Polyaxial vs. Monoaxial Angular Stability in Osteosynthesis with Internal Fixators for Complex Periarticular Fractures

2010 ◽  
Author(s):  
P. Sirbu ◽  
W. Friedl ◽  
N. Schwarz ◽  
R. Asaftei ◽  
M. Bar ◽  
...  
Keyword(s):  
Angular Stability ◽  
Internal Fixators

Dual-Band Band-Pass Frequency Selective Surface Based on the Matryoshka Geometry with Angular Stability and Polarization Independence

2020 ◽  
Author(s):  
Alfredo Gomes Neto ◽  
Jefferson Costa e Silva ◽  
Alexandre Jean Rene Serres ◽  
Marina de Oliveira Alencar ◽  
Ianes Barbosa Grecia Coutinho ◽  
...  
Keyword(s):  
Frequency Selective Surface ◽  
Angular Stability ◽  
Dual Band ◽  
Band Pass ◽  
Frequency Selective

scholarly journals C-Band and X-Band Switchable Frequency-Selective Surface

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 476
Author(s):  
Umer Farooq ◽  
Adnan Iftikhar ◽  
Muhammad Farhan Shafique ◽  
Muhammad Saeed Khan ◽  
Adnan Fida ◽  
...  
Keyword(s):  
Bottom Layer ◽  
Frequency Selective Surface ◽  
Transverse Magnetic ◽  
Unit Element ◽  
Angular Stability ◽  
Band Spectrum ◽  
Pin Diode ◽  
Pin Diodes ◽  
X Band ◽  
Frequency Selective

This paper presents a highly compact frequency-selective surface (FSS) that has the potential to switch between the X-band (8 GHz–12 GHz) and C-band (4 GHz–8 GHz) for RF shielding applications. The proposed FSS is composed of a square conducting loop with inward-extended arms loaded with curved extensions. The symmetric geometry allows the RF shield to perform equally for transverse electric (TE), transverse magnetic (TM), and 45° polarizations. The unit cell has a dimension of 0.176 λ0 and has excellent angular stability up to 60°. The resonance mechanism was investigated using equivalent circuit models of the shield. The design of the unit element allowed incorporation of PIN diodes between adjacent elements for switching to a lower C-band spectrum at 6.6 GHz. The biasing network is on the bottom layer of the substrate to avoid effects on the shielding performance. A PIN diode configuration for the switching operation was also proposed. In simulations, the PIN diode model was incorporated to observe the switchable operation. Two prototypes were fabricated, and the switchable operation was demonstrated by etching copper strips on one fabricated prototype between adjacent unit cells (in lieu of PIN diodes) as a proof of the design prototypes. Comparisons among the results confirmed that the design offers high angular stability and excellent performance in both bands.

Miniaturized frequency selective surface with high angular stability

Frequenz ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zain Ul Abidin ◽  
Qunsheng Cao ◽  
Gulab Shah ◽  
Zaheer Ahmed Dayo ◽  
Muhammad Ejaz
Keyword(s):  
Resonant Frequency ◽  
Electric Field Distribution ◽  
Equivalent Circuit Model ◽  
Surface Current ◽  
Frequency Selective Surface ◽  
Angular Stability ◽  
Working Mechanism ◽  
Low Profile ◽  
Simple Geometry ◽  
Frequency Selective

Abstract In this paper, a miniaturized bandstop frequency selective surface (FSS) with high angular stability is presented. Each FSS element consists of four sets each consisting eight octagonal concentric interconnected loops. The four sets are connected with each other through outermost octagonal loop. The unit size is miniaturized to 0.066 λ0 at the resonant frequency of 1.79 GHz. The proposed configuration achieves excellent angular stability (only 0.025 GHz resonant frequency deviation is observed upto 83° oblique angles). The working mechanism of FSS is explained with the help of equivalent circuit model (ECM), electric field distribution, and corresponding surface current distribution. A prototype of the designed bandstop FSS is fabricated to verify the simulated frequency response. The experimental results are consistent with the simulation results. Simple geometry, low profile, high angular stability, and compact cell size are prominent features of the proposed structure.

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