JP6539895B2 - Antenna device and wireless communication device - Google Patents

Description

  The present invention relates to an antenna device and a wireless communication device for wireless communication.

  Conventionally, for example, in mobile phones and the like, antenna structures have been proposed to support different frequency bands in order to perform communication for multiband (for example, 800 MHz band, 1.5 GHz band, 2 GHz band)). ing.

  For example, Patent Document 1 discloses an antenna apparatus including a dielectric substrate, a feeding unit, a monopole antenna, a parallel circuit, an antenna element, and a parasitic element as a multi-frequency shared type antenna apparatus. In this antenna device, the monopole antenna operates alone at the frequency f1 to suppress the leakage current to the dielectric substrate. The monopole antenna, the parallel circuit and the antenna element have a length of about 1⁄4 the wavelength of the frequency f2, resonate at the frequency f2, and operate as an antenna device at the frequency f2. Since the monopole antenna used at the frequency f1 is also used at the frequency f2, the antenna apparatus can be miniaturized.

  On the other hand, lower frequencies such as, for example, the 200 MHz band are used as a frequency band for multimedia broadcasting. Since the half wavelength in the 200 MHz band is 70 cm or more, it is required that the antenna on the mobile side at the time of performing mobile communication in such a frequency band be of a size that is easy to carry and carry.

  In order to meet such a demand, Patent Document 2 discloses a folding antenna device which is compact when carried and which can receive radio waves of a plurality of frequency bands when actually used as an antenna. This antenna device is provided with a first housing to which the first antenna is attached, a second housing to which the second antenna is attached, and a hinge portion that allows these two housings to be folded. The first and / or second antenna takes two states, a state of being housed in the housing and a state of being stretched from the housing, and receives the first frequency band in the state of being housed and is stretched In this state, radio waves in the second frequency band can be received.

  Furthermore, in recent years, with the tightness of frequency, effective use of a spatially and temporally available frequency band is mentioned as one of means for improving frequency utilization efficiency.

  Furthermore, Non-Patent Document 1 discloses a wideband discrete OFDM (Orthogonal Frequency Division Multiplexing) communication system as one of the methods of effective use of a frequency band.

  In general, a frequency band of 1 GHz or less is suitable for wireless communication from the viewpoint of propagation characteristics. As a frequency band used by the mobile communication system, frequencies of 700 MHz band and 900 MHz band are added by frequency reorganization accompanying the stop of analog terrestrial television broadcasting and the like.

  However, it is very difficult to newly secure a vacant frequency band of a large size capable of accommodating high-speed wireless transmission in a frequency band of 1 GHz or less.

  On the other hand, when looking at the actual frequency utilization condition of 1 GHz or less, although narrow bands, vacant frequency bands are discretely present between the bands of the existing communication systems. Although the use situation changes temporally and geographically, if these many small free frequency bands are flexibly bundled and used, it is possible to secure bandwidth capable of realizing high-speed wireless transmission.

  For that purpose, unlike the existing communication system, it is necessary to develop a communication technology that can flexibly cope with division of the transmission band and transmission in a plurality of frequency bands. OFDM (Orthogonal Frequency Division Multiplexing) communication scheme is a scheme in which information is multiplexed and transmitted on a plurality of relatively narrow band carriers (subcarriers) orthogonal to each other. By performing digital signal processing using Fourier Transform (Fast Fourier Transform) / FFT (Fast Fourier Transform), it has a feature that it is relatively easy to divide a transmission band. Discrete OFDM (Non-Contiguous OFDM) in which subcarriers are arranged in the vacant frequency band discretely present as described above, and these subcarriers are bundled to form a transmission path to realize high-speed transmission using this OFDM method. ) Technology is being considered.

  FIG. 11 is a diagram showing the basic concept of such discrete OFDM.

  With discrete OFDM, communication can be performed without interference by arranging subcarriers so as not to interfere with signals of other existing communication systems.

  FIG. 12 is a diagram showing an example of a conventional antenna that can be used in a wide band of 1 GHz or less.

  As a conventional antenna used in a frequency band of 1 GHz or less, there are, for example, a biconical antenna as shown in FIG. 12 (a) and a log-periodic antenna as shown in FIG. 12 (b). With such an antenna, for example, signals of 150 MHz to 1000 MHz can be targeted for transmission and reception. However, here too, the maximum dimension is difficult to miniaturize to 440 to 650 mm.

