1. A dipole, comprising:
a feed line electrically coupled to a first antenna element;
a balun electrically coupled to a second antenna element; and
a short assembly slidably coupled to the feed line and the balun to create a short circuit at variable distances along the feed line and the balun.
2. The dipole according to claim 1, further comprising:
a support plate holding the feed line and the balun at a fixed spacing, the support plate including a short circuit path between the feed line and the balun.
3. The dipole according to claim 1, wherein the short assembly is detachably coupled to the feed line and the balun.
4. The dipole according to claim 1, wherein each of the variable distances along the feed line and the balun correspond to a receiving frequency band.
5. The dipole according to claim 4, wherein the receiving frequency band is one of an Advanced Mobile Phone System frequency band, a Global System for Mobile Communication frequency band, a Digital Cellular System frequency band, a Personal Communication Services frequency band, and an Industrial, Scientific and Medical frequency band.
6. The dipole according to claim 1, wherein at least one of the first and second antenna elements includes a plurality of releaseably connectable conducting segments.
7. The dipole according to claim 6, wherein each of the segments is an aluminum hexagonal standoff having a length of substantially one inch.
8. The dipole according to claim 1, wherein the first and second antenna elements are constructed from a conducting material including one of aluminum, brass and copper.
9. The dipole according to claim 1, wherein the feed line is one of a semi-rigid coaxial cable and a rigid coaxial cable.
10. The dipole according to claim 1, wherein the short assembly includes a switch.
11. The dipole according to claim 1, further comprising:
a spacer holding the feed line and the balun at the fixed spacing.
12. A dipole, comprising:
a variable length antenna element;
a feed line coupled to the variable length antenna element;
a balun; and
a switch assembly slidably coupled to the feed line and the balun,
wherein, when the switch assembly is closed, the switch assembly creates a short circuits at variable distances along the feed line and the balun.
13. The dipole according to claim 12, further comprising:
a support plate holding the feed line and the balun at a fixed spacing and creating a permanent short circuit between the feed line and the balun.
14. The dipole according to claim 12, wherein a first variable distance corresponds to one of an Advanced Mobile Phone System frequency band and a Global System for Mobile Communication frequency band, a second variable distance corresponds to one of a Digital Cellular System frequency band and a Personal Communication Services frequency band, and a third variable distance corresponds to an Industrial, Scientific and Medical frequency band.
15. The dipole according to claim 12, wherein the variable length antenna element includes a plurality of releaseably connectable conducting segments.
16. The dipole according to claim 15, wherein the segments include two segments for one of an Advanced Mobile Phone System frequency band and a Global System for Mobile Communication frequency band, one segment for one of a Digital Cellular System frequency band and a Personal Communication Services frequency band, and zero segments for an Industrial, Scientific and Medical frequency band.
17. A short assembly for a dipole antenna including a feed line connected to a first antenna element and a balun connected to a second antenna element, the short assembly comprising:
a first conductive portion; and
a second conductive portion detachably coupleable to the first conductive portion,
wherein, when the first and second conductive portions are coupled, the first and second conductive portions form two vias for receiving the balun and the feed line.
18. The short assembly according to claim 17, wherein the first and second conductive portions include threaded bores for being coupled together with a screw.
19. The short assembly according to claim 17, wherein, when coupled, the first and second conductive portions are slidable about a fitting, the coupled first and second conductive portions sliding relative to the balun and the feed line.
20. The short assembly according to claim 17, wherein the first and second conductive portions are formed from one of aluminum, brass and copper.
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 method of fabricating a bulk wave acoustic resonator comprising at least locally a partially suspended thin layer of piezoelectric material, and comprising the following steps:
formation of at least one first so-called lower electrode on the surface of a thin layer of piezoelectric material;
deposition of a so-called sacrificial layer on the surface of the thin layer of piezoelectric material and of the first electrode, defining a first set;
assembling of the first set with a second substrate;
formation of at least one second electrode termed the upper electrode on the opposite face of the said thin layer of piezoelectric material from the face comprising the first electrode;
elimination of the sacrificial layer so as to unveil the thin layer of piezoelectric material and the first electrode and define the bulk wave resonator.
2. The method of fabricating a resonator according to claim 1, further comprising manufacture of a sacrificial layer feature shrouding the said first electrode so as to construct the first set.
