Here are the frequently asked questions related to the proposed technology.
A. There is no battery being used in the device.
The unique feature of the proposed technology is that both power and data are transmitted through a human body. Therefore, an electric field human body communication introduced here can be called a passive electric field NFC system that is kind of similar to a passive RFID. Unlike a conventional RFID system though, our design utilizes a lossy human body as a transmission medium between communication devices.
A. No, you can’t communicate.
With intuitive and easy operation which securely reflects the intention of users, our design puts the value on the concept of “Disable communication when not needed” as well as “Enable communication when you want to”.“Able to communicate at the distance” can be realized by a conventional wireless communication (Bluetooth, Wi-Fi, etc.). Our design disables the communication at a distance more than a few millimeters from the body. This function prevents the unintended communication to occur.
A. No, it should not.
Signals transmit with a capacitive coupling, where a capacitor is formed between communication device and a human body. Since the electric field signal is rapidly attenuating away from the human body, the device is better be placed as close as possible for more stable communication. If there is a dielectric layer between them, it is possible to transmit a signal along it. With the antenna being embedded at one side of the wrist-band and the other side of the band adhering to skin, or with the electric field antenna integrated in the floor and operating with the shoes sole, we can communicate.
A. No, it is supposed to be safe.
According to the safety standards (electric field defense guideline) by the Ministry of Internal Affairs and Communications of Japan and by the IEC, absorption effect (SAR: Specific Absorption Rate) is specified at the 13.56MHz frequency band of the NFC. Compared with the tolerance SAR value of 2W/kg averaged over 10 gr of tissue during 6 minutes (4W/kg for the limbs), small transmission output of the NFC reader and a short-period communication are considered not to influence the human body.
A. No, there is no signal processing inherent in the electric field NFC being used whatsoever.
The antenna used for the communication can be called a hybrid antenna as it converts the magnetic field into the electric field and back. The main part of the communication system uses the existing NFC module as it is. As a result of this, no additional response time or data rate degradation will occur. With our electric field antenna, we can help you to provide user-friendly services by using NFC IC chip with high reliability and low cost.
A. A new mechanism to prevent unintended communication has been introduced.
In the issue of intuitive communication with those touched by a human body, i.e. the so-called “human body communication technology”, a possibility that the data may get read unintentionally by a person approaching in a crowded train or public place has been pointed out. By not allowing communication with touching everywhere on the body but controlling/limiting the body parts being able to communicate, this dedicated method securely prevents such an unintentional communication.
A. Frequency band is 13.56MHz. Transmission rate can vary as 26kbps, 106kbps, 212kbps or 424kbps.
What we provide is the technology altering the path of a communication signal. The communication itself is performed with the existing IC chip and communication module, therefore the carrier frequency, modulation method and transmission rate depend on the specification of the chip being used and are not limited to the conventional NFC. In other words, the proposed eNFC does not stipulate the communication protocol so that you can freely choose and use a standard in accordance with your practical needs (FeliCa, Type-A, Type-B, ISO15693, etc).
A. We aim for the practical system application by the end of 2017.
Realization requires not only “the communication technology” but also a new service and useful app being introduced with it. In order to implement the service sooner, we have been working in the collaboration with the partners outside the company.