JP4417395B2 - Radio communication antenna apparatus and radio communication method - Google Patents

Description

  The present invention relates to an antenna device for wireless communication and a wireless communication method for expanding communication capacity by transmitting and receiving different signals using a plurality of power feeding antennas or a plurality of receiving antennas.

Conventionally, various radio communication antennas having a plurality of antenna elements are used in MIMO transmission and the like.
As these radio communication antennas, for example, the following two antennas are known.
A first example is a radio communication antenna using two orthogonal notch antennas and inverted F antennas (see, for example, Non-Patent Document 1).
FIG. 10 is a perspective view showing a radio communication antenna using a notch antenna and an inverted F antenna.
The wireless communication antenna 900 includes a rectangular dielectric substrate 901. The ground plate on the upper surface of the dielectric substrate 901 is provided with two notch antennas 910 and 920 each having an open end at each of the short side and the long side. The angle between these two notch antennas 910 and 920 is 90 degrees.

In addition, a modified inverted F antenna 930 is provided near the tip of one notch antenna 910. The modified inverted-F antenna 930 includes a feed pin 931 and a short-circuit pin 932 that are perpendicular to the dielectric substrate 901, and an H-shaped conductor plate 933 that is disposed so as to contact the tops of the feed pin 931 and the short-circuit pin 932. Is done.
A protrusion 934 parallel to the dielectric substrate 901 is provided at the center of the H-shaped conductor plate 933, and a power feed pin 931 and a short-circuit pin 932 are connected to the protrusion 934.
The two notch antennas 910 and 920 and the modified inverted F antenna 930 are fed by a microstrip line provided on the back surface of the dielectric substrate 901. The two notch antennas 910 and 920 have a radiation characteristic having a main polarization as horizontal polarization, and these two notch antennas 910 and 920 are arranged at right angles to each other, so that the radiation patterns are orthogonal. .
Further, since the modified inverted F antenna 930 is mainly radiated by the feed pin 931 perpendicular to the main surface of the dielectric substrate 901, a radiation characteristic having a vertically polarized wave as the main polarized wave can be obtained.
Thus, by combining antennas having orthogonal directivity and polarization, low inter-element coupling is realized, radiation efficiency is improved, and SNR (signal-to-noise ratio) characteristics are improved.

The second example is an antenna for wireless communication in which a waveguide element is shared between two Yagi / Uda arrays.
FIG. 11 is a diagram showing an antenna for wireless communication in which a waveguide element is shared between Yagi and Uda arrays. An upper diagram is a plan view, and a lower diagram is a circuit configuration corresponding to the plan view. It is a circuit block diagram which shows a mode seen from the side surface.
The wireless communication antenna 900a includes a rectangular dielectric substrate 901a. A ground 902 is provided on the lower surface of the dielectric substrate 901a. In addition, square-shaped feeding antenna elements 941 and 942 are provided on both ends of the dielectric substrate 901a in the longitudinal direction.

Between the feeding antenna elements 941 and 942, a square parasitic parasitic antenna element 950 smaller in size than the feeding antenna elements 941 and 942 is provided. A plurality of parasitic antenna elements 950 are arranged in the longitudinal direction of the dielectric substrate 901a. The parasitic antenna element 950 is electrically smaller than the feeding antenna elements 941 and 942.
Further, the wireless communication antenna 900a includes power supply means 961 and 962 for supplying power and termination means 971 and 972.
One end of the power supply means 961 is connected to the power supply antenna element 941, and the other end is fixedly connected to the ground 902. In addition, one end of the power feeding means 962 is connected to the power feeding antenna element 942, and the other end is fixedly connected to the ground 902.
One end of the termination means 971 is connected to the feeding antenna element 941, and the other end is fixedly connected to the ground 902. One end of the termination means 972 is connected to the power supply antenna element 942, and the other end is fixedly connected to the ground 902. That is, the feed antenna element 941 is selectively connected to the feed means 961 or the termination means 971, and the feed antenna element 942 is selectively connected to the feed means 962 or the termination means 972. It has become.

Under such a configuration, one of the feeding antenna elements is connected to the feeding means, and the other feeding antenna element is connected to the termination means. For example, the feeding antenna element 941 is connected to the feeding means 961, and the feeding antenna element 942 is connected to the termination means 972. When the feeding antenna element 941 is fed, power is radiated from the feeding antenna element 941 as a radio wave, and this radiated power is transmitted through the parasitic antenna element 950 as a waveguide. That is, the feed antenna element 941 and the parasitic antenna element 950 operate as a Yagi / Uda array and are radiated from the feed antenna element 942 toward the parasitic antenna element 950.
In addition, by selectively switching the connection of the power supply antenna elements 941 and 942 to the power supply means 961 and 962 or the termination means 971 and 972 by the switches 981 and 982, two beams having high directivity can be obtained. You can switch to one direction. Thereby, the SNR characteristic can be improved by directing in the direction in which the counterpart wireless station exists.
Naoki Honma, Masaaki Ida, Kentaro Nishimori, Yasushi Takatori, Koichi Tsunekawa, “Proposal of a small 3-port MIMO antenna using a modified inverted-F antenna and a notch antenna”, Society Conference of IEICE, B-1-230, September 2005

