항공노드 중계 기반의 지역 측위 알고리즘 및 다중접속기법
Regional Positioning Algorithm and Multiple Access Scheme based on Relaying of Airborne nodes
- 주제(키워드) Regional positioning , Airborne relay , Integration of communication and navigation
- 발행기관 아주대학교
- 지도교수 임재성
- 발행년도 2017
- 학위수여년월 2017. 2
- 학위명 박사
- 학과 및 전공 일반대학원 컴퓨터공학과
- 실제URI http://www.dcollection.net/handler/ajou/000000024402
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
The global navigation satellite system (GNSS) has been used in various areas as an infrastructure to provide precise position and timing. Furthermore, according to proliferation of the location-based services and the advent of network centric warfare, sharing of the acquired situational information became important as well as estimating the physical position of persons or objects. However, the GNSS is vulnerable to intentional or unintentional interferences and is not available in shaded areas due to weak received signal strength and well-known signal structure. Since positioning and communication systems are separately configured, an extra link is needed for sharing. For these drawbacks, the alternative positioning and the integration of communication and navigation is required. This dissertation deals with the alternative positioning scheme for GNSS-less environments, and presents the design of multiple access scheme for combining the proposed positioning scheme with communication networks. We propose an independent positioning scheme: 1) airborne relay-based positioning scheme (ARPS) and design two schemes for improving the performance of ARPS: 2) Enhanced algorithm and 3) Self-correction scheme. We also integrate the ARPS into time division multiple access (TDMA) networks: 4) Networked ARPS (N-ARPS). ARPS employs the relaying of navigation signals through airborne nodes to provide positioning up to non-LOS user. The user sequentially estimates the position of airborne relays and its own position using reception and propagation times of relayed signals. Enhanced algorithm re-estimates the user position by adding a virtual pseudorange measurement of reference station to improve the ARPS vertical accuracy. To prevent performance degradation, the user calculates the expected errors for the initial and re-estimation using geometrical factor and error source information, and then compares to determine whether to re-estimate. In self-correction scheme, each reference station adjusts the transmission time of navigation signals to reduce errors in pseudorange measurements. N-ARPS uses three strategies to integrate ARPS into TDMA networks: First, consecutive slot allocation for minimizing mobility effect: Second, airborne relay selection based on the distance from a master station: Third, secondary scheme against navigation signal loss. We conduct extensive simulations to evaluate ARPS, N-ARPS, and enhanced schemes. The simulation results show that ARPS guarantees high accuracy than conventional pseudolite-based positioning scheme. Furthermore, the enhance scheme improves the accuracy of ARPS and expands service coverage. Finally, ARPS can operate in TDMA networks with relatively good performance.
more목차
1. Introduction 1
1.1 Background 1
1.2 Contributions 2
1.3 Organization 3
2. Positioning System and Theory 4
2.1 Classification of Positioning Systems 4
2.2 Positioning Techniques 6
2.2.1 Positioning method 6
2.2.2 Estimation technique 7
2.3 Accuracy measures and Error models 10
2.3.1 Accuracy measures 10
2.3.2 Measurement errors 13
3. Regional Positioning Algorithm 15
3.1 Related Works 15
3.1.1 Pseudolite-based Positioning Scheme 15
3.1.2 Chinese Area Positioning System 18
3.1.3 Differential GPS 21
3.2 ARPS: Airborne Relay-based Positioning Scheme 22
3.2.1 ARPS configuration 22
3.2.2 ARPS Positioning Algorithm 24
3.2.3 Simulation Assumptions and Construction 28
3.2.4 Performance Evaluation 31
3.3 Enhanced ARPS Algorithm 37
3.3.1 Procedures of the Enhanced Algorithm 37
3.3.2 Mathematical Expression of Positioning Procedures 39
3.3.3 Simulation Assumptions and Construction 44
3.3.4 Performance Evaluation 46
3.4 Self-correction Scheme 53
3.4.1 Procedures of Self-correction Scheme 53
3.4.2 Simulation Assumptions and construction 56
3.4.3 Performance Evaluation 58
3.5 Chapter Summary 62
4. Multiple Access Scheme 63
4.1 Related Works 63
4.1.1 Relative Navigation of JTIDS 63
4.1.2 Universal Access transceiver system 66
4.2 Feasibility Study of ARPS in UAT 69
4.2.1 Embedding ARPS into UAT 69
4.2.2 Simulation Assumptions and Construction 71
4.2.3 Performance Evaluation 73
4.3 N-ARPS: Networked-ARPS 75
4.3.1 Integrated ARPS into TDMA networks 76
4.3.2 Simulation Assumptions and Construction 83
4.3.3 Performance Evaluation 85
4.4 Chapter Summary 89
5. Conclusions 90
Appendixes 92
A.1 Derivation of Navigation Equations for an Airborne Pseudolite-Based System 92
References 95
