The small scale artifacts generated by aliasing noise existing everywhere in an image,bring difficulties to some applications,such as target identification.

Minifying digital images used downsampling introduces aliasing noise.

Assuming several sets of system design parameters we analyze aliasing noise that exists in sampled-imaging system widely, blurring effects of optical imaging system and the tradeoff between them by the way of computer simulation.

Uniform undersampling technique of bandpass signal and its engineering application in software digital IF receiver;

Project of Convex Set Method for Reconstructing A Super-resolution Image from Multiframe Undersampling Images;

Application of bandpass undersampling principle in software radio;

Time-delay estimation for sub-sampling sinusoidal signals;

In order to break through the limitation of Electronic analog-to-digital converter in speed and time-delay precision,a wideband digital frequency measurement method based on optical sub-sampling is proposed.

In the algorithm for estimation of frequency of ultra-wideband LFM signal based on multi-channel and sub-sampling,even tiny error of the remainder can lead to huge error of the frequency.

According to the characteristics of the wayside frequency-shift signal spectrum,and based on a great number of computer emulators and real-time experiments and on non-complete periods sampling,the feasibility of applying the under-sampling technology to the real-time FFT analytical method of tramroad FSK signal is validated.

Based on the theoretic modeling and analysis of the IF GPS signals,an accurate software simulator of IF GPS signals is implemented in Matlab/Simulink,the effects of noise,under-sampling and receiver clock error are also simulated.

The theoretical analysis has proved that in the condition of under-sampling, because the paired echoes will be appeared, the system’s multi-object resolution will be affected.

Using Different Frequencies Method to Solve Bandpass sub-nyquist sampling;

In view of the present sub-Nyquist sampling frequency estimation method,in order to overcome the existing problems such as complex arithmetic and difficult to engineer realizing,the paper puts forward a three-sample rates switching frequency estimation method based in virtual instruments.

Based on an auxiliary time-delay channel and ESPRIT approach,a new algorithm for wide band frequency estimation with sub-Nyquist sampling was proposed.

An algorithm for estimation of wideband LFM signal parameters based on subsampling;

A receiver architecture is presented that utilizes the subsampling concept to down-convert the IF signal to a lower IF before been digitized.

Firstly,the paper briefly presented the imaging system’s aliasing effect as a result of subsampling and the theory of reducing aliasing effect by increasing sampling frequency.