SPEAKER WITH COIL ANTENNA
A speaker is provided in which both audio signals and radio frequency (RF) signals are simultaneously fed to the coil of a speaker device causing the coil to drive the speaker's membrane producing sound and operate as an antenna for various electromagnetic frequencies. The speaker can be equipped with appropriate filter circuits to isolate the audio signals and RF signals within the speaker device.
1 . A speaker device comprising:
a yoke;
a magnet disposed within the yoke;
a top plate disposed on one side of the magnet;
a coil surrounding the magnet, the coil configured for movement in a space between the yoke and the magnet;
a membrane connected to the coil;
a plurality of coil leads connected to the coil;
an audio circuit connected to the coil through the coil leads; and
a radio frequency (RF) circuit connected to the coil through the coil leads,
wherein the audio circuit generates audio signals that are delivered to the coil for the production of sound and the RF circuit generates RF signals that are delivered to the coil for the production of electromagnetic signals, the audio signals and RF signals being delivered to the coil simultaneously.
2 . The speaker device of claim 1 , further comprising a low pass filter connected between the audio circuit and the coil.
3 . The speaker device of claim 1 , further comprising a high pass filter connected between the RF circuit and the coil.
4 . The speaker device of claim 1 wherein the RF circuit is further configured to receive external RF signals received by the coil.
5 . The speaker device of claim 1 wherein the plurality of coil leads comprises a first coil lead and a second coil lead, wherein the first coil lead being connected to the audio signal from the audio circuit and to an RF feed from the RF circuit and wherein the second coil lead is connected to the audio signal from the audio circuit and to an RF ground of the RF circuit.
6 . The speaker device of claim 5 further comprising at least two impedance matching circuits connected between the RF feed from the RF circuit and the first coil lead and at least one switch configured to switch between the at least two impedance matching circuits.
7 . The speaker device of claim 1 , further comprising a dielectric material located in proximity to the coil and configured to alter the frequencies at which the coil effectively radiates electromagnetic waves.