Antenna assembly detection based on oscillator and variable reactance tank circuit

1. A device comprising:

a memory that stores comparison data;

a radio frequency (RF) communication interface;

an antenna terminal configured to connect to an external antenna;

an oscillator circuit whose frequency of operation is determined by a resonant frequency of a tank circuit and reactance of a load associated with the antenna terminal; and

a controller configured to:

measure an output signal of the oscillator circuit when the oscillator circuit is connected to the antenna terminal;

normalize a frequency of the output signal based on an open-circuit frequency of the oscillator circuit; and

determine whether or not the external antenna is connected to the antenna terminal based on the measurement and the comparison data, wherein the device is a meter interface unit.

2. The device of claim 1 , wherein the comparison data includes a first frequency value indicating that the external antenna is connected to the antenna terminal, and a second frequency value indicating that the external antenna is not connected to the antenna terminal.

3. The device of claim 1 , wherein the oscillator circuit includes an inductor capacitor (LC) oscillator.

4. The device of claim 1 , wherein the external antenna includes an intermediary connector.

5. The device of claim 1 , wherein the controller is further configured to:

transmit data, via an internal antenna of the device, in response to a determination that the external antenna is not connected to the antenna terminal.

6. The device of claim 1 , wherein the comparison data includes frequency values pertaining to different types of external antennas.

7. The device of claim 1 , further comprising:

an internal antenna; and

a switch, wherein the switch can selectively switch between a first connection with the oscillator circuit and the antenna terminal and a second connection with the RF communication interface and the antenna terminal.

8. The device of claim 1 , wherein the controller is further configured to:

detect a triggering event; and

measure the output signal in response to the detection of the triggering event.

9. The device of claim 1 , wherein the comparison data includes a frequency value indicating that the external antenna is connected to the antenna terminal but is damaged.

10. The device of claim 1 , wherein the controller is further configured to:

transmit data, via the radio communication interface and the external antenna, in response to a determination that the external antenna is connected to the antenna terminal.

11. A non-transitory computer-readable storage medium storing instructions executable by a processor of a device, which when executed cause the device to:

measure an output signal of an oscillator circuit when the oscillator circuit is connected to an antenna terminal, wherein the oscillator circuit has a frequency of operation determined by a resonant frequency of a tank circuit and reactance of a load associated with the antenna terminal, and wherein the antenna terminal is configured to connect to an external antenna;

normalize a frequency of the output signal based on an open-circuit frequency of the oscillator circuit; and

determine whether or not the external antenna is connected to the antenna terminal based on the measurement and stored comparison data, wherein the device is a meter interface unit.

12. The non-transitory computer-readable storage medium of claim 11 , wherein the comparison data includes a first frequency value indicating that the external antenna is connected to the antenna terminal, and a second frequency value indicating that the external antenna is not connected to the antenna terminal.

13. The non-transitory, computer-readable storage medium of claim 11 , wherein the instructions further comprise instructions, which when executed cause the device to:

transmit data, via a radio communication interface of the device and the external antenna, in response to a determination that the external antenna is connected to the antenna terminal.

14. The non-transitory computer-readable storage medium of claim 11 , wherein the external antenna includes an intermediary connector.

15. The non-transitory, computer-readable storage medium of claim 11 , wherein the instructions further comprise instructions, which when executed cause the device to:

transmit data, via an internal antenna of the device, in response to a determination that the external antenna is not connected to the antenna terminal.

16. A method comprising:

measuring, by a device, an output signal of an oscillator circuit of the device when the oscillator circuit is connected to an antenna terminal of the device, wherein the oscillator circuit has a frequency of operation determined by a resonant frequency of a tank circuit and reactance of a load associated with the antenna terminal, and wherein the antenna terminal is configured to connect to an external antenna;

normalizing, by the device, a frequency of the output signal based on an open-circuit frequency of the oscillator circuit; and

determining, by the device, whether or not the external antenna is connected to the antenna terminal based on the measurement and stored comparison data, wherein the device is a meter interface unit.

17. The method of claim 16 , wherein the data includes a first frequency value indicating that the external antenna is connected to the antenna terminal, and a second frequency value indicating that the external antenna is not connected to the antenna terminal.

18. The method of claim 16 , further comprising:

transmitting, via a radio communication interface of the device and the external antenna, data in response to determining that the external antenna is connected to the antenna terminal.

19. The method of claim 16 , wherein the external antenna includes an intermediary connector.

20. The method of claim 16 , further comprising:

transmitting data, via an internal antenna, in response to determining that the external antenna is not connected to the antenna terminal.