement accuracy. The tutorial talk will include the operation theory and limitations of the following three OTA measurement techniques.
1. Far field (FF) range and limitation
FF field range is the most common OTA measurement system for many antenna measurements. The quiet zone performance of FF range will depend on the distance between feed source and AUT, and multipath reflection for the complicated environment. The power loss is inverse proportional to the square of measurement distance. In order to reduce the quadratic phase error, the measurement distance should be large. Unfortunately, the power loss will be large with small quadratic phase error.
The examples of far field range for indoor and outdoor will be explained.
2. Near field range and limitation
The three dimensional far field pattern can be transformed from the measured three dimensional near field data. The spherical near field range is suitable for low directivity antenna. The cylindrical near field range is suitable for fan beam antenna measurement. The planar near field range is suitable for high directivity antenna measurement. The truncation error of near field range with limited near field scan area will degraded the test results. The multi reflections between near field probe and AUT should be as small as possible. Several types of near field range will be explained.
3. Compact antenna test range (CATR) and limitation
For the prime feed CATR, the feed phase center is located at the focus of offset paraboloid. The power loss is inverse proportional the square distance between feed phase center and reflection point of reflector. The wave reflected by the reflector is a plane wave. The size of quiet zone is about 1/3 of main reflector. For the traditional dual reflectors CATR, the subreflector is part of hyperboloid or ellipsoid and the main reflector is part of paraboloid. The power loss depends on the total distance among feed phase center, reflection point of subreflector, and reflection point of paraboloid. The size of quiet zone is around 1/2 of paraboloid. The quiet zone performance in higher frequency depend on For the prime feed CATR, the feed phase center is located at the focus of offset paraboloid. The power loss is inverse proportional the square distance between feed phase center and reflection point of reflector. The wave reflected by the reflector is a plane wave. The size of quiet zone is about 1/3 of main reflector. For the traditional dual reflectors CATR, the subreflector is part of hyperboloid or ellipsoid and the main reflector is part of paraboloid. The power loss depends on the total distance among feed phase center, reflection point of subreflector, and reflection point of paraboloid. The size of quiet zone is around 1/2 of paraboloid. The quiet zone performance in higher frequency depend on
the surface tolerance of reflector and in lower frequency depend on the edge diffractions. In order to reduce the edge diffraction, many serrated edges or rolled edges are arranged around the boundary of reflector. Examples of developed range will be explained. Except for the above three traditional measurement techniques, a new technique of generating multiple beam patterns, for 5G and for avoidance radars, without any scan loss in limited size of anechoic chamber will also be introduced in this talk.
About the speaker:
Prof. Chang, IEEE Life Fellow and EMA Fellow, is the Chief Scientist of Summit Worldwide Co., Ltd. He obtained his BS degree and MS degree from Chung-Cheng Institute of Technology, and Ph.D. degree in Electrical Engineering from University of Southern California. He spent 25 years in antenna R&D at CSIST (Chun Shan Institute of Science and Technology). For 17 of these years, he served as director of antenna section. During his employment at CSIST, he developed reflector antennas, phased array antennas, slot array antennas, communication antennas, and far field range, near field range, prime feed CATR, and dual reflectors CATR for the measurements of developed various kinds of antennas. In 1998, he left his post as director of the antenna section to become Dean of the Engineering School at Da-Yeh University. He had been invited to be the Dean of College of Electrical and Communication Engineering at OIT (Oriental Institute of Technology) in 2006. He has been the Chair Professor and Director of CRC (Communication Research Center) at OIT from 2006 to 2016. He has been established four laboratories during executing various research programs, lab of hybrid antenna near field antenna test range, lab of TRP/TIS communication measurement system, lab of EMC, and lab of EM simulation, at CRC of OIT. Except for various kinds of antenna research, Prof. Chang is also focus on the research on SI (Signal Integrity) with the funding support from Lorom Group. Since August 1, 2016, he changes his career from OIT to Lorom Institute of New Products Research and Development, Lorom Group. He has published over 400 papers at technical journals and technical conferences. Except for the technical papers, he also has more than 30 patents. Prof. Chang established the IEEE AP-S Taipei Chapter and as the first Chair in 2001, Chair of IEEE MTT-S Taipei Chapter and President of Chinese Microwave Association in 2000-2002. He has been the General Chair of CSTRWC2001, CSTRWC2008, ISAP2008, ICONIC2009, AEM2C2010, CSQRWC2012, PIERS2013, IEEE MTT-S IMWS-Bio 2015. He is the founding Chair of IEEE iWEM since 2011 and General Chair or Co-General Chair of IEEE iWEM.
Tutorial 2: An Overview of 5G Filtering – Challenges and Opportunities
The implementation of 5G has imposed great challenges in filter design due to the requirement of miniaturisation, reconfigurability, multiband carrier aggregation and interference control. The shift of spectrum to mm-wave/NR has also caused a significant impact onto the filter industry in terms of design techniques, prototyping and manufacturing capabilities. As such a cost effective and sustainable approach has to be developed in order to accommodate the need of various form factor and flexibility of filter design and implementation. This tutorial will give an overview of the 5G implementation highlighting the need of new design techniques for filter
innovation as well as the great opportunities unleashed for filter industry. Some of filter design techniques will be introduced to demonstrate the feasibility of implementation.
About the speaker:
Peng Wen Wong (M’05 – SM’17) graduated from University of Leeds in 2005 with BEng ( 1st Class Hons.) degree in Electrical & Electronic Engineering. He received Switched Reluctance Drive Award in EE Engineering. He did his PhD study in University of Leeds, UK from 2007-2009 fully funded by UK Ministry of Defense under DTC program . During his PhD, he was involved in UK DTI funded project, developing process design kits for multilayer system-in-package modules. Currently he works as Associate Professor in Universiti Teknologi Petronas and received outstanding researcher award in 2013, publication award in 2014 and Potential Academy Award of the Year in 2015. His research interests include reconfigurable filter, lossy filter design, millimeter-wave waveguide filter and passive filter miniaturization techniques. He has secured various research grants from government and industries since 2008 and published more than 80 papers including an article in IEEE microwave magazine. He serves as reviewer for IEEE Transaction on Microwave Theory and Technique, IEEE Wireless & Component Letter, IET Antenna & Propagation and PIERS. He was the former chair of IEEE ED/MTT/SSC Penang Chapter (2016 -2017) and founding chair of IEEE International Microwave, Electron Devices and Solid-State Symposium IMESS 2016. Dr. Wong has served as invited speakers locally and internationally including APMC 2017 and keynote speaker atICCSP2017. He is currently the advisor of IEEE Penang Joint Chapter and served as technical chair in IMESS 2017 and 2018. He is also the Associate fellow of AAET.