Wireless Data Transmission for Fingerprint Handheld Devices

Technical design of a star-topology, master–slave wireless data transmission system using nRF905 to distribute and collect fingerprint authentication data from handheld devices.

Face Detection on NXP S32V Vision Platform

Implementation of real-time face detection on the NXP S32V vision platform: IMX224 capture, VSDK ISP flow, NCNN/OpenCV porting and Qt demo for ADAS driver monitoring.

What to Do When a Phone Touchscreen Fails in Winter

Practical troubleshooting for capacitive touchscreen unresponsiveness in cold conditions: causes, surface and software checks, and step-by-step fixes before repair.

Gaussian Filter: Principles and Implementation

Explanation of Gaussian filter, kernel generation and separable implementation in C++/OpenCV, with guidance on sigma selection and performance trade-offs.

Three Under-Display Fingerprint Technologies

Technical overview of under-display fingerprint technologies—optical, ultrasonic, and capacitive—examining principles, trade-offs, production challenges, and market maturity.

Improving 3D Recognition with 1D ToF in Smartphones

Technical article about electronics and hardware engineering.

Capacitive Touchscreen Structure and Principle

Technical overview of capacitive touchscreen structure and sensing principle, covering ITO layers, electrode placement, coupling capacitance, and touch coordinate calculation.

CNN Classification of Large-Scale Wearable Motion Data

Evaluation of CNNs on wearable sensor time series for 50-class gym exercise classification, comparing 9x784, 3x784x3 and 84x84 inputs; best config reached 92.1% accuracy.

Touch Switch Circuit Using Dual D Flip-Flops

Technical overview of a touch switch circuit using a 4013 dual D flip-flop, covering monostable timing, input protection, relay drive and toggle on/off operation.

Microwave Motion Sensor Switch: Principle and Wiring

Microwave motion sensor switch: Doppler-effect detection, wiring and functions including sensitivity, anti-interference, ambient light control, timing, and concealed installation.