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1

Design of low power analog front-end for 13.56MHz RFID transponder

Saleh S., Osman M., Hamdy G., Zaki A., Elsemary H.

International Journal of Microelectronics and Computer Science

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2017

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Vol. 8, nr 4

146--149

EN

This paper presents the design of 13.56MHz RF Front-end circuit for low-power medical applications. It converts RF power into DC and then extracts the clock and the data. The design includes rectifier, voltage multiplier, voltage regulator, data demodulator, ring oscillator, RF voltage limiter and LC matching network. It provides an excellent trade-off between high performance, simplicity of architecture, and low power consumption. It is designed to be fully integrated on chip. Simulation is done using 0.35-μm CMOS technology and the results are compared with other reported RFID systems. The total power consumption is adjusted to be around 4 μW at the minimum input power.

2

Design of high-performance PFD-CP for 403MHz CMOS fractional-N frequency synthesizer

Saleh S., Hamdy G., Elsemary H., Zaki A.

International Journal of Microelectronics and Computer Science

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2017

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Vol. 8, nr 3

97--100

EN

This brief discusses the challenges and employs a novel charge-pump and a PFD/CP linearization technique to improve the performance of a 403MHz fractional-N PLL. Techniques are proposed to improve the linearity of the PLL by forcing the PFD/CP to operate in a linear part of its transfer characteristics, while the charge-pump minimizes the current mismatch between the up and down currents by using feedback. The circuit is designed in 0.13jim CMOS process and consumes a total power of 2.6mW. The simulation results show that the synthesizer has a phase noise of-128dBc/Hz at 1MHz offset.

3

A comparative study of super-regenerative receivers for BAN applications

Saleh S., Hamdy G.

International Journal of Microelectronics and Computer Science

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2017

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Vol. 8, nr 4

133--138

EN

Super-regenerative receivers have regained attention due to their unique properties making them suitable candidates for applications necessitating simplicity and ultra-low power consumption such as Body Area Networks (BAN) targeting medical devices and near body entertainment devices. In this paper, several super-regenerative receivers are proposed showing the flexibility and the ability to accommodate proper demodulation of on-off-keying (OOK) and Multi-level (M-ary) PSK modulated signal with a very limited power budget. Circuit implementation and simulation results are shown.

4

Contribution of satellite altimetry data in the geophysical investigation of the Red Sea region, Egypt

Zahran K., Saleh S.

Acta Geophysica

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2006

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Vol. 54, no. 3

303-318

EN

Successful development of geodetic satellite missions has aroused new inter-est in determining global and regional gravity field based on satellite data. Satellite altimetry data enable direct determination of the geoid over sea regions. In Egypt, where land and marine geophysical data are inadequate because of rough topography and economic reasons, the use of satellite altimetry data is of special importance. The northern Red Sea region has been selected as a site for case study of the current research, after applying spectral analysis to reveal near-surface structure, the residual geoid of the studied region shows a good correlation with the known geo-logic features. Moreover, satellite-based gravity data enhance small-scale features and agrees well with land and marine gravity data. Thus, geoid undulation and sat-ellite gravity data can be a complementary source of data to determine near-surface and deep structures.

5

Preliminary kinematic model for the Gulf of Suez, Egypt, using geodetic and seismic observations

Saleh S., Hamdy A.M., Tealeb A.

Acta Geophysica Polonica

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2005

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Vol. 53, nr 1

87-102

EN

The Suez Rift has been re-evaluated from recent three GPS measurements and earthquake data analysis. The GPS analysis reveals local principal strains along the southern part taking a NE-SW contraction. However, it takes a NNE-SSW direction in the northern part with tensile principal strains. Throughout the central part of the gulf, the principal strains tend to be in the ENE-WSW direction due to right lateral movement. The Gulf of Suez can be divided into three seismic provinces. Generally, earthquake activity markedly increases from north to south. Slip vector analyses were carried out for 23 available earthquake focal mechanisms along the Gulf of Suez. In the southern part, the slip vector is generally trending ENE-WSW and NE-SW. However, in the northern part the direction of the slip vector varies from NNE-SSW to NE-SW. The central region represents a seismic gap between the northern and southern provinces with slip vectors of a NE-SW trend. Contrary to the previous tectonic studies, compressional field has been detected from GPS analysis and focal mechanism solutions of a few earthquakes. This raises from the highly complicated motion of Sinai subplate relative to African plate to the postseismic viscoelastic relaxation of the ductile shallow layers after the occurrence of November 1995 earthquake.