The present invention relates to an antenna suitable to be integrated in a printed circuit board, which is an electromagnetically coupled antenna that comprises:
Such electromagnetically coupled antennas have an interesting, basic design to consider these for integration in a printed circuit board (PCB) for routers and top boxes that may be used in Wi-Fi applications. In order to achieve the most feasible integration of the antenna in a PCB board, a general urge exists in the field to miniaturize the electromagnetically coupled antenna as much as possible, while retaining sufficient radiation properties.
Apart from a reduced size of the antenna making integration in a PCB more feasible, any successful step in miniaturization may contribute to a further reduced coupling effect, and more uniform radiation patterns. Furthermore, such may result in higher throughput levels.
In order to accomplish a further miniaturization of the electromagnetically coupled antenna, it is a requisite that the antenna shall be improved in regard of at least one of two crucial properties:
As a general rule, a larger FBW value results in an improved antenna performance in regard of its margins. Conversely, a reduction of the IRC value is required to achieve an improved antenna performance. If one value, or preferably both values are improved, the antenna as a whole may be dimensioned smaller, thus achieving a further miniaturization.
The general objective of improving the antenna by the above two properties, can be quantified by the objective function (OF) which is the ratio of FBW divided by IRC. Accordingly, a larger OF indicates a better performance of the antenna. The OF value shall be used as a yard stick in this description to determine to what extent the antenna performance is improved.
The present invention meets the above general objective, by the provision of:
An antenna suitable to be integrated in a printed circuit board, which is an electromagnetically coupled antenna that comprises:
In regard of the above definition, the following terms are further explained:
It was found by the inventors that the above antenna allows for a further miniaturization, because the FBW value is raised by its novel design. Furthermore, the IRC value is reduced by the invention.
It is preferred that the antenna according to the invention is further provided with an additional body of dielectric material which covers the T-shaped slot in the top metallized layer. The additional body may be flat and thin, and hence have the form of a chip, preferably made out of polymer or glass. The additional body thus functions, also, as dielectric load of the antenna.
It was found that the advantageous effects of the antenna could be further enhanced by virtue of the additional body.
It is further preferred in the antenna according to the invention, that the contour of the T-shaped slot in the top metallized layer is composed of two longitudinal slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot.
The T-shaped slot is thus not limited to the classical capital T form or contour, but is more generally based on two connecting longitudinal slots of which the longitudinal axis have an orthogonal orientation towards each other. The longitudinal slots may be rectangular slots, rounded forms (e.g. elliptic forms), or more intricate versions thereof (e.g. multi-lobed and/or multi-cornered forms).
In the context of the invention, the term horizontally and vertically are merely used as relative terms in order to express the relative orientation, which is orthogonal to each other. The terms should not be understood as having an additional, or absolute meaning.
Preferably in the antenna according to the invention, the distance between adjacent strands in a row is in the range of 1 up to 2 times the thickness of a single strand.
A practically appropriate thickness of the body of dielectric material may lie in the range of 0.6 to 1.0 mm, for instance about 0.8 mm.
According to a first particular aspect of the invention, the antenna is suitable to be used in the WiFi frequency range of 4.9 GHz up to 6 GHz. This range is also hereafter referred to as a 5 GHz frequency band, and the antenna as a ‘5G antenna’.
The following, preferred features of the invention are in particular useful for that frequency range.
In addition, the next described, preferred features of the invention relating to the T-shaped slot, are in particular useful in the frequency range above:
Further it is preferred in the antenna according to the invention, that the contour of the T-shaped slot in the top metallized layer is composed of two slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot,
wherein:
In this context of defining the contours by formula, the contour of the second, vertically oriented slot may be a truncated form of the slot as defined by the formula. Accordingly, the contour of the second slot is a segment of the contour as defined by the formula. This truncation is done for dimensional reasons, in order to adapt the vertical length of the second slot.
The formula above is also known as a ‘superformula’ and the contours defined by it as ‘supershapes’, the underlying theory has been developed by J. Gielis, and has been described in several scientific articles as well as in U.S. Pat. No. 7,620,527.
In order to compose a T-shape with the form of a classical capital T, the T-shaped slot is composed of the contours according to the above formula,
In particular, it is preferred that in the antenna which has a T-shaped slot composed of the contours according to the above formula, the following parameters are applied
Such an antenna is referred to as having an optimal impedance matching (OIM) configuration.
Further in particular, it is preferred that in the antenna which has a T-shaped slot composed of the contours according to the above formula, the following parameters are applied
Such an antenna is referred to as having an ultra-wideband (UWB) configuration.
For the antenna suitable in the 5 GHz frequency range, some preferred dimensions are:
Width of the feeding line between 0.25 and 2.0 mm.
The width of the feeding line is optimized in order to achieve enhanced impedance matching characteristics to 50 Ohm of the antenna element across the entire frequency band of operation.
According to a second particular aspect of the invention, the antenna is suitable to be used in the WiFi frequency range between 2.4 and 2.5 GHz. This range is also hereafter referred to as a 2.4GHz frequency band, and the antenna as a ‘2G antenna’.
