This paper presents a simple test bench providing RF vector measurements of typical wireless communication system building blocks under realistic signal conditions. The instruments are synchronized by use of an experimental method based on an estimate of the signal path’s time delay. As an example, a complex digitally modulated signal with a carrier frequency of 2.45 GHz was used. The ultimate ...

Absrract---Modulated backscatter is a RF transmission technique useful for short-range, low-data-rate applications constrained to have extremely low power requirements, such as electronic shelf tags, RF tags, and some sensor applications. The small-scale fading observed on the backscattered signal has deeper fades than a signal from a traditional one-way link of the same range in the same envir...

In this article, a novel concept is introduced to improve the radio frequency (RF) linearity of partially-depleted (PD) silicon-on-insulator (SOI) MOSFET circuits. The transition due to the non-zero body resistance (RBody) in output conductance of PD SOI devices leads to linearity degradation. A relation for RBody is defined to eliminate the transition and a method to obtain transition-free c...

In this paper, the design of a wideband RF signal generator for demodulator/receiver testing is presented. The design of test generator is based on direct digital synthesizer (DDS) and voltage-controlled oscillator (VCO), controlled by microprocessor. It provides generation of arbitrary waveform signal up to 4.5 GHz. Output signal level is adjustable with precision of 0.5 dB. Dynamic range of R...

Substrate noise generated by digital circuits on mixed-signal ICs can disturb the sensitiveanalog/RF circuits, such as Low Noise Amplifier (LNA), sharing the same substrate. This paperinvestigates the adverse impact of the substrate noise on a high frequency cascode LNA laid out on alightly doped substrate. By studying the major noise coupling mechanisms, a new and efficientmodeling method is p...

The signal evolution behaviors and corresponding image appearances for different methods of spoiling or refocusing the transverse magnetization in short TR gradient-echo imaging during the approach to steady state were investigated experimentally and using computer simulations based on the Bloch equations. Specifically, ideally spoiled, gradient-spoiled, gradient-refocused, and RF-spoiled pulse...

Riboflavin (vitamin B2, RF) is taken up in eukaryotic cells via specialized transport mechanisms. Although RF has fluorescence properties, direct microscopic visualization of RF uptake and trafficking has been complicated by cellular autofluorescence. We describe the synthesis, cellular uptake characteristics, and spectroscopic properties of a novel rhodamine-riboflavin conjugate (RD-RF), inclu...

In the near future, RF front-ends of GNSS receivers may become very complicated when multifrequency signals are available from at least four global navigation systems. Based on the direct RF sampling technique, fully digitized receiver front-ends may solve the problem. In this paper, a direct digitization RF front-end scheme is presented. At first, a simplified sampling rate selection method is...

In this work we tested viability, proliferation, and vulnerability of neural cells, after continuous radiofrequency (RF) electromagnetic fields exposure (global system for mobile telecommunications (GSM) modulated 900 MHz signal at a specific absorption rate (SAR) of 1 W/kg and maximum duration 144 h) generated by transverse electromagnetic cells. We used two cellular systems, SN56 cholinergic ...