本論文提出對未知跳頻參數(跳頻頻率、時間等)之跳頻訊源來向角估測方法。
本論文之來向角估測方法大致可分為兩個階段，分別為頻率跳頻訊號偵測以及訊號來向角估測。首先以低複雜度之短時距傅立葉轉換方法進行時頻分析偵測跳頻訊號，再利用得到的跳頻參數以虛擬都卜勒快速定向方法進行訊號來向角估測。
本論文以MATLAB Simulink軟體產生藍牙調變訊號作為訊號源進行模擬，針對藍牙調變訊號對於來向角估測的影響進行探討，以驗證此來向角估測方法之效能。除了理論推導及模擬分析，本論文使用三支偶極天線組成均勻圓形陣列天線，於美商國家儀器公司所開發之軟體定義無線電平台─向量收發器完成虛擬都卜勒定向儀，並於微波暗室完成跳頻訊號之訊號源定向量測實驗。量測數據分析顯示，此定向儀能成功估測跳頻訊源來向。
此外，於實際量測中，陣列天線間的互感耦合所引起的非完美的陣列響應會大幅降低估測效能。因此，本文提出及實現基於查表法的頻率─空間陣列校正法可適用於虛擬都卜勒定向儀中，有效地抑制因互感耦合影響所造成的估測誤差。

In the thesis, we propose a blind direction of arrival estimation of a frequency hopping signal without a priori information of its hopping time and frequency parameters.
The DOA estimation method can be divided into two stages, including frequency hopping signal detection and DOA estimation. First of all, we use time-frequency analysis, a low complexity short-time Fourier transform, to detect the parameters of a frequency hopping signal, and then apply the estimated hopping parameters to a quick pseudo-Doppler direction finder to perform DOA estimation.
We use a simulated Bluetooth modulated signal generated by MATLAB Simulink software to verify the performance of DOA estimation, and discuss the DOA estimation error caused by the modulation factor. In addition to theoretical derivation and numerical analysis, we implement a pseudo-Doppler direction finder using a software defined radio platform — Vector Signal Transceiver of National Instruments with a uniform circular antenna array composed by three dipole antenna elements. We have also carried out an experiment of frequency hopping signal direction finding in a microwave chamber. The measurement result shows that the direction finder can successfully detect the direction of frequency hopping signal source.
In practical, antenna mutual coupling effect can severely degrade the performance of DOA estimation. As a result, a frequency – space array calibration procedure based on a lookup table of pseudo-Doppler direction finder is presented and implemented which can effectively suppress the estimation error due to the mutual coupling effect.

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