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Convolution neural network (CNN) presents high robustness in computer vision applications. In state-of-the-art methods, CNN is being used in EEG processing for various classification and problem solving. To enable EEG to fit in the CNN architecture, data conversion of EEG has to be done. The ways of data conversion need to be investigated in order to fully utilize the information. From the study, it was found that the simplest way of re-arranging the signal is by creating a two dimensional matrix of channels versus time points. There are approaches that compute Pearson correlation coefficients and fit them into a two dimensional matrix to represent the input signal. There are also methods which extract frequency components and fit them in matrix structure as channels versus frequency components, such as power spectral density. Other approaches includes graph representation and wavelet components.

This paper reports the technical design of millimeter wave (mm-Wave) low noise amplifier (LNA). The fast-growing wireless communication market and the necessity of a higher data rate certainly drive the radio frequency (RF) system towards the mm-Wave technology. The 28 GHz channel band possesses a large amount of raw bandwidth space with a spectrum allocation that exceeds the bandwidth of 1 GHz. The mm-Wave cellular wireless system is developed to address with a worldwide wireless bandwidth shortage. The 28 GHz LNA is used to amplify a very low signal at 28 GHz and minimize the present of unwanted additional noises. The performances of single and cascaded LNAs are analyzed and presented. The footprint design of LNA is fabricated on ROGERS 4003 C with permittivity of 3.38. The off-the-shelf commercial MMIC LNA is mounted and matched to 50 Ω. The fabricated LNA is analyzed based on the output power levels and signal gains. The minimum and maximum gains for a single LNA are recorded at 11 dB and 14.83 dB respectively. 22.05 dB is verified as the lowest gain for the cascaded LNA while the highest gain is indicated at 28.83 dB when the RF signal input power is quoted at −74.54 dBm.

This paper reports the architecture design of 26–32 GHz downconverter passive double-balanced mixers used for RF front-end circuit design. The performance of the simulated lumped hybrid-ring coupler double-balanced mixer and the monolithic microwave integrated circuit (MMIC) double-balanced mixer are going to be compared throughout this paper. Both designs are compared based on the conversion gain, intermediate frequency (IF) return loss and RF to IF signals isolation. The MMIC surface mount package is mounted in a 50 Ω test fixture which eliminates the need for wire bonding.

The presence of dark swirls or rings in luminescence image of a solar cell is usually caused by oxygen precipitate during fabrication of a solar cell. This is not desirable as it could cause a drop in efficiency of the cell. An application of gray level co-occurrence matrix (GLCM) is presented to detect such dark swirls or rings in both photoluminescence (PL) and electroluminescence (EL) images. It was found that the energy values calculated from a GLCM has a good separation between defective and non-defective images. A threshold was established based on the energy values and was then used to perform classification. Experiments have shown that this method provides a good result with minimal under-rejection and over-rejection rate for both PL and EL.

This paper reports the passive frequency multiplier designs used to obtain a pre-determined multiplies output frequency of 20 to 26 GHz in modern communication system. The performances between the simulated lumped frequency multiplier modeling design and the Monolithic Microwave Integrated Circuit (MMIC) frequency multiplier design are going to be compared throughout this paper. Both designs are analyzed based on the results of the output power frequency obtained. The MMIC frequency multiplier fabricated using Pseudomorphic High Electron Mobility Transistor (PHEMT) technology and packaged into Quad Flat No-leads (QFN) package with Surface Mount Technology (SMT) application. The commercial MMIC surface mount package is matched to 50 Ω and fully blocked.

This paper presents the effect of variation of diameter and height of DR to the resonant frequency and radiation pattern of DRA. Analysis was carried out on the DR with diameter of 10.66 mm and height of 4.4 mm. The simulated and measured resonant frequencies were 3.67 and 3.77 GHz, respectively. The E-plane radiation pattern of CDRA was bi-directional pattern. The analysis was based on the CST simulation which varied the thickness and height of DR with the same increment and decrement of 1 mm. The resonant frequency of CDRA shifts significantly when the height of DR is varied, in contrast to the variation of DR’s diameter. The radiation pattern of antenna does not change when the dimension (height or diameter) of DR were altered.