Showing papers by "Jianqing Wang published in 2018"

A Wideband Miniaturized Implantable Antenna for Biomedical Application at HBC Band

Abstract: In this study, a wideband implantable antenna with a small size of 3 cm is designed to operate at Human Body Communication (HBC) band. The proposed implant antenna is realized with two layer of non-equally spaced helical copper foil for dual-resonance frequency band in which −10 dB impedance bandwidth is 15.66 MHz (48.21%). The miniaturization of the antenna is realized by forming the copper radiation element on two layers of flexible magnetic sheet. Simulation results in a cubic tissue-equivalent phantom demonstrates that the proposed wideband antenna is a useful and capable candidate for high-speed transmission in implant biomedical applications at HBC band.

Development and In Vivo Performance Evaluation of 10–60-MHz Band Impulse-Radio-Based Transceiver for Deep Implantation Having 10 Mbps

Abstract: In view of the requirements for high-speed, highly reliable wireless implant communication, we have developed an implant transceiver working at a 10–60-MHz band. The developed transceiver is based on an impulse radio technology with multipulse position modulation to increase the communication speed and reliability, and utilizes the automatic equalization technique to suppress waveform distortion and intersymbol interference due to frequency-dependent tissue properties. The transmit antenna has a dimension of $2.6\,\,\text {cm} \times 1.6\,\,\text {cm} \times 1.6$ cm and a relative bandwidth of 16% by forming the radiation elements on a flexible magnetic sheet for miniaturization. Through an in vivo experiment on a living swine, we have shown the feasibility of implant communication in a depth up to 26 cm with a minimum data rate of 10 Mbps. These results demonstrate the superiority of this new technology over all others reported so far in the literature.

Experimental evaluation of 30 MHz band implant communication using automatic equalisation technique

Abstract: Wireless body area communication technology is attracting much attention in healthcare and medical applications. For reliable and high-speed implant transmission, the authors previously developed an in-body transceiver at around 30 MHz. However, as the distance between the transmit antenna and the receive antenna gets longer, its bit error rate (BER) performance gets deteriorated. This is because that an implanted channel can cause severe waveform distortion and consequent inter-symbol interference (ISI). Meanwhile, the equalising technique provides a powerful means to counteract ISI. In this study, they developed an automatic equaliser for the 30 MHz band implant communication. Moreover, they implemented the equaliser on a field programmable gate array board and evaluated the BER performance with a biological equivalent liquid phantom. The measurement result shows that their developed equaliser can significantly improve the communication performance in the implant channel.

Development of wealable ECG based on human body communication technology

Abstract: In daily healthcare monitoring, wearable electro-cardiogram (ECG) with wireless function is essential because it is easy to use and helpful to early detection of cardiac diseases. However, various electromagnetic (EM) interference issues need to be solved for its normal use. In this study, we developed a wearable ECG which employs the extremely weak radio band and a wideband human body communication (HBC) technology. The realized wireless function provides higher anti-interference performance and more reliable ECG signal acquisition, compared to usually used Bluetooth technology at 2.4 GHz.

A study on nonlinear effect of modulated radio signals at 1 kHz on stimulus response

Abstract: Stimulus response caused by electromagnetic fields can be applied to medical treatments. However, it is well known that membrane potential on nerve cells has nonlinearity, so in the case of modulated signals, it is important to analyze the nonlinear stimulation effect based on a nerve cell model. In this paper, we paid attention to Hodgkin-Huxley (HH) model as the nerve cell model, and evaluated the stimulus response when nerve cells were exposed to low-frequency modulated radio signals based on the HH model. The stimulus response due to the modulated radio signals with various kinds of duty cycles and induced amplitudes were evaluated and discussed.