光達是一種用於測量物體距離的技術，通過發射雷射光至目標物並計算雷射光的飛行時間，可以估計出與目標物之間的距離。近年來在自動駕駛、擴增/虛擬實境等等領域的發展使得光達越來越受到重視。混沌光是一種類似噪聲的訊號，有著亂數的特性，因此使用混沌光作為光源的混沌光達系統能提供穩定與高精準度的深度偵測結果。雖然混沌光達系統有優異的精準度及不易受到干擾的特性，但它同時具有幾個缺點，導致其應用場景受到限制: (1) 混沌光達掃描的深度點在空間上較為分散 (2) 偵測一個像素的深度點所需的時間較長。為了克服上述問題，本文提出了一種可以同時提高混沌光達系統空間解析度和時間解析度的方法。在提升空間解析度上，使用雙通道多輸入多輸出的作法並設計了相應的控制流程以同時得到兩倍的深度偵測結果。在提升時間解析度上，設計了飛行時間測距的電路以加速深度偵測的過程。實驗結果說明了使用本文所提出的方法，混沌光達系統可以同時掃描兩個通道，取得兩倍的深度圖，每個通道可以達到每秒33萬像素的吞吐量，雙通道的多輸入多輸出系統可以達到每秒66萬像素的吞吐量。

LiDAR technology can estimate the distances of environmental objects by emitting a laser and measuring the time of flight. Recent developments in the field like autonomous cars and AR/VR have led to considerable growing interests in LiDAR systems. With the random nature of chaos laser, it has been shown that using chaos laser as the light source of LiDAR can provide robust and high-accuracy depth-sensing results. Despite its outstanding precision and capability of anti-interference, the chaos LiDAR system suffers from several major drawbacks: (1) the depth points sensed by LiDAR are usually too sparse and (2) the speed of estimating depths of pixels is not fast enough for real-time processing. These drawbacks limit the usage scenario of the chaos LiDAR system. To overcome these drawbacks, this research proposed a method that can enhance both spatial and temporal resolution at a specific time. A two-channel multi-input multi-output (MIMO) scheme and the corresponding control flow were designed to acquire a double amount of depth-sensing results, and a time-of-flight (TOF) hardware was designed to accelerate the depth-sensing process. The experimental results demonstrate that the proposed techniques for the chaos LiDAR system can capture two depth maps by two scanning channels simultaneously, and each channel achieved a throughput of 330 K pixels per second, therefore the whole MIMO chaos LiDAR system achieved a throughput of 660 K pixels per second.

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