Japanese Patent Application Laid-Open No. 2006-67234 Unexamined-Japanese-Patent No. 2014-3549 specification

Koji Takakasaki, Toshio Hasegawa, Tatsuo Shibata, "Studies on Wideband Discrete OFDM Technology," Technical Report, vol. 113, no. 57, SR 2013-16, pp. 83-89, May 2013

  That is, although the aspect in which it is necessary to perform reception or transmission of a frequency of about 200 to 300 MHz in a terminal apparatus which is a mobile station has become apparent, it is not easy to miniaturize the antenna as described above .

  Also, in recent years, tablet computers have come to be widely used as portable communication terminals. Here, at the frequency of the 200 MHz band as described above, the half wavelength exceeds twice the length of the long side of the normal tablet computer. On the other hand, tablet computers are required to have as thin a housing as possible because of their ease of use, and it is difficult to provide a folding structure and a rod antenna as disclosed in Patent Document 2 in terms of device design. .

  That is, the demand for small wireless communication devices such as mobile phones continues to increase, and there are wireless systems using various frequencies, and there is also a demand for using them simultaneously. The small size wireless communication device has a small volume, and the area in which the antenna space can be installed is limited. Furthermore, if the size of the small radio itself is too small for the wavelength of the frequency to be used, the antenna operation changes depending on the frequency, and the antenna gain in the direction of communication changes significantly due to the different radiation patterns depending on the frequency. There was a problem that

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an antenna device which can be relatively miniaturized as compared with the wavelength of the target frequency. .

  Another object of the present invention is to provide an antenna device capable of miniaturizing a wireless communication device.

According to one aspect of the present invention, there is provided an antenna device for a wireless communication device having a housing, wherein a ground electrode is disposed, and a circuit board having a substantially rectangular shape is crossed with a long side and a short side of the circuit board. And a first antenna element provided along the long side direction and the short side direction of the circuit board and fed by the feed portion, the first antenna element comprising: When the second antenna element, respectively resonate at different frequency bands from each other, a first antenna element and second antenna element operates as a dipole antenna at the corresponding frequency bands by each excited with circuit board The width of the second antenna element is smaller than that of the first antenna element .

  Preferably, the first antenna element extends along the long side of the circuit board at least a predetermined distance from the circuit board, and the second antenna element at least a predetermined distance from the circuit board And extend along the short side direction of the circuit board.

  Preferably, the first and second antenna elements are metal layers formed on the outer surface of the housing.

According to another aspect of the present invention, there is provided a wireless communication device including: a circuit board on which a housing and a ground electrode are disposed, which has a substantially rectangular shape and on which a circuit for wireless communication is mounted; A feeding portion provided in the vicinity of an area where the side and the short side intersect, and first and second antenna elements disposed along the long side direction and the short side direction of the circuit board and fed by the feeding portion; The first antenna element and the second antenna element respectively resonate in frequency bands different from each other, and the first antenna element and the second antenna element each excite in the circuit board by exciting with the circuit board. Acting as a λ / 4 dipole antenna, the width of the second antenna element is smaller than that of the first antenna element .

  Preferably, the first antenna element extends along the long side of the circuit board at least a predetermined distance from the circuit board, and the second antenna element at least a predetermined distance from the circuit board And extend along the short side direction of the circuit board.

  Preferably, the first and second antenna elements are metal layers formed on the outer surface of the housing.

  According to the present invention, the antenna device can be relatively miniaturized as compared with the wavelength of the target frequency.

  Also, the wireless communication device can be relatively miniaturized as compared to the wavelength of the target frequency.

