In this paper, a novel signal
processing technique hasbeen developed to refocus moving targets image from their smeared
responses in the Synthetic Aperture Radar (SAR) image according to the
characteristics of the received signals for moving targets. Quadratic Phase Function
is introduced to the parameters estimation for moving target echo and SAR
imaging. Our method is available even under a low SNR environment and acquiring
an exact SAR image of moving targets. The simulated results demonstrated the validity of the
A domain extension algorithm to correct the comparator
offsets of pipeline analog-to-digital converters (ADCs) is presented, in which
the 1.5-bit/stage ADC quantify domain is extended from a three-domain to a five-domain.
This algorithm is designed for high speed and low comparator accuracy
application. The comparator offset correction ability is improved. This new
approach also promises significant improvements to the spurious-free
dynamic range (SFDR), the total harmonic distortion (THD), the signal-to-noise
ratio (SNR) and the minor analog and digital circuit modifications. Behavioral
simulation results are presented to demonstrate the effectiveness of the
algorithm, in which all absolute values of comparator offsets are set to |3Vref/8|. SFDR, THD and SNR are improved, from 34.62-dB, 34.63-dB and
30.33-dB to 60.23-dB, 61.14-dB and 59.35-dB, respectively, for
a 10-bit pipeline ADC.
Mathematical simulation method can be adopted to check flight characteristic of UAV, also can be adopted to simulate hardware experiments of unmanned aerial vehicle (UAV), then related flight experiments can be performed. The simulation method can reduce the flight periods, cost and risk. UAV flight model research play an important role in simulation and modeling in initialize periods of the UAV producing. The study of the paper focuses on the aerodynamic force modeling work of UAV based on Simulink. The designed model not only can afford mathematics simulation experiment but also will do benefits to the research of flight control, navigation guidance of UAV.