Jung Hwan Hwang

TAP: touch-and-play

An intuitive context aware service between two devices is possible using touch with the intrabody communication. Using this technology, users with multimedia devices may simply touch them to establish network connection, transfer data, and provide the required service; hence the name Touch-And-Play (TAP). Using TAP, users can disclose their context by touching the specific device. For instance, a user carrying a digital camera touches the TV to begin a slide show or a printer to print a photo. TAP is expected to enable the provision of intuitive, context-aware service. This paper discusses the feasibility of TAP and its application in user interface.

Effects of ground electrode on signal transmission of human body communication using human body as transmission medium

In this paper, the measurement results on the effects of ground electrode according to the transmission distance are presented. A biological tissue-equivalent phantom has been used in the measurement of a previous paper, but a real human body is used in this paper. Also, the measurement results are analyzed by EM simulation. In the previous papers K. Fujii et al. (2003)-(2002), the simulation model for human body has been composed of only muscle tissue. In this paper, a more accurate model composed of muscle and other tissues is used during the simulation. Finally, the method by which a ground electrode can be used more efficiently is proposed based on the measurement results

Context aware service using intra-body communication

An intuitive context aware service between two devices is possible using touch with the direct digital intra-body communication. Using this technology, users with multimedia devices may simply touch them to establish network connection, transfer data, and provide the required service; hence the name touch-and-play (TAP). Using TAP, users can disclose their context by touching the specific device. For instance, a user carrying a digital camera touches the TV to begin a slide show or a printer to print a photo. TAP is expected to enable the provision of intuitive, context-aware service. This paper discusses the communication protocol of TAP and its application

Measurement results of human body's signal loss with multiple subjects for human body communication

Human body communication is being recognized as a new communication technology that can replace wire and wireless technologies in a body area network (BAN). In this approach, the body is used as a medium for transmitting data between mobile devices or between a mobile device and a peripheral device. A user simply touches the devices, and then the devices are connected to each other via the body of the user, and they can then communicate without using a wire or wireless technology. This paper presents a measurement result on signal losses of the human body. Signal losses were obtained from measurements of multiple subjects. In the measurements, the grounds of a transmitter and a receiver were properly isolated from each other and from the earth ground for an accurate measurement. Finally, channel properties were analyzed by using the measured signal losses.

Effect of load impedance on the signal loss of human body communication

In this paper, the effect of load impedance was presented and analyzed based on the lumped model for human body communication. The signal loss decreased as the load impedance increased, but it was saturated gradually because of the leakage impedance.

Reverse effect of ground electrode on the signal loss of human body communication

In this paper, we analyzed the effects of the ground electrode, especially the reverse effect in which the signal loss increases by the ground electrode. We measured how the signal loss varies in relation to the ground electrode. Furthermore, we simulated the current distribution to analyze the effects of the ground electrode. In other papers, the body has an artificial posture in which two arms and a shoulder formed a straight line. In our approach, we measured the signal loss of a person with a natural posture for actual human body communication; that is, the persons two arms and shoulder did not form a straight line. Also, we reflected the modified posture of the body in the simulation model.

Analysis of signal interference in human body communication using human body as transmission medium

In this paper, the measurement results on the signal interference of human body communication are presented. A real human body is used in the measurement. Also, the measurement results are analyzed by EM simulation. Finally, the frequency band where the human body communication can be used without the interruption by signal interference is proposed based on the measurement and simulation results

Receptive properties of the human body of emitted electromagnetic waves for energy harvesting

This paper investigates the receptive properties of the human body of emitted electromagnetic waves as part of an investigation into the possibility of energy harvesting from the electromagnetic waves using the human body. Voltages received as the human body functions as an antenna were measured and compared with simulation results. The received voltages in a general electromagnetic environment were also estimated.

Performance evaluation of human body communication system for IEEE 802.15 on the effect of human body channel

The root mean square (RMS) delay spread and coherence bandwidth are examined based on measurement for a wide band human body channel. Using the results, the relation between these two wideband channel parameters is evaluated. The inter-symbol interference (ISI) effect on the performance of the frequency selective digital transmission (FSDT) is investigated by modeling the time dispersive human body channel as a finite impulse response (FIR) filter. Then, the compatible required transmitter power is computed for a reliable FSDT communication link.

Effects of transmitter’s location on the signal loss of the human body communication

When the transmitter is held in the hand, the signal loss is larger than when it is attached to the wrist. When it is held in the hand, the coupling to the ground plane becomes strong because the palm is located on the coupling path to the ground plane. Therefore, much current near transmitter is distributed in the opposite direction of the receiver and less current flows to the receiver.