BRPI0803648B1 - ANTENNA APPARATUS FOR A RADIO DEVICE AND METHOD FOR TRANSDUCING A SIGNAL ENERGY FROM A RADIO DEVICE - Google Patents

Abstract

dual-polarized multiple ribbon loop antenna and associated methodology for an audio device. a dual-polarized antenna and associated methodology are provided for a radio device, such as a mobile station. the antenna is formed by a plurality of loop tapes arranged on a substrate. the loop ribbons are configured on a pair of L-corner antennas, with the loops sharing a shared set of loop ribbons. a loop strip of the shared set provides a unique power connection positioned to allow symmetrical excitation of the antenna.

Description

The present invention generally relates to an antenna for a portable radio device, such as a Bluetooth or IEEE 802.11 capable device, which operates in the frequency band of IMS (Industry, Medical and Scientific Area). More particularly, the present invention relates to a dual-polarized antenna and an associated methodology of compact construction, capable of positioning on or within a radio housing of the portable radio device.

L-shaped corner antenna loops formed by loop tapes are disposed on a substrate. Loop tapes extend in a first bias direction or a second bias direction. The loop tapes are of dimensions and are connected together to be resonant in the frequency band of IMS, or other selected in orthogonal polarization directions.

Background of the Invention

Radio communication systems are used by many in modern society to communicate. A wide range of communication services, voice communication services and data communication services, are regularly carried out by means of radio communication systems. And, as technological advances allow, the types of communication services effectable through radio communication systems are likely to increase accordingly.

Cellular communication systems are an example of radio communication systems that have high levels of usage. Cellular communication systems are typically built to provide wide area coverage. And, its infrastructure has been installed by significant portions of the world's populated areas. A user communicates through a radio communication system through the use of a wireless device, a radio transceiver, sometimes referred to as a mobile station or user equipment (UE). Typically, an access to a cellular communication system is provided in line with the purchase of a subscription, on a renewed basis, eg, monthly, or on a time-use, pre-paid basis. Cellular communication systems, operable in line with different operating standards, define radio air interfaces in different frequency bands, for example, in the 800 MHz frequency band, in the 900 MHz frequency band and in the bands located between 1.7 GHz and 2.2 GHz.

Other types of radio communication systems are also widely used, for example, systems based on Bluetooth™ and IEEE 802.11, implemented, for example, as WLAN (Wireless Local Area Network) systems, also provide voice and data communications. , usually by coverage areas smaller than their cellular counterparts. WLANs are regularly operated as private networks, providing users who have access to these networks the ability to communicate over there through the use of wireless devices with Bluetooth or 802.11 capability. WLANs are sometimes configured to be connected to public networks such as the Internet and in turn to other communication networks such as PSTNs (Public Switched Telephone Networks) and PLMNs (Public Land Mobile Networks). Cooperative working entities are sometimes provided for the provision of a more direct connection between small area networks and a PLMN. Several of the systems mentioned above are implemented in the 2.4GHz frequency band.

Radio communication systems are generally bandwidth-constrained. That is, the bandwidth allocations for your operation are limited. And this limited bandwidth allocation imposes limits on the communication capacity of the communication system. Significant efforts have been made and attention has been directed towards ways in which to efficiently utilize the limited bandwidth allocated in constrained bandwidth systems. Dual polarization communication techniques are sometimes used. In a dual polarization technique, data communicated on the same frequency is communicated in separate polarized planes. Close to a doubling of communication capacity is possible through the use of dual polarization techniques. For signal energy transduction in line with a dual polarization scheme, the wireless device is required to use a dual polarized antenna, operable in separate polarization planes. The use of dual polarization techniques is also advantageous because the effects of multipath transmission and other interference are generally reduced, thereby improving signal transmission and reception quality.

A dual-polarized antenna is achievable, for example, by feeding a square patch antenna on two orthogonal edges thereof via an edge feed or a probe feed. Existing dual polarized patch antennas are generally used in conjunction with two mains supply circuits. These existing antennas suffer from several limitations. For example, it is required that the separation distances between the supply connections are large enough to prevent a coupling from occurring between the respective supply lines. Excessive amounts of coupling result in high levels of cross polarization.

As wireless devices are increasingly smaller, housed in increasingly smaller housings, problems associated with levels of cross polarization are likely to become more significant. An improved dual-polarized antenna constructed in a way to reduce these deleterious problems is needed.

It is in light of this background information relating to antennas for radio devices that the significant improvements of the present invention have been developed.

Brief Description of Drawings

Figure 1 illustrates a functional block diagram of a radio communication system in which an embodiment of the present invention is operable.