It is a conceptual diagram which shows the structure which provided the monopole antenna with respect to the circuit board 2. FIG. It is a figure for demonstrating the operation state in each frequency domain of the monopole antenna shown in FIG. FIG. 5 is a diagram showing current components when radiation is performed in the circuit board 2 and the monopole antenna 10; FIG. 2 is a diagram for describing a configuration of a monopole antenna of Embodiment 1; It is a figure for demonstrating the operation state in each frequency domain of the monopole antenna shown in FIG. FIG. 2 is a diagram showing an appearance of a wireless communication device 1000. FIG. 16 is a conceptual diagram showing a configuration in which a first antenna element 100-1 and a second antenna element 100-2 are provided in the wireless communication device 1000. 7 is a partially enlarged view of a region PB in the VII-VII ′ cross section of FIG. 7 (b). FIG. 5 is a diagram for explaining another configuration of the antenna device 100. FIG. It is a functional block diagram which shows the example of a structure of the radio | wireless communications system 2000 of this Embodiment. It is a figure which shows the basic concept of discrete OFDM. It is a figure which shows the example of the conventional antenna which can be used in a 1 GHz or less wide band.

  Hereinafter, a wireless communication apparatus using the antenna device according to the embodiment of the present invention will be described as an example. In the following embodiments, components and processing steps denoted by the same reference numerals are the same or equivalent, and the description thereof will not be repeated if not required.

  In order to miniaturize the antenna, it is conceivable to use a resonant wavelength of λ / 4 as a monopole antenna using an antenna element and a circuit board.

  However, even in this case, there are the following problems.

(Problems in monopole (dipole) antenna)
FIG. 1 is a conceptual view showing a structure in which a monopole antenna is provided to a circuit board 2.

  As shown in FIG. 1, for example, the circuit board 2 has a size of 160 mm × 240 mm, and an electronic circuit is mounted on the circuit board 2. For example, a ground electrode is provided on the back surface of the circuit board 2.

  As shown in FIG. 1, the length of the monopole antenna is, for example, about 200 mm, and the distance from the end of the substrate to the outer end of the monopole antenna is about 20 mm. It can be operated as an antenna that resonates λ / 4. At the upper left corner of the substrate 2, a feeding portion 20 to the antenna 10 is provided.

  As described below, at high frequencies, the circuit board 2 functions in the same manner as the ground, so this antenna equivalently operates as a dipole antenna in the resonant frequency region.

  FIG. 2 is a diagram for describing an operating state of each of the frequency ranges of the monopole antenna shown in FIG.

  Moreover, FIG. 3 is a figure which shows the current component at the time of radiation being performed in the circuit board 2 and the monopole antenna 10. As shown in FIG.

  FIG. 2 (a) is a diagram showing the main radiation components and radiation directivity in the case of 200 MHz.

  As shown in the upper part of FIG. 2 (a) and FIG. 3 (a), the current generated in the monopole antenna 10 cancels the current generated on the substrate 2 side, so the current of this portion is at the time of transmission. It hardly contributes to the radiation pattern of radio waves (or the induced electromotive force at the time of reception). The main radiation pattern of the antenna is generated by current components in the vicinity of the feeding point of the junction between the substrate 2 and the monopole antenna 10 and generally in the substrate 2 toward the feeding point and in the direction depending on the frequency.

  Therefore, the radiation pattern is close to the radiation pattern as a dipole antenna as shown in FIG. 3 (b).

  That is, as shown in the lower part of FIG. 2A, as a typical form of the directivity of the dipole antenna, the directivity in the horizontal plane of the antenna has the maximum intensity in the direction perpendicular to the antenna, and in the direction of the antenna Indicates directivity in which the intensity is almost zero (hereinafter referred to as “eight-shaped radiation pattern”).

  FIG. 2 (b) is a diagram showing the main radiation components and radiation directivity in the case of 300 MHz.

  As shown in the upper part of FIG. 2B, the current component has a similar distribution at 200 MHz.

  On the other hand, as shown in the lower part of FIG. 2B, the directivity of the antenna in the horizontal plane slightly distorts the “eight-shaped radiation pattern” and exhibits asymmetric directivity.

  FIG. 2 (c) is a diagram showing the main radiation components and the directivity of radiation in the case of 500 MHz.

  As shown in the upper part of FIG. 2 (c), the current component has a distribution similar to that at 200 MHz, but the antenna no longer resonates at λ / 4, and FIG. 3 (c) As shown in the lower part of the figure, the directivity in the horizontal plane of the antenna is far from the “eight-shaped radiation pattern” and it can not be said that the antenna operates as a dipole.

That is, it can be understood that it is difficult to realize a monopole antenna which performs a dipole operation equivalent to a substrate in a wide band and using an antenna and a substrate of a size as shown in FIG.
First Embodiment
FIG. 4 is a diagram for explaining the configuration of the monopole antenna according to the first embodiment.

