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Photonic crystals are periodic structures made of insulators. They are the best option to design biosensors. In this paper, a photonic crystal biosensor containing insulation rods in the air was designed and simulated. This biosensor was used as a photonic crystal circular nano-ring between the internal and external waveguides. At the end of the internal waveguide, a defect exists to create an increase in the coupling distance. This causes the quality factor and resonant wavelength displacement to increase. The purpose of designing this sensor is to check blood ingredients. After connecting to a measuring rod, this sensor shows different refractive indices. Another important characteristic of the proposed structure is that mostly radiuses of dielectric rods are identical. This causes the sensor construction to be easy. The plane-wave expansion (PWE) method is utilized to calculate the band structure. The results show that a photonic band gap (PBG) with a wavelength from 1.26 μm to 1.92 μm is created in this distance where no wavelength can spread.

In this paper, a miniaturized substrate integrated waveguide filter on the magnetized ferrite is presented. The proposed filter has a small size, high power transmission capability, relatively good bandwidth, and tunable frequency bandwidth. This filter is tunable due to the magnetic bias applied to the ferrite substrate. Compared to the tunable filters reported in previous references based on PIN diode, varactors, and mechanical changes, the proposed filter has a relatively wide adjustment on the operation frequency. Using this method dramatically reduces the complexity of the external control system. This tunable filter is optimized using the Ansoft HFSS software and then fabricated. The measured operating frequency of the filter is tunable from 5.3 to 7.15 GHz by changing the magnetic bias from 100 Oe to 1100 Oe. In the frequency range of 5.55 to 6.95 GHz, an insertion loss of less than 1.1 dB and a return loss of better than 20 dB are achieved. A good agreement between the simulation and experimental results was achieved.

Inertial navigation is an edge computing-based method for determining the position and orientation of a moving vehicle that operates according to Newton's laws of motion on which all the computations are performed at the edge level without need to other far resources. One of the most crucial struggles in Global Positioning System (GPS) and Inertial Navigation System (INS) fusion algorithms is that the accuracy of the algorithm is reduced during GPS interruptions. In this paper, a lowcost method for GPS/INS fusion and error compensation of the GPS/INS fusion algorithm during GPS interruption is proposed. To further enhance the reliability and performance of the GPS/INS fusion algorithm, a Robust Kalman Filter (RKF) is used to compensate the influence of gross error from INS observations. When GPS data is interrupted, Kalman filter observations will not be updated, and the accuracy of the position will continuously decrease over time. To bridge GPS data interruption, an artificial neural network-based fusion method is proposed to provide missing position information. A well-trained neural network is used to predict and compensate the interrupted position signal error. Finally, to evaluate the effectiveness of the proposed method, an outdoor test using a custom-designed hardware, GPS, and INS sensors is employed. The results indicate that the accuracy of the positioning has improved by 67% in each axis during an interruption. The proposed algorithm can enhance the accuracy of the GPS/INS integrated system in the required navigation performance.

In this study, the effect of length of the stub on the formation of the Fano resonance in structures which possess a metal-insulator-metal (MIM) waveguide coupled to rectangular cavities by the stub is investigated theoretically and numerically. The resulting Fano resonance is used to design an ultrawideband bandstop filter that can filter all wavelengths between two telecommunication windows of λ = 850 n m and λ = 1310 n m . The structure is based on two rectangular cavities coupled to the MIM waveguide by stubs that are located at an adjusted distance from each other; the interference superposition of reflected and transmitted waves from each other will make this filtering phenomenon. The center wavelength of the bandstop of the structure is highly adjustable by changing the dimensions of the structure. The theoretical and the numerical results are, respectively, based on the transmission line model and the finite-difference time-domain method. The theoretical results comply well with the numerical ones. To analyze the Fano resonance, temporal coupled mode theory is also exploited. The proposed structure has significant applications in highly integrated optical circuits.