JP5345653B2 - PCB antenna - Google Patents

Abstract

A substrate antenna (400) that includes one or more conductive traces (402) supported on a dielectric substrate (404) having a predetermined thickness. Appropriate dimensions are selected for the lengths and widths of traces, based on the wavelength of interest, connecting elements, and space allocated. The supporting substrate (404) is mounted offset from and generally perpendicular to the ground plane (502) associated with the device with which the antenna is being used. The trace is electrically connected to a conductive pad (408) on one end. A signal feed (410) for the antenna is coupled to the conductive pad (408). The substrate antenna employs a very thin and compact structure which provides appropriate bandwidth. Antenna compactness and a greater variety of useful shapes allow the substrate antenna to be used very efficentiyl as an internal antenna for wireless devices.

Description

  The present invention relates generally to antennas for wireless devices, and more particularly to an antenna attached to a substrate. The invention further relates to an internal antenna for a wireless device having particularly improved dimensions, connections, frequency bands and radiation characteristics.

  An antenna is an important component of wireless communication devices and systems. Antennas are available in a variety of shapes and sizes, but each operates on the same electromagnetic principle. An antenna is a structure that couples a transition field between a guided wave and a free space wave or vice versa. As a general principle, guided waves that move along open transmission lines are emitted as free space waves known as electromagnetic waves.

  In recent years, with the increase in personal wireless communication devices such as mobile, mobile cellular and personal communication service (PSC) phones, the demand for convenient small antennas for such communication devices has increased. Recent developments in integrated circuit and battery technology have made it possible to significantly reduce the size and weight of such communication devices over the past few years. One field where size reduction is required is antennas for communication devices. This is due to the fact that the size of the antenna plays an important role in reducing the size of the device. Furthermore, the size and shape of the antenna affects the aesthetics and manufacturing costs of the device.

  One important factor that must be considered when designing an antenna for a wireless communication device is the radiation pattern of the antenna. In general application, a communication device must be able to communicate with other such devices or a satellite that can be placed in any direction from a base station, hub, or device. Therefore, it is essential that the antenna for such a wireless communication device has a substantially omnidirectional radiation pattern or a pattern extending upward from a local horizon.

  An important factor that must be taken into account when designing an antenna for a wireless communication device is the frequency bandwidth of the antenna. For example, wireless devices such as telephones used with PCS communication systems operate at a frequency band of 1.85-1.99 GHz, so 7.29 percent of the usable frequency bandwidth is required. The telephone used for a typical cellular communication system operates over the 824-894 MHz frequency band, which requires 8.14 percent bandwidth. Therefore, the antennas used in these types of wireless devices need to be designed to meet the proper bandwidth requirements, otherwise the communication signal will be significantly attenuated.

  A type of antenna commonly used in wireless communication equipment is the whip antenna, which can be retracted into the device when not in use. However, the whip antenna has several drawbacks. Often, whip antennas can hit objects, people, or surfaces and break when stretched for use or retracted. Even if the whip antenna is designed to be retractable in order to minimize such damage, it will extend the overall dimensions of the device, affecting the features of the latest technology and the installation of some circuits in the device. . There is also a need for a housing that is larger than desired to accommodate the minimum amount of equipment when retracted.

  Whip antennas are often used with short helical antennas, which are activated when the whip antenna is retracted into the phone. The helical antenna has the same radiation length in a more compact space, and maintains appropriate radiation coupling characteristics. Helical antennas are even shorter, but still protrude significantly from the surface of the wireless device, detracting from aesthetics and coming into contact with other objects. In order to fit such an antenna in a wireless device, a large volume is required, which is not preferable.

  Another type of antenna that may be suitable for wireless communication equipment is a conformal antenna antenna. In general, a conformal antenna is an antenna that generally traces the shape of a surface to which the antenna is attached and that hardly shows its appearance. There are various different types of conforate antennas such as patches, microstrips, and stripline antennas. Microstrip antennas are particularly recently used in personal communication equipment.

  For example, one type of antenna that may be suitable for use in a wireless communication device is an “inverted F” antenna, but the antenna has several drawbacks. The antenna is significantly larger in size than desired, has a lower frequency bandwidth, and lacks a preferred omnidirectional radiation pattern.

  As the term suggests, a microstrip antenna consists of a patch or microstrip element, which generally refers to a radiator patch. The length of the microstrip element is set in proportion to the wavelength λ0 associated with the resonant frequency f0 selected to match the relevant frequency, for example 800 MHz or 1900 MHz. Commonly used microstrip elements have a half wavelength (λ0 / 2) and a quarter wavelength (λ0 / 4). Although some limited types of microstrip antennas have recently been used in wireless communication equipment, further improvements are sought in several areas. One area that requires further improvement is overall downsizing. The other that requires significant improvement is the frequency bandwidth. Current patch or microstrip antenna designs have the preferred 7.29 to 8.14 percent frequency bandwidth characteristics required to use most practical size communication systems. I don't think so.

  Conventional patches and strip antennas also have problems that appear when placed near a large ground plane in most radios. The ground plane may change the resonant frequency and may not repeat the manufactured design. Furthermore, if it is “placed on the hand”, ie, the position of the user's hand is close to the antenna, it dramatically changes the resonant frequency and performance of the antenna.