Figure 2 illustrates a plan view of a dual-polarized multiple ribbon loop antenna of an embodiment of the present invention.

Figure 3 illustrates a graphical representation showing simulated and measured return losses plotted as a function of frequency of an antenna that is part of a wireless device of an exemplary embodiment of the present invention.

Figure 4 illustrates a representation of an example simulated current distribution of an antenna of an embodiment of the present invention.

Figure 5 illustrates a graphical representation of simulated radiation patterns of an antenna of an embodiment of the present invention at 2.47 GHz.

Figure 6 illustrates a graphical representation similar to that shown in Figure 5, but of measured radiation patterns displayed by an antenna of an embodiment of the present invention at 2.47 GHz.

Figure 7 illustrates a graphical representation showing a simulated gain as a function of an antenna of an embodiment of the present invention.

Figure 8 illustrates a flowchart method representative of the method of operation of an embodiment of the present invention.

Detailed Description

The present invention, therefore, advantageously provides an antenna apparatus and an associated method for a portable radio device, such as a Bluetooth-compatible or 802.11-compatible device, which operates in the IMS (Industry, Medical Area) frequency band. and Scientific).

By operating an embodiment of the present invention, a dual-polarized antenna of compact construction is provided. The antenna is capable of positioning on or within a radio housing of the portable radio device.

In one aspect of the present invention, the antenna is formed from chemically etched loop tapes on a substrate, configured so as to be resonant to a selected frequency band, such as a frequency band located at 2.47 GHz. of dimensions that allow its placement, together with the loop tapes attacked on it, within the housing of a portable radio device, such as a wireless device operated on a Bluetooth-compatible or 802.11-compatible system. Signal energy is polarized in orthogonal or other directions. The transduced signal energy generated in the wireless device is transduced into an electromagnetic form by the antenna and propagated from there in polarized directions. And the electromagnetic energy communicated to the wireless device in the polarized directions is transduced into electrical form for subsequent operations on it by a circuit of the radio device.

In another aspect of the present invention, a first group of the loop tapes chemically attacked on the substrate is configured to form an L-corner antenna loop. The L-corner loop is formed by shaping adjacent loop tapes so that the ends of adjacent loop tapes intersect at substantially perpendicular angles. The loop tapes of the first group thus configured are all, therefore, variably positioned to extend in a first bias direction or a second bias direction, the second bias direction orthogonal to the first bias direction.

In another aspect of the present invention, a second group of tie tapes chemically etched into the substrate defines a second L-shaped corner loop. Adjacent tapes of the loop tapes are configured to be connected at their ends at substantially perpendicular angles of intersection, in this way to be of rectangular corner. And each loop tape so configured extends variably in a first bias direction or a second bias direction, orthogonal to the first bias direction. A signal energy is transduced by the second loop also in both polarization directions.

In another aspect of the present invention, the first group and the second group of bow tapes include a shared set of bow tapes, that is, bow tapes that are common to both the first group and the second group. The shared set of loop tapes is part of the first antenna loop and part of the second antenna loop. At least one of the shared set loop tapes extends in the first bias direction and at least one of the shared set loop ribbons extends in the second bias direction. And more specifically, the shared set includes at least two loop tapes extending in the first bias direction and at least one loop tape extending in the second bias direction. The loop tapes extending in the first bias direction are connected together by means of a loop tape extending in the second bias direction.

In another aspect of the present invention, a single power connection is provided for both polarization directions. The single feed connection is formed or otherwise defined in a loop tape of the shared set. The power connection is positioned to allow symmetrical excitation of the two antenna loops. Through the use of the single power connection, problems associated with cross polarization are reduced. A high-gain, high-efficiency and compact dual-polarized antenna is provided in this way.

In these and other aspects, therefore, an antenna apparatus and an associated methodology are provided for a radio device. A substrate is provided. And a first group of loop tapes is laid out on the substrate. The loop tapes of the first group are configured to form a first loop having at least one loop tape extending in a first bias direction and at least one loop ribbon extending in a second bias direction. A second group of loop tapes is laid out on the substrate. The loop ribbons of the second group are configured to form a second loop that has at least one ribbon extending in the second bias direction. The first and second groups of loop ribbons each have loop ribbons that extend in the first and second bias directions, respectively, and exhibit a dual bias operation.

