In this design, the upper computer and the lower computer are realized through Arduino, ZigBee, DHT11, MQ135 and PM2.5. The lower computer collects the current environment data in real time and transmits it to the upper computer through ZigBee, and the upper computer displays it in real time through PC. After testing, the system runs stably and has high precision
Large amounts of high-definition SAR image data obtained by Nyquist sampling is not conducive to signal processing and transmission. Compressive Sensing algorithm adopted has effectively improved the performance of SAR imaging. Optimization for smoothed norm reconstruction (SL0) algorithm has been implemented in the paper, due to its poor norm estimation accuracy and slow convergence speed. While an approximate hyperbolic tangent function is applied to approximate norm in sparse signal reconstruction, Substitution of revised Newton direction for traditional steepest descent direction in the iteration path is adopted to accelerate convergence rate. Wavelet transform is adopted to make sparse sampling of SAR images, and measurement matrix is designed to do image compression. Then, image constructions by OPM, SP, GPRS, SL0, and optimized SL0 have been implemented. Experimental results show that optimized SL0 algorithm has the advantages of such performance Indicators as visual effects, peak signal noise ratio (PSNR) and reconstruction error over other ones.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.