In-Gi Lim

Human body communication system with FSBT

There are some leakage radiations from human body depending on incoming signals to it. As there are many noises in the frequency band spanning several MHz, human body communication (HBC), which is a technique to transfer various information through the human body as a communication channel, requires a limitation of frequencies and data rates to support a reliable network that can cope with interference from adjacent users and electrical devices. This paper proposes a frequency selective baseband transmission (FSBT) for HBC. FSBT requires no RF/IF components or overhearing in sleep mode as a service based on Touch-And-Play (TAP). The proposed HBC system supports high reliability, low power consumption, and low cost through FSBT. We achieved a biterror rate of 10–6 at 2 Mbps without forward error correction and verified the functions of the prototypes to transfer streaming data or image files between ultra-mobile PCs, or an ultra-mobile PC and printer.

A Method of Increasing Data Rate for Human Body Communication System for Body Area Network Applications

Human body communications (HBC), which have been standardized in IEEE 802.15.6 standard for wireless body area networks (WBAN), provides a maximum data rate of 1.3125 Mbps through frequency selective digital transmission (FSDT). This paper reviews FSDT and proposes a modified FSDT (MFSDT). By exploiting the efficient modification of the FSDTs transmitter structure, MFSDT achieves a maximum data rate of 3.9375 Mbps, and the decoding complexity of MFSDT increases linearly with an increase in the data rate. In addition, FSDT and MFSDT performance are investigated with respect to the effects of the transmit filter provided to meet transmit spectral mask requirements, and a human body channel modeled as a finite impulse response filter.

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.

Improving data rate in the human body communications

The proposed transmitter structure for human body communications improves the data rate with a simple modification of the conventional frequency selective digital transmitter. A maximum data rate is increased by 75 percent, from 1.3125 Mbps to 2.2969 Mbps while the transmitted signals are satisfied with the transmit spectral mask. By the proposed detection scheme, the receiver does not require additional Hamming distance calculations in the maximum likelihood detector.

10Mbps human body communication SoC for BAN

A plurality of wearable devices have appeared recently. The requirements of communication method for wearable applications are wearing comfort, easy use with intuitiveness and low power consumption. In this paper, 10Mbps human body communication method which has extremely low power consumption is presented. The differences between HBC in IEEE 802.15.6 and proposed 10Mbps HBC, SoC architecture and implementation, performance of evaluation board and application are discussed.