Based on analyzing the communication module of a wireless monitoring system, this article designs the hardware and software with nRF24L01. Then it emphasizes on analyzing the question of anti-interference and low power consumption. Through researching the process of communication using the Petri net model, it adds the acknowledgement signal and changes the radio-frequency channel to respectively resolve the problem of interference from the system of frequency hopping spread spectrum and direct sequence spread spectrum. And it uses the mechanism of intermittent transmission to reduce power consumption. Through experimentation, the communication module is of small size, excellent anti-interference ability, low power consumption and high data rate. It is of high practical value and significant use for reference.

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This paper analyzed the type of mini-type antenna, studied the miniaturization technique based on simulation in depth, and finally designed the high-performance micro-strip antenna. The advantages of micro-strip antenna are light-weight, compact size, relatively thin thickness, and so on. However, it still needs aggressive miniaturization to satisfy the requirements of encapsulation. Techniques for miniaturization of antenna mainly include a ground plane, double-layer patch, shorting pin or wall, lossless dielectric substrate and the spiral structure. The techniques of multi-layer and shorting wall can narrow down the resonant frequency and attain bandwidth enhancement. Nonetheless, they have a complicated structure. Thus, simulation researched the influence of the surrounding tissue in detail, the position relation of shorting pin and the feed point, the substrate parameters and the structure parameters of the spiral antenna on performance. At last, through the techniques of the shorting pin, high permittivity substrate and the spiral shape, two Archimedean micro-strip patch antennas were developed for wireless capsule endoscope. The antenna has the bandwidth of about 300 MHz, the minimum voltage standing-wave ratio of 1.14:1, and the diameter of 8.3 mm. Therefore, the antenna can offer excellent performance for transmitting image data.

In recent years, the development of microelectrode arrays and multichannel recordings has provided opportunities for high‐precision detection in signal processing. The study of neuronal frontal potentials has been rapidly emerging as an important component in brain‐computer interface and neuroscience research. Neuronal spike detection provides a basis for neuronal discharge analysis and nucleus cluster identification; its accuracy depends on feature extraction and classification, which affect neuronal decoding analysis. However, improving the detection accuracy of spike potentials in highly noisy signals remains a problem. IThe authors propose a heuristic adaptive threshold spike‐detection algorithm that removes noise and reduces the phase shift using a zero‐phase Butterworth infinite impulse response filter. Next, heuristic thresholding is applied to obtain spike points, remove repetitions, and achieve robust spike detection. The proposed algorithm achieved an average accuracy of 95.40% using extracellular spiked datasets and effectively detected spikes.

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