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Measurements of Wearable Systems and Antennas
Published in Albert Sabban, Novel Wearable Antennas for Communication and Medical Systems, 2017
The signal generator should be stable with controlled frequency value, good spectral purity, and controlled power level. A low-cost receiving system consists of a detector and amplifiers. Several companies sell antenna measurement setups, such as Agilent, Tektronix, Antritsu, and others.
Testing Electronic Circuits
Published in Trevor Linsley, Electronic Servicing and Repairs, 2014
A signal generator is an oscillator which produces an a.c. voltage of continuously variable frequency. It is used for serious electronic testing, fault-finding and experimental work. One application for a signal generator is to test the frequency response of an audio amplifier to a range of frequency.
Design and Measurements Process of Wearable Communication, Medical and IOT Systems
Published in Albert Sabban, Wearable Systems and Antennas Technologies for 5G, IOT and Medical Systems, 2020
The signal generator should be stable with controlled frequency value, good spectral purity and controlled power level. A low cost receiving system consists of a detector and amplifiers. Several companies sell antenna measurement setups, such as Agilent, Tektronix, Anritsu and others.
Efficient analytical modeling for pulsed eddy current signals using adaptive interpolation-based Fourier transform
Published in Nondestructive Testing and Evaluation, 2023
Zhian Xue, Mengbao Fan, Binghua Cao, Bo Ye
The experimental system of PEC testing consists of a PC, signal acquisition card, signal generator and coil, as shown in Figure 11. The type of the acquisition card is NI USB-6356, which is a high-speed acquisition card transmitted through USB. This acquisition card has eight synchronous analog input channels, and the sampling frequency of each channel is 1.25 MS/s with a 16-bit resolution. NI USB-6356 has a NI-DAQmx driver and can be programmed by LabVIEW software. The product model of the signal generator is DG1022Z, the maximum output frequency is 25 MHz, the maximum sampling rate is 200 MHz, and the minimum rising/falling time of the square wave pulse is 20ns. PC and the signal acquisition card are connected by USB. The parameters of the coil and specimen in the experiment are shown in Table 1.
Laboratorial Study of the Combined Effect of SO2 and High-Temperature Ageing on the Physical and Mechanical Properties of Encostinha Marble, a Portuguese Stone
Published in International Journal of Architectural Heritage, 2023
Edite Martinho, Amélia Dionisio, Ana Sofia Angélico
The P- and S-wave travel times were measured on all specimens for each test condition in three orthogonal axis systems (A, B, C) by direct transmission and with one measurement for each direction (Figure 2). The ultrasonic equipment was composed of i) a signal generator unit (BK Precision, 401 1A 5 MHz Function Generator), operating with 20 V peak-to-peak, square wave selected and frequency around 40 Hz; ii) an oscilloscope (Rohde & Schwarz HMO 1002 Series 1GSa/s/1MB); iii) a signal amplifier and iv) two ultrasonic piezoelectric transducers (transmitter and receiver). In laboratory tests, given the difference between the travel times of the P- and S-waves, different transducers were used to measure the P- and S-wave travel times although all sensors have the shape of a thin disk. For the P-wave, PXRw piezoelectric transducers manufactured by PengXiang Technology Co., Ltd were used, with a flat frequency response range of 80 kHz–400 kHz and a contact surface with a 16 mm diameter. To measure the S-wave travel times, the transducers were horizontally polarised transducers (Physical Acoustics, model SW37) with a resonance frequency of 300 kHz and a contact surface of 11 mm. Travel time uncertainties were considered ±0.2 μs for the P-wave travel time and ±0.4 μs for the S-wave travel time. To ensure good contact between the transducers and the stone specimens, a visco-elastic couplant was used.
Determining dielectric properties of nematic liquid crystals at microwave frequencies using inverted microstrip lines
Published in Liquid Crystals, 2022
Haofeng Peng, Yongwei Zhang, Senlai Zhu, Murat Temiz, Ahmed El-Makadema
The IMSL device was fabricated using a standard photolithography process. For Design 1, the fabrication process was based on the substrate of commercially available Rogers Duroid. Both the top and middle layers, fabricated from RO4350B, have a thickness of 0.254 mm (as shown in Figure 5, a = 0.254 mm for Substrate 1, b = 0.254 mm for Substrate 2) and an effective dielectric constant of = 3.66. Moreover, a uniform surface of approximately 100 nm was deposited by spin coating PI on the bottom surface of Substrate 1, and the microgrooves were created by rubbing unidirectionally along the short edge direction of the substrate. The ground plane was fabricated from a 30 mm 20 mm 1 mm slab of copper sheet and was dealt with in the same deposition and rubbing processes. In the measurement, the frequency response of LC samples was measured using VNA (Keysight N9918A) with the function waveform signal generator to provide 1 KHz sine wave signal as a voltage source. The material used for the substrate of Design 2 is F4BMX. Design 2 has the same thickness of each layer as Design 1. In Design 2, the dielectric permittivity of the top layer is = 2.2, while the middle layer has an effective dielectric constant of = 3.