However, as in the first example, when an antenna having orthogonal directivity and polarization is arranged in a small wireless communication terminal, a large number of independent antennas are arranged close to each other. There is a problem that the degree of freedom becomes small. Therefore, it is difficult to shape the directivity, and the directivity cannot be controlled so as to optimize the MIMO communication capacity, for example.
In addition, when the parasitic antenna elements are arranged in a row between the feeding antenna elements as in the second example, the directivity gain in a specific direction increases, but the coupling between the feeding antenna elements increases. When the antenna element is terminated with a resistive termination element, there is a problem that the antenna radiation efficiency is greatly deteriorated. Therefore, in an environment where a desired signal arrives from the surroundings toward the antenna, the SNR characteristic deteriorates and the communication capacity decreases.

  The present invention has been made in view of such circumstances, and can reduce the antenna coupling between a plurality of feed antenna elements and improve the S / N ratio, or the spatial correlation between the feed antenna elements. It is an object of the present invention to provide a radio communication antenna apparatus and a radio communication method that can reduce communication and increase communication capacity.

In order to solve the above problems, the present invention provides the following means.
The present invention is a wireless communication antenna device in which a plurality of antenna elements having the same polarization characteristics are arranged in a row, and among the antenna elements arranged in a row, The antenna elements at both ends are feeding antenna elements, the remaining antenna elements arranged between the feeding antenna elements at both ends are parasitic antenna elements, and the parasitic antenna elements are terminated by reactance elements. The reactance values of the reactance elements are all set equal in the column, and are set to values that maximize the expected value of communication capacity in wireless communication.

Further, the present invention is an antenna device in which antenna elements having both two orthogonal polarization characteristics are arranged in rows, and among the antenna elements arranged in rows, The antenna elements at both ends of the row are feeding antenna elements having independent feeding means corresponding to two orthogonal polarizations, and the remaining antenna elements arranged between the feeding antenna elements at both ends are: A parasitic antenna element terminated by an independent reactance element corresponding to each of two orthogonal polarizations, and the reactance values of the reactance elements are all set equal in the columns corresponding to the respective polarizations, It is set to a value that maximizes the expected value of communication capacity in wireless communication.

  According to a second aspect of the present invention, there is provided the antenna device for wireless communication according to claim 2, further comprising switching means for selectively feeding power to one of two orthogonal ports of the feeding antenna element. To do.

In the present invention, parasitic antenna elements having both two orthogonal polarization characteristics are arranged in rows, and feed antenna elements whose polarization directions are variable are provided at both ends of the rows. In the antenna device, the parasitic antenna element is terminated by an independent reactance element corresponding to each of two orthogonal polarizations, and a reactance value of the reactance element corresponds to each of the polarizations All of the columns are set to be equal and set to a value that maximizes the expected value of the communication capacity in wireless communication.

Further, the present invention is the radio communication antenna apparatus according to any one of claims 1 to 4, wherein a longitudinal direction in a row of the plurality of antenna elements is a horizontal direction and a thickness direction is a vertical direction. The reactance value of the reactance element is set so that the electrical length of the parasitic antenna element is shorter than that of the feed antenna element.
The present invention is the radio communication antenna apparatus according to any one of claims 1 to 5, wherein the reactance values of the plurality of antenna elements are sequentially changed from a low value to a high value. A second signal processing unit that selects a reactance value that provides the highest SNR characteristic, or that selects a combination of reactance values of the plurality of antenna elements that provides the highest channel capacity. To do.
Further, the present invention is the radio communication antenna device according to any one of claims 1 to 6, wherein the reactance value of the reactance element is a combination of polarization of the base station antenna, the number of elements, Or, it is a signal including electrical characteristic information that is information on the element spacing, and based on the electrical characteristic information included in the signal received from the base station antenna device, the expected value of the communication capacity in wireless communication is maximized. It is set to a value to be converted.
Further, the present invention is the radio communication antenna apparatus according to any one of claims 1 to 7 , wherein the reactance value of the reactance element is variable, and the maximum communication is possible at an arbitrary place or time. A setting means for setting a reactance value for obtaining a capacity is provided.

In addition, the present invention is used as a terminal device in a wireless communication system, and is the wireless communication antenna device according to any one of claims 1 to 8 , wherein a plurality of wireless communication antenna devices are simultaneously the same. When performing spatial multiplexing using frequencies, a reactance value is set such that the average value of the communication capacities of all wireless communication antenna devices is maximized.

Further, the present invention is a radio communication antenna device according to any one of claims 1 to 9, wherein the radiating antenna element, the loss due to inter-element coupling that occurs between the radiating antenna element Power is supplied through a decoupling circuit that improves the above.

