Body Channel Communication Transceiver Research Articles

Design and performance analysis of manchester coder-based body channel communication using FPGA

In general, the Body Channel Communication (BCC) is used to transmit human physiological signals over vast distances. Also, the Error-correcting codes can detect and rectify faults in long-range data transmission. Data is encoded in a predetermined manner for secure transmission. In this paper, a Manchester encoding-based high throughput architecture is proposed for a body channel communication system with a low-power operation mode. Further, the Manchester encoder is designed for high throughput performance with a low complexity architecture, and an analog front-end processing circuit which includes two stage pre-amplifiers. Also, the transmission rate on the BCC transceiver side is boosted by the maximum Consecutive Identical Digit (CID), which is limited by Manchester codes. The Manchester code format is generated by encoding the sensed data. Additionally, a full gain buffer is used to reduce data loss and hardware overhead. Results demonstrate that the suggested Manchester encoder is implemented in 90 nano meter (nm) technology, and the 10 Megabits per second (Mbps) data rate is obtained with a configurable operating frequency ranging from 1 to 100 Megahertz (MHz).

A 2m-Range 711μW Body Channel Communication Transceiver Featuring Dynamically-Sampling Bias-Free Interface Front End.

Body Channel Communication (BCC) utilizes the body surface as a low-loss signal transmission medium, reducing the power consumption of wireless wearable devices. However, the effective communication range on the human body is limited in the state-of-the-art BCC transceivers, where the signal loss between the body surface and the BCC receiver remains one of the main bottlenecks. To reduce the interface loss, a high input impedance is desired by the BCC receiver, but the DC-biasing circuits decrease the input impedance. In this work, a dynamically-sampling IFE is proposed to eliminate the DC voltage bias, resulting in a 90kΩ high input impedance and a 94dB RF-IF conversion gain to reduce the interface loss in long-range BCC applications. The BCC transceiver chip is fabricated in 55nm CMOS process, taking a die area of 0.123mm2. Measured results show that the chip extends the BCC range to 2m for both the forward and backward paths, where the transmitter and receiver consume 711μW power in total.

Design of high‐speed data transfer turbo code for body channel communication transceivers

SummaryIn this work, a digital differential transmitter based on low‐power wireless compensation transceiver for body channel communication (BCC) is proposed. Further, the proposed transceiver is composed of Touch Status Detection Unit (TSDU), Wireless Status Compensation Unit (WSCU), and a reconfigurable preamplifier. Initially, the human body channel environment for wireless communication is investigated based on properties from 1 to 100 MHz. Further, the turbo code‐based encoding scheme is used to encode the data before transferring the data on the transmitter side. Also, the proposed error‐correcting parallel turbo decoder using a modified step‐by‐step algorithm is presented. The turbo code‐based decoding scheme is used to recover the error‐free transmitted data at the receiver side. Results demonstrate that the proposed BCC transceiver is designed using 90 nm CMOS technology and it is observed that the proposed BCC transceiver has utilized an area of 600mm2. Also, the maximum data rate achieved by a proposed BCC transceiver was 100 Mbps, and the overall transceiver power consumption is 0.42 mW, and energy for communication is 0.02 nj/b.

Design of a human body channel communication transceiver using convolutional codes

This paper presents a wideband signaling body channel communication (BCC) transceiver that uses the convolutional encoding method. The proposed transmitter uses the convolutional encoding method to increase the data reliability, and the modulated data are transmitted directly to a human body through a SMA cable and an electrode. In the receiver side, the oversampling phase detection clock and data recovery circuit with convolutional encoding method recovers the clock and data and increases 1.8x random data jitter tolerance (i.e., 50ns–90ns) at 10−9 BER. The proposed BCC transceiver, except for the pre-amplifier of the RX, can be realized as a synthesizable digital IP. Thus, the proposed design can be ported to different processes in a short time. The feasibility of the proposed transceiver architecture was verified by the FPGA, and no bit errors occurred over 108 bits received at data rate 3.125 Mbps in transmission distance under 140 ​cm, which indicates the transceiver is very suitable for high-performance BCC applications.

The Role and Challenges of Body Channel Communication in Wearable Flexible Electronics.

Flexible electronics are compatible with film substrates that are soft and stretchable, resulting in conformal integration with human body. Integrated with various sensors and communication ICs, wearable flexible electronics are able to effectively track human vital signs without affecting the body activities. Such a wearable flexible system contains a sensor, a front-end amplifier (FEA), an analog-to-digital converter (ADC), a micro-controller unit (MCU), a radio, a power management unit (PMU), where the radio is the design bottleneck due to its high power consumption. Different from conventional wireless communications, body channel communication (BCC) uses the human body surface as the signal transmission medium resulting in less signal loss and low power consumption. However, there are some design challenges in BCC, including body channel model, backward loss, variable contact impedance, stringent spectral mask, crystalless design, body antenna effect, etc. In this paper, we conduct a survey on BCC transceiver, and analyze its potential role and challenges in wearable flexible electronics.