  Radiation patterns are very important in relation to government radiation standards for wireless device users as well as to establish communication links, as explained above. The radiation pattern must be controlled or adjusted so that a minimum amount of radiation can be absorbed by the user of the device. There are government standards set for the amount of radiation allowed in the vicinity of wireless device users. One effect of these rules is that the internal antenna cannot be placed in many locations in the radio because the user is exposed to theoretical radiation. However, as noted above, when using current antennas elsewhere, ground planes and other structures often interfere with the effective use of the antenna.

  Therefore, in order to achieve a radio equipment internal antenna structure with a radiation pattern that more meets the latest radiation requirements for the end user, a new antenna structure and technology for manufacturing the antenna is required. At the same time, it is more conductive than the built-in, providing more resilient component positioning, significantly improved aesthetics, and even better antenna damage prevention measures in wireless devices. However, it is necessary for the antenna to meet the requirements for the frequency bandwidth and coupling efficiency of modern communication systems.

  In view of the above and other problems discovered in the technology relating to the internal antenna of a wireless device, a first object of the present invention is to provide an antenna that is downsized and can be elastically incorporated by the wireless device. It is.

  A second object of the present invention is to reduce the interaction between the user of the wireless device and the antenna, which will degrade performance.

  One advantage of the present invention is that it provides a support substrate that is physically deformable so that it can be incorporated into a wireless device.

  Another advantage is that it reduces manual labor and time for connecting and installing antennas in wireless devices, and reduces the number of cables and connectors required for that purpose.

  This and other objectives, goals and advantages are to realize a substrate antenna for use in wireless equipment, consisting of one or more conductive wires supported on a dielectric substrate having a predetermined thickness. is there. Appropriate dimensions are selected depending on the associated wavelength for the wireless device and the length and width of the trace based on the allocated space. The support substrate is offset from the ground plane associated with the circuitry and components in the equipment for using the antenna and is mounted perpendicular to the ground plane. That is, the substrate is attached adjacent to the end of the ground plane and has a surface that is offset by less than 90 degrees from the ground plane. The position of the substrate is not directly above or below the ground plane.

  The trace is electrically connected to a conductive pad at one end of the trace, and the one end is joined to a signal feeder for the antenna. Since a conductive pad is used, the signal feeding device consists of a conductive spring pressure, a spring or a clip-type device in which the electrical power is applied through the pressure on the conductive pad. Contact is formed. With this structure, when the board is installed in a wireless device, it can make automatic contact with the antenna without the installation of something like a cable or a connector by hand.

  The substrate antenna uses a very thin and compact structure, which provides an appropriate frequency bandwidth. The substrate antenna can be used very efficiently as an internal antenna of a wireless device with the compactness of the antenna and various easy-to-use forms. Despite the numerous possible interference characteristics or structures in the housing, the antenna can be placed in an advantageous location in the device housing to take advantage of space.

The perspective view of the portable radio telephone which has a whip form and a helical antenna. The side view of the portable radio telephone which has a whip form and a helical antenna. The perspective view and side view of the portable radio telephone which have another whip type and a helical antenna. FIG. 3 is a side view of the telephone of FIG. 2 with an exemplary internal circuit. FIG. 3 is a rear cross-sectional view of the phone of FIG. 2 with an example internal circuit. FIG. 4 is a side cross-sectional view of the phone of FIG. 3 with an exemplary internal circuit. 1 shows a substrate antenna according to one of the embodiments of the present invention. FIG. 3 is a side cross-sectional view of the phone of FIG. 2 using the present invention. FIG. 3 is a rear view of the telephone of FIG. 2 using the present invention. FIG. 3 is a side view of the phone of FIG. 2 using the present invention. FIG. 9 is a side cross-sectional view of the telephone of FIG. 8 of an alternative embodiment of the present invention. Fig. 3 shows multiple alternative embodiments of the present invention.

  The present invention has been described with reference to the attached figures, wherein like reference numerals generally indicate the same, functionally similar, or structurally similar elements. In the drawing, the first described element is indicated by the leftmost digit of the reference number.

  Conventional microstrip antennas, such as inverted-F antennas, have certain characteristics that can potentially disable personal communications equipment, while cellular and PCS phones such as Further improvements are still needed in this area in order to make this type of antenna convenient in wireless communication equipment. A further area for improvement is frequency bandwidth. In general, cellular telephones require greater frequency bandwidth than can be obtained with practically sized microstrip antennas in order to operate satisfactorily.

  Another area that needs further improvement is the size of microstrip antennas. For example, by downsizing a microstrip antenna, the wireless communication device can be made more compact and aesthetically pleasing. In fact, this can affect whether the antenna can be used for wireless communication devices. Conventional microstrip antenna downsizing may be done by reducing the required length by reducing the thickness of the dielectric substrate used or by increasing the value of the dielectric constant. . However, this has the undesirable effect of reducing the frequency bandwidth of the antenna and, as a result, not well suited for wireless communication equipment.

  Moreover, the magnetic field pattern of conventional microstrip antennas such as patch radiators is generally directional. Most patch radiators radiate only in the upper hemisphere with respect to the local level of the antenna. This pattern can move with the movement of the device or rotate to create undesirable holes in the transmitted and received radio wave reach. Therefore, the microstrip antenna has not been preferable for use in many wireless communication devices.

  The present invention provides a solution to these and other problems. The present invention focuses on substrate antennas that provide better frequency bandwidth and downsizing than other antenna designs while retaining other characteristics that are desirable for use in wireless communication devices. The substrate antenna of the present invention is constructed near the auxiliary surface of a wireless or personal communication device such as a mobile phone, or adjacent to other elements such as an I / O circuit or a keyboard in the wireless device. Or it can be mounted on the back side. The substrate antenna can also be embedded when the housing is plastic molded or constructed directly on the surface of the wireless device.