Further, the present invention is a radio communication antenna apparatus in which a plurality of antenna elements having the same polarization characteristics are arranged in a row, and among the antenna elements arranged in a row, The antenna elements at both ends of the row are feeding antenna elements, the remaining antenna elements arranged between the feeding antenna elements at both ends are parasitic antenna elements, and the parasitic antenna elements are terminated by reactance elements. And the reactance value of the reactance element is set to a value that maximizes an expected value of the communication capacity in wireless communication, and is a wireless communication method in a wireless communication antenna device , wherein the reactance element includes a plurality of transmission antenna elements device sent from the polarization of the combination of the transmitting antenna element, the number of elements, or receives a signal containing the electrical characteristic information is information element spacing The electrical characteristic information from said received signal taken out, by using the electrical characteristic information retrieved, the reactance value of the reactance element, and sets all equal in the row.

  According to the present invention, by appropriately providing the reactance value, it is possible to reduce the antenna coupling between the plurality of feeding antenna elements and improve the SN ratio, or to reduce the spatial correlation between the feeding antenna elements. Thus, the communication capacity can be increased.

(Embodiment 1)
Hereinafter, a radio communication antenna apparatus according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a radio communication antenna apparatus as a first embodiment of the present invention.
The wireless communication antenna device 1 includes a rectangular dielectric substrate 9. On the upper surface (one main surface) of the dielectric substrate 9, feed antenna elements 11 and 12 are provided at both ends in the longitudinal direction L thereof. The feeding antenna elements 11 and 12 are linearly extended in the thickness direction T of the dielectric substrate 9. The feeding antenna elements 11 and 12 are provided with feeding means 7 and 8 for supplying power independently. A plurality of parasitic antenna elements 21, 22, 23, and 24 that are linearly extended in the thickness direction T are provided between the feeding antenna elements 11 and 12. The plurality of parasitic antenna elements 21 to 24 are arranged in the longitudinal direction L of the dielectric substrate 9. The parasitic antenna elements 21 to 24 are terminated by reactance elements 31, 32, 33, and 34, respectively.

  The reactance values X1, X2, X3, and X4 of the reactance elements 31 to 34 are set to optimum values according to the environment in which the wireless communication antenna device 1 is used. That is, the use environment of the radio communication antenna apparatus 1 is assumed in advance, and for example, an optimum reactance is attached in advance at the time of manufacture. A method for determining the optimum values of the reactance values will be described later.

Next, the operation of the radio communication antenna apparatus 1 according to the present embodiment configured as described above will be described.
When signal transmission / reception is performed using both the feeding antenna elements 11 and 12, the communication capacity is greatly affected by the propagation environment.
Therefore, reactance values X1 to X4 are determined as follows.
For example, in an environment where signal waves arrive with almost equal probability from any direction around the wireless communication antenna device 1, the radiation efficiency of the feeding antenna elements 11 and 12 predominantly affects the communication capacity. Therefore, in such an environment, the reactance values X1 to X4 are determined so that the mutual coupling between the feeding antenna elements 11 and 12 is the lowest. For example, when all the reactance values X1 to X4 are set to be equal, a symmetric radiation pattern is obtained by the feeding antenna element 11 and the feeding antenna element 12.

  On the other hand, in an environment where the distribution of the arrival wave direction is biased such that the arrival wave is observed only from a limited direction, for example, the longitudinal direction L is the horizontal direction, the thickness direction T is the vertical direction, and the arrival wave is from the horizontal direction. In an environment that mainly arrives, the reactance values X1 to X4 are determined so that the electrical lengths of the parasitic antenna elements 21 to 24 are shorter than the fed antenna elements 11 and 12. As a result, the wireless communication antenna device 1 operates as a Yagi-Uda array using the parasitic antenna elements 21 to 24 as a director. For this reason, when power is supplied to the power supply antenna element 11, radio waves are radiated from the power supply antenna element 11, and the radiation pattern (the reception pattern is equal to the transmission pattern) is a direction from the power supply antenna element 11 toward the power supply antenna element 12 ( The shape has a peak in the endfire direction. The same applies when power is supplied to the power supply antenna element 12, and a radiation pattern having a peak in the direction from the power supply antenna element 12 toward the power supply antenna element 11 is obtained.

  Note that, in an indoor environment (when the transmission antenna is arranged indoors), generally, the most incoming waves from the horizontal direction are observed as viewed from the indoor terminal station. When the direct wave is removed, the signal wave arrives almost uniformly from the periphery of the dielectric substrate 9. For example, the terminal station is placed in an environment where the bottom of the housing is placed horizontally, such as a small notebook personal computer, and the horizontal orientation is placed randomly. In the past, it has been difficult to achieve a high directivity gain in the horizontal plane.

