Recent advances in the Micro Electro-Mechanical System (MEMS) technology have made wireless MEMS accelerometers an attractive tool for Structural Health Monitoring (SHM) of civil engineering structures. To date, sensors' low sensitivity and accuracy--especially at very low frequencies--have imposed serious limitations for their application in monitoring large-sized structures. Conventionally, t...

A theoretical formulation characterizing the noise performance of strain estimation using envelope signals is presented for the cross-correlation based strain estimator in elastography, using a modified strain filter approach. The strain filter describes the relationship among the elastographic signal-to-noise ratio (SNRe), sensitivity, contrast-to-noise ratio and dynamic range for a given reso...

Introduction: High-power transmit-receive (T/R) switches are a core component of pulsed NMR and MRI spectrometers. The usually employed PIN diodes offer low losses and high power handling capabilities, but are inherently slow semiconductors and let switches usually transit within 5-20 μs from transmission to reception. For liquid state NMR methods, this dead-time is mostly not a big caveat, how...

In this paper, we present a RF directional modulation technique using a switched antenna array for physical layer secure communication. The main idea is that a switching scheme of the switched antenna array is designed according to a spreading sequence for the purpose of spreading spectrum of the transmit signal. The transmit signal is associated with the spreading sequence and the direction of...

Radio over Fiber (RoF) technology the integration of microwave and optical networks is a potential solution for increasing capacity and mobility as well as decreasing costs in the broadband access network. The concept of RoF means to transport information over optical fiber by modulating the light with radio frequency signal (RF) or at an intermediate frequency signal (IF) to take advantage of ...

Topics 1. Main analog components for receivers-amplifiers-filters-mixers-oscillators 2. Receiver architectures and their properties-superheterodyne principle-direct conversion-DC offsets as a challenging problem-low IF, Weaver-effects of I/Q imbalance 3. Non-idealities and performance meatrics of the analog front-end modules-sensitivity, dynamic range-noise figure-intermodulation distortion, IP...

Zero-IF receiver has some advantages, such as small factor, low cost and easily integrated on a chip. They make it competitive of RF receivers. However, DC Offset and flicker noise, etc., have profound effects in zero-IF receiver, which need not be considered in super-heterodyne receiver. Following a major study of flicker noise, possible solutions are given, especially those based on the passi...