Constant phase
Various embodiments are described that relate to a loop with a constant phase. The loop can function as an antenna and be used in object detection. A current source can be used to power the loop such that the loop produces a magnetic field and an electric field. The magnetic field can be powerful enough to detect a dielectric while the electric field is so small that it does not interfere with nearby communication equipment. Thus, detection can occur without disruption of other important devices.
1. A singular loop antenna, comprising:
a first wire section;
a second wire section that is distinct from the first wire section;
a third wire section that is distinct from the first wire section and distinct from the second wire section, where the first wire section and the third wire section are not contiguous;
a first reactive compensation element that divides the first wire section from the second wire section; and
a second reactive compensation element that divides the second wire section from the third wire section and that is distinct from the first reactive compensation element,
where the first wire section, the second wire section, the third wire section, the first reactive compensation element, and the second reactive compensation element form at least part of a loop powered by a current of at least two amps supplied from a low impedance current source,
where the singular loop antenna, when supplied with the current, produces a magnetic field that is substantially greater than an electric field along a longitudinal axis of the singular loop antenna,
where the first reactive compensation element offsets an impedance of the first wire section,
where the second reactive compensation element offsets an impedance of the second wire section,
where a magnitude is kept substantially constant throughout the loop such that a magnitude change is not greater than that which is produced by no more than one of the wire sections, and
where a phase is kept substantially constant throughout the loop such that a phase change is not greater than that which is produced by no more than one of the wire sections.
2. The singular loop antenna of claim 1 , where the magnetic field extends about one wavelength from the loop, where a frequency of the singular loop antenna is between about 1 Megahertz to about 1 Gigahertz, where the singular loop antenna performs transmission and reception functions, and where the singular loop antenna is a singular small loop antenna.
3. The singular loop antenna of claim 2 , where the magnetic field is of a sufficient strength to detect a metal, where the first reactive compensation element has a value that causes the electric field to be minimized, where the second reactive compensation element has a value that causes the electric field to be minimized, and where the electric field is low enough as to not substantially impact a communication device.
4. The singular loop antenna of claim 3 , where characteristics of the loop are altered in a binary manner such that direct current is produced and where the direct current powers an active circuit wirelessly.
5. A singular loop antenna, comprising:
a first wire section;
a second wire section that is distinct from the first wire section;
a third wire section that is distinct from the first wire section and distinct from the second wire section, where the first wire section and the third wire section are not contiguous;
a first reactive compensation element that divides the first wire section from the second wire section; and
a second reactive compensation element that divides the second wire section from the third wire section and that is distinct from the first reactive compensation element,
where the first wire section, the second wire section, the third wire section, the first reactive compensation element, and the second reactive compensation element form at least part of a loop powered by a current of at least two amps supplied from a low impedance current source,
where the singular loop antenna, when supplied with the current, produces a magnetic field and an electric field,
where the magnetic field is substantially greater than the electric field along a longitudinal axis of the singular loop antenna,
where the first reactive compensation element offsets an impedance of the first wire section,
where the second reactive compensation element offsets an impedance of the second wire section,
where a magnitude is kept substantially constant throughout the loop such that the magnitude change is not greater than that which is produced by no more than one of the wire sections,
where a phase is kept substantially constant throughout the loop such that the phase change is not greater than that which is produced by no more than one of the wire sections, and
where a frequency of the singular loop antenna is between about 1 Megahertz to about 1 Gigahertz.
6. The singular loop antenna of claim 5 , where the magnetic field extends about one wavelength from the loop.
7. The singular loop antenna of claim 5 , where the singular loop antenna performs transmission and reception functions.
8. The singular loop antenna of claim 5 , where the singular loop antenna is a singular small loop antenna.
9. The singular loop antenna of claim 5 , where the magnetic field is of a sufficient strength to detect a dielectric.
10. The singular loop antenna of claim 5 , where the magnetic field is of a sufficient strength to detect a metal.
11. The singular loop antenna of claim 5 , where the first reactive compensation element has a value that causes the electric field to be minimized.
12. The singular loop antenna of claim 5 , where the second reactive compensation element has a value that causes the electric field to be minimized.
13. The singular loop antenna of claim 5 , where the electric field is low enough as to not substantially impact a communication device.
14. The singular loop antenna of claim 5 , where characteristics of the loop are altered in a binary manner such that a direct current is produced.
15. The singular loop antenna of claim 14 , where the direct current powers an active circuit wirelessly.
16. A singular small loop antenna operating at less than about one-quarter of a wavelength, comprising:
a first wire section;
a second wire section that is distinct from the first wire section;
a third wire section that is distinct from the first wire section and distinct from the second wire section, where the first wire section and the third wire section are not contiguous;
a first reactive compensation element that divides the first wire section from the second wire section; and
a second reactive compensation element that divides the second wire section from the third wire section and that is distinct from the first reactive compensation element,
where the first wire section, the second wire section, the third wire section, the first reactive compensation element, and the second reactive compensation element form at least part of a loop powered by a current of at least two amps supplied from a low impedance current source,
where the singular small loop antenna, when supplied with the current, produces a magnetic field that is substantially greater than an electric field along a longitudinal axis of the singular small loop antenna,
where the first reactive compensation element offsets an impedance of the first wire section,
where the second reactive compensation element offsets an impedance of the second wire section,
where a magnitude is kept substantially constant throughout the loop such that the magnitude change is not greater than that which is produced by no more than one of the wire sections,
where a phase is kept substantially constant throughout the loop such that the phase change is not greater than that which is produced by no more than one of the wire sections.
17. The singular small loop antenna of claim 16 ,
where the first reactive compensation element has a value that causes the electric field to be minimized,
where the second reactive compensation element has a value that causes the electric field to be minimized, and
where the singular small loop antenna performs transmission and reception functions.
18. The singular small loop antenna of claim 17 ,
where the magnetic field extends about one wavelength from the loop, where a frequency of the singular small loop antenna is between about 1 Megahertz to about 1 Gigahertz,
where characteristics of the loop are altered in a binary manner such that direct current is produced, and
where the direct current powers an active circuit wirelessly.
19. The singular small loop antenna of claim 17 ,
where the magnetic field is of a sufficient strength to detect a metal and
where the electric field is low enough as to not substantially impact a communication device.
20. The singular small loop antenna of claim 17 ,
where the magnetic field is of a sufficient strength to detect a dielectric and
where the electric field is low enough as to not substantially impact a communication device.