In such a case, even if the radiation pattern is shaped, the SNR does not change, but if the antenna gain in the vertical direction with a low possibility of reception can be reduced, the antenna gain in the horizontal direction can be increased. , SNR can be improved.
According to the wireless communication antenna device 1 of the present embodiment, by operating as a Yagi-Uda array, the radiation pattern on the vertical plane is narrowed, and as a result, the horizontal average directivity gain increases. That is, according to the radio communication antenna device 1, the vertical radiation pattern can be formed, and as a result, the horizontal average gain can be improved. Further, by improving the average gain, the SN ratio (signal to noise ratio) can be improved, and the communication capacity can be increased.

As described above, according to the wireless communication antenna device 1 of the present embodiment, the antenna coupling between the feeding antenna element 11 and the feeding antenna element 12 can be reduced by appropriately providing the reactance values X1 to X4. . Therefore, it is possible to improve the S / N ratio in an environment where signal waves arrive with almost equal probability from any direction.
Moreover, the spatial correlation between the feeding antenna element 11 and the feeding antenna element 12 can be reduced by appropriately giving the reactance values X1 to X4. Therefore, the communication capacity can be increased. In this embodiment, the parasitic antenna elements 21 to 24 are shared between the two Yagi / Uda arrays, so even a small terminal can realize a high S / N ratio and a low spatial correlation, and a high communication capacity. Can be realized.

In this embodiment, the reactance values X1 to X4 are set in advance. However, the present invention is not limited to this, and can be changed as appropriate. For example, the reactance elements 31 to 34 may be electronically controlled variable reactances, and may be automatically calculated and set by a control unit (setting unit) (not shown) according to the usage situation. Further, the reactance elements 31 to 34 may be provided with a change mechanism (setting means) for changing the reactance value by a dial or the like, and the user or the like may set an appropriate reactance value according to the use situation.
In this embodiment, the number of parasitic antenna elements is eight, but this effect can be obtained even when the number of parasitic antenna elements is smaller or larger.

(Embodiment 2)
Next, a second embodiment of the present invention will be described.
FIG. 2 conceptually shows the second embodiment of the present invention.
2, the same parts as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and only the differences will be described here.
In FIG. 2, the X axis, the Y axis, and the Z axis indicate axes that are orthogonal to each other, and the X axis direction coincides with the longitudinal direction W (shown in FIG. 1) of the dielectric substrate 9. The axial direction corresponds to the short direction of the dielectric substrate 9, and the Z-axis direction corresponds to the thickness direction T (shown in FIG. 1) of the dielectric substrate 9.

In the present embodiment, feed antenna elements 13 and 14 extending in the Y-axis direction are provided in the vicinity of the feed antenna elements 11 and 12 extending in the Z-axis direction, respectively. That is, the feeding antenna elements 11 and 12 and the feeding antenna elements 13 and 14 are orthogonal to each other.
Also, parasitic antenna elements 25, 26, 27, and 28 extending in the Y-axis direction are provided in the vicinity of the parasitic antenna elements 21 to 24 extending in the Z-axis direction. That is, the parasitic antenna elements 21 to 24 and the parasitic antenna elements 25 to 28 are orthogonal to each other. The parasitic antenna elements 21 to 28 are arranged in the X-axis direction between the feeding antenna elements 11 and 13 and the feeding antenna elements 12 and 14.
The parasitic antenna elements 25 to 28 are terminated by reactance elements 35, 36, 37, and 38, respectively.

The feeding antenna elements 13 and 14 and the parasitic antenna elements 25 to 28 are horizontally polarized antennas, and two radiation characteristics can be obtained by feeding the two feeding antenna elements 13 and 14. This is the same operation as the vertically polarized feed antenna elements 11 and 12 and the parasitic antenna elements 21 to 24.
Further, by appropriately setting the reactance values X5, X6, X7, and X8 of the reactance elements 35 to 38 as in the first embodiment, a high communication capacity can be obtained.
As described above, according to the wireless communication antenna device 1a in the present embodiment, the number of antenna ports is doubled by using the horizontal polarization element in addition to the vertical polarization element. A communication capacity of about double can be realized by slightly increasing the antenna size from the wireless communication antenna apparatus 1 of FIG.

Here, the characteristic evaluation result by numerical analysis will be described in the case where the wireless communication antenna device 1a is used as a terminal station.
FIG. 3A is an explanatory diagram illustrating an indoor environment in which numerical analysis is performed. The width dimension (dimension in the X-axis direction) of the rectangular parallelepiped room is 12 m, the depth dimension (dimension in the Y-axis direction) is 15 m, and the height dimension (dimension in the Z-axis direction) is 3 m. The walls will be made of concrete, and the environment will be free of fixtures.
The base station AP is installed near the corner of the room at the coordinate position (X, Y, Z) = (8, 10, 12) when the intersection point of the X axis, Y axis and Z axis is the origin O. Shall be.
Furthermore, the terminal UT is assumed to be randomly arranged on the XY plane with a height of 1 m (Z = 1).
The image wave source method was used for analysis, and the number of reflections was 10 times. The operating frequency was 4.85 GHz. The base station AP is an 8-element linear array (16 ports) of a vertical / horizontal shared antenna, and the array length is 7 wavelengths.

