Technology dreamers envision a future in which individuals do not use access points, but instead function as their own communications hubs. Among the companies moving the world closer to that reality is Microchip Technology, Inc., which just unveiled its BodyCom technology. This technology gives designers a framework to use the human body as a secure communication channel. Compared to existing wireless methods, it promises to provide lower energy consumption while increasing security via bidirectional authentication. Because no RF antennas are required, BodyCom technology also allows for simple circuit-level designs and a low bill of materials (BOM).
At its heart, BodyCom technology is activated by capacitively coupling to the human body (see figure). The system then begins communicating bidirectionally between a centralized controller and one or more wireless units. By eliminating the need for a wireless transceiver or high-power inductive fields, BodyCom technology lengthens battery life.
In addition to eliminating the need for antennas, BodyCom simplifies development by using a low-frequency framework with a common microcontroller and standard active-front-end (AFE) frequencies (125 kHz and 8 MHz). Thus, no external reference crystals are needed. Because it complies with Federal Communications Commission (FCC) Part 15-B for radiated emissions, the technology also eliminates the cost and complexity of certification.
To keep this human-body-network secure, bidirectional authentication can be added. It supports advanced encryption, such as KeeLoq technology and Advanced Encryption Standards (AES). For example, BodyCom technology promises to help prevent the “Relay Attack” problem that is typical in automotive passive remote-keyless-entry (RKE) security systems. Example applications for this technology include access control (security systems, home/industrial door locks, pet doors); personal safety and security (equipment access/disable, power tools, firearms, computer systems); medical (patient monitoring, hospital-room access, equipment tracking); and consumer (profile management for gaming consoles and exercise equipment).
Key to this technology’s purported ease of use is the BodyCom Development V1.0 Framework. That framework includes a communication library, application code examples, and a development graphical user interface (GUI) for use on personal computers. It is supplied through free software libraries, which work on all of Microchip’s 8-, 16-, and 32-b PIC microcontrollers. In addition, the BodyCom Development Kit, which comes with a central controller unit and two wireless mobile units, is available for $149.
