1. A reconfigurable antenna comprising two or more mutually coupled radiating elements and two or more impedance-matching circuits configured for independent tuning of the frequency band of each radiating element; and wherein each radiating element is arranged for selective operation in each of the following states: a driven state, a floating state and a ground state; the antenna being provided on a substrate having a ground plane printed on a first side thereof, a first of the radiating elements on a second side of the substrate, opposite the first side thereof, and laterally spaced from the ground plane; and a second of the radiating elements constituted by a planar microstrip patch, orthogonal to the ground plane.
2. The antenna according to claim 1 wherein at least one of the radiating elements is constituted by a non-resonant resonator.
3. The antenna according to claim 2 wherein two non-resonant resonators are employed.
4. The antenna according to claim 1 wherein each radiating element is configured to operate over a wideband andor a narrowband range of frequencies.
5. The antenna according to claim 1 wherein each impedance-matching circuit comprises a wideband tuning circuit and a narrowband tuning circuit.
6. The antenna according to claim 1, wherein the first radiating element is constituted by an L-shaped microstrip patch, having a planar portion and a portion orthogonal to the ground plane.
7. The antenna according to claim 6 wherein the orthogonal portion extends from an edge of the planar portion furthest from the ground plane such that the orthogonal portion is spaced from the ground plane by a so-called first gap.
8. The antenna according to claim 1, wherein the second radiating element is located between the ground plane and the orthogonal portion of the first radiating element.
9. The antenna according to claim 1, wherein each radiating element has an associated feed port.
10. The antenna according to claim 9 wherein each feed port is connected to a control module comprising a control means for selecting the operating state of the associated radiating element.
11. The antenna according to claim 10 wherein the control means comprises a switch selectively configured to allow the radiating element to float, to be connected to the ground plane or to be driven by its associated impedance-matching circuit.
12. The antenna according to claim 11 wherein a first feed port is provided between the first radiating element and a first control module having a first impedance-matching circuit and a second feed port is provided between the second radiating element and a second control module having a second impedance-matching circuit.
13. The antenna according to claim 12 wherein the first feed port is positioned closer to one side of the radiating element than the other.
14. The antenna according to claim 12 wherein the first feed port is connected to the ground plane along an edge thereof.
15. The antenna according to claim 12 wherein the first feed port is connected to the ground plane at or towards one side thereof.
16. The antenna according to claim 12 wherein the second feed port is placed in close proximity to the first feed port.
17. The antenna according to claim 1 wherein a single tuning capacitor is provided to tune each radiating element in each operating mode.
18. A portable electronic device comprising a reconfigurable antenna according to claim 1.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A mass sensor comprising:
a sensor substrate;
at least one connection plate extending along a first direction and having a first end attached to a first portion of said sensor substrate and an opposed second end;
at least one diaphragm attached to said second end of said connection plate;
means for changing the mass of said diaphragm, said means being positioned on said diaphragm;
at least one sensing plate having a first end attached to a second portion of said sensor substrate and an opposed second end attached to said diaphragm; and
at least one piezoelectric element arranged on at least a portion of a surface of said sensing plate;
wherein said sensing plate and said sensor substrate are arranged in substantially parallel planar relationship with respect to one another and wherein said at least one connection plate, said at least one diaphragm, said at least one sensing plate and said at least one piezoelectric element define a resonance portion.
2. The mass sensor according to claim 1, wherein said diaphragm, said connection plate, and said sensing plate are arranged in a substantially parallel coplanar relationship with respect to one another.
3. The mass sensor according to claim 1, wherein said diaphragm, said connection plate, and said sensing plate are integrally formed from an oscillation plate, and said sensor substrate is integrally laminated with said oscillation plate and a base plate.
4. The mass sensor according to claim 1, wherein said means for changing the mass of said diaphragm comprises a catching substance which reacts only with a substance to be sensed and catches the substance to be sensed, said catching substance being applied on at least a portion of said diaphragm;
wherein said piezoelectric element measures a resonant frequency of said resonance portion before the substance to be sensed has been caught by said catching substance and after the substance to be sensed has been caught by said catching substance; and
wherein a mass of the substance to be sensed, which is caught by said catching substance, is determined by measuring a change in the resonant frequency of said resonance portion.
5. The mass sensor according to claim 4, further comprising at least two resonance portions, wherein at least one of said resonance portions does not include said catching substance.
6. The mass sensor according to claim 4, further comprising at least two resonance portions each including a diaphragm, wherein a second catching substance is applied to at least a portion of at least one of said diaphragms of said resonance portions, said second catching substance being different from said catching substance.
7. The mass sensor according to claim 1, wherein a through-hole is formed in said sensor substrate, and said resonance portion is formed on an internal circumferential surface of said through-hole.
8. The mass sensor according to claim 1, wherein said at least one piezoelectric element comprises a first piezoelectric element for driving, and a second piezoelectric element for sensing.
9. The mass sensor according to claim 1, wherein said piezoelectric element includes at least one piezoelectric film comprising a material containing a main component of lead zirconate, lead titanate, and lead magnesium niobate.
10. The mass sensor according to claim 1, wherein said piezoelectric element includes an electrode that is laser-processed or machined to adjust an effective electrode area of said piezoelectric element.
11. A mass sensor, comprising:
a sensor substrate;
at least one diaphragm;
means for changing the mass of said diaphragm, said means being positioned on said diaphragm;
at least one connection plate joined at one end thereof to said sensor substrate and at another end thereof to said diaphragm;
at least one sensing plate arranged in parallel with said connection plate, and being joined at one end thereof to said sensor substrate and at another end thereof to said diaphragm; and
at least one piezoelectric element arranged on at least a portion of a surface of said sensing plate;
wherein said at least one connection plate, said at least one diaphragm, said at least one sensing plate and said at least one piezoelectric element define a resonance portion.
12. The mass sensor according to claim 1, further comprising at least two resonance portions, wherein a dynamic range is expanded by integrating respective signals from said resonance portions.
13. The mass sensor according to claim 1, wherein said at least one piezoelectric element comprises a first portion for driving and a second portion for sensing.
14. The mass sensor according to claim 1, further comprising a position sensor including a pair of electrodes centrally provided between said diaphragm and said piezoelectric element on said sensor substrate.
15. The mass sensor according to claim 1, further comprising electrode leads connected to said piezoelectric element, wherein an electrode of said piezoelectric element is coated with a resin or a glass insulation layer.
16. The mass sensor according to claim 15, wherein said resin comprises a fluorine resin or a silicone resin.
17. The mass sensor according to claim 15, further comprising a shield layer including a conductive material formed on a surface of said insulation layer.