Dual-frequency dual orthogonal polarization wave multiplexing using decoupled pixels based on Holographic technique

Mostafa Movahhedi; Nader Komjani

doi:10.1364/oe.391380

Design of a High-Isolation 35/94-GHz Dual-Frequency Orthogonal-Polarization Cassegrain Antenna

IEEE Antennas and Wireless Propagation Letters ◽

10.1109/lawp.2016.2633284 ◽

2017 ◽

Vol 16 ◽

pp. 1297-1300 ◽

Cited By ~ 5

Author(s):

Jie Wang ◽

Jun xiang Ge ◽

Yong Zhou ◽

Han Xia ◽

Xian zhi Yang

Keyword(s):

Orthogonal Polarization ◽

Dual Frequency ◽

High Isolation ◽

Cassegrain Antenna

Download Full-text

Dual-Frequency Miniaturized Substrate Integrated Waveguide Quarter-Mode Cavity-Backed Antenna Based on Minkowski Fractal Gap with Orthogonal Polarization Radiation Characteristics

International Journal of Antennas and Propagation ◽

10.1155/2019/1816763 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Zihao Fu ◽

Tianliang Zhang ◽

You Lan ◽

Tianhai Wu ◽

Wenxing Huang ◽

...

Keyword(s):

Electric Field ◽

Field Distribution ◽

Electric Field Distribution ◽

Polarization Characteristic ◽

Orthogonal Polarization ◽

Substrate Integrated Waveguide ◽

Dual Frequency ◽

Third Order ◽

Resonant Modes ◽

Minkowski Fractal

A novel quarter-mode substrate integrated waveguide miniaturized cavity-backed antenna loading Minkowski fractal gap is presented in this paper. Firstly, the resonant frequency of the rectangular substrate integrated waveguide resonator is reduced by etching the fractal gap in the resonator to achieve miniaturization. In addition, because of the symmetry of electric field distribution in second and third order resonant modes, the cavity can be segmented into a quarter-mode and the other order resonance modes with asymmetric electric field distribution can be suppressed according to the cavity model theory. Hence, the cavity size is further reduced. The dimension of designed antenna is 0.26λ0×0.26λ0 (λ0 is the wavelength in free space; in this paper, the corresponding wavelength is 3.6 GHz). Moreover, the orthogonal polarization of the proposed antenna in two frequency bands is achieved because the electric field is orthogonal in second and third order resonant modes. This dual-frequency orthogonal polarization characteristic enables antenna to communicate in two working bands and has good channel isolation. The simulated and measured results are consistent. The antenna gain is 4.67dBi and 3.4dBi, respectively, at 3.7GHz and 4.6GHz.

Download Full-text

Structured methods for improving flow measurement accuracy in pipelines

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-5-30-35 ◽

2020 ◽

pp. 30-35

Author(s):

Gurami N. Akhobadze

Keyword(s):

Flow Measurement ◽

Measurement Accuracy ◽

Directional Coupler ◽

Signal To Noise Ratio ◽

Scattered Wave ◽

Orthogonal Polarization ◽

Flow Sensors ◽

Information Signal ◽

Mass Flows ◽

Processing Device

In the age of digital transformation of production processes in industry and science the development and design of intelligent flow sensors for granular and liquid substances transferring through pipelines becomes more important. With this in view new approaches for improving the accuracy of microwave flowmeters are proposed. Taking into account the characteristics ofelectromagnetic waves propagating through a pipeline, a wave scattered by inhomogeneities of the controlled medium is analyzed. Features of the transformation of the polarized scattered wave limiting the geometric dimensions of the pipeline and optimizing the values of the useful scattered signal are revealed. Expediency of collection of the information signal with orthogonal polarization of the scattered wave and through a directional coupler is substantiated. The method of estimating the measurement accuracy with reference to the signal-to-noise ratio at the input of the processing device is given. The research results can be used in cryogenic machine engineering to measure volume and mass flows of liquid cryogenic products.

Download Full-text