日本的準天頂衛星系統於2010年發射第一顆名為“Michibiki”的衛星，更於2017年夏天發射第二顆於傾斜地球同步軌道的衛星，並開始傳送L5S實驗訊號，此訊號相當於位在L5 頻段的增強訊號並提供相關定位修正量。因此，本研究的目標是開發一套設備來評估準天頂衛星系統 L5S實驗訊號在亞太地區的性能。我們使用軟件定義無線電技術實現此雛型接收機，並以此達成所有必須的訊號處理。所提出的雛型接收機由Novatel的天線，通用式軟體無線電平台和個人電腦組成。此接收機實現了需多相關訊號處理流程，包括類比數位訊號轉換，衛星訊號的擷取及追蹤。最後，我們提出幾種訊號品質分析方法來量測此訊號的強度及連續性，並分析了同時間於相同頻段收到的全球定位系統訊號量測結果進行比較。此實驗訊號於實驗期間平均強度落在40.19 dB, 而於訊號連續性部分，經由所提出的分析方法結果落在96.67%.

The new QZSS satellites launched in the summer of 2017 can transmit the L5S signal, which is identical to the L5 SBAS signal. Thus, the objective of this research is to develop a piece of equipment to assess the QZSS L5S experimental signal in the Asia Pacific region. We use a software-defined receiver (SDR)for QZSS L5S signal reception to assess all the necessary signal processing techniques. The SDR consists of a GNSS antenna, a Universal Software Radio Peripheral (USRP) platform, and a personal computer. The SDR implements all receiver chains, including the digital signal processing, performing signal acquisition, and tracking of the available satellite signals. To evaluate the performance of the QZSS L5S SDR, the acquired QZSS satellite is marked, and the value of acquired correlation peak to next peak ratio (CPPR) is calculated in the signal acquisition process. Finally, we apply several signal quality analysis (SQA) methods to analyze the L5S signal continuity and signal strength for various times. For the signal strength analysis, the averaged C/N0 value was 40.19 dB. For the signal continuity analysis, the cycle slip was observed, and several signal data were calculated for the purposes of comparison, for which the minimum value was 96.67% in the presented results.

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