S. K. Hampel

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This article presents the design of a fully integrated inductorless LNA for wireless applications including WLAN, Bluetooth and UWB. The circuit was fabricated in 65nm CMOS technology and operates at a supply voltage of 1.2 V. The two-stage design is comprised of a current reuse shunt feedback input stage followed by a differential pair, incorporating an(More)
This paper presents the design and implementation of a low-voltage down-conversion mixer in 65nm CMOS technology for UWB applications. The folded circuit topology with AC-coupled inverter based RF transconductance stage operates under low voltage conditions of 1.2 V with a peak gain of 14.5 dB and a 3-dB-bandwidth from 1 GHz to 10.5 GHz with 1 dBm LO power.(More)
This paper presents fully differential up-and down-conversion mixers manufactured in a triple well 45 nm standard CMOS process for low voltage UWB TX and RX applications. The proposed circuits both employ the transistor bulk terminal for signal injection. While the RX mixer uses the bulk for switching via threshold voltage modulation, the TX mixer applies(More)
This paper examines the differences occuring between virtual and true differential probing of active balanced devices in large signal region. The analysis is carried out by means of gain compression of single stage pseudo and true differential amplifiers. Based on analytical derivations, a simulation model for these amplifiers is developed and verified by(More)
This paper presents the design of a fully integrated inductorless wideband RF front-end for wireless applications including WLAN, Bluetooth and UWB. The core of the circuit is comprised of a two stage LNA, followed by a standard Gilbert cell mixer and an output buffer for measurement purposes. The chip was fabricated in 65nm standard CMOS process. The RX(More)
This article highlights the effects of a finite basic High-Impedance Surface (HIS) structure on the impedance, the directivity and the radiation pattern of a printed linear dipole antenna. Furthermore the tradeoff between the minimum and maximum needed physical size of the reflecting surface will be addressed, which has not been done in published articles(More)
This work presents the design, implementation and measurement results of a novel, gyrator-based active inductor circuit in a 1.2 V 65nm CMOS technology. By solely employing stacked nMOS-pMOS transistor combinations, the proposed differential gyrator achieves a maximal self-resonance frequency of approximately 18 GHz and features high linearity with a(More)
This work presents the design of an inductorless, monolithically integrated differential CMOS wideband amplifier covering the frequency range from 0.2 to 10.2 GHz, thus being a suitable candidate for full-band Ultra-Wideband transmitter applications. The amplifier is processed in a 1.2 V 65nm CMOS technology and is comprised of two pseudo differential(More)
This paper deals with the influence of artificial magnetic conductors (AMC), so called Sievenpiper high impedance surfaces (HIS), on the MIMO and diversity performance of a planar linear-polarized 2 times 2 dipole array at 2.45 GHz. By means of full-wave electromagnetic analysis (ANSOFTF HFSS) as well as a statistical channel model implementation the(More)
This paper examines the influence of so called Sievenpiper High Impedance Surfaces (HIS) on the diversity performance of planar dual linear-polarized cross-dipole antennas in the ISM-band at 5.5 GHz. Starting from uncoupled free-space considerations we investigate characteristic performance criteria such as Mean Effective Gain (MEG), power imbalance,(More)
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