System and method for modifying electrical characteristics

System and methods for modifying an electrical parameter of an electrical component are described. The system includes an electrical component disposed on a circuit board and a dielectric material. The electrical component has an electrical parameter that is sensitive to a dielectric constant of a substance proximate to the electrical component. The dielectric material is attached to the circuit board proximate to the electrical component and modifies the electrical parameter of the electrical component.

FIELD OF THE INVENTION

The present invention generally relates to systems and methods that modify electrical characteristics.

BACKGROUND OF THE INVENTION

Handheld wireless communications devices often employ, for example, quarter-wave transformers for cellular, personal communications services (PCS) or global positioning system (GPS) frequency bands. Such quarter-wave transformers, when not adapted, are typically much longer than can be easily accommodated by most handheld wireless communications devices.

In order to reduce the length of such quarter-wave transformers, a block20of dielectric material is used as shown inFIG. 3.FIG. 3shows a trace10that has been printed on a circuit board50. The trace10is not continuous as a space was provided onto which the dielectric block20could be mounted. The dielectric block20already has a trace40printed on its surface across three faces of the block20. The dielectric block20must be carefully aligned when it is mounted to avoid any discontinuities at point30between trace10of the board50and trace40of the block20. If successful, the dielectric block20modifies the electrical properties of the trace10,40such that a shorter trace can be used for a quarter-wave transformer, for example.

As is evident fromFIG. 3, there is very little room for error concerning the proper alignment of the traces10,40. Not only must the traces10,40be connected, but they must be well aligned since misaligned (albeit connected) traces10,40provide variances from the expected electrical characteristics of the trace10,40which can have deleterious effects on the handheld wireless communications device, especially during mass production.

In addition, since the block can only be mounted in one way, that is, with the traces10,40aligned and connected, there is no easy way in which to modify the electrical characteristics of the trace10,40in situ. Thus, a degree of flexibility is lost especially in light of the variability of the electrical characteristics of the traces10,40.

Accordingly, there exists a need for a method and a system of modifying the electrical characteristics of a trace that provide robust, well-aligned trace connections and also provides flexibility to change electrical properties in situ.

SUMMARY OF THE INVENTION

The present invention alleviates to a great extent the disadvantages of conventional apparatus and methods for providing a multiband antenna.

In a preferred embodiment, the present invention provides an electrical component disposed on a circuit board and a dielectric material. The electrical component has an electrical parameter that is sensitive to a dielectric constant of a substance proximate to the electrical component. The dielectric material is attached to the circuit board proximate to the electrical component and modifies the electrical parameter of the electrical component.

The present invention has an advantage in that the dielectric material is not required to complete the electrical component. Accordingly, problems such as alignment and continuity of the electrical component are reduced, if not eliminated.

The present invention also has an advantage in that the electrical properties of the electrical component can be modified, in situ, by placing the dielectric material in a different position or a different orientation relative to the electrical component.

These and other features and advantages of the present invention will be appreciated from review of the following detailed description of the present invention, along with the accompanying figures in which like reference numerals refer to like parts throughout.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1A and 1Billustrate an exemplary embodiment of a dielectric material70disposed on top of a trace60according to the present invention. The trace60may be printed or deposited on the circuit board50. Subsequently, the dielectric material is mounted or deposited on top of trace60.

Such a system may find application in wireless communications devices, for example, for use in a quarter-wave transformer. However, the present invention is not so limited and contemplates uses in any application in which the electrical properties may be modified or optimized. For example, the trace may be part of an antenna, an inductor, a capacitor, a resonating structure, transmission lines, wave-guides, etc. In addition, although illustrated as using a trace, the present invention contemplates using other electrical components known to one of ordinary skill in the art.

Since there is only the one trace60, there are no trace-to-trace continuity and alignment problems which might affect the electrical characteristics of the trace. In addition, since the disposition of the dielectric material70with respect to the trace60affects the electrical properties of the trace60, the dielectric material70can be mounted in different orientations and positions with respect to the trace60to optimize the expected electrical properties of the trace60.

For example,FIG. 2Ashows the dielectric material70that has been displaced, for example, along a direction that is perpendicular to the axis of the trace60. The trace60illustrated inFIG. 2Ahas different electrical properties than the trace60illustrated inFIG. 1B. Furthermore, althoughFIG. 2Aillustrates a particular displacement and orientation of the dielectric material70with respect to the trace60, it is understood that there are a wide variety of displacements and orientations of the dielectric material70from which to choose to provide additional degrees of freedom in optimizing or achieving particular electrical properties of the trace60.

FIG. 2Billustrates that adhesive dots80mounted on the circuit board50may be used to hold the dielectric material70to the circuit board50. Accordingly, the dielectric material70can easily be attached and detached from circuit board50. Thus, in attempting to achieve an optimized or particular electrical property of the trace60, the dielectric material70can be displaced or reoriented and easily mounted or dismounted from the circuit board50. With each mounting of the dielectric material70, the trace60could be tested to see if the particular electrical property had been achieved or optimized. Thus, for example, the trace60can be optimized for cellular band frequencies when the dielectric material70is in a first orientation and position, while the trace60can be optimized for PCS band frequencies when the dielectric material70is in a second orientation and position.

Although illustrated as adhesive dots80mounted on the circuit board50, other types and shapes of adherents may be used to attach and to detach the dielectric material70. For example, physical hooks or receptors could be mounted on the circuit board50in order to hold the dielectric material70on the circuit board50. In addition, the adhesive dots80may be disposed on the dielectric material70instead or in addition to the adhesive dots80on the circuit board50.FIG. 2Balso illustrates an example of adhesive pads90on the dielectric material that can be used to attach the dielectric material to the circuit board50.

In addition, although the dielectric material70has been illustrated as a block, the dielectric material70can take on any number of shapes and forms. Moreover, although the trace60has been illustrated as a line trace, other shapes and forms of the trace60known in the art are also contemplated. In addition, the particular choices available for materials for use in the dielectric material70and the trace60are well known in the art.

Although the dielectric material70has been illustrated as being on top of the trace60, the dielectric material70could equally be mounted under the trace60. For example, the trace60could be disposed on a first side of the circuit board50and the dielectric material70could be disposed on the second (opposite) side of the circuit board50.

Finally, although the dielectric material70has been illustrated in contact with the trace60, the dielectric material70may be in contactless proximity of the trace60. Such contactless proximity can still affect the electrical properties of the trace60.

Thus, it is seen that systems and methods for modifying electrical properties have been described. One skilled in the art will appreciate that the present invention can be practiced by other than the preferred embodiments which are presented in this description for purposes of illustration and not of limitation, and the present invention is limited only by the claims that follow. It is noted that equivalents for the particular embodiments discussed in this description may practice the present invention as well.