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Concurrent Dualband Front-End Elements for NIVSD Sensors
Published in Brijesh Iyer, Nagendra Prasad Pathak, Multiband Non-Invasive Microwave Sensor, 2018
Brijesh Iyer, Nagendra Prasad Pathak
In general, a microstrip transmission line (TL)–based DC bias tee network consists of a quarter-wave impedance transformer with high-characteristic impedance. Such networks work at the designed frequency and its odd harmonics. However, it is not useful in a multiband circuit where high input impedance is required at multiple uncorrelated frequencies. Hence, a concurrent dualband DC bias network is proposed which is realized using microstrip TL sections only. Figure 4.6 shows the DC bias network.
Design of Conventional and DBF Microstrip Antenna Arrays
Published in D. G. Fang, Antenna Theory and Microstrip Antennas, 2017
Consider the microstrip transmission line quarter-wave impedance transformer shown in Figure 6.14. The formulas for voltage, current and power are given in the following according to the derivation in Chapter 4. The results in Figure 6.14 may be obtained from (6.3.1)–(6.3.4).
Close link between Fabry–Pérot resonance and natural-resonance frequencies
Published in Waves in Random and Complex Media, 2023
Ugur Cem Hasar, Gokhan Ozturk, Yunus Kaya, Joaquim José Barroso, Omar M. Ramahi, Mehmet Ertugul
Aside from the natural-resonance frequencies, Fabry–Pérot resonance frequencies can be utilized to determine electromagnetic properties and also to detect and identify defects with materials [8–11]. These frequencies, which are named as the thickness-resonance frequencies (or half-wave window), are excited when both sides of a material are surrounded by identical media under the case that the thickness of material (L) is an integer multiple of one half-wavelength (λ) within the material at the operating frequency [12]; that is, where m is a positive integer number. Another kind of resonance, similar to the Fabry–Pérot resonance, arises when both sides of a material are surrounded by dissimilar materials under the case that L is an odd multiple of ; that is, . For example, short-circuit termination of an air-material structure is a special case of this resonance [13]. This type of resonance is also referred to as the quarter-wave impedance transformer.