臺灣博碩士論文加值系統

在這篇論文中，利用雙頻接收機特性，提出一個基於ESPRIT( Estimation of Signal Parameter Via Rotational Invariance Techniques )的演算法，應用於偵測訊號來向相對於接收機的仰角與方位角。ESPRIT是一個已知的訊號系統參數估測演算法，在DOA的估測上有很多的應用。然而在傳統的ESPRIT架構下，他必須使接收機維持在一組兩個，且假設每組的距離向量已知。
為了放寬接收機物理架構上的限制，考慮一個GNSS雙頻接收機接收到一組有固定頻率差的獨立訊號，及都卜勒頻偏，可以推得一個基於ESPRIT的演算法;在假設衛星在 軸及 軸移動速度已知的情況下，可以估測出衛星仰角及方位角，藉以達成用一顆衛星來定位的目標。而假設衛星在 軸及 軸移動速度已知並不是一個非常嚴格的條件，我們可以大約的從廣播星曆去預測衛星在 軸及 軸移動速度。
最後，透過模擬實驗驗證此演算法的可用性，並探討一些可能的問題。

In this thesis, an ESPRIT-based direction-of-arrival (DOA) estimation method is proposed to estimate the azimuth and elevation angles of dual-frequency measurements coming from independent signal sources. ESPRIT (Estimation of Signal Parameter via Rotational Invariance Techniques) is a well-known algorithm for estimating DOA based on rotational invariance technique. For the traditional ESPRIT method, however, the array of sensors (usually more than four) has to be placed in a specific geometric structure. In this paper, we propose a new way to approach the similar result without imposing constraints on the array geometry by using dual frequency GNSS (Global Navigation Satellite System) receiver. In the proposed method, the DOA of GNSS signals can be estimated using only one dual frequency receiver and the physical structure limitation can be circumvented by assuming that the velocity of the satellite is known. This is generally not a very stringent requirement since the velocity of GNSS satellite can be predicted in an accurate manner using the broadcast ephemeris. Finally, some simulation results are given to verify the proposed algorithm.

誌謝 I
摘要 Ⅱ
Abstract III
Contents Ⅳ
List of figures Ⅴ
List of tables Ⅵ
Chapter 1 Introduction 1
1.1 Motivation and Literature Survey 1
1.2 Organization of the Thesis 2
Chapter 2 Basic Positioning Problem in GNSS System 3
2.1 Basic Positioning Problem Concept 3
2.2 Basic Equations for Finding User Position in GNSS System 4
2.3 Obtaining User Position from Pseudoranges 6
Chapter 3 Introduction to ESPRIT 9
3.1 Array Geometry 9
3.2 Data Model 10
3.3 ESPRIT – The Invariance Approach 11
Chapter 4 ESPRIT-based Algorithm – using Dual Frequency Receiver 13
4.1 Doppler Shift 13
4.2 DOA estimation – Two-Dimensional Case 14
4.3 Extension – Three-Dimensional Case 16
Chapter 5 Simulation Results 19
5.1 Simulations of DOA Estimation 19
5.2 Simulations of Relationship between the Estimation Error and Integer Ambiguity 14
Chapter 6 Conclusions and Future Works 29
6.1 Conclusions 29
6.2 Future Works 29
References 30

[1] R. Roy and T. Kailath, “ESPRIT-Estimation of signal parameters via rotational invariance techniques,” Opt. Eng., vol. 29, no. 4, pp. 296-313, Apr. 1990.
[2] Tsung-Hsien Liu, J. M. Mendel, “Azimuth and elevation direction finding using arbitrary array geometries,” IEEE Trans. Signal Processing, vol. 46, pp. 2061–2065, Sep. 1998.
[3] R. Challa and S. Shamsunder, “High-order subspace based algorithms for passive localization of near-field sources,” in Proc. 29th Asilomar Conf., Oct. 1995, pp. 777–781.
[4] M. C. Dogan and J. M. Mendel, “Applications of cumulants to array processing, Part I: Aperture extension and array calibration,” IEEE Trans. Signal Processing, vol. 43, pp. 1200–1216, May 1995.
[5] J. Li and R. T. Compton, Jr., “Two-dimensional Angle and Polarization Estimation using the ESPRIT Algorithm,” IEEE Trans. Antennas and Propagation, Vol. 40, pp. 550-555, May 1992.
[6] J. M. Mendel and E. Gonen, “Direction-finding using higher-order statistics,” CRASP Rep., Signal Image Process. Inst., Univ. Southern Calif., Los Angeles, CA, Aug. 1995.
[7] J. M. Mendel, “Tutorial on higher-order statistics (spectra) in signal processing and system theory: Theoretical results and some applications,” Proc. IEEE, vol. 79, pp. 278–305, Mar. 1991.
[8] R. O. Schmidt, “Multiple Emitter Location and Signal Parameter Estimation,” IEEE Trans. Antenna and Propagation, Vol. 34, No. 3, pp. 276-280, March 1986,
[9] A. Swindlehurst and T. Kailath, “Azimuth/elevation direction finding using regular array geometries,” IEEE Trans. Aerosp. Electron. Syst., vol. 29, pp. 145–156, Jan. 1993.
[10] A. Veen, P. Ober, and E. Deprettere, “Azimuth and Elevation Computation in High Resolution DOA Estimation,” IEEE Trans. Acoustic, and Speech Signal Processing, Vol. 33, pp. 1828-1832, April, 1985.
[11] K.-Y. Yu, I.Sharp, and Y. J. Guo, Ground-Based Wireless Positioning, John Wiley &; Sons, UK, 2009.
[12] J. B.-Y. Tsui, Fundamentals of GPS Receivers: A Software Approach, John Wiley &; Sons, New York, NY, USA, 2005.
[13] P. Misra and P. Enge, Global Positioning System—Signals, Measurements and Performance, 2nd ed., Lincoln, MA: Ganga-Jamuna Press, 2001.
[14] S. Haykin, Communication Systems, 4th Edition, Wiley &; Sons, 2001.