  Unlike a whip or external helical antenna, the substrate antenna of the present invention is not affected by damage due to hitting an object or surface. This antenna does not take up the internal space required for modern functions and circuitry, and does not require large housing dimensions when retracted. Since the substrate antenna of the present invention can be manufactured with automation and a minimum of manual work, the cost can be reduced and the reliability can be improved. Furthermore, since the substrate antenna radiates a pattern in almost all directions, it is suitable for many wireless communication devices.

  In a broad sense, the present invention can be used with any type of wireless equipment such as personal communications equipment, wireless telephones, wireless modems, fax machines, portable computers, pagers, message broadcast receivers, and the like. One such environment is a cellular radiotelephone used for cellular PCS or other commercial communication services. Various wireless telephones having various applicable housing configurations are known in the art.

  FIGS. 1-3 show a typical wireless telephone used in a wireless communication system such as the cellular and PCS systems described above. The phone shown in FIGS. 1 and 2 is a “clamshell” or foldable phone, whereas it is shown in FIGS. 3 (a) and 3 (b). The phone that is used is a typical rectangular or “bar” phone. These telephones are typical wireless telephones used in wireless communication systems such as cellular and PCS systems, as described above. These telephones are used for illustration purposes because there are many types of wireless devices and telephones, and these and other related types or styles of physical that the present invention may use. The shape becomes clear from the following explanation.

  1 and 2 illustrate a telephone 100 having a main housing or body 102 that supports a whip antenna 104 and a helical antenna 106. The antenna 104 is generally not required for correct operation, but is attached to a common central axis that is shared with the antenna 106 when extended. These antennas are manufactured with a length that is tailored to the associated frequency or the frequency used for a particular wireless device. The particular design is known and understood in the relevant art.

  The front surface 102 of the housing is shown supporting a speaker 110, a display panel or screen 112, a keyboard 114, a microphone or microphone opening 116, and a connector 118. In FIG. 2, the antenna 104 is in the extended position when the wireless device is used, but the antenna 104 in FIG. 1 is shown in the retracted position in the housing 102.

  3 (a) and 3 (b), phone 200 having a main housing or body 202 that supports whip antenna 204 and helical antenna 206 is shown in the same manner as phone 100. FIG. The front surface 200 of the housing is shown supporting a speaker 210, a display panel or screen 212, a keyboard 214, a microphone or microphone opening 216, and a connector 118. In FIG. 3 (a), the antenna 204 is in the extended position, whereas the antenna 204 in FIG. 3b is shown in the retracted position in the housing 202.

  As explained above, whip antennas 104 and 204 have several disadvantages, one of which is susceptible to breakage when caught for other items or surfaces when extended for use. That is. The antennas 104 and 204 also take up internal space in such a way that the placement of components for current characteristics and circuits, including a power source such as a battery, is constrained and reduces elasticity. In addition, the antennas 104 and 204 require a minimum storage dimension that is unacceptably large when retracted. Alternatively, to reduce size when retracted, the antennas 104 and 204 can be configured with a telescoping part, but generally looks less aesthetic and weaker It may be unstable, or it may be seen by users as unwieldy. The antennas 106 and 206 are also susceptible to being damaged by other objects or surfaces during use and cannot be retracted into the telephone housings 102 and 202, respectively.

  Although the use of the present invention has been described in the sense of an exemplary wireless telephone for convenience, it is not intended to limit the invention to the illustrated environment. After reading the following description, it will become apparent to one skilled in the art how the invention can be implemented in alternative environments. In fact, the present invention is apparently applicable to other wireless communication devices such as, but not limited to, pagers, portable fax machines, and portable computers with wireless communication capabilities.

  Each of these telephones typically has various components that are supported by one or more circuit boards to perform various necessary functions. 4-6 are used to illustrate the general internal structure of a typical radiotelephone. FIG. 4 shows a cross-sectional view of the telephone of FIG. 2 viewed from the side to see how to support the circuitry or components in the housing 102. FIG. 5 shows a cut-away cross section of the same phone, viewed from the back and back of the keyboard, to see the relationship between the circuitry and components generally within the housing 102. FIG. 6 shows a cross-section of the phone shown in FIG.

  4 and 5, a circuit board 302 supports an integrated circuit or chip 304, discrete components 306 such as resistors and capacitors, and various components such as various connectors 308. Is shown inside. The panel display and keyboard are typically attached to the back side of the circuit board 302, and wires and connectors (not shown) connect speakers, microphones, or similar elements to the circuit on the circuit board 302. ing. The antennas 104 and 106 are located on one side and connected to the circuit board 302 using special wire connectors and clips for this purpose.

  In general, a predetermined number of posts or supports 310 are used in the housing 102 for mounting circuit boards and other components within the housing. These columns can be formed as part of the housing, such as when molded with injection molded plastic, or attached in place with an adhesive or other known mechanism. In addition, there are one or more fixing posts 312 that are typically used to receive screws, bolts or similar fasteners 313 to secure portions of the housing 102 together. That is, the housing 102 is manufactured using a large number of parts or a cover that covers the main body portion and the electronic parts. The fixing post 312 is used here to receive an element 313 for fixing the housing parts to each other. The present invention provides a very efficient internal antenna design that easily accepts or allows for the various struts 310 or 312.