3. The method of fabricating a resonator according to claim 1, further comprising operation of local etching of the thin layer of piezoelectric material so as to allow the elimination of the sacrificial layer.
4. The method of fabricating a resonator according to claim 1, further comprising deposition of a planarizing layer on the sacrificial layer shrouding the said first electrode, prior to the assembling of the first set with the second substrate.
5. The method of fabricating a resonator according to claim 1, in which the second substrate comprises at the surface a layer that may be of the same nature as that of the planarizing layer on the surface of the sacrificial layer.
6. The method of fabricating a resonator according to claim 1, further comprising deposition of a protection layer prior to the deposition of the planarizing layer.
7. The method of fabricating a resonator according to claim 1, further comprising a step of planarizing the planarizing layer, prior to the assembling operation.
8. The method of fabricating a resonator according to claim 1, further comprising fabrication of the thin layer of piezoelectric material by the following steps:
definition of a thin layer of piezoelectric material within a first piezoelectric material substrate comprising the said first electrode and the sacrificial layer and defining a precursor set;
assembling of the precursor set, first electrode side, on the second substrate;
separation of the first piezoelectric material substrate from the said thin layer of piezoelectric material.
9. The method of fabricating a resonator according to claim 8, in which the definition of the thin layer of first piezoelectric material comprises the implantation of ions in the said first substrate so as to create in the piezoelectric material a buried weak zone defining the thin layer of piezoelectric material.
10. The method of fabricating a resonator according to claim 8, in which the separation is carried out by heat treatment.
11. The method of fabricating a resonator according to claim 1, further comprising:
assembling a first substrate of wholly or partly piezoelectric material, the piezoelectric material being covered with the first electrode and with the sacrificial layer together with the surface of a second substrate;
thinning the first substrate by lapping andor polishing so as to define a thin layer of piezoelectric material.
12. The method of fabricating a resonator according to claim 1, in which the assembling is performed by molecular bonding.
13. The method of fabricating a resonator according to claim 1, in which the piezoelectric material is of lithium niobate, lithium tantalate or quartz type.
14. The method of fabricating a resonator according to claim 13, in which the etching of the piezoelectric material layer is performed by photolithography and etching of the layer.
15. The method of fabricating a resonator according to claim 1, in which the sacrificial layer comprises a material of polymer or silicon oxide or metal type, possibly titanium, tungsten or molybdenum.
16. The method of fabricating a resonator according to claim 15, in which the elimination of the sacrificial layer is performed by attacking it with acid solution which may be of hydrofluoric acid or phosphoric acid, or Xenon fluoride type.
17. The method of fabricating a resonator according to claim 1, in which the planarizing layer is of silicon nitride, silicon oxide type or a metal of tungsten or aluminium type.
18. The method of fabricating a resonator according to claim 1, in which the intermediate layer is of titanium nitride or aluminium nitride type.
19. The method of fabricating a resonator according to claim 1, in which the second substrate is made of material of lithium niobate, lithium tantalate or quartz type.
20. The method of fabricating a resonator according to claim 1, in which the first andor the second electrode are made of a metal such as platinum, aluminium or molybdenum, or copper or tungsten or chromium or a copper and aluminium alloy or a silicon and aluminium alloy or Ruthenium.
21. A collective method for fabricating bulk wave acoustic resonators, each resonator comprising at least locally a partially suspended thin layer of piezoelectric material, comprising the following steps:
formation of a set of first so-called lower electrodes on the surface of a thin layer of piezoelectric material;
deposition of a sacrificial layer on the surface of the thin layer of piezoelectric material and of the first electrodes defining a first set;
assembling of the first set with a second substrate;
formation of a set of second electrodes termed upper electrodes on the opposite face of the thin layer of piezoelectric material from the face comprising the first electrodes;
elimination of the sacrificial layer so as to unveil the thin layer of piezoelectric material and the first electrodes and define the bulk wave resonators.
22. The collective method for fabricating bulk wave acoustic resonators (FBAR) according to claim 21, in which the lower and upper electrodes are defined so as to be able to carry out a grating type filtering function.
23. The collective method for fabricating bulk wave acoustic resonators (FBAR), according to claim 21, in which the lower and upper electrodes are defined so as to be able to carry out a ladder type filtering function.