This is the first paper to present such a digital redesign method for the (conventional) OKID system and apply this novel technique for nonlinear system identification. First, the Observer/Kalman filter Identification (OKID) method is used to obtain the lower-order state-space model for a stochastic chaos system. Then, a digital redesign approach with the high-gain property is applied to improv...

The evolution from the second generation of mobile communication technology (GSM) to the third generation (UMTS) requires a change of the modulation format. Due to the fact, that in UMTS the information is also packed into the envelope of the transmission signal, a linear amplification without distortions becomes essential. Power amplifiers operate at saturation with the highest efficiency. The...

Several nonlinear adaptive techniques have been proposed for modelling nonlinear channels with memory. These techniques include Volterra series, wavelet networks, neural networks, etc. See [11, 6] for a review. For example, adaptive Volterra series have been applied in [1] for modelling digital satellite channels. These Volterra models do not characterize each element of the channel. They provi...

The frequency-response masking approach for highspeed recursive infinite-impulse response (IIR) digital filters is introduced. In this approach, the overall filter consists of a periodic model filter, its power-complementary periodic filter, and two masking filters. The model filters are composed of two all-pass filters in parallel, whereas the masking filters are linear-phase finite-impulse re...

Digital filter is mathematical algorithm that operates on discrete time signals. Different optimization algorithms can be utilized to determine the impulse response of coefficient of such a filter. Optimization problems for the design of digital filters are often complex, highly nonlinear, and multimodal in nature. The problems usually exhibit many local minima. Ideally, the optimization method...

periodic noises are unwished and spurious signals that create repetitive pattern on images and decreased the visual quality. firstly, this paper investigates various methods for reducing the effects of the periodic noise in digital images. then an adaptive optimum notch filter is proposed. in the proposed method, the regions of noise frequencies are determined by analyzing the spectral of noisy...

In the Transmission of images over channels, Images are corrupted by salt and pepper noise, due to faulty communications. Salt and Pepper noise is also referred to as Impulse noise. The objective of filtering is to remove the impulses so that the noise free image is fully recovered with minimum signal distortion. The best-known and most widely used nonlinear digital filters, based on order stat...

Digital compensation of nonlinear distortion due to nonlinear characteristic of electronic or electromechanical device is becoming more and more important. This paper considers Direct Learning Architectures (DLAs) for predistortion of nonlinear systems described using Volterra series. The adaptive predistorter which is connected in tandem with the nonlinear system can be modeled as a Volterra f...