The following, preferred features of the invention are in particular useful for that frequency range:
In regard of the feeding line of a G-shape, the following dimensions are preferred:
The width of the feeding line is optimized in order to achieve enhanced impedance matching characteristics to 50 Ohm of the antenna element across the entire frequency band of operation.
In addition, the next described, preferred features of the invention relating to the T-shaped slot, are in particular useful in the frequency range of 2.4 GHz to 2.5 GHz:
Further it is preferred in the antenna according to the invention, that the contour of the T-shaped slot in the top metallized layer is composed of two slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot,
wherein:
In this context of defining the contours by formula, the contour of the second, vertically oriented slot may be a truncated form of the slot as defined by the formula. Accordingly, the contour of the second slot is a segment of the contour as defined by the formula. This truncation is done for dimensional reasons, in order to adapt the vertical length of the second slot.
The formula above is also known as a ‘superformula’ and the contours defined by it as ‘supershapes’, the underlying theory has been developed by J. Gielis, and has been described in several scientific articles as well as in U.S. Pat. No. 7,620,527.
In order to compose a T-shape with the form of a classical capital T, the T-shaped slot is composed of the contours according to the above formula,
wherein the contours of the first and second slot are each defined by the additional conditions:
In particular, it is preferred that in the antenna which has a T-shaped slot composed of the contours according to the above formula, the following parameters are applied:
Such an antenna is referred to as having an optimal impedance matching (OIM) configuration.
Further in particular, it is preferred that in the antenna which has a T-shaped slot composed of the contours according to the above formula, the following parameters are applied:
Such an antenna is referred to as having a broadband (BB) configuration.
For the antenna suitable in the 2.4-2.5 GHz frequency range, some preferred dimensions are:
In another aspect, the invention relates to a printed circuit board which is provided with an antenna according to the invention, wherein a part of the board, and preferably a part of the circumferential edge of the board, constitutes the body of dielectric material of the antenna.
The invention will be further elucidated by the appended figures in which:
This first preferred type of the antenna, is suitable to be used in the frequency range between 4.9 and 6.0 GHz, and may be referred to as 5G antenna.
The second preferred type differs from the first, in that a slot to be provided on the bottom metallized layer is not shown, but is actually identical to the T-shaped slot 3. Further, the strands are positioned in a more intricate pattern, and the feeding line 7B is of a G-shape. The chosen dimensions of the second type antenna are also different over the first type.
This second preferred type of the antenna, is suitable to be used in the frequency range between 2.4 and 2.5 GHz, and may be referred to as 2G antenna.
The whole assembly 36 constitutes an antenna according to the invention, which is complemented with an additional body 1 on the top side to further enhance the antenna characteristics.
In
The contour of the T-shaped slot 3 in the top metallized layer is composed of two slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot,
The contour of the T-shaped slot 3 in the top metallized layer is composed of two slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot,
The contour of the T-shaped slot 3 in the top metallized layer is composed of two slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot,
wherein the contours of the first and second slot are each defined by the superformula according to appended claim 22 with the parameters of appended claim 23.
The contour of the T-shaped slot 3 in the top metallized layer is composed of two slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot,
wherein the contours of the first and second slot are each defined by the superformula according to appended claim 22 with the parameters of appended claim 24.
The contour of the T-shaped slot 3 in the top metallized layer has the form of a classical capital T, and is composed of two slots of which a first slot forms a horizontally oriented slot of which the middle part is connected to the top end of a second slot which forms a vertically oriented slot,
wherein the contours of the first and second slot are each defined by the superformula according to claim 22,
and by the additional conditions:
Radiation properties of several antennas within the realm of the invention were measured. The antennas measured cover both the first and second types, with various T-shaped slots on the metallized layer.
Group 1; “5G Antenna”
Of the first preferred type of the antenna of the general design given in
Type 5G.1 “optimal impedance matching configuration”
The general design of
Type 5G.2 “ultra wide band configuration”
The general design of
Type 5G.3 “classical T-shape”
The general design of
The table below shows the radiation properties for the three 5G antenna types.
All the above three 5G antenna types have attractive properties in terms of their radiation properties, and OF value (the ratio of FBW divided by IRC).
Within this group of 5G antennas, the supershaped T-shaped slots of the 5G.1 and 5G.2 configurations are most attractive in terms of OF value.
Group 2, “2G antenna”
Of the second preferred type of the antenna of the general design given in
Type 2G.1 “optimal impedance matching configuration”
The general design of
Type 2G.2 “broadband configuration”
The general design of
Type 2G.3 “classical T-shape”
The general design of
The table below shows the radiation properties for the three 2G antenna types.
All the above three 2G antenna types have attractive properties in terms of their radiation properties, and OF value (the ratio of FBW divided by IRC).
Within this group of 2G antennas, the supershaped T-shaped slot of the 2G.1 configuration is most attractive in terms of OF value.
Number | Date | Country | Kind |
---|---|---|---|
20170100395 | Aug 2017 | GR | national |
2019472 | Aug 2017 | NL | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/NL2018/050560 | 8/30/2018 | WO | 00 |