Battery antenna for smart label
Techniques are provided for reducing the form factor of smart labels. An example smart label includes a flexible circuit board comprising two or more layers, a communications circuit including at least one transceiver disposed on one of the two or more layers, an antenna tuning circuit disposed on one of the two or more layers and configured to receive radio frequency signals from the communications circuit, at least one flexible battery disposed on a first layer of the two or more layers and configured to provide power to the communications circuit, and an antenna element disposed on a second layer of the two or more layers and proximate to the at least one flexible battery, wherein the antenna element is configured to receive the radio frequency signals from the antenna tuning circuit.
1. A smart label, comprising:
a flexible circuit board;
a communications circuit including at least one transceiver disposed on the flexible circuit board;
an antenna tuning circuit disposed on the flexible circuit board and configured to receive radio frequency signals from the communications circuit; and
at least one flexible battery disposed on the flexible circuit board and configured to provide power to the communications circuit and receive the radio frequency signals from the antenna tuning circuit.
2. The smart label of claim 1 , further comprising one or more radio frequency decoupling circuits disposed between the at least one flexible battery and the communications circuit.
3. The smart label of claim 1 , wherein the at least one flexible battery is configured to receive the radio frequency signals via a positive terminal.
4. The smart label of claim 1 , wherein the antenna tuning circuit includes one or more variable capacitors configured to vary an impedance of the antenna tuning circuit.
5. The smart label of claim 4 , wherein the communications circuit is configured to provide a control signal to the antenna tuning circuit to set a capacitance value of the one or more variable capacitors.
6. The smart label of claim 1 , wherein the communications circuit is configured to communicate via a wireless wide area network (WWAN).
7. The smart label of claim 1 , wherein the communications circuit is configured to communicate via a wireless local area network (WLAN).
8. The smart label of claim 1 , wherein the radio frequency signals are within a range from 700 MHz to 2.2 GHz.
9. The smart label of claim 1 , wherein the communications circuit is configured to receive external radio frequency signals via the at least one flexible battery.
10. A smart label, comprising:
a flexible circuit board comprising two or more layers;
a communications circuit including at least one transceiver disposed on one of the two or more layers;
an antenna tuning circuit disposed on one of the two or more layers and configured to receive radio frequency signals from the communications circuit;
at least one flexible battery disposed on a first layer of the two or more layers and configured to provide power to the communications circuit; and
an antenna element disposed on a second layer of the two or more layers and proximate to the at least one flexible battery, wherein the antenna element is configured to receive the radio frequency signals from the antenna tuning circuit.
11. The smart label of claim 10 , wherein the antenna element is electromagnetically coupled to the at least one flexible battery.
12. The smart label of claim 10 , wherein the antenna element is configured as a monopole antenna, an inverted F type antenna, a slot antenna, or a loop antenna.
13. The smart label of claim 10 , further comprising one or more radio frequency decoupling circuits disposed between the at least one flexible battery and the communications circuit.
14. The smart label of claim 10 , wherein the antenna tuning circuit includes one or more variable capacitors configured to vary an impedance of the antenna tuning circuit.
15. The smart label of claim 14 , wherein the communications circuit is configured to provide a control signal to the antenna tuning circuit to set a capacitance value of the one or more variable capacitors.
16. The smart label of claim 10 , wherein the communications circuit is configured to communicate via a wireless wide area network (WWAN) or via a wireless local area network (WLAN).
17. The smart label of claim 10 , wherein the radio frequency signals are within a range from 700 MHz to 2.2 GHz.
18. The smart label of claim 10 , wherein the communications circuit is configured to receive external radio frequency signals via the antenna element.
19. The smart label of claim 10 , further comprising:
a rectifier circuit disposed on one of the two or more layers; and
a power management circuit disposed on one of the two or more layers and configured to receive a direct current signal from the rectifier circuit, wherein the direct current signal is obtained from external radio frequency signals received by the antenna element.
20. The smart label of claim 10 , wherein there is a geometric overlap between the at least one flexible battery disposed on the first layer and the antenna element disposed on the second layer.