Turning first, therefore, to Figure 1, a radio communication system, shown generally at 10, provides communications with a mobile station 12. The mobile station, in the example implementation, operates in line with a Bluetooth or an IEEE 802.11 (b) or (g) standard, operable for sending and receiving signals in the 2.4 GHz band. More generally, mobile station 12 is representative of any one of several wireless devices, and the system Radio communication is representative of any varied radio communication systems operable in compliance with any of the various communication standards or allowing operation in unregulated frequency bands. Therefore, although the following description describes an example operation of a Bluetooth or IEEE 802.1 compliant system operable in the 2.4 GHz frequency band, it should be understood that the following description is merely an example and that the description of operation of the radio communication system operable in accordance with another way is analogous.

The radio communication system includes a network part, here represented by a network station 14. The network station comprises, for example, an access point of a WLAN or an analogous entity that transcepts signals with wireless devices, such as as the mobile station 12. The network station which here forms an access point is part of a local area network (WLAN) structure 16 which, in turn, is coupled to an external network, here a packet data network public (PDN) 18, just like the Internet.

The operating standard in accordance with which mobile and network stations are operable is to allow and here provide dual polarized communications in the operating frequency band of the communication system, here an IMS band extending between 2.40 and 2.485 GHz .

The mobile station 12 includes a transceiver circuit, here represented by a receiving part (RX) 26 and a transmitting part (TX) 28. The receiving and transmitting parts are coupled, such as by means of an antenna coupler or another entity that provides isolation between transceiver portions for an antenna 32 of an embodiment of the present invention. The transceiver circuit is capable of dual polarization operation. That is, the transmit and receive parts are capable of generating signals for transmission in both polarization directions and also operating on signals communicated to the mobile station in both polarization directions.

Correspondingly, antenna 32 forms a dual polarized antenna capable of transducing signal energy from both polarization directions. That is, the signal energy is detected by the antenna in both polarization directions. And the signal energy generated in the mobile station is transduced in electromagnetic form and radiated in both dual polarization directions. In the exemplary implementation, antenna 32 is disposed on a generally flat substrate of dimensions that allow it to be positioned within a mobile station housing.

Figure 2 illustrates in greater detail the antenna 32 of an embodiment of the present invention and which is part of the mobile station 12, shown in Figure 1. The antenna is formed by a plurality of loop tapes 42 disposed on a substrate 44. The tapes loops are chemically etched, painted, or otherwise formed onto the substrate. The loop tapes are configured so that the loop tapes adjacent to the loop tapes abut against each other in electrical connection between them. Loop tapes are of lengths and widths and are connected together so as to be resonant in a desired frequency band, here the 2.4GHz frequency band.

The loop ribbons are arranged in a rectangular loop structure comprised of a first group 46 of loop ribbons and a second group 48 of loop ribbons. Adjacent loop ribbons intersect at their ends at substantially perpendicular intersecting angles. Groups 46 and 48 form antenna loops in which, due to the perpendicular intersecting angles of adjacent loop ribbons, the corners of the loops are L-shaped, that is, they are L-corner.

The loop ribbons of loops 46 and 48 include a shared 52 set of loop ribbons. The shared set loop tapes are shared between the groups, that is, the shared set loop tapes form parts of both groups 46 and 48.

The set shared in the example implementation and as shown includes three loop tapes, connected end to end, including two L-corner portions.

Figure 2 illustrates references 54, 56, 58, 60, 62, 64, 66 and 68. At each of these reference points, an L-shaped corner of a loop is formed. Due to the substantially perpendicular intersections of the adjacent loop ribbons, each of the loop ribbons extends in one of two polarization directions. The polarization directions are orthogonal, defined by the geometric axes 72 and 74. The geometric axis 74 defines a first polarization direction and the geometric axis 72 defines a second polarization direction. The loop tapes extending between the datums 64 and 54, between the datums 60 and 58, between the datums 62 and 68 and between the datums 66 and 56 all extend in the first bias direction. . The loop tapes extending between the datum points 64 and 62, between the datum points 62 and 60 and between the datum points 66 and 68 all extend in the second bias direction. In the example implementation and as shown, the lengths defining an outer perimeter of a rectangular configuration defined by the loop tapes are all the same. Additionally, the loop tapes defined by points 54-56, 66-72 and 62-60 are also all of corresponding lengths. And, in the example implementation, the widths of each of the loop tapes is the same width, w.

Antenna 32 includes a single feed connection 82 providing a feed connection point connectable to the transceiver circuit (shown in Figure 1) of the mobile station (shown in Figure 1). The single feed connection provides a feed which, positioned as illustrated at a midpoint of the loop tape 66-68, provides a symmetrical excitation of the loops formed from the groups 46 and 48 of loop tapes. Because only a single supply connection is needed, the problems associated with spacing requirements between multiple, conventionally required supply connections are eliminated.