  As can be seen in the enlarged view of FIG. 5, the circuit board 302 is typically a multi-layered structure in which multiple conductors and dielectric substrates are alternately bonded to form a fairly complex circuit interconnect structure. Manufactured on a circuit board. This substrate is a known technique. As part of the overall structure, the substrate 302 has at least one, and possibly more, ground layer or ground plane embedded in the substrate on the bottom surface or in an intermediate position. ing.

  Applicants have discovered that this is the interaction of any antenna 104, 106, 204 or 206 with a ground plane forming a radiation pattern for the wireless device. The antenna effectively excites the ground plane. That is, there is a current directed between the conductive material in the whip or helical antenna and the ground plane that generates electromagnetic waves that are radiated into the air to form communication signals. This is a combination for receiving an incoming signal received by the wireless device. For this and other reasons, the Applicant has discovered that a large and useless antenna can be replaced with a smaller and more compact antenna element provided that it is properly positioned with respect to the ground plane of the wireless device. did.

  It has been found that others other than the applicant have attempted antenna radiating elements that require a certain amount of shielding on the ground plane in creating the internal antenna position. Unfortunately, this has resulted in failure to create a low loss match for the antenna with sufficient operating frequency bandwidth for use with normal cellular and PCS. That is, as a result, the antenna is very inefficient and has a low gain, often reducing the gain by about 6 dB.

  A substrate 400 constructed and operated in accordance with one embodiment of the present invention is shown in FIGS. 7 (a)-(c). 7 (a) and 7 (b), the substrate 400 comprises a conductive trace 402, what is referred to as a strip or extended conductor, a dielectric support substrate 404, and a signal feed region 406. . The conductive traces 402 can be manufactured or viewed as two or more traces that are electrically connected in series with each other to form a preferred antenna radiator structure. Trace 402 is electrically connected to a conductive pad 408 in one end of substrate 404 or adjacent signal feed region 406.

  Substrate 404 is made of a dielectric material or substrate such as a circuit board or flexible material known to be suitable for use. For example, a printed wiring board (PCB) based on small glass fibers can be used. Various materials are available for manufacturing the substrate. Generally commercially available glass fiber, phenyl, plastic, or other printed wiring boards or substrate materials can be used. Although it is not necessary to use a thin substrate, it provides the advantage that it is deformable and can be mounted in place. A sheet of Teflon reinforced with very thin glass fibers can be used for a very thin substrate, which is preferred for large bending and flexing, but such a thin material is a characteristic of the antenna However, it may not provide sufficient support strength to prevent changes in the phone movement. Those skilled in the art of electronics and antenna design are familiar with the various products for which suitable antenna substrates are available based on favorable dielectric properties or frequency bandwidth characteristics of the antenna.

  The substrate is spaced from the support and other conductive surfaces, here the antenna radiator elements, here traces, or provide minimal spacing from hands or other radiation absorbing or interacting materials (such as tissue) As a means to

  The trace is made, for example, from a conductive material such as copper, brass, aluminum, silver or gold or other conductive material known as convenient for manufacturing antenna elements. The material includes a conductive material embedded in plastic or conductive epoxy that serves as a substrate.

  The trace (s) include, but are not limited to, photoetching of standard conductive material on a dielectric or insulating substrate, plating or deposition of other conductors on the substrate, or adhesive It can be deposited using one of a number of known techniques, such as the placement of a conductive material such as a thin metal plate on a support substrate. In addition, known coating or vapor deposition techniques can be used to deposit metal or conductive materials onto plastic support elements or substrates that can change shape.

  The length of the trace 402 uniquely determines the resonance frequency of the substrate antenna 400. The size of the trace 402, or series of connected traces, is adapted to the specific operating frequency. The traces used to construct the antenna are deposited to provide a conductive element that is approximately ¼ effective wavelength (λ) for the relevant frequency. One skilled in the art will appreciate the advantage of making the length slightly smaller or larger than λ / 4 for the purpose of matching the impedance to the corresponding transmit or receive circuit. In addition, connecting elements such as exposed cables, wires or clips, described below, will affect the overall length of the antenna and, as is known, are taken into account when choosing the trace dimensions.

  When the substrate antenna 400 is used for a wireless device that can communicate at two or more frequencies, the length of the trace 402 is based on a frequency relationship. That is, it is possible to accept multiple frequencies on condition that the multiple frequencies are in a fractional relationship of wavelengths. For example, the length of λ / 4 of one frequency corresponds to 3λ / 4 or 2λ / 2 with respect to the second frequency. Such a relationship for using a single radiator for multiple frequencies is well understood in the known art.

  The trace (s) 402 is an approximately small fraction of the normal wavelength to minimize or prevent crossing currents or modes and maintain a minimum antenna size (thickness). The selected number is based on the frequency bandwidth at which the antenna must operate as is known in conventional antenna technology. The width of the trace (s) 402 is also below the wavelength level in the dielectric substrate material because higher order modes are not excited.

  The total length of the trace 402 is approximately λ / 4, but may be folded, bent, or otherwise reoriented to stretch the trace back along the direction it originally came. It must be noted that this makes the antenna structure much shorter than λ / 4. The size of the thin conductor combined with a relatively thin support substrate and a length of λ / 4 or less allows a significant downsizing of the entire antenna compared to a conventional strip or patch antenna, and the structure Therefore, it can be preferable for the use of personal communication devices. For example, the dimensions are compared to a conventional microstrip antenna ground plane, which is typically at least λ / 4 in size for proper operation.

