List of Symbols 12.1 Concepts, Definitions, and Measures of Stabilitv 12.1 .l Relationship between the Power Spectrum and the Phase Spectrum 12.1.2 The IEEE Recommended Measures of Frequency Stability 12.1.3 The Concepts of the Frequency Domain and the Time Domain 12.1.4 Translation between the Spectral Density of Frequency and the Allan Variance 12.15 The Modified Allan Variance 12.1.6 Determi...

Low frequency vibration occurs especially in ground transportation, either as a cause in adjacent environment or within the vehicle itself. The piezoelectric accelerometers commonly used for vibration measurement are not suitable, hence other sensors capable of measuring accelerations down to sub-hertz region have to be used. Based on some previous experience with MEMS acceleration sensors a th...

Step-Frequency RCS measurement system is a new and remarkable RCS measurement system, which can obtain the response of target at each frequency point in an anecho chamber. Comparing it with traditional way of CW RCS measurement, more information gains in the new system. IFFT, zero insertion and the use of additional windows are some of familiar DSP techniques, which can improve the results if t...

Many animal vocalizations are non-periodic, frequency-modulated signals. Because this type of signal varies simultaneously in two dimensions, time and frequency, spectrographic measurement is constrained by the "uncertainty principle": to increase accuracy of measurement in one dimension we must sacrifice accuracy of measurement in the other dimension. Although this trade-off is unavoidable, in...

In this paper excitation characteristics of the Liquid Crystal (LC) capacitive chemical and biological sensor are examined and the optimum frequency and voltage range for the sensor interface are introduced. Interdigitated capacitor has been used for the sensor capacitance measurement and two different molecular orientations, homeotropic and homogenous, have been considered. The LC sensor capac...

Frequency discriminators are widely used in electronic warfare systems for the instantaneous frequency measurement of intercepted signals, allowing rapid identification of threat emitters. This paper reviews microwave discriminator architectures based on multiple delay line, phase measurement with parallel digital processing, for operation over decade bandwidths. An alternative reflection mode ...

Instantaneous Frequency Measurement (IFM) devices are the essential parts of anyESM, ELINT, and RWR receiver. Analog IFMs have been used for several decades. However, thesedevices are bulky, complex and expensive. Nowadays, there is a great interest in developing a wideband, high dynamic range, and accurate Digital IFMs. One Digital IFM that has suitably reached allthese requirements is mono-bi...