The geometric configuration of the example implementation of antenna 32 shown in Figure 2 provides three parallel strips in phase in each of the polarization directions 72 and 74. The strips 54-58, 66-68 and 64-60 extend in the second direction of polarization. And the parallel strips 54-64, 58-60 and 56-66/68-62 extending in the first polarization direction allow the antenna to exhibit high gain and high efficiency.

The two groups 46 and 48 of loop tapes are chemically etched onto a printed circuit board or other substrate. Loop tapes are thought of as a combination of two electrically connected multi-L-shaped rectangular loop tapes that have a common set of shared tapes. In a further implementation, the antenna further includes a metal reflector 84 disposed in the ribbon loop opening plane, here disposed below a bottom surface of the substrate 44.

Orthogonal dual polarizing radiation is accomplished by arranging the loop tapes to extend in directions parallel to one of the geometric axes 72 or 74. The supply connection 82 located in the center of the loop tape 66-68 provides a symmetrical excitation, that mode for reducing the cross-polarization levels of the dual polarization components. The loop tapes extending in each of the polarization directions are arranged in a three-element phased array that provides high levels of gain. The direction of current, ie charge flow, during an antenna operation reverses at half-wavelength intervals due to permanent wave distributions along the tapes. Additionally, each side of the outer perimeter loop is equally divided into three sections to thereby produce a phased current distribution across all tape sections, if the length of the perimeter loop is appropriately chosen.

Figure 3 illustrates a graphical representation 92 that illustrates graphs 94 and 96 that are representative of simulated and measured return losses, respectively, plotted as a function of frequency. In the example implementation, the antenna is resonant in the 2.4GHz frequency band and the graphics are indicative of this.

Figure 4 again illustrates the antenna 32 of an exemplary embodiment of the present invention. Here, a simulated current distribution displayed by the antenna at its resonant frequency of 2.47 GHz. The cross parts of the antenna represent the current in the antenna. An analysis of the current distribution indicates that the current distribution is in directions parallel to the geometric polarization axes 72 and 74 shown in Figure 2.

Figures 5 and 6 illustrate, respectively, two-dimensional radiation patterns, simulated and measured, respectively, of the antenna 32 of an embodiment of the present invention at its resonant frequency of 2.47 GHz. In each representation, representations in plane of zero and ninety degrees 102 and 104 are plotted.

Figure 7 illustrates a graphical representation 106 illustrating a simulated gain as a function of frequency displayed by antenna 32 of an embodiment of the present invention. The gain is centered at or near the resonant frequency of 2.47 GHz.

Figure 8 illustrates a method flowchart, shown generally at 112, representative of the method of operation of an embodiment of the present invention. The method is for transducing signal energy in a radio device.

First, and as indicated by block 114, a first group of loop tapes is disposed on a substrate. The loop ribbons of the first group are configured to form a first loop having at least one ribbon extending in a first bias direction and at least one ribbon extending in a second bias direction. And, as indicated by block 116, a second group of loop tapes is disposed on the substrate. The loop ribbons of the second group are configured to form a second loop having at least one ribbon extending in the first bias direction and at least one ribbon extending in the second bias direction.

Once formed on the substrate, loop tapes are used for signal energy transduction, polarized in the polarization direction and in the second polarization direction, in the first and second groups, respectively, of the loop tapes.

In this way, a dual-polarized antenna of compact dimensions is provided. Through the use of loop tapes arranged on a substrate, configured to allow the use of a single feed connection for symmetrical antenna excitation, thus configured, the problems associated with multi-feed connections used by polarized antennas are eliminated conventional doubles.

Claims (6)