  In addition, the dimension in a figure is an example and is a thing at the time of assuming the frequency band of 200-500 MHz as object. The dimensions are not necessarily limited to those illustrated.

  In FIG. 4, antenna elements 100-1 operating as a monopole antenna of λ / 4 resonance around 200 to 300 MHz and 100-2 operating as a monopole antenna of λ / 4 resonance around 450 to 550 MHz with a thickness of 1 mm The configuration in the case of forming on a circuit board 300 having an area of 160 × 240 mm is shown as a conceptual diagram.

  In the following, when the antenna element 100-1 and the antenna element 100-2 are generically referred to, they are referred to as the antenna device 100.

  The circuit board 300 is provided in the housing of the wireless communication device, and basically, as shown in FIG. 4, the shape of the upper surface is described as being rectangular. However, as long as it has a substantially rectangular shape, a part may be missing from the rectangle or a part may be protruding. In such a substantially rectangular shape, the direction along the long side is referred to as the "long side direction", and the direction along the short side is referred to as the "short side direction". Thus, for example, “P extends along the long side direction” means that P has a shape along the same direction as the long side direction, regardless of whether P is present on the substrate or not. It shall mean what you are doing.

  The antenna element 100-1 corresponding to the low frequency band of the target frequency band of the antenna device 100 is separated from the circuit board 300 by a predetermined distance (for example, 20 mm) or more, and the first long side of the circuit board 300 It extends along the direction.

  In the vicinity of one end of the first long side of the circuit board 300 and in the vicinity of the corner surrounded by the antenna element 100-1 and the antenna element 100-2, as described below, the feeding portion to the antenna device 100 It is assumed that 20 is provided.

  The antenna element 100-2 corresponding to the band on the high frequency side of the target frequency band of the antenna device 100 extends from the feeding unit 20 along the short side direction of the circuit board 300. Further, in response to the antenna element 100-2 corresponding to the high frequency side, the width (width) of the antenna is smaller (smaller) in the antenna element 100-2 than in the antenna element 100-1. Is set as.

  Since the length and width of the antenna element actually depend on the material, shape, and the like of the substrate 2, for example, by using an existing simulator, it is appropriately changed to a desired resonance frequency band. While being designed.

  As described above, the resonant frequency area of the antenna element 100-1 and the resonant frequency area of the antenna element 100-2 are set to be separated, and in the target frequency band of the antenna device 100, the antenna element 100-1 and the antenna element Each of 100-2 operates as a λ / 4 long antenna element in the corresponding resonant frequency region.

  Here, on the circuit board 300, a transmission / reception circuit for performing transmission processing (encoding processing, modulation processing and the like) and reception processing (demodulation processing, decoding processing and the like) in wireless communication is provided. Here, at least one of the antenna elements 100-1 and 100-2 may be provided on the circuit board 300. The formation of an antenna on a substrate is also disclosed, for example, in the above-mentioned Patent Document 1. Alternatively, as described later, the antenna element 100-1 and the antenna element 100-2 may be provided on the outer surface side of the housing of the wireless communication device.

  The substrate is not particularly limited, and for example, a low temperature co-fired ceramic substrate, a glass epoxy substrate, a composite substrate or the like can be used, and the circuit of the wireless communication device is formed on the substrate as described above.

  In FIG. 4, although the hatched area is actually an area where an electronic circuit including an RF circuit is formed, the area functions as a ground when viewed from the antenna element.

  FIG. 5 is a diagram for explaining an operating state of each of the frequency ranges of the monopole antenna shown in FIG.

  FIG. 5 (a) is a diagram showing the main radiation components and radiation directivity in the case of 200 MHz.

  As shown in the upper part of FIG. 5A, the current generated in the monopole antennas 100-1 and 100-2 cancels the current generated on the substrate 2 side. It hardly contributes to the radiation pattern (or the induced electromotive force at the time of reception). The main radiation pattern of the antenna is generated by current components in the vicinity of the feeding portion 20 of the junction between the substrate 2 and the monopole antenna 10 and roughly in the substrate 2 toward the feeding point and in the direction depending on the frequency.