FIG. 3B shows the result of obtaining the expected value of the channel capacity with respect to the reactance values of the reactance elements 31 to 38, and is a graph shown in comparison with the result when no parasitic antenna element is provided.
The reactance values X1 to X2 in the parasitic antenna elements 21 to 24, which are vertical polarization elements, are all set equal to X1 = X2 = X3 = X4 = a1. The reactance values X4 to X5 in the parasitic antenna elements 25 to 28 that are horizontal polarization elements were also set to be equal to X4 = X5 = X6 = X7 = a2.
It can be seen from the graph that there is a relatively steep maximum value with respect to the reactance value a1, and a gradual change with respect to the reactance value a2. This confirms that the effect of optimizing the vertical polarization element is great.
The maximum value was (a1, a2) = (3.0Ω, 573Ω), and the channel capacity at that time was 8.4 Bits / s / Hz. When there is no parasitic antenna element, it is 6.2 Bits / s / Hz. When there is a parasitic antenna element, a channel capacity higher by about 30% or more than that without a parasitic antenna element can be obtained. I understood.

(Embodiment 3)
Next, a third embodiment of the present invention will be described.
FIG. 4 shows a third embodiment of the present invention.
In FIG. 4, the same components as those shown in FIGS. 1 to 3 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the second embodiment have the same basic configuration, and only the differences will be described here.

  The wireless communication antenna device 1b according to the present embodiment includes signal switching means 41 and 42 that selectively switch signals. One terminal 41a, 42a of the signal switching means 41, 42 is connected to the feeding antenna elements 11, 12, respectively, and the other terminal 41b, 42b is connected to the feeding antenna elements 13, 14, respectively. The fixed terminals 41c and 42c of the signal switching means 41 and 42 are connected to power supply means 7a and 8a for supplying power, and the power supply means 7a and 8a are connected to the ground G.

Under such a configuration, either the horizontally polarized wave or the vertically polarized wave feeding antenna elements 11 to 14 are selected by the signal switching means 41 and 42. For example, the feed antenna elements 11 to 14 that can obtain the highest SNR characteristics are selected, or the combination of the feed antenna elements 11 to 14 that can obtain the highest channel capacity is selected.
When the reactance values X1 to X8 are optimized to give the largest communication capacity, the signal switching means 41 and 42 select a combination of the feeding antenna elements 11 to 14 having the highest communication capacity, thereby reducing the number of signal sources (transmission / reception). Even when only the device is used, a high communication capacity can be realized, and the wireless communication antenna device 1b can be simplified and reduced in power consumption.
Note that the switching by the signal switching means 41 and 42 may be performed by a user's operation according to the use situation, or may be automatically performed by the control unit according to the calculation result. .

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described.
FIG. 5 shows a fourth embodiment of the present invention.
In FIG. 5, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the third embodiment have the same basic configuration, and only the differences will be described here.

Diode elements 153, 154, 155, and 156 are attached to both ends of the power supply antenna elements 151 and 152 in the present embodiment, respectively. In addition, diode elements 163, 164, 165, and 166 are attached to both ends of the power supply antenna elements 161 and 162, respectively. The diode elements 153 to 156 can excite any one of the feeding antenna element 151 and the feeding antenna element 152.
For example, the diode elements 153 and 156 conduct a high-frequency signal by applying a forward bias voltage to the opposing diode elements 153 and 156 and applying a reverse bias voltage to the opposing diode elements 154 and 155. Thus, the vertically polarized feed antenna element 151 can be excited. On the other hand, since the diode elements 155 and 156 do not conduct high-frequency signals, the horizontally polarized feed antenna element 152 is not excited.

By manipulating the diode elements 153 to 156 in this way, the polarization characteristics of the feeding antenna elements 151 and 152 can be controlled. The polarization characteristics of the feed antenna elements 161 and 162 can be similarly controlled by operating the diode elements 163 to 166.
By selecting a polarized wave with the highest communication capacity by such means, a high communication capacity can be realized even when only a small signal source (transceiver) is used, and the radio communication antenna device 1c is simplified. Power consumption can be reduced.

(Embodiment 5)
Next, a fifth embodiment of the present invention will be described.
FIG. 6 shows a fifth embodiment of the present invention.
In FIG. 6, the same components as those shown in FIGS. 1 to 5 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and only the differences will be described here.

  The antenna device for wireless communication 1d according to the present embodiment includes transmitters and receivers 51 and 52 that transmit and receive signals, and a bias device (setting unit) that generates a bias voltage for changing reactance values X1 to X4 of reactance elements 31 to 34. ) 71 and signal processing means (setting means) 61 for performing various signal processing. The reactance elements 31 to 34 are variable reactance elements.

