Generalization of Mixed-Mode Matrix for Analyzing Wireless Communication Based on Orbital Angular Momentum (OAM)
- 주제(키워드) Mixed-Mode Matrix , Orbital Angular Momentum
- 발행기관 아주대학교
- 지도교수 감동근
- 발행년도 2019
- 학위수여년월 2019. 2
- 학위명 박사
- 학과 및 전공 일반대학원 전자공학과
- 실제URI http://www.dcollection.net/handler/ajou/000000028575
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
This dissertation introduces a mixed-mode matrix generalization of scattering parameters which is suitable for the investigation of wireless communication based on orbital angular momentum (OAM), and antenna arrays that radiate electromagnetic fields showing OAM are being studied to provide an explanation of the generation of OAM based on fields. To this purpose a unitary transformation matrix is defined that contains as basis vectors the transmitted and received amplitudes that correspond to OAM-based communication between two antenna arrays. The mixed-mode matrix is then obtained from the corresponding similarity transformation of the standard scattering matrix available e.g. from numerical simulations or measurements. The mixed-mode matrix allows better physical insight into OAM-based communication by clearly separating all modes and is more efficient than post-processing of single-antenna results in a system simulator. Mode conversion/isolation and proper mode termination can be easily quantified. Also, it allows to generalize the interpretation of OAM-based communication by focusing on the property of a constant phase difference within each antenna array. The usefulness of this approach is demonstrated using Method of Moments (MoM) simulations of dipole radiators in various arrangements of a transmitting and a receiving array. Systematic parameter studies that reveal dependencies of OAM-based communication are possible by using the mixed-mode matrix. As an application, the communication pattern is studied to obtain the suitable position and relative orientation in free space for good mode isolation or communication.
more목차
Ⅰ. Introduction 1
1.1 Motivation 1
1.2 Contribution Review 3
1.3 Organization 4
Ⅱ. Investigation of the OAM Density in Electromagnetic Fields 5
2.1 Numerical Calculation of OAM Field Properties 6
2.1.1 Configuration of Antenna Arrays for Generating OAM Fields 7
2.1.2 Demonstration of OAM fields Based on Numerical Methods 13
2.1.3 Explanation for OAM Based on Electromagnetic Field Properties 17
2.2 Numerical Investigation of OAM Densities 21
2.2.1 Dipole Orientations 21
2.2.2 Effects on an Infinite Electrical Perfect Conducting Plane 24
2.3 Summary 30
Ⅲ. Mixed-Mode Matrix for Investigation of Wireless Communication Related to OAM 31
3.1 Communication System Configuration 32
3.2 Mixed-Mode Matrix for Investigation of Wireless Communication based on OAM 35
3.2.1 Standard Scattering Matrix of Multi-Antenna System 35
3.2.2 Transformation Matrix 38
3.2.3 Mixed-Mode Scattering Matrix 40
3.3 Mixed-Mode Matrix Validation in a Wireless Communication System 43
3.3.1 Setup and MoM Calculation 43
3.3.2 Mixed-Mode Matrix in Communication Examples 45
3.3.3 System Circuit Simulation 46
3.4 Summary 52
Ⅳ. Systematic Parameter Study of OAM 53
4.1 Systematic Parameter Study of OAM Based Communication 55
4.1.1 Communication Distance 55
4.1.2 Array Diameter 57
4.1.3 Number of Array Elements 60
4.1.4 Azimuth Angle 62
4.1.5 Rx Rotation Angle 63
4.1.6 Polar Angle 64
4.1.7 Tilt Angle 67
4.2 Relation Between OAM density and Mixed-Mode Matrix 71
4.2.1 Tilt Angle and OAM Density 71
4.3 Summary 76
Ⅴ. Conclusion 77
Abstract in Korean 85