  As shown in FIGS. 7A and 7C, the position of the conductive pad 408 is in the signal feeding region 406 and is electrically connected to the trace 402. In general, the pads 408 and traces 402 are not necessarily required, but are formed of the same material, and in some cases, as a single unit or a single structure using the same manufacturing techniques. Pad 408 need only be in electrical contact with trace 402 to transfer the signal without adversely affecting the impedance or performance of the antenna.

  In some structures, the traces face the circuit board and the signal source or receiver, and in other structures, they face away from the board. In the latter situation, the location of the conductive pads 408 is the backside of the substrate so that it can be received directly from the circuit board without the need for wires or other conductors extending around the substrate. It is in. In many applications, this is undesirable because it requires more complex connections and installation procedures. Thus, as shown in FIG. 7 (c), the second contact pad 410 is used on the back side of the substrate (as seen in FIG. 8) and for transferring signals through the substrate. Conductor bias can be used.

  The signal transfer power supply device is connected to the substrate antenna 400 using the pads 408 (and 410). By using conductive pads 408 (and 410), antennas can be installed for convenient electrical connection and signal transfer via conventional “spring type” or spring-loaded contacts or clips. It can be operated in the way provided. This structure simplifies the construction and manufacture of wireless equipment by eliminating manual installation with a custom connector or by manually inserting the antenna into the contact structure. This type of electrical connection also allows the antenna to be re-soldered or special connectors, etc., if necessary, for repair, or to upgrade radio equipment or change to other frequencies Means that it can be easily exchanged. As explained above, spring contact contributes to the overall length of the antenna or antenna radiator (trace) and must be taken into account when selecting the trace dimensions.

  The signal power feeding device connects a signal from the signal processing device or a circuit (not particularly shown) on the circuit board 302 to the board antenna 400. “Circuit” is used to refer to the functions provided by all known and generally known signal processing circuits including receivers, transmitters, amplifiers, filters, transceivers, etc. You must keep in mind.

  8 and 9, the antennas 104 and 106 are replaced with a substrate antenna 400. The circuit board 302 is shown in FIG. 8 as consisting of multiple layers of conductive and dielectric material such as copper and glass fiber being formed, referred to as multi-layer board or printed wiring board (PCB) technology. . This is illustrated as a dielectric layer 502 next to the metal conductor layer 508 or on top of the metal conductor layer 504 next to the dielectric material layer 506 supporting the metal conductor layer 508 or next to the metal conductor layer 504. . Conductor bias (not shown) is used to interconnect various conductors on various layers or levels with components on the outer surface. The etched pattern on every given layer determines the interconnect pattern for that layer. In that form, either layer 504 or 508 can be formed on a ground layer or surface pointing to substrate 302 as generally known techniques.

  The antenna 400 is mounted adjacent to the circuit board 302 but is offset from the ground plane (GP) and is disposed with the board 404 substantially perpendicular to the ground plane (GP). The arrangement provides a very thin profile for the antenna 400 so that the antenna can be placed in a very constrained space and adjacent to the surface of the housing 102. For example, the location of the antenna 400 can be between a fastener or mounting post and the side (upper surface) of the housing 102 that cannot be achieved using conventional microstrip antenna designs.

  As an option, the pillar can now be used to automatically position and support the antenna 400 without an additional support mechanism or fixture. In order to determine the predetermined position of the substrate, several support means are required, and this structure reduces the cost for antenna installation and allows for a simple attachment mechanism that can be automated. Can be provided. Due to the nature of the method of attaching the substrate in place, the substrate need only be placed on the housing. The circuit board can simply be placed over the housing using a push-in fitting of the display panel or connector 118 mated via a hole or passage in the housing.

  Among alternatives, can the substrate 404 be mounted in place in the wireless device using something like a small bracket, post, ridge, ridge, slot, channel, support extrusion, protrusion, or Alternatively, a similar one molded from the material used to manufacture the walls of the housing 102 can be used to place the substrate. That is, the support can be molded or molded to the wall of the device housing when manufactured, such as by injection molding. With the support element, the substrate 404 can be held in place or attached to the element using fasteners when inserted into or between them during phone assembly. . A ridge or tab formed in the wall of the housing (or post) can be snapped around the edge of the substrate to help hold it in place.

  Another means for attachment is the use of an adhesive or tape to hold the substrate to the side walls or other parts or elements to the wireless device.

  As seen in FIG. 9, the substrate 404 can be curved or bent to match the shape of the housing as much as possible, or to accommodate other elements, parts, or components within the wireless device. it can. The substrate can be manufactured in this shape or deformed during installation. By using a thin substrate, the substrate can be fixed or bent when attached, and the substrate can be pressed into place with pressure against an adjacent surface. The pressure can generally help to secure the substrate in place without screws or other types of fasteners.

  However, one of ordinary skill in the art should readily recognize that there is no need to deform or bend the substrate during manufacture or installation in order to properly operate the present invention. A straight flat substrate exhibits a good function as a basic shape. Other forms also have the advantage of being housed under various mounting conditions, but do not change the operation of the present invention.

  Once all the parts, etc. are in place, the cover or plate on the back of the housing is secured in place with screws, bolts or other methods. This is accomplished in such a way that the antenna or board is “captured” within the housing simply by attaching an adjacent circuit board and cover or housing that are fixed in place. No additional fasteners or securing elements are required for the antenna in this effort. A set of tabs, or similar protrusions, can be used to interface with the cover at certain points to reduce the number of screws required to hold the antenna in place.