  Therefore, as shown in the lower part of FIG. 5A, as a typical form of the directivity of the dipole antenna, the directivity in the horizontal plane of the antenna has maximum strength in the direction perpendicular to the antenna, and in the direction of the antenna Is an "eight-shaped radiation pattern" whose intensity is almost zero.

  FIG. 5 (b) is a diagram showing the main radiation components and radiation directivity in the case of 300 MHz.

  As shown in the upper part of FIG. 5B, the current component has a similar distribution at 200 MHz.

  On the other hand, as shown in the lower part of FIG. 5B, the directivity in the horizontal plane of the antenna also maintains a radiation pattern similar to the “eight-shaped radiation pattern”.

  FIG. 5C is a diagram showing the main radiation components and the directivity of radiation in the case of 500 MHz.

  As shown in the upper part of FIG. 5C, the current component has a distribution similar to that at 200 MHz, and as shown in the lower part of FIG. 5C, although the asymmetry is increased, the antenna The directivity of the antenna in the horizontal plane maintains the “figure-like radiation pattern” to some extent, and it can be said that the antenna operates as a dipole.

That is, by combining the antenna elements 100-1 and 100-2, it is possible to realize a monopole antenna that performs dipole operation in a wide band.
Second Embodiment
Hereinafter, an example of a specific configuration in which the antenna device 100 described in the first embodiment is mounted on the wireless communication device 1000 will be described as the second embodiment.

  FIG. 6 is a diagram showing the appearance of the wireless communication apparatus 1000. As shown in FIG.

  The wireless communication device 1000 is, for example, a tablet terminal, and is provided with a housing 1010 and a touch-type liquid crystal panel 1020 as a display device and an input device.

  FIG. 7 is a conceptual diagram showing a configuration in which the first antenna element 100-1 and the second antenna element 100-2 are provided in the wireless communication device 1000.

  7B shows a state in which the circuit board 300 etc. are viewed through the housing 1010, and FIG. 7A is a partially enlarged view of a region surrounded by an ellipse PA in FIG. 7B. It is.

  As shown to Fig.7 (a), the electric power feeding part 20 is provided on the circuit board 300, and the electric power feeding part 20, the 1st antenna element 100-1, and the 2nd antenna element 100-2 are connected.

  Further, as shown in FIG. 7B, a first antenna is provided on the outer surface of the housing 1010 over a part of the first long side of the rectangular housing 1010 and a short side on the side where the feeding point 20 exists. An element 100-1 is provided. Further, the second antenna element 100-2 is provided on the outer surface of the housing 1010 over part of the short side of the rectangular housing 1010 on the side where the feeding point 20 is present.

  Here, assuming that the dimensions of the circuit board 300 are, for example, 130 mm × 200 mm × 1 mm, if the external dimension of the upper surface of the case is 150 mm × 200 mm, the circuit board 300 and the first long side The clearance with can be taken 20 mm.

  FIG. 8 is a partially enlarged view of the region PB in the VII-VII ′ cross section of FIG. 7B.

  Referring to FIG. 8, the liquid crystal panel 1020 includes a surface glass 1020-1, a liquid crystal display unit and a touch sensor 1020-2, and a liquid crystal holding unit and a control unit 1020-3.

  In addition, the circuit board 300 is supported by the housing 1010 by being fitted into a recess formed in a resin that forms the housing 1010. The mounting component 312 is mounted on both sides of the circuit board 300.

  An antenna element 100-2 is provided on the outer surface of the housing 1010. The method of forming such an antenna element is not particularly limited. For example, the antenna element can be configured by depositing or printing a metal pattern on the outside of the housing. Such a configuration can be similarly applied to the antenna element 100-1.

  By thus configuring the antenna element, the distance between the circuit board 300 and the metal pattern of the antenna element can be secured without affecting the housing size. For example, in the example shown in FIG. 8, it is possible to secure 10 mm or more of the size of the clearance as described in the present embodiment.

  Note that the antenna element may further be covered with a member for shielding so that the antenna elements 100-1 and 100-2 do not directly touch the operator's hand or the like.

  FIG. 9 is a diagram for explaining another configuration of the antenna device 100. As shown in FIG.

  7 and 8, the antenna device 100 has been described as being provided on the outer surface of the housing of the wireless transmission device 1000.