Energy efficient low density parity check scheme for body channel communication using FPGA

An arrangement of an on-body to on-body thin-ranging channel along with various issues is deliberated. Time-area appearances of body channel communication (BCC) of human are considered by using a Field Programmable Gate Array (FPGA) at variable transmission distances and signal frequencies. In Human body channel communication (HBCC), wide band signaling (WBS) technique is characterized as well as correlated with existing devices and are more stable and expend very less power. But based on the movement of human body, wide band signaling is more sensitive. The WBS constructed BCC is established in FPGA platform at diverse broadcast distances and signal frequencies by using Non Return to Zero (NRZ) encoded information. In this strategy presented, the information encoded by NRZI data at the transmitter part are driven accurately to the human based BCC. At the receiver part, the FPGA enhanced the conventional signals and in addition, the proposed LDPC technique circuit enhances the accepted frequency decoded point information from irregular nodes. The presented LDPC technique based wide band signaling BCC transceiver is acknowledged in the typical 65 nm CMOS executing process. The core region is found as 0.133 mm2. Power consumption of LDPC technique based WBS- BCC transceiver is 1.07 mW at 40Mb/s. The bit energy is 0.02 nJ/b.

A Four-Camera VGA-Resolution Capsule Endoscope System With 80-Mb/s Body Channel Communication Transceiver and Sub-Centimeter Range Capsule Localization

A small form-factor, lightweight wireless capsule endoscope (WCE) system with body channel communication (BCC) transceiver ICs is proposed for VGA-resolution image transferring and capsule localization. The transceiver ICs are composed of capsule chip and receiver chip, implemented in a 65-nm CMOS process. In the capsule side, the proposed system provides 360° image capturing through four-camera integration to reduce the miss rate. Also, a dual-band pulse-shaping BCC transmitter is proposed to enable low-power (<1 mW), high-speed (80 Mb/s) image transmission. In the receiver side, contact attenuation compensated-received signal strength indicator (CAC-RSSI) is proposed to increase the capsule localization accuracy. The external system is composed of eight-receiver nodes that allow signal demodulation and localization of the capsule. To reduce transceiver payload and system power consumption, image encoder is implemented in the capsule. The transceiver IC is integrated into the capsule system and verified with body mimicking phantom. The proposed system satisfies compatibility with medical grade diagnosis by operating longer than 8 h with 4 fps and 12 h with 2 fps with conventional two silver oxide 55-mA · h coin batteries. The tested localization accuracy shows less than sub-centimeter range.

Design of Reliable Body Channel Communication Transceiver with Spread Spectrum Clock Generator and PNR Generator

In this work, the communication of a channel in the human body has a characteristic (time-domain) which can be measured at various distances in transmission and various frequencies of a signal by the printed circuit board-an analog frontend board (PCB-AFE) support. Besides, for the wideband signal of Body Channel Communication (BCC), a human body skin acts within a range of 1 Mb/s to 40 Mb/s as the transmission medium. This communication is more stable and attenuating low power while comparing with all another transmission medium in wireless. Moreover, due to the motion of a human body, this communication doesn't get affected. Though, the body antenna gives effects in the communication of a channel of the human body by occurs some interference. The Manchester data acts as encoder and decoder in transmitter and receiver parts respectively, in an AFE-PCB the Manchester encoder data is amplified after receiving the data from end to end channel of a human body. The data quality is improved by 7X sampler in clock data recovery (CDR) circuit. Therefore, the proposed design of reliable BCC Transceiver with SSCG and PNR Generator is processed in XilinxISE14.5, ModelSim Simulator 6.5a (Quartus II 8.1), and Micro wind software tools. It is also implemented in a XilinxXC9572XL kit. The power consumption and delay is reduced up to 90%, speed is increased up to 50% and leakage current is reduced up to 80% in the transmitter part.

Integrated All Electrical Pulse Wave Velocity and Respiration Sensors Using Bio-Impedance

In this paper, we propose wire-free integrated sensors that monitor pulse wave velocity (PWV) and respiration, both non-electrical vital signs, by using an all-electrical method. The key techniques that we employ to obtain all-electrical and wire-free measurement are bio-impedance (BI) and analog-modulated body-channel communication (BCC), respectively. For PWV, time difference between ECG signal from the heart and BI signal from the wrist is measured. To remove wires and avoid sampling rate mismatch between ECG and BI sensors, ECG signal is sent to the BI sensor via analog BCC without any sampling. For respiration measurement, BI sensor is located at the abdomen to detect volume change during inhalation and exhalation. A prototype chip fabricated in 0.11 μm CMOS process consists of ECG, BI sensor and BCC transceiver. Measurement results show that heart rate and PWV are both within their normal physiological range. The chip consumes 1.28 mW at 1.2 V supply while occupying 5 mm×2.5 mm of area.