  The conductive pad 408 is placed in a location adjacent to and electrically connected to the substrate 302 using a spring, spring contact or clip 510. The spring contact or clip 510 is mounted on the circuit board using known techniques such as soldering or conductive bonding. The clip 510 is electrically connected at one end to a suitable electrical conductor or conductive bias to transfer signals to or from the desired circuit or circuits in the wireless device, The circuit is connected to the antenna 400. The other end of the clip 510 is generally not fixed and floats, and extends from the circuit board 302 toward the place where the antenna 400 is to be placed. More specifically, the clip 510 is placed adjacent to the end of the trace 402 where the contact pad 408 is placed. As shown in each figure, clip 510 is bent into a circle away from the antenna and then arcs until the clip is directed back toward the antenna. Although the circular arc makes the work on the substrate more elastic and simple, other types of clips seen in FIG. 11 are also known to be useful and the present invention provides: It is not limited to this. The spring contact or clip 510 is generally manufactured from a metallic material such as copper or brass, but for this application, as known in the art, subject to signal attenuation or other favorable contact characteristics. All known deformable conductive materials can be used.

  Since the antenna 400 is not placed over a ground plane such as the layer 504, ie, in parallel and directly adjacent, the antenna has or maintains a sufficiently large radiation resistance. This means that there is no significant loss, i.e. the antenna can have a good matching impedance and provide adequate matching to the antenna 400. This efficiency is maintained as long as the antenna 400 is moved to various shifted positions on one side of the circuit board 302, i.e. the antenna is moved laterally, as long as it does not approach the board 302. . This antenna design serves as a very efficient means to excite the ground plane (GP) without compromising performance.

  Although a substrate perpendicular to the ground plane is not required, the main feature of the present invention is the small size and the least space available. Obviously, if the substrate is placed on the same plane as the ground plane and in parallel, it takes up more space between the housing and the ground plane. This is not preferred, but the direction of the substrate does not interfere with the operation of the antenna. A conventional patch antenna must be used, which is why it requires a lot of space. The present invention differs in that the antenna can use a small lateral space in the wireless device.

  By placing the antenna near the ground plane (GP) and beyond the end of the ground plane (GP) with respect to the housing, the antenna provides a much more omnidirectional pattern than conventional whip antennas To do. This position of the antenna also means that the resulting radiation pattern is polarized approximately vertically, which is preferred for most wireless communication devices.

  The board should not be placed “above” or “below” the ground plane (GP) with respect to the electronic components in the wireless device. As explained above, the reason is that, in this position, impedance can adversely affect performance. It is important that the antenna must not be above the ground plane. This can be revealed in several ways. For example, there is a volume or space on the upper surface of the ground plane, which occupies the ground plane end (enclosed by the edge). This volume is an exclusion region or area for the substrate. Placing the trace in this volume means placing it on the ground plane. From another point of view, any lift or offset angle between the position of the ground plane and the substrate antenna cannot be more than 90 degrees from the plane of the ground plane. In fact, it must be much smaller than 90 degrees to ensure proper or sufficient separation from the ground plane.

  Another way to focus on the antenna, and thus the substrate, is to focus on the advantages that positioning creates with the design. This antenna can be mounted between the ground plane (GP) and the side wall (depending on the viewpoint or on the top or bottom wall) near the top of the wireless device. In the case of a foldable phone, the antenna can be mounted between two, m portions, near a hinge or pivot or pivot connection. This provides a location for the antenna that is further away from the user, such as the user's head, during use due to the nature of the way the phone is opened and the connection location. This is a clear advantage in terms of head absorption and the like. For “bar” phones or wireless devices, a substrate antenna can be mounted on the top or side as desired.

  The present invention is the first invention having a form in which the space or region can be used. In this sense, the present invention is a new method that utilizes the space, volume, or area of a wireless device that is adjacent to the circuit board and next to the housing and offset from the ground plane (GP). It is a new type of internal antenna that can be installed in a region immediately adjacent to the ground plane (GP).

  An advantage of the present invention is that it does not require a removal portion of the substrate to be attached or placed in place. Large patch antennas or elements require the large area or area necessary to provide a place to attach the removed circuit board or parts of the removed circuit. Another aspect of the antenna is that the antenna is mounted aligned to a generally planar plane. That is, the antenna radiating device is formed in a planar shape (even if the radiating device is bent), and the plane axis is aligned with the plane axis of the ground plane (GP). The loss of space that fails in part of it causes the space to be abused by the antenna.

  It should be construed that the trace 402 shown in FIGS. 7-9 is considered sensitive to changes in the effective resonance length. This part is the part that most easily represents the change in resonance of the antenna due to the presence of the hand or head of the user of the wireless device. There are three main energy losses that affect the operation of the antenna 400 in the wireless device. They are impedance mismatch losses due to the absorption of the user's hand, the absorption of the user's head, and the absorption load of the user's hand. The energy absorption or mismatch loss can degrade performance. For example, hand or head absorption can significantly attenuate signals used by wireless devices and degrade performance.

  The most susceptible parts of the antenna 400 are the open end of the antenna 402, the non-feed, and the adjacent bent part. The point of the antenna can be in the phone housing so that the user's hand is most difficult to touch or sufficiently spaced from the hand. In this antenna design, to minimize hand absorption, and more importantly, to reduce mismatch loss created by the presence of hands or other items adjacent to the antenna (such shifts are desired). Except for when), the installation location in the wireless device can be made elastic.