  However, the antenna elements 100-1 and 100-2 may have a rod-like shape such as a foldable whip antenna for the wireless transmission device 1000.

In this case, as shown in FIG. 9, each antenna element can be operated as a dipole antenna by expanding the antenna elements 100-1 and 100-2 in a direction substantially balanced with the current distribution in the substrate 2. It becomes.
[Example of transceiver configuration]
Hereinafter, the case where the antenna apparatus 100 of the embodiment as described above is used for the wireless communication apparatus of the discrete OFDM scheme described above will be described as an example.

  However, the antenna device 100 is applicable not only to the discrete OFDM wireless communication device but also to a small wireless communication device that transmits and receives wide band frequencies.

  FIG. 10 is a functional block diagram showing an example of a configuration of a wireless communication system 2000 according to the present embodiment.

  Although the configuration below is not particularly limited, each function related to transmission will be described as being based on the LTE standard.

  Referring to FIG. 1, in wireless communication system 2000, since the frequency band to be transmitted and received is extremely wide, for example, for downlink, both the transmitting side and the receiving side correspond to the respective frequencies. Arrange the unit. In FIG. 10, a configuration in which four systems are arranged is shown as an example.

  Also, the downlink (downlink) band from the base station to the user terminal and the uplink (uplink) band from the user terminal to the base station are independently secured in a completely separated frequency band (FDD: frequency It is possible to adopt a division multiplexing) configuration or (TDD: time division multiplexing) configuration used at different times. However, assuming that communication is performed using an extremely wide frequency bandwidth, the TDD configuration may be used from the viewpoint of securing the bandwidth.

  On the other hand, since the target frequency is different depending on each high frequency unit, the quality of the communication path such as the propagation attenuation and the Doppler frequency is largely different.

  Therefore, first, on the transmission side of the wireless communication system 2000, two systems of channel encoders 110-1 and 110-2 are provided in order to improve frequency utilization efficiency by transmission according to the quality of the communication path. The channel encoders 110-1 and 110-2 respectively perform processing such as channel error correction coding such as Turbo coding and interleaving. The channel encoder carries out processing such as adaptive modulation according to the communication quality of the target free frequency band.

  In the following, it will be described that which frequency band is used as a free frequency band for communication is known on the transmitting side and the receiving side.

  After the processing of channel encoders 110-1 and 110-2, modulators 112-1 and 112-2 perform predetermined digital modulation processing on the transmission signal. As digital modulation, for example, QPSK, 16 QAM, 64 QAM, etc. can be used.

  In the wireless communication system 2000, IFFT / FFT processing is used to realize discrete placement of subcarriers. By assigning the number of IFFT / FFT points (for example, 8192) to one high frequency unit covering a predetermined band, each IFFT / FFT point corresponds to a subcarrier of a predetermined bandwidth (for example, 15 kHz) . In other words, each high frequency unit has a transmission capability of subcarriers for the number of IFFT / FFT points.

  In the subcarrier mapper 120, the transmitting side (for example, the base station apparatus) arranges modulation data at an IFFT point corresponding to a subcarrier to be transmitted among subcarriers of the high frequency unit. The arrangement of such subcarriers may be changed in response to fluctuations in the available frequency band depending on the place and time at which communication is performed. Such arrangement information is assumed to have common information in advance on the transmitting side and the receiving side.

  Thereafter, IFFT units 130-1 to 130-4 execute IFFT processing for each high frequency unit, and D / A converters 132-1 to 132-4 convert the signals into analog signals.

  The outputs of D / A converters 132-1 to 132-4 are mixed with IF signals from IF oscillator 133 and mixers 134-1 to 134-4, and local oscillators 140-1 to 140-1 corresponding to respective frequency bands are further mixed. It mixes with the output of 140-4, and mixer 136-1-136-4.

  In the radio communication system 2000, a target radio frequency (RF) is, for example, 170 MHz to 1 GHz, and an intermediate frequency (IF) to be set lower than the RF frequency is usually secured in the device configuration of the radio transceiver. Have difficulty. Therefore, in FIG. 1, an IF frequency higher than RF is used. Note that a direct conversion method without using an IF may be adopted.

