System and portable device for transmitting identification signals
A system is provided with a portable device ( 31 ) for the transmission of signals to a second device, wherein the portable device ( 31 ) is wearable on the body of a user. The portable device ( 31 ) includes at least two electrodes ( 3, 4 ) and transmitter electronics ( 7 ) for applying an electrical signal between the electrodes, in such a way that the signal between the electrodes ( 3, 4 ) is able to be coupled into the body of the user and detected by at least one electrode of the second device. The transmitter electronics are an application specific integrated circuit and thus include both means for the production of electrical signals that are dependent upon specified data, as well as means for applying the electrical signal between the electrodes. The means for generating electrical signals that are dependent upon specified data are typically digital circuits for the encoding of specified data that are to be transmitted and for the modulation of the data that are so encoded.
1. A portable device for transmitting signals to a second device to transmit data from the portable device to the second device, wherein the portable device is wearable by a user, the device comprising: at least two electrodes and
an output driver for applying an electrical signal between the electrodes such that the signal is able to be coupled into the body of the user by the electrodes and detected by at least one electrode of the second device,
wherein the portable device is capable of transmitting identification information,
wherein the mentioned output driver for applying the electrical signal between the electrodes is a part of transmitter electronics, which transmitter electronics is capable of generating the electrical signal dependent upon specified data, and wherein the transmitter electronics are implemented as an application-specific integrated circuit (ASIC), the application specific integrated circuit comprising:
a modulator for generating an electrical signal dependent upon specified data and
the output driver for applying the electrical signal between the electrodes,
the application-specific integrated circuit being designed for the end of communicating to the second device a signal concerning a battery charge level of a feed of the integrated circuit.
2. The portable device according to claim 1 , wherein the integrated circuit further comprises:
an encoder for encoding the data to be transmitted and therewith for generating encoded data,
a modulator for modulating the encoded data and therewith for generating a modulated signal, and
a driver for amplifying the modulated signal and for driving the electrodes.
3. The portable device according to claim 1 , wherein the integrated circuit further comprises a communications interface to further electronic component parts of the portable device.
4. The portable device according to claim 3 , wherein the communications interface is an I2C interface.
5. The portable device according to claim 1 , being designed to use a spread spectrum method for data transmission, wherein the signal is transmitted as an ultra-broadband signal.
6. The portable device according to claim 5 , in which the range of a “chip” used for modulation in the spread spectrum method is selectable.
7. The portable device according to claim 1 , in which a carrier frequency is selectable.
8. The portable device according to claim 1 , in which the specified data are stored in a non-volatile memory of the integrated circuit.
9. The portable device according to claim 8 , wherein the memory is an EEPROM memory.
10. The portable device according claim 1 , in which the specified data are transmittable according to the following transmission mode:
repeat transmission of the same set of the specified data, wherein this set of the specified data is stored in a non-volatile memory of the integrated circuit.
11. The portable device according to claim 1 , comprising a circuit for detecting at least one battery state of a feed of the integrated circuit and for adjusting an operating condition of the integrated circuit according to the battery state.
12. The portable device according to claim 1 , further comprising a “low comfort mode” in which the transmitter electronics are inactive by default and must be actively activated, for example by pressing a button.
13. The portable device according to claim 1 , further comprising an interface to an activity detector, whereby a sending-out of the signal is stopped, as soon as the portable device is not moved for a specified time, and the sending-out of the signal is resumed again if the portable device is moved.
14. The portable device according to claim 1 , further comprising a charge recovery logic or an adiabatic switching logic for controlling the electrodes.
15. The portable device according to claim 1 , further comprising at least two different output drivers for energizing the electrodes and a control logic for selecting one of the output drivers according to the requirements of the type of electrodes used.
16. The portable device according to claim 1 , in which a signal bandwidth is selectable.
17. The portable device according claim 1 , in which the specified data are transmittable according to the following transmission mode:
repeat transmission of the same set of the specified data, wherein this set of the specified data is able to be altered over a communications interface of the integrated circuit.
18. The portable device according claim 1 , in which the specified data are transmittable according to the following transmission mode:
transmission of variable sets of the specified data, wherein these sets of specified data are able to be specified over the communications interface of the integrated circuit.