A Low Power CMOS Imager Based on Distributed Compressed Sensing

In this work, a low power CMOS imager based on distributed compressed sensing (DCS) is proposed. DCS enables simultaneous multi-channel signal acquisition at sub-Nyquist rates, thereby saving power and hardware complexity. Multiple images are being sensed at sub-Nyquist rates with a pseudo random sequence in the analog domain and the images are recovered simultaneously with the DCS simultaneous orthogonal matching pursuit (DCS-SOMP) algorithm. The complete system has been implemented in a 1.8 V, 0.18 μm CMOS technology with a single multiplexed ADC and is capable of sensing 16 image channels simultaneously. The sensing operation has been realized in the charge domain using switched capacitor techniques and thus consuming very low power. The system performance has been tested with a set of endoscopic images and the results show an average PSNR of 29.17 dB while sensing 16 images at a compression ratio of 1/4 and at 20 frames per second (FPS) with a power consumption of 36.8 mW per image.