The ratio of the depth of the index finger at the base of tbe nail (DPD) divided by the depth at the d i i interphalangeal joint (IPD) has been reported useful in evaluating subjects for the presence of digital clubbing. A ratio which exceeds 1 has been considered abnormal. This relationship was independent of age and sex. To determine whether the ratio of DPD/IPD was independent of race, measu...

Introduction: Power amplifiers (PAs) with high power efficiency are inherently nonlinear (NL). The requirements on linearity have increased since wideband signals with high peak-to-average ratios are used more in, e.g. mobile systems. Linearisation is, thus, necessary for high power efficiency of PAs. Digital predistortion (DPD) has attracted much interest since it is a cost-effective linearisa...

Digital predistortion (DPD) is used to compensate for the distortion of power amplifiers (PAs). Inspired by physical structure PA circuit, a feedback in DPD model favored. In this letter, we proposed an infinite impulse response (IIR) modeling and linearization, modifying generalized memory polynomial (GMP) model. We also propose iterative identification algorithm estimate IIR-DPD coefficients....

In this article, we propose a novel technique of digital predistortion (DPD) for dual-band power amplifiers (PAs) based on the periodically nonuniform sampling (PNS) theory. contrast to conventional DPD (2-D-DPD) models, proposed sampled (PNS-DPD) has only single input, which can largely reduce model complexity. We fold two stimuli with aliasing and feed them simple single-band model. The desir...

Digital predistortion (DPD) based on Volterra models is commonly employed to counteract the nonlinear distortion of power amplifiers. However, when concurrent dual-band signals are transmitted, 2-D DPD required. In this work, upgrading a standard model proposed and justified using multinomial theorem. The linearization performance current proposal has been compared unextended model. Fifth gener...

In this paper, a complete design procedure, together with robust system validation approaches, is presented for implementing a high-performance re-configurable digital predistortion (DPD) test platform for compensating for nonlinear distortion and memory effects induced by radio frequency (RF) power amplifiers (PAs) in the transmitters of modern wireless communication systems. This hardware and...

This paper presents and discusses two possible real-time digital predistortion (DPD) architectures suitable for envelope tracking (ET) power amplifiers (PAs) oriented at a final computationally efficient implementation in a field programmable gate array (FPGA) device. In ET systems, by using a shaping function is possible to modulate the supply voltage according to different criteria. One possi...

To compare the advantages and disadvantages of a "Natural User Interface" (see Rauterberg & Steiger 1996) a field study was carried out. During five days of the largest computer fair in Switzerland four different computer stations with (1) a command language, (2) a mouse, (3) a touch screen, and (4) a Digital Playing Desk (DPD) interface was presented for public use. In this version of the DPD ...

To compare the advantages and disadvantages of a Natural User Interface [1] a field study was carried out. During five days of the largest computer fair in Switzerland four different computer stations with (1) a command language, (2) a mouse, (3) a touch screen, and (4) a Digital Playing Desk (DPD) interface was presented for public use. In this version of the DPD the user has to play a board g...

With the advent of spectrally efficient wireless communication systems employing modulation schemes with varying amplitude of the communication signal, linearization techniques for nonlinear microwave power amplifiers (PAs) have gained significant interest. In this article, a low complexity, direct-learning multilevel lookup table based adaptive digital predistortion technique has been proposed...