JP2009182947A - Antenna control device, receiving device, and antenna control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antenna control device, a receiving device, and an antenna control method, capable of attaining a reduced size and a simplified structure. <P>SOLUTION: The receiving device 1 comprises: a variable directivity antenna 6; an antenna control signal supply part 14 which supplies an antenna control signal for controlling the directivity of the antenna 6 in a superposition state over DC voltage; an antenna control signal acquisition part 10 which acquires the antenna control signal from a signal supplied from the supply part 14; a DC voltage generation part 9 which generates a DC voltage having a predetermined voltage value from the signal supplied from the supply part 14; and an antenna directivity control part 7 which controls the directivity of the antenna 6 based on the antenna control signal acquired by the acquisition part 10. The control part 7 controls the directivity of the antenna 6 by use of the DC voltage outputted from the generation part 9. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an antenna control device and an antenna control method provided in a communication device that performs wireless communication. The present invention also relates to a receiving apparatus using this antenna control apparatus.

  In recent years, with the development of digital compression coding technology and high-speed communication technology, digitization in satellite and terrestrial broadcast communication and digitization in mobile communication such as mobile phones has been realized. With the realization of digitalization in broadcast signals and mobile communication, this digital communication technology is used in various fields such as in-vehicle digital broadcast reception, portable mobile communication, and wireless LAN.

  In a communication apparatus using such a communication technology, for example, a receiving apparatus, an antenna is provided for good reception. In particular, a variable directivity antenna that can receive signals satisfactorily by changing the directivity in the reception direction may be used. When using a variable directional antenna, the electric field strength of the received radio wave is so low that it cannot be satisfactorily received using a normal omnidirectional antenna that has substantially the same reception conditions for all reception directions. Even in this case, it is possible to receive well. Further, when used for mobile communication, the antenna directivity can be changed in accordance with the changing reception conditions, so that optimum reception can be performed.

When a variable directivity antenna is used, an antenna control device is required to control the directivity of the variable directivity antenna. As an antenna control device, for example, there is an antenna control device proposed in Patent Document 1. FIG. 22 is a block diagram illustrating a schematic configuration of a receiving device including the antenna control device proposed in Patent Document 1. In FIG. As illustrated in FIG. 22, the receiving apparatus 100 includes a plurality of antennas 101a to 101e, a demodulation unit 102 that demodulates signals received by the antennas 101a to 101e, and a connection between the plurality of antennas 101a to 101e and the demodulation unit 102. And a switching unit 103 that transmits a signal received from a desired antenna to the demodulation unit. Further, the switching unit 103 is received by the connection switch 104 that switches the connection between the plurality of antennas 101a to 101e and the demodulation unit 102, the connection switch control unit 105 that controls the connection of the connection switch 104, and the antennas 101a to 101e. And an inductor 106 that prevents a signal from being input to the connection switch control unit 105. The connection switch control unit 105 controls connection of the connection switch 104 based on a signal output from the demodulation unit 102 to the switching unit 103 and passes through the inductor 106 and input to the connection switch control unit 105. With this configuration, a signal received by a desired antenna among the antennas 101a to 101e can be input to the demodulation unit 102.
JP-A-5-14901

  However, such a configuration using the switching unit 103 that switches connection between each of the plurