Wireless Communication Signals

A Laboratory-based Approach

Huseyin Arslan

• Publisher: Wiley
• Year: 2021
• Print ISBN: 9781119764410
• eBook ISBN: 9781119764434
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Mobile & Wireless Communications
• Index: Technology & Engineering

WIRELESS COMMUNICATION SIGNALS

A practical guide to wireless communication systems and concepts

Wireless technologies and services have evolved significantly over the last couple of decades, and Wireless Communication Signals offers an important guide to the most recent advances in wireless communication systems and concepts grounded in a practical and laboratory perspective. Written by a noted expert on the topic, the book provides the information needed to model, simulate, test, and analyze wireless system and wireless circuits using modern instrumentation and computer aided design software.

Designed as a practical resource, the book provides a clear understanding of the basic theory, software simulation, hardware test, and modeling, system component testing, software and hardware interactions and co-simulations. This important book:

• Provides organic and harmonized coverage of wireless communication systems
• Covers a range of systems from radio hardware to digital baseband signalprocessing
• Presents information on testing and measurement of wireless communication systems and subsystems
• Includes MATLAB file codes

Written for professionals in the communications industry, technical managers, and researchers in both academia and industry. Wireless Communication Signals introduces wireless communication systems and concepts from both a practical and laboratory perspective.

1
Hands-on Wireless Communication Experience

Hüseyin Arslan

Department of Electrical Engineering, University of South Florida, Tampa, FL, USA

Department of Electrical and Electronics Engineering, Istanbul Medipol University, Istanbul, Turkey

Due to the remarkable surge in wireless technologies as well as the introduction of new concepts like cognitive and software defined radios, a strong need for developing a flexible laboratory platform to teach a wide variety of wireless techniques has emerged. Laboratory benches equipped with flexible radio transmitters and receivers can address this goal. In this chapter, a laboratory-based approach for better understanding of wireless communication is described. Model for a practical test bench is provided and its application toward developing various laboratory-based experiments is discussed. The experiments are not only useful for better understanding of wireless communication concepts but also for research and development of the new communication technologies.

1.1 Importance of Laboratory-Based Learning of Wireless Communications

The high demand for communications anywhere, anytime and now with anything has been the driving force for the development of wireless services and technologies. These technologies have evolved significantly over the last couple of decades, from simple paging to real-time voice communication further to very high rate data communications, and recently to a wide variety of applications. This dramatic change has affected society in many aspects, enabling people and machines to communicate in ways unimaginable in the past and contributing to the quality of life that is enjoyed today.

In parallel to the development of new wireless standards, recently software defined radio (SDR) [1] and cognitive radio (CR) [2] concepts gained significant interest among wireless communication community. One of the main characteristics of CR is the adaptability where the radio parameters (including frequency, power, modulation, and bandwidth) can be changed depending on the radio environment, user's situation, network condition, geolocation, and so on. SDR can provide very flexible radio functionality by avoiding the use of application-specific fixed analog circuits and components. Therefore, SDR can be considered as the core enabling technology for cognitive radio. With this ever growing wireless communication technologies and standards along with the introduction of new concepts like CR and SDR, a strong desire to develop a flexible laboratory platform to teach wide variety of wireless techniques has emerged. Laboratory benches that are equipped with SDR capable transmitters and receivers can address this goal.

Comprehending certain subjects such as telecommunications is very challenging due to their highly abstract nature. The classical theoretical knowledge, unless accompanied by practical and interactive experience, is destined to perish since it prevents observation of the various cause and effect relationships between different aspects of a communication system. Therefore, numerical models are widely used to assist in the evaluation and visualization of such complex systems. Trainees can manipulate the system and subsystem parameters independently and grasp their individual effects using various numerical tools. These skills are especially critical in their professional career since troubleshooting problems with such tools is easier than fixing them in the hardware prototyping stage. Nonetheless, the validity of the aforementioned models is limited by the assumptions. Therefore, theoretically and numerically verified designs must also be implemented in hardware and tested under various channel conditions and realistic scenarios. The hardware implementation can be achieved practically using flexible radio platforms. It should also be pointed out that the numerical and hardware implementations provide a convenient way for trainees to design telecommunication systems by themselves and assist reinforced learning.

In this chapter, we introduce a wireless communication systems lab that will provide readers with the experience to design, test, and simulate wireless systems (along with wireless circuits) using modern instrumentation and computer-aided design (CAD) software. The described approach enhances understanding of the wireless and microwave concepts significantly and builds a bridge between concepts on radio frequency (RF) circuits/devices and wireless systems and networking. The described laboratory-based approach is developed in such a way that it can promote the understanding of other related wireless concepts at all levels: wireless systems, wireless networks, cognitive radio and SDR, digital baseband signal-processing algorithm development and hardware implementation, wireless circuits, wireless devices, and components. In addition, the lab approach can serve as a resource for several research projects for both undergraduate and graduate students. As a result, this new lab approach represents an opportunity to capture the momentum of the current wireless activity worldwide and dramatically enhance the critical area of communications systems. The relation of the lab approach with various components of wireless and microwave curriculum is shown in a very high level graph in Figure 1.1.

Figure 1.1 The relation of the lab approach with various components of wireless and microwave systems.

1.2 Model for a Practical Lab Bench

Figure 1.2 shows the laboratory bench setup along with the integration of various components and instruments. The four important elements of the model (theory, computer simulations and software, test and measurement instruments, and hardware) are shown in different rows. The top row shows the theory and concepts of various systems, subsystems, and components. Understanding the mathematics, statistical models, and the fundamental theories of wireless communication systems is extremely important. A solid design starts with a good understanding of the fundamentals. In our educational systems worldwide, most of the emphasis in teaching wireless communications is in the theory. However, the communication systems are getting more and more complex and exhibit nonlinear behavior, making it very difficult to analyze mathematically in closed form. Therefore, to help the understanding of these difficult concepts, simulations are also used. Simulations are especially important in the early design cycle as fixing mistakes is costly and time-consuming in the late stages of the wireless product development. The second row in Figure 1.2 presents the simulation world where the engineers (and students) can simulate and test various wireless communication systems (or subsystems). The simulation can help to get intuitive feeling of how theoretical knowledge is related to the real world; how to model and implement a realistic real-world wireless communication system using computer simulations; how various parameters affect the performance of the system, etc. Note that the traditional theoretical analysis and computer simulations are based on accurate modeling of the overall system, subsystems, and components.

Figure 1.2 Model used for the wireless communication systems lab.

The reliability and accuracy of the developed system and product depend on the accuracy of the assumptions and models used in the simulations and the theory. Hence, the system developers must be very careful in the assumptions and approximations they make in developing a system model. In the theoretical and simulation approaches, designs are at the algorithmic and behavioral level and hence often don't include any architectural or implementation details.

A step beyond the computer only simulation is the usage of the flexible radio hardware through a testbed. Testbed allows for further development and verification of the algorithms or ideas under real-world conditions. Additionally, testbeds provide an opportunity to employ mixed domain analysis. Especially, in developing SDR and cognitive radio system...

Table of contents

• Cover
• Table of Contents
• Title Page
• Copyright
• Preface
• List of Contributors
• Acronyms List
• 1 Hands-on Wireless Communication Experience
• 2 Performance Metrics and Measurements
• 3 Multidimensional Signal Analysis
• 4 Simulating a Communication System
• 5 RF Impairments
• 6 Digital Modulation and Pulse Shaping
• 7 OFDM Signal Analysis and Performance Evaluation
• 8 Analysis of Single-Carrier Communication Systems
• 9 Multiple Accessing, Multi-Numerology, Hybrid Waveforms
• 10 Wireless Channel and Interference
• 11 Carrier and Time Synchronization
• 12 Blind Signal Analysis
• 13 Radio Environment Monitoring
• Index
• End User License Agreement