  The functional block 142 is a functional block that performs a function as an FDD duplexer when implementing FDD, and performs a function as a TDD switch when implementing TDD.

  The signal from block 142 is emitted from antenna 150.

  On the other hand, on the reception side, the signal received by the antenna 200 is subjected to the function as an FDD duplexer or TDD switch by the functional block 202, and then the outputs of the local oscillators 204-1 to 204-4 corresponding to each frequency band And mixers 210-1 to 210-4.

  When the receiving side is, for example, a tablet terminal, the antenna device 100 can be used as the antenna 200.

  Further, the outputs of the mixers 210-1 to 210-4 are mixed with the IF signal from the IF oscillator 211 and the mixers 212-1 to 212-4, and the A / D converters 214-1 to 214-4 perform A / D. After being converted, FFT processing which is inverse processing of IFFT processing is executed in FFT sections 220-1 to 220-4.

  The subcarrier demapper 230 extracts the data of the corresponding FFT point by the reverse processing of the subcarrier mapper 120 for the signal separated for each subcarrier from the FFT units 220-1 to 220-4, and performs a demodulator 240-1 to 240-2 execute demodulation processing. Furthermore, the channel decoders 250-1 to 250-2 execute deinterleaving processing and error correction processing.

  The configuration on the uplink side is basically the same as the configuration on the downlink side, but in FIG. 10, the illustration is simplified.

  The feedback channel modulation encoder 280 modulates a control signal that feeds back the reception status of the reception side (for example, mobile station apparatus) to the base station side to perform control such as adaptive modulation, and the feedback channel demodulation decoder 180 Demodulate such feedback control signals.

  With the above-described configuration, the antenna device can be relatively miniaturized as compared to the wavelength of the target frequency.

  Also, the wireless communication device can be relatively miniaturized as compared to the wavelength of the target frequency.

  The embodiment disclosed this time is an illustration of a configuration for specifically implementing the present invention, and does not limit the technical scope of the present invention. The technical scope of the present invention is indicated not by the description of the embodiment but by the scope of claims, and includes modifications within the scope of wording and meaning of the scope of claims. Is intended.

  Reference Signs List 20 power supply unit, 100 antenna device, 100-1 first antenna element, 100-2 second antenna element, 300 circuit board, 1000 wireless communication device, 1010 housing, 1020 liquid crystal panel.

Claims (6)

An antenna device for a wireless communication device having a housing, the antenna device comprising:
A circuit board having a substantially rectangular shape on which a ground electrode is disposed;
A feeding portion provided in the vicinity of an area where the long side and the short side of the circuit board intersect;
And first and second antenna elements disposed along the long side direction and the short side direction of the circuit board and fed by the feeding unit,
The first antenna element and the second antenna element respectively resonate in different frequency bands, and the first antenna element and the second antenna element are excited by the circuit board. Operate as a dipole antenna in the corresponding frequency band ,
An antenna device, wherein a width of the second antenna element is smaller than that of the first antenna element . The first antenna element extends along the long side direction of the circuit board at a predetermined distance from the circuit board at least.
The antenna device according to claim 1, wherein the second antenna element extends along a short side direction of the circuit board at a predetermined distance from the circuit board. Wherein the first and second antenna elements, said a housing metal layer formed on the outer surface of, claim 2 Symbol placement of the antenna device. A wireless communication device,
And
A circuit board on which a ground electrode is disposed, which has a substantially rectangular shape, and on which a circuit for wireless communication is mounted;
A feeding portion provided in the vicinity of an area where the long side and the short side of the circuit board intersect;
First and second antenna elements disposed along the long side direction and the short side direction of the circuit board and fed by the feeding unit;
The first antenna element and the second antenna element respectively resonate in different frequency bands, and the first antenna element and the second antenna element are excited by the circuit board. Operate as a λ / 4 dipole antenna in the corresponding frequency band ,
The wireless communication device , wherein the width of the second antenna element is smaller than that of the first antenna element . The first antenna element extends along the long side direction of the circuit board at a predetermined distance from the circuit board at least.
The wireless communication device according to claim 4, wherein the second antenna element extends along the short side direction of the circuit board at a predetermined distance from the circuit board. Wherein the first and second antenna elements, the casing is a metal layer formed on the outer surface of claim 5 Symbol mounting of the wireless communication device.