  Another aspect of small antenna size and installation site elasticity is the potential impact on energy levels that are close to the user of the device. The smaller size and elasticity of the antenna affects the location of the antenna within the housing, which can greatly affect the radiation level experienced at specific locations outside the equipment.

  In addition, to assist in downsizing the antenna or providing elasticity in a set position within the housing 102, the antenna is placed or deposited with a conductive material on the housing or in the surface of the wireless device. Can be formed. That is, the trace can be deposited or molded directly above the wall for applications where there is a clear passage along the side wall of the housing. This is shown in the cross-sectional view of FIG. In FIG. 11, the trace (s) are disposed on a housing that acts as a direct support substrate. Now you can take advantage of the minimum space.

  The portion of the housing wall that is used can be coated with metal or made of metal or other electrically conductive material, and an intermediate layer of insulating material can be used between the housing and the trace 402. Within this shape, a metal layer having a preferred trace configuration is formed on a thin layer of material having an adhesive material on the back that can be easily placed in a wireless device simply by pressing against the side of the housing. be able to. This method can even be automated using known “pick and place” machines. In this or other embodiments, the traces can be further used in a known technique, such as a coating for surface protection.

  However, it should be noted that the relative placement of the antenna or conductive material relative to the ground plane (GP) must be the same as described above in the sense that it must not be above the ground plane (CP). It is clear to the contractor.

  FIG. 12 shows several alternative embodiments for the trace in forming the antenna of the present invention. In FIG. 12 (a), the trace 402 extends along the length of the substrate 404 (not shown) and is connected to or formed to one end of the round contact 408. Are shown as a single thin conductive strip. In FIG. 12 (b), the trace 402 is connected to the contact pad 408 and is a single thin conductive strip having an enlarged or rounded portion formed on the non-contact end. This trace has the appearance of a “dog bone”. In FIG. 12 (c), trace 402 is a thin conductive strip that is connected to or molded into a longer, more angular contact pad 408. Here, the strip extends along the length of the substrate 404 and is folded or bent near the distant non-contact end so that it is returned and redirected in the direction of the contact pad. This allows the total length of the antenna to be shorter than the length of the trace used to form the λ / 4 length element. As stated above, it should be understood that various patterns or configurations can be used to modify or fold the direction of the trace along various directions. For example, square corners, circular bands, or other configurations can be used for this function. The trace also has a folded portion wider than the other portions. As shown in FIG. 7 (b), the increased width provides “top load” or improved frequency width for the antenna, which is useful for some applications. The extra width is not required by the present invention.

  In FIG. 12 (d), the trace 402 is again shown as a conductive strip connected to a contact pad 408 extending along the length of the substrate 404. In this embodiment, the traces have a more complex form along the edge of the substrate manufactured with a dent or a recess at the opposite end corresponding to a tab or protrusion along one end. . The trace is turned in two turns before reaching the farthest end of the substrate where the trace is folded towards the contact end. The last part of the trace after being folded is also slightly larger than the original length of the trace.

  Tabs and other angles and depressions along the length of the substrate serve to contact the features of the wireless device housing and the sides of the various support elements. That is, the edge of the substrate 404 can be variously shaped to mate with the housing. The edge shape is matched or arranged with a corresponding deformation in the housing wall to avoid various bumps, protrusions, irregularities or known protrusions from the surface of the housing wall, or wireless equipment You can even leave room for wires and conductors and cables that need to be placed inside. Various round, square or other shapes can be used for this purpose on the sides or edges of the substrate. At the edge, the antenna can be mounted in a space that has not previously been suitable for a microstrip antenna.

  Furthermore, the trace 402 or the substrate antenna 400 can also be changed in a three-dimensional sense. That is, while the trace is generally formed with a planar surface, the substrate supporting the trace or the surface of the substrate can be curved or bent into various mounting shapes. That is, since the substrate is generally thin but tough, it can be fabricated to be deformed into a curved or curved structure, variable surface, or end during attachment. This is shown in the top view of the substrate, FIG. 12 (e) showing the substrate 404 curved transverse to the length. It will be apparent to those skilled in the art that various curves or bends can be used within this feature. For example, the substrate surface can also be formed into some kind of “curved” pattern.

  A preferred embodiment of the invention constructed and tested is shown in the side and front views of FIGS. 12 (f) -12 (h). Here, the substrate 402 is about 52 mm long and the trace is made about 1 mm. The trace is unrolled close to the end 702 of the part to be folded and approaches 1.5 mm. Both contact pads 408 and 410 were made to be about 6.75 millisquare conductors with the appropriate conductor vias connecting the two through the substrate. A glass fiber substrate with a thickness of about 1 mm was used, and the thickness of the traces and pads was about 0.01 mm. Note the space 704 between the end of the folded trace and the end of the substrate. Optional end space or gap helps set the back of the trace to further reduce the effects of the hand approaching or touching the end of the antenna.

  For those skilled in the art, various forms such as, but not limited to, round, oval, parabola, bent, square C-shaped, L-shaped or V-shaped folding joints and ends, for traces and substrates It is clear that it can be used. To increase or decrease the width toward the outer end (non-powered portion), the width of the conductor can be varied along the length to taper, curve and change in stages. As those skilled in the art will appreciate, a plurality of these effects or shapes can be combined into a single antenna structure. For example, bent, graded strips are possible that are later curved along other dimensions.