  With this configuration, when signals are received by the transceivers 51 and 52, the signals are input to the signal processing means 61. The signal processing means 61 determines reactance values X1 to X4. For example, the signal processing unit 61 sequentially changes the reactance values X1 to X4 from a low value to a high value, and selects the reactance values X1 to X4 that provide the highest SNR characteristics. Further, the signal processing means 61 may select a combination of reactance values X1 to X4 that provides the highest channel capacity. Further, the signal processing means 61 calculates a delay spread or the like from the received signal, determines whether it is an indoor environment or an outdoor environment from this delay spread, and is given in advance at the time of manufacture or the like and stored in the memory. Alternatively, reactance values X1 to X4 suitable for each environment may be read and set.

Then, the signal processing unit 61 inputs the determined reactance value information to the bias device 71. The bias device 71 inputs a bias signal corresponding to each reactance value information to the reactance elements 31 to 34. As a result, the reactance values X1 to X4 of the reactance elements 31 to 34 are set to values determined by the signal processing means 61.
It is also possible to perform recursive processing such as designing the signal processing means 61 to detect a more suitable bias condition based on the received signals from the transceivers 51 and 52.
By such means, when the propagation environment around the wireless communication antenna device 1d changes dynamically, for example, even when the terminal is on a moving vehicle, a high channel capacity is continuously realized. Is possible.

(Embodiment 6)
Next, a sixth embodiment of the present invention will be described.
FIG. 7 shows a sixth embodiment of the present invention.
In FIG. 7, the same components as those shown in FIGS. 1 to 6 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and only the differences will be described here.

The terminal station device (wireless communication antenna device) 81 in this embodiment is used as a terminal device of the wireless communication system 2 in which communication is performed wirelessly.
The terminal station device 81 includes feeding antenna elements 111 and 112 and parasitic antenna elements 211 and 212 with reactance elements provided between the feeding antenna elements 111 and 112. The configuration of the terminal station device (wireless communication antenna device) 82 is the same.
The base station apparatus (transmitting apparatus) 83 includes a plurality of transmitting antenna elements 83a and performs spatial multiplexing of a plurality of terminal stations in order to simultaneously communicate with the terminal station apparatuses 81 and 82 at the same frequency. In the terminal station device 81, appropriate reactance values X1 and X2 of the reactive elements of the parasitic antenna elements 211 and 212 with reactance elements are set. In the terminal station device 82, the reactive elements of the parasitic antenna elements 223 and 224 with reactive elements are set. The appropriate reactance values X3 and X4 are set. That is, the reactance values X1 to X4 are set to values that maximize the average value of the communication capacities of all the terminal station devices 81 and 82.
Thereby, the transmission capacity at the time of spatial multiplexing can be improved.
The reactance values X1 to X4 may be specified from the base station device 83. By doing so, the transmission capacity at the time of spatial multiplexing of the plurality of terminal station devices 81 and 82 can be improved, or the frequency utilization efficiency can be improved.

(Embodiment 7)
Next, a seventh embodiment of the present invention will be described.
FIG. 8 shows a seventh embodiment of the present invention.
In FIG. 8, the same components as those shown in FIGS. 1 to 7 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and only the differences will be described here.

  The wireless communication antenna device 1e in the present embodiment includes a decoupling circuit 45 connected to the feeding antenna elements 11 and 12. The decoupling circuit 45 is for improving the loss due to the coupling between elements generated between the feeding antenna elements 11 and 12. The decoupling circuit 45 is connected to two power supply means 7a and 8a, and these two power supply means 7a and 8a are connected to the ground G, respectively.

Here, for example, when a signal is transmitted from one power feeding means, the signal may be transmitted from one power feeding antenna element and input to the other power feeding means via the other power feeding antenna element. Conceivable.
However, the decoupling circuit 45 in this embodiment is designed so that a signal having the same amplitude and opposite phase as the signal transmitted from the power feeding antenna element 11 is input to the power feeding means 8a at the same time.
Therefore, it becomes possible to cancel the coupling between the power supply means 7a and the power supply means 8a.
This makes it possible to improve the SNR of the signal during transmission / reception.

(Embodiment 8)
Next, an eighth embodiment of the present invention will be described.
FIG. 9 is a flowchart showing the processing in the eighth embodiment of the present invention.
In FIG. 9, the same components as those shown in FIGS. 1 to 7 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and only the differences will be described here. The configuration of the present embodiment is the same as the configuration of the fifth embodiment (shown in FIG. 6).