1. Antenna apparatus (32) for a radio device characterized in that it comprises: a substrate (44) having opposite top and bottom surfaces; a plurality of loop tapes (42) disposed on the top surface of the said substrate (44), each loop tape disposed in electrical contact with at least one adjacent loop tape and configured in an arrangement having: a closed rectangular structure including: a first side loop tape (64-54) and a second tape of side loop tapes (60-58) disposed opposite said first side loop tape and each of said first and second side loop tapes of equal dimensions and extending in a first bias direction (74), and third loop tape side (54-56-58) and fourth side loop tape (60-62-64) disposed opposite said third side loop tape and each of said third and fourth side loop tapes of equal dimensions and extending in a second polarization direction (72) orthogonal to said first direction of bias, said third side loop tape including a third side loop tape portion (54-56) extending a length from said first side loop tape and said fourth side loop tape. side loop including a fourth side loop tape portion (60-62) extending said length from said second side loop tape; and a plurality of shared loop tapes (52) disposed within the perimeter of said closed rectangular structure including: a first shared tape extending in said first bias direction (74) and having a first end (56) in direct current coupled to the said third side loop tape portion in said length from said first side loop tape, a second shared tape extending in said first bias direction (74) and having a first end (62) in direct current coupled to the said fourth side loop tape portion in said length from said second side loop tape, and a shared third tape having said length extending in said second bias direction (72) and direct current coupled to a second end (66) of said first shared tape and direct current coupled to a second end (68) of the r Said second shared tape, wherein said side and shared loop tapes define two symmetrical antenna loops (46, 48) within said closed rectangular structure, wherein a first antenna loop (46) comprises said plurality of antenna loops (46, 48) shared loop (52), said portion of third side loop tape (54-56), said first side loop tape (54-64), and said fourth side loop tape (62-64) absent from said fourth side loop tape portion (60-62) and a second antenna loop (48) comprises said plurality of shared loop tapes (52), said fourth side loop tape portion (60-62), the said second side loop tape (58-60), and said third side loop tape (56-58) absent from said third side loop tape portion (54-56); and a single feed connection coupled to said third shared tape at a feed point (82) disposed midway between said second end (66) of said first shared tape and said second end (68) of said second shared tape for provide simultaneous symmetrical excitation of the antenna loops. 2. Antenna apparatus (32) according to claim 1, characterized in that said loop tapes of said first antenna loop (46) are concatenated to a resonant loop length in a frequency band of 2 .4 GHz and said loop tapes of said second antenna loop (48) are concatenated to a resonant loop length in said 2.4 GHz frequency band. Antenna apparatus (32) according to claim 1, characterized in that the first antenna loop (46) forms a first L-shaped antenna loop and the second antenna loop (48) forms a second L-shaped antenna loop, said first and second L-shaped antenna loops each having their respective loop ribbons concatenated in a resonant loop length in an ISM, Industrial, Scientific and Medical frequency band. 4. Method (112) for transducing a signal energy from a radio device (12), said method characterized in that it comprises the operations of: arranging (114) of a plurality of loop tapes (42 ) in a closed rectangular structure on a top surface of a substrate (44) having opposite top and bottom surfaces, including: arranging a first side loop tape (6454) and a second side loop tape (60- 58) opposite said first side loop tape, each of said first and second side loop tapes extending in a first bias direction (74) and having equal dimensions, and third side loop tape arrangement (54-56- 58) and fourth side loop tape (60-62-64) opposite said third side loop tape, each of said third and fourth side loop tapes extend in a second bias direction (72) orthogonal to said first polarization direction and having dimension are equal, said third side loop tape arrangement including the arrangement of a third side loop tape portion (54-56) extending a length from said first side loop tape and said arrangement of said fourth side loop tape. side loop including arranging a portion of fourth side loop tape (60-62) extending said length from said second side loop tape; arranging a plurality of shared loop tapes (52) within the perimeter of said closed rectangular structure including: direct current coupling of a first shared tape extending in said first bias direction (74) and having a first end (56) to said third side loop tape portion in said length from said first side loop tape, direct current coupling of a second shared tape extending in said first pole direction tying (74) and having a first end (62) to said fourth side loop tape portion in said length from said second side loop tape, and direct current coupling of a third shared tape having said length, extending in said second bias direction (72) to a second end (66) of said first shared tape and to a second end (68) of said second shared tape, wherein said shared side loop tapes define two antenna loops symmetrical within said closed rectangular structure; wherein said plurality of shared loop tapes (52), said third side loop tape portion (54-56), said first side loop tape (54-64), and said fourth side loop tape (62-64) absent from said fourth side loop tape portion (60-62) create a first antenna loop (46) and said plurality of loop tapes (52), said portion of fourth side loop tape (60-62), said second side loop tape (58-60), and said third side loop tape (56-58) absent from said portion of third side loop tape (54-56) create the second antenna loop (48); provision of a signal power feed at a single feed connection on said third tape shared at a feed point (82) arranged to midway between said second end (66) of said first shared tape and said second end (68) of said second shared tape, thus providing symmetrical excitation of the antenna loops; and transducing (118) of signal energy from loop tapes that are polarized in the first direction (74) and simultaneously transducing (118) of signal energy from loop tapes that are polarized in the second direction (72 ). 5. Method (112) according to claim 4, characterized in that it further comprises the operation of supplying signal power to the single power connection (82). 6. Method (112) according to claim 4, characterized in that it further comprises the operation of exciting the first antenna loop (46) and the second antenna loop (48) with the signal energy.

Images