New implementation of time domain measurement of quality factor

Author(s):  
Ming Zhang ◽  
Nicolas Llaser ◽  
Xusheng Wang ◽  
Francis Rodes ◽  
Romain Denieport
Keyword(s):  
2019 ◽  
Vol 69 (5) ◽  
pp. 427-430
Author(s):  
Deepshikha Gururani ◽  
Harish S. Rawat ◽  
Satya K. Dubey ◽  
V.N. Ojha

With the increased use of wireless communication in recent years, the use of reverberation chamber (RC) has increased to a great extent. Reverberation chambers have been eminently used for EMC testing and shielding effectiveness. The environment it provides is very similar to the reverberant surroundings that antenna undergoes in real life use. An experiment to measure total radiated power of antenna, antenna efficiency and quality factor of chamber in indoor environment is proposed. This will make the measurement very simple and inexpensive as designing and calibration of chamber will not be needed. In this paper, we have used three different techniques to compare total radiated power, quality factor, Rician K factor and efficiency of a patch antenna measured in indoor environment with RC data. The three method used include plate stirring method and two time domain methods. The time domain methods use modulated pulse and Gaussian pulse respectively for the measurement. The antenna and chamber parameters are measured in the real time and the data matched well with the RC data for different techniques.


2014 ◽  
Vol 21 (4) ◽  
pp. 825-829 ◽  
Author(s):  
Yuzhao Wang ◽  
Yong Xie ◽  
Tianlei Zhang ◽  
Guoqiang Wu ◽  
Gang Wang ◽  
...  

2016 ◽  
Vol 25 (08) ◽  
pp. 1650087
Author(s):  
Xiaojiao Ren ◽  
Ming Zhang ◽  
Nicolas Llaser ◽  
Yiqi Zhuang

Based on time-domain quality factor (Q-factor) measurement principle, we have proposed an architecture which has the potential to be integrated on-chip. Thanks to the proposed original reconfigurable structure, the main measurement error from the offset of the operational transconductance amplifier (OTA) used can be cancelled automatically during the measurement operation, leading to a high accuracy Q-factor measurement. The digital control circuit plays an important role in the automatic passage between the two configurations designed, i.e., peak detector and comparator. The main advantages of the proposed time-domain Q-factor measurement lay on the possibility of being integrated next to the Micro Electro Mechanical System (MEMS) resonator to be measured, the miniaturization of the whole measuring system as well as the enhancement of the measurement performance, and to guide the design of such architecture, a theoretical analysis linking the required accuracy and the given Q-factor to the circuit parameters have been given in this paper. The proposed circuit is designed and simulated in a 0.35[Formula: see text][Formula: see text]m Complementary Metal Oxide Semiconductors (CMOS) technology. The post-layout simulation results show that the operating frequency can reach up to 200[Formula: see text]kHz with an accuracy of 0.4%.


2014 ◽  
Vol 609-610 ◽  
pp. 1131-1137
Author(s):  
Ling Yun Wang ◽  
Xiao Hui Du ◽  
Yuan Zhe Su ◽  
Jie He ◽  
Yi Pan Li ◽  
...  

To reduce the measurement cost and time, a time domain measurement method of quality factor for MEMS resonator is presented in this paper. The relation curve between quality factor and vacuum level is obtained. The results indicate that measurement error is larger under high vacuum level when the sampling frequency is lower. The reason causing the error is analyzed and measurement precision is improved by increasing the sampling frequency. The measurement results indicate time domain measurement is advisable and improvable for MEMS resonator measurement.


Author(s):  
Miloslav Capek ◽  
Lukas Jelinek ◽  
Guy A. E. Vandenbosch

This paper deals with the old yet unsolved problem of defining and evaluating the stored electromagnetic energy—a quantity essential for calculating the quality factor, which reflects the intrinsic bandwidth of the considered electromagnetic system. A novel paradigm is proposed to determine the stored energy in the time domain leading to the method, which exhibits positive semi-definiteness and coordinate independence, i.e. two key properties actually not met by the contemporary approaches. The proposed technique is compared with an up-to-date frequency domain method that is extensively used in practice. Both concepts are discussed and compared on the basis of examples of varying complexity.


Sign in / Sign up

Export Citation Format

Share Document