In the present embodiment, a signal including base station antenna information (electrical characteristic information) such as a combination of polarizations of the base station antenna, the number of elements, and an element interval is transmitted from the base station antenna apparatus. Receives the signal (step S1).
Then, the radio communication antenna apparatus extracts base station antenna information from the received signal (step S2).
Next, the radio communication antenna apparatus determines the reactance value of each reactance element that can be expected to have the highest communication capacity from the extracted base station antenna information, and sets it (step S3). Specifically, for example, the reactance value is determined in the same manner as in the fifth embodiment.
Then, the wireless communication antenna device starts data transmission based on the set reactance value (step S4) and ends the process.
Even when the type of antenna of the base station is renewed by such means, or when the antenna device for wireless communication moves and starts communication with a base station antenna device having another antenna, the communication capacity is always high. Can be realized stably.

According to the present invention, the following effects can be obtained by the means described above.
For example, the installation location of the antenna element on the terminal is limited in an environment where the bottom of the chassis is placed horizontally, such as a small notebook personal computer, and is placed randomly in the horizontal direction. Even if it is difficult to achieve a high directivity gain, according to the present invention, the average gain in the horizontal plane can be improved. Then, by increasing the average gain, the SN ratio (signal to noise ratio) can be improved and the communication capacity can be improved.
Further, by appropriately giving the reactance value, the antenna coupling between the plurality of feeding antenna elements can be reduced, thereby further improving the S / N ratio.
In addition, since the spatial correlation between the feeding antenna elements can be reduced by appropriately giving the reactance value, it is possible to contribute to the improvement of the communication capacity.
Furthermore, since the parasitic antenna elements are shared between the two Yagi / Uda arrays, it is possible to achieve a high communication capacity by realizing a high S / N ratio and low spatial correlation even in a small antenna shape. .

In addition, by using two orthogonally polarized antennas, the number of antenna ports is doubled, so that a communication capacity of about twice can be realized with a slight increase in antenna size.
Also, when two orthogonally polarized antennas are used, the signal switching means can select the combination of polarized waves with the highest communication capacity, and high communication even when only a small number of signal sources (transceivers) are used. The capacity can be realized, and the antenna device for wireless communication can be simplified and the power consumption can be reduced.
Also, by making the polarization of the feed element variable, the polarization with the highest communication capacity can be selected, and even when only a small signal source (transceiver) is used, a high communication capacity can be realized. A wireless communication apparatus can be simplified and reduced in power consumption.

In addition, by providing a means for dynamically setting a reactance value, even when the environment fluctuates or when the antenna device for wireless communication is arranged in various environments, a high communication capacity is always stably achieved. Will be able to.
Even when a plurality of radio communication antenna devices are spatially multiplexed, by setting the reactance value so as to give a low spatial correlation between the plurality of radio communication antenna devices, a high communication capacity improvement effect due to spatial multiplexing can be obtained. Can be realized.

Further, by inserting a decoupling circuit between a plurality of feeding antenna elements, it is possible to improve the SNR characteristics and increase the communication capacity.
Also, when the antenna type of the transmitting station is renewed by transmitting the electrical characteristics of the antenna of the transmitting station from the transmitting station to the antenna device for wireless communication according to the present invention, or the antenna device for wireless communication is Even when moving and starting communication with a transmitting station apparatus having another antenna, a high communication capacity can always be stably realized.

In the first to eighth embodiments, the dielectric substrate 9 is provided. However, the configuration is not limited to this, and the configuration can be changed as appropriate. For example, instead of the dielectric substrate 9, the antenna elements may be connected and fixed with a connecting jig.
The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

It is a block diagram which shows typically the antenna apparatus for radio | wireless communication in the 1st Embodiment of this invention. It is a block diagram which shows typically the antenna apparatus for radio | wireless communication in the 2nd Embodiment of this invention. It is a figure which shows the numerical analysis result in this embodiment, Comprising: (a) is explanatory drawing which shows the indoor environment which performed numerical analysis, (b) is the result of having calculated | required the expected value of the channel capacity with respect to the reactance value of a reactance element. It is a graph to show. It is a block diagram which shows typically the antenna apparatus for radio | wireless communication in the 3rd Embodiment of this invention. It is a block diagram which shows typically the antenna apparatus for radio | wireless communication in the 4th Embodiment of this invention. It is a block diagram which shows typically the antenna apparatus for radio | wireless communication in the 5th Embodiment of this invention. It is a block diagram which shows typically the antenna apparatus for radio | wireless communication in the 6th Embodiment of this invention. It is a block diagram which shows typically the antenna apparatus for radio | wireless communication in the 7th Embodiment of this invention. It is a flowchart which shows the process in the antenna apparatus for radio | wireless communication in the 8th Embodiment of this invention. It is a perspective view which shows the 1st example of the conventional antenna apparatus for radio | wireless communication. It is a block diagram which shows typically the 2nd example of the conventional antenna apparatus for radio | wireless communication.

