Software defined radio (SDR) is a radio in which the properties of carrier frequency, signal bandwidth, modulation, and several other characteristics are defined by software. Today's SDR is turning the hardware problems into software problems, some or all of the physical layer functions are software defined. Digital down conversion (DDC) and Digital up conversion (DUC) is one of the core techno...

Abstract—This paper presents the design of a third-order Σ∆ modulator targeted for WCDMA applications. The architecture uses two operational amplifiers and distributed fully digital feed-forward paths to minimize the output swing of op-amps. Simulation results show that first and second integrator output swings are reduced by 88% and 75%, respectively. Post-layout simulation results of the modu...

The principle object of this paper is to offer a modified design of Rogowski coil based on its frequency response. The improvement of the integrator circuit for nullifying the phase difference between the waveforms of the measured-current and the corresponding terminal voltage is a further object of this investigation. This paper addresses an accurate, yet more efficient measuring and protect...

A 2-GHz direct digital frequency synthesizer (DDFS) chip-set is presented which operates at a very low supply voltage of 2 V. The chip-set consists of a CMOS DDFS-large scale integrator (LSI) which synthesizes a sine wave at 55 Msps with an internal 10-b digital-to-analog converter (DAC) and Si-bipolar image-reject up-converters. To achieve both high purity and low power dissipation, we develop...