  The result of removing whip antenna 104 and spiral antenna 106 is apparent in the side view of FIG. 10 showing the telephone of FIG. 2 using the present invention.

The previous description of the preferred embodiments enables those skilled in the art to utilize the invention. Various modifications to these embodiments will be apparent to those skilled in the art, such as the type of radio equipment of the type used therein, and are comprehensive as defined herein. This principle can be applied to other embodiments without using inventive talent. Accordingly, the present invention is not limited to the embodiments shown herein, but is applied to the widest scope consistent with the principles and novel features disclosed herein. Shall. The same description as the claims at the beginning of the filing of the present application will be appended as “Other Examples”.
[Other Example 1]
In a substrate antenna for use in a wireless communication device having a ground plane for a circuit incorporated therein,
A non-conductor support substrate having a predetermined thickness and length;
A conductive trace formed on the support substrate having a length selected to operate as an active radiation device of electromagnetic energy at at least a predetermined frequency;
The board | substrate antenna by which the said support substrate is arrange | positioned in the said radio | wireless communication apparatus in the vicinity of the said ground-surface end, and beyond.
[Other Example 2]
The substrate antenna according to other example 1, wherein the trace is formed by depositing a metal material on a dielectric material.
[Other Example 3]
The board | substrate antenna of other Example 1 further provided with the electrically conductive pad connected to the electric power feeding end of the said trace.
[Other Example 4]
The substrate antenna according to the third embodiment, in which the conductive pad is connected to a spring-type signal feeding.
[Other Example 5]
The length and width of the trace are the substrate antennas according to the other embodiments, which are sized so that the substrate antenna can transmit and receive a signal having a frequency width of 824 MHz to 894 MHz.
[Other Example 6]
The substrate antenna according to the other embodiment 1, wherein the length and width of the trace are such that the substrate antenna can transmit and receive a signal having a frequency width of 1.85 GHz to 1.99 GHz.
[Other Example 7]
The board | substrate antenna of other Example 1 with which the said board | substrate is arrange | positioned adjacent to the said grounding surface edge, and is offset at an angle of 90 degrees or less from the said grounding surface.
[Other Example 8]
The board | substrate antenna of other Example 1 with which the said board | substrate is arrange | positioned in parallel with the said ground-surface end.
[Other Example 9]
9. The substrate antenna according to another embodiment 8, wherein the substrate is disposed substantially perpendicular to a plane including the ground plane.
[Other Example 10]
The board | substrate antenna of other Example 1 in which the said board | substrate is not arrange | positioned directly on or under the said ground plane.
[Other Example 11]
The board | substrate antenna of other Example 1 with which the said board | substrate is arrange | positioned between the said ground-surface end and the wall of the housing for the said radio | wireless apparatus.

Claims (13)

In a substrate antenna that is arranged and used in a wireless communication device having a planar ground plane for a circuit incorporated therein,
A non-conductor support substrate having a predetermined thickness and length and having a configuration spaced from the ground plane;
Comprising an antenna radiating element in the form of a conductive trace formed on the support substrate;
The conductive trace has a feed end and an open end and is an effective length selected to operate as an active radiation device of electromagnetic energy at at least one predetermined frequency and is approximately four minutes of the electromagnetic energy. Has an effective length of one wavelength,
A conductive pad connected to the power feed end of the trace and performing signal transmission between the radiation device and another circuit;
The support substrate is disposed in and near the planar ground plane end in the wireless device, and the support substrate includes a housing side wall near the top portion of the wireless device and the wireless device. It is attached between the ground plane and is disposed substantially perpendicularly to the ground plane,
The conductive pad is electrically connected by a spring-type signal feeding and spring pressure attached to a substrate on which the circuit is arranged, wherein the substrate antenna is located at a predetermined position in the wireless device. A substrate antenna that is attached and detached against pressure. The substrate antenna according to claim 1, wherein the trace is formed by depositing a metal material on a dielectric material. The substrate antenna according to claim 1, wherein the effective length and width of the trace are such that the substrate antenna can transmit and receive a signal having a frequency width of 824 MHz to 894 MHz. 2. The substrate antenna according to claim 1, wherein the effective length and width of the trace are such that the substrate antenna can transmit and receive a signal having a frequency width of 1.85 GHz to 1.99 GHz. . The substrate antenna according to claim 1, wherein the support substrate has a plane axis that is disposed adjacent to the end of the ground plane and is offset from the ground plane by an angle of less than 90 degrees. The substrate antenna according to claim 1, wherein the support substrate has a plane axis arranged in parallel with the end of the ground plane. The substrate antenna according to claim 6, wherein the support substrate is further in a plane disposed substantially perpendicular to the plane of the ground plane. 2. The substrate antenna according to claim 1, wherein the support substrate is not disposed directly above or below a plane occupied by the ground plane. The substrate antenna according to claim 1, wherein the support substrate is disposed between the end of the ground plane and a wall of the housing for the wireless device. The substrate antenna according to claim 1, wherein the radiation device extends along a straight path between first and second ends of the support substrate. The substrate antenna according to claim 1, wherein the radiating device is further bent near one end of the support substrate and extends toward an opposite end. The substrate antenna according to claim 1, wherein the support substrate includes an integral part of the housing for the wireless device. 2. The substrate antenna according to claim 1, wherein the support substrate includes a support component fixed at a predetermined position on the housing for the wireless device.

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