Explanation of symbols

1, 1a, 1b, 1c, 1d, 1e Radio communication antenna devices 11, 12, 13, 14 Feed antenna elements 21, 22, 23, 24, 25, 26, 27, 28 Parasitic antenna elements 31, 32, 33 , 34, 35, 36, 37, 38 Reactance elements 7, 7a, 8, 8a Power supply means 41, 42 Signal switching means 45 Decoupling circuit 61 Signal processing means (setting means)
71 Bias device (setting means)
81, 82 Terminal station device (antenna device for wireless communication)
83 Base station device (transmitting device)
83a Transmission antenna element 111, 112 Feed antenna element 121, 122 Feed antenna element 211, 212, 213, 214 Parasitic antenna element with reactance element 151, 152 Feed antenna element 161, 162 Feed antenna element

Claims (11)

A wireless communication antenna device in which a plurality of antenna elements having the same polarization characteristics are arranged in a row,
Among the antenna elements arranged in a row, the antenna elements at both ends of the row are feed antenna elements, and the remaining antenna elements arranged between the feed antenna elements at both ends are parasitic antenna elements. And
The parasitic antenna element is terminated by a reactance element,
The reactance values of the reactance elements are all set equal in the column, and are set to values that maximize the expected value of communication capacity in wireless communication. An antenna device in which antenna elements having both two orthogonal polarization characteristics are arranged in rows,
Among the antenna elements arranged in a row, the antenna elements at both ends of the row are feed antenna elements having independent feeding means corresponding to two orthogonally polarized waves, respectively. The remaining antenna elements arranged between the feeding antenna elements are parasitic antenna elements terminated by independent reactance elements corresponding to two orthogonal polarizations, respectively.
The reactance values of the reactance elements are all set equal in the columns corresponding to the respective polarizations, and are set to values that maximize the expected value of communication capacity in wireless communication. Antenna device. The antenna device for wireless communication according to claim 2,
A radio communication antenna apparatus comprising switching means for selectively feeding power to one of two orthogonal ports of the feeding antenna element. Parasitic antenna elements having both orthogonal polarization characteristics are arranged in rows,
An antenna apparatus comprising a feeding antenna element whose polarization direction is variable at both ends of the row,
The parasitic antenna element is terminated by an independent reactance element corresponding to each of two orthogonal polarizations,
The reactance values of the reactance elements are all set equal in the columns corresponding to the respective polarizations, and are set to values that maximize the expected value of communication capacity in wireless communication. Antenna device.   The wireless communication antenna device according to any one of claims 1 to 4,
  The reactance value of the reactance element is set so that the electric length of the parasitic antenna element is shorter than that of the feed antenna element, with the longitudinal direction in the row of the plurality of antenna elements being the horizontal direction and the thickness direction being the vertical direction. ,
  An antenna device for wireless communication characterized by the above.   The wireless communication antenna device according to any one of claims 1 to 5,
  The reactance values of the plurality of antenna elements are sequentially changed from a low value to a high value to select a reactance value that provides the highest SNR characteristics, or reactances of the plurality of antenna elements that provide the highest channel capacity. A second signal processing unit for selecting a combination of values;
  An antenna device for wireless communication, comprising:   The wireless communication antenna device according to any one of claims 1 to 6,
  The reactance value of the reactance element is
  Based on the electrical characteristic information included in the signal received from the base station antenna device, the signal including electrical characteristic information that is information on a combination of polarizations of base station antennas, the number of elements, or element spacing Is set to a value that maximizes the expected value of the communication capacity in wireless communication.
  An antenna device for wireless communication characterized by the above. The wireless communication antenna device according to any one of claims 1 to 7 ,
The reactance value of the reactance element is variable,
An antenna device for wireless communication, comprising setting means for setting a reactance value at which a maximum communication capacity is obtained at an arbitrary place or time. A wireless communication antenna device according to any one of claims 1 to 8 , wherein the antenna device is used as a terminal device in a wireless communication system.
A reactance value in which the average value of the communication capacities of all the radio communication antenna devices is set to be maximum when performing spatial multiplexing using a plurality of radio communication antenna devices at the same frequency at the same time. Communication antenna device. The wireless communication antenna device according to any one of claims 1 to 9 ,
The antenna apparatus for wireless communication, wherein the feeding antenna element is fed through a decoupling circuit that improves a loss due to coupling between elements generated between the feeding antenna elements. A wireless communication antenna apparatus in which a plurality of antenna elements having the same polarization characteristics are arranged in a row, and among the antenna elements arranged in a row, antenna elements at both ends of the row Is a feeding antenna element, the remaining antenna elements arranged between the feeding antenna elements at both ends are parasitic antenna elements, and the parasitic antenna element is terminated by a reactance element, and the reactance element The reactance value is a wireless communication method in the antenna device for wireless communication set to a value that maximizes the expected value of the communication capacity in wireless communication,
A signal including electrical characteristic information that is information on a combination of polarization of the transmission antenna elements , the number of elements, or an element interval, transmitted from a transmission apparatus including a plurality of transmission antenna elements,
Extracting the electrical characteristic information from the received signal,
A wireless communication method characterized in that all the reactance values of the reactance elements are set to be equal in the column using the extracted electrical characteristic information.

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