Showing 3 results for Noise Cancellation
S. M. Dehghan, A. Yazdian, M. Mohamadian,
Volume 2, Issue 2 (4-2006)
Abstract
In this paper a hybrid active DC line conditioner for fluctuations and ripples
reduction in voltage and current of DC power systems is proposed. Malfunctions in
operation of equipments and systems which are supplied by low quality distribution power
systems are one of the main effects of DC voltage ripple. In the proposed configuration a
hybrid system including series and shunt active line conditioners for ripple reduction of
load voltage and source current is used. Simulation and experimental results are provided to
show the performance of the proposed configuration in different states.
M. Shams Esfand Abadi, S. Nikbakht,
Volume 7, Issue 2 (6-2011)
Abstract
Two-dimensional (TD) adaptive filtering is a technique that can be applied to many image, and signal processing applications. This paper extends the one-dimensional adaptive filter algorithms to TD structures and the novel TD adaptive filters are established. Based on this extension, the TD variable step-size normalized least mean squares (TD-VSS-NLMS), the TD-VSS affine projection algorithms (TD-VSS-APA), the TD set-membership NLMS (TD-SM-NLMS), the TD-SM-APA, the TD selective partial update NLMS (TD-SPU-NLMS), and the TD-SPU-APA are presented. In TD-VSS adaptive filters, the step-size changes during the adaptation which leads to improve the performance of the algorithms. In TD-SM adaptive filter algorithms, the filter coefficients are not updated at each iteration. Therefore, the computational complexity is reduced. In TD-SPU adaptive algorithms, the filter coefficients are partially updated which reduce the computational complexity. We demonstrate the good performance of the proposed algorithms thorough several simulation results in TD adaptive noise cancellation (TD-ANC) for image restoration. The results are compared with the classical TD adaptive filters such as TD-LMS, TD-NLMS, and TD-APA
R. Mirzalou, A. Nabavi, Gh. Darvish,
Volume 8, Issue 3 (9-2012)
Abstract
This paper presents a new ultra-wideband LNA which employs the complementary derivative superposition method in noise cancellation structure. A pMOS transistor in weak inversion region is employed for simultaneous second- and third-order distortion cancellation. Source-degeneration technique and two shunt inductors are added to improve the performance at high frequencies. The degeneration inductor resonates at fT/2 and realizes a new input matching technique that widens the bandwidth with decreasing its quality factor and input capacitance, while flattens the input resistance and also improves the 1dB Compression Point. The shunt inductors resonate at the center frequency of the band and improve the effective bandwidth of noise/distortion cancellation technique. This LNA has been designed in a 0.18-μm CMOS process and consumes 8.3 mA from 1.8 V power supply. The chip area is 0.55mm2. The noise figure and voltage gain are 4.48-5.18 dB and 13 dB, respectively. S11 is lower than -13.5 dB over 5.8–10.6 GHz and IIP3 is 14.5–17.5 dBm, IIP2 is 14–15.5 dBm. This technique improves IIP3 more than 9dB.