A High-Multi Target Resolution Focal Plane Array-Based Laser Detection and Ranging Sensor

Area of Science:

• Optoelectronics
• Integrated Circuit Design
• Photonics

Background:

• Focal Plane Array (FPA)-based Laser Detection and Ranging (LADAR) systems face limitations in multi-target resolution (MTR).
• Conventional LADAR receivers often have underutilized readout periods.
• Enhancing MTR is crucial for advanced sensing applications.

Purpose of the Study:

• To introduce a novel digital-assisted multiple echo detection scheme for FPA-based LADAR receivers.
• To improve the MTR of LADAR systems without compromising power or area.
• To leverage existing hardware components for enhanced performance.

Main Methods:

• Utilizing the waste time in the serial data readout period of FPA-based LADAR receivers.
• Integrating an external digital signal processor (DSP) and additional analog memory.
• Developing a prototype chip in a 0.18-μm CMOS process with an 8x8 FPA configuration.

Main Results:

• Achieved a three-times enhancement in MTR compared to conventional FPA-based LADAR.
• Demonstrated a single receiver with an MTR of 20 ns.
• Reported low power consumption (7.47 mW) and small pixel area (100 μm × 100 μm).
• Characterized performance metrics including input-referred noise current (4.48 pA/√Hz), bandwidth (530 MHz), MDS (340 nA), walk error (2.2 ns), and non-linearity (0.05%).

Conclusions:

• The digital-assisted multiple echo detection scheme effectively enhances MTR in FPA-based LADAR.
• The proposed method offers a low-power, compact solution for improved multi-target detection.
• This technique has significant implications for advanced LADAR applications requiring high resolution.