19-03-2012, 11:06 AM
RED TACTON
CHAPTER 1
INTRODUCTION
We may have imagined the feature as a place crawling with antennas and emitters, due to the huge growth of wireless communications. And it is seems that the current means of transferring data might already have a very serious competitor none other than the human body.
Thus NTT labs from Japan has announced that is currently testing a revolutionary technology called “ red tacton ”,which use the electric fields generated by the human body as medium for transmitting the data . The chips which will embedded in various devices contain a transmitter and receiver built to send and accept data in digital format. The chips can take any type of file such as mp3 music file or mail and convert it in to the format that takes the form of digitals pulse that can be passed and read through a human being electric field .The chip in receiver devices reads these tiny changes and convert the file back into its original for
Human Area Networking (HAN) is a technology that safely turns the surface of the human body into a data transmission path at speeds up to 10 Mbps between any two points on the body.
1.1 History of HAN
• The concept of intra-body communication was first proposed by IBM in 1996.
• This communication mechanism was later evaluated and reported by several research groups around the world.
All those reported technologies had two limitations.
1. The operating range through the body was limited to a few tens of centimeters.
2. The top communication speed was only 40 bit/s!!
These limitations were overcome by NTT (Nippon Telegraph and Telephone
Corporation) located in Tokyo, Japan by using photonic electric field sensors
and finally came up with a human area networking technology called
‘REDTACTON’
. 1.2 Overview of HAN
• RedTacton is a new Human Area Networking technology that turns the surface of the human body as a safe, high speed network transmission path.
• Communication is possible using any body surfaces, such as the hands, fingers, arms, feet, face, legs or toes.
• RedTacton works through shoes and clothing as well.
• RedTacton uses the minute electric field emitted on the surface of the human body for data transmission.
NTT developed super sensitive Photonic electric field sensor for detecting minute electric field emitted on the surface of the human body.
The electro-optic sensor has three key features:
It can measure electric fields from a device under test (DUT) without contacting it, which minimizes measurement disturbance.
Ultra wide-band measurement is possible.
It supports one-point contact measurement that is independent of the ground,
Which is the most significant feature in the present context.
NTT utilized this third feature to fabricate an intrabody communication receiver
For its human area networking technology, which is called RedTacton.
1.3 Human Area Networking
NTT has had excellent success with an electro-optic sensor combining an electrooptic crystal with laser light and recently reported an application of this sensor for measuring high-frequency electronic devices [2], [3]. The electro-optic sensor has three key features:
(1) it can measure electric fields from a device under test (DUT) without contacting it, which minimizes measurement disturbance,
(2) ultrawide-band measurement is possible, and
(3) it supports one-point contact measurement that is independent of the ground, which is the most significant feature in the present context.
NTT utilized this third feature to fabricate an intrabody communication receiver for its human area networking technology, which is called RedTacton.
CHAPTER 2
NARRATION
2.1 What is RedTacton?
TACTON: - “touch-act-on” Meaning “action triggered by touching”.
RED: - It is an auspicious color according to Japanese culture
RedTacton transceiver
Red Tacton is a new Human Area Networking technology that uses the surface of the human body as a safe, high speed network transmission path. Red Tacton uses the minute electric field emitted on the surface of the human body. Technically, it is completely distinct from wireless and infrared .A transmission path is formed at the moment a part of the human body comes in contact with a Red Tacton transceiver. Physically separating ends the contact and thus ends communication Using Red Tacton, communication starts when terminals carried by the user or embedded in devices are linked in various combinations according to the user's Communication is possible using any body surfaces, such as the hands, fingers, arms, feet,face, legs or torso. Red Tacton works natural, physical movements.
• The transmitter consists of a transmitter circuit that induces electric fields toward the body and a data sense circuit, which distinguishes transmitting and receiving modes by detecting both transmission and reception data and outputs control signals corresponding to the two modes to enable two-way communication.
• Implementation of receive-first half-duplex communication scheme that sends only after checking to make sure that there is no data to receive in order to avoid packet collisions
• RedTacton takes advantage of the long-overlooked electric field that surrounds the human body.
2.2 How RedTacton works?
Using a new super-sensitive photonic electric field sensor, Red Tacton can achieve duplex communication over the human body at a maximum speed of 10 mbps
The Red Tacton transmitter induces a weak electric field on the surface of the
body. The Red Tacton receiver senses changes in the weak electric field on the surface of the body caused by the transmitter .Red tacton relies upon the principle that the optical properties of an electro-optic crystal can vary according to the changes of a weak electric field. Red Tacton detects changes in the optical properties of an electro-optic crystal using a laser and converts the result to an electrical signal in a optical receiver circuit. The transmitter sends data by inducing fluctuations in the minute electric field on the surface of the human body. Data is received using a photonic electric field sensor that combines an electro-optic crystal and a laser light to detect fluctuations in the minute electric field.
1. The RedTacton transmitter induces a weak electric field on the surface of the body.
2. The RedTacton receiver senses changes in the weak electric field on the surface of the body caused by the transmitter.
3. RedTacton relies upon the principle that the optical properties of an electro-optic crystal can vary according to the changes of a weak electric field.
4. RedTacton detects changes in the optical properties of an electro-optic crystal using a laser and converts the result to an electrical signal in a optical receiver circuit
Multiple transceivers can be used simultaneously. This is because RedTacton uses a proprietary CSMA/CD (Carrier Sense Multiple Access with Collision Detection) protocol that allows multiple access with the same medium from multiple nodes
2.3 Mechanism of communication with RedTacton
The naturally occurring electric field induced on the surface of the human body dissipates into the earth. Therefore, this electric field is exceptionally faint and unstable. The photonic electric field sensor developed by NTT enables weak electric fields to be measured by detecting changes in the optical properties of an electro-optic crystal with a laser beam.
The operating principle of RedTacton is illustrated in Fig. 2.5 The electric field induced toward the body transceivers. The experimental setup for intrabody communication assuming communication between two electronic devices (PDAs) is shown in Fig. . We prepared two sets of RedTacton transceivers, each connected to a PDA. The subject held one transmitting receiving electrode in each hand. We quantitatively measured the bit error rates of signals sent through the body. The results showed that the system had no significant practical problems at a transmission speed of 10 Mbit/s. Besides communication between two hands, we also demonstrated reliable communication between a foot and finger and between other locations on the person’s body. We also verified that good communication was achieved not only when the electrodes were in direct contact with the person’s skin ,but also when the signals passed through clothing and shoes.
2.4 RedTacton Transceiver
Figure 2.6 shows a photograph of the RedTacton transceiver connected to a PDA and a block diagram of the Red-Tacton transceiver [5] developed by NTT. The transmitter consists of a transmitter circuit that induces electric fields toward the body and a data sense circuit, which distinguishes transmitting and receiving modes by detecting both transmission and reception data
and outputs control signals corresponding to the two modes to enable two-way communication. We implemented a receive-first half-duplex communication scheme that sends only after checking to make sure that there is no data to receive in order to avoid packet collisions between terminals in compliance with the IEEE 802.3 protocol. The receiver consists of an electro-optic sensor and a detector circuit that amplifies the minute incoming signal from the electrooptic
sensor and converts it to electrical signal.
We conducted a series of trials in which data was sent through human bodies using RedTacton transceivers The experimental setup for intrabody communication assuming communication between two electronic devices (PDAs) is shown in Fig. 2.7 We prepared two sets of RedTacton transceivers, each connected to a PDA. The subject held one transmitting receiving electrode in each hand. We quantitatively measured the bit error rates of signals sent through the body. The results showed that the system had no significant practical problems at a transmission speed of 10 Mbit/s. Besides communication between two hands, we also demonstrated reliable communication between a foot and finger and between other locations on the person’s body. We also verified that good communication was achieved not only when the electrodes were in direct contact with the person’s skin, but also when the signals passed through clothing and shoes.
2.5 System Safety
We investigated the effects of RedTacton technology on human health, which is obviously an important issue. First, as shown in Fig. 2.4, the transmitting and receiving electrodes of the RedTacton transceiver are completely covered with insulating film, so the body of the person acting as the transmission medium is completely insulated. This makes it impossible for current to flow into a person’s body from the transceiver. When communication occurs, displacement current is generated by the electrons in the body because the body is subjected to minute electrical fields. However, such displacement currents are very common everyday occurrences to which we are all subjected.
RedTacton conforms to the “Radio Frequency-Exposure Protection Standard (RCR STD-38)” [6] issued by the Association of Radio Industries and Businesses (ARIB). The levels produced by RedTacton are well below the safety limit specified by this standard.
NO current flows into human body from red tacton devices. RedTacton uses the Electric field that occurs naturally on the surface of the human body for Communication. Transmitter and receiver electrodes are covered with an Insulating films.
RedTacton is in conformity to the "Radiofrequency-exposure Protection” standard
(RCR STD-38)" issued by the Association of Radio Industries and Businesses
(ARIB).
2.6 Prototype :-
NTT has made three types of prototypes
Communicationspeed:10Mbps
Protocols : TCP/IP
Communication method :Half-duplex
Interface: PCMCIA
Communicationspeed:10Mbps
Protocols :TCP/IP
Communication method : Half-duplex
Interface: RJ45
2.7 Plans for Commercialization
It seems like there was a press release event where they demoed the technology. The first demo was a PDA medication assistant that shows instructions relevant to touched medicine bottles. The second was a museum guide PDA whose contents was fed from a floor-embedded transmitter through a user’s feet.
NTT plans to develop transceivers with an emphasis on portability that are more compact and less power consumption. Through field testing, NTT will continue to investigate and improve the robustness of Human Area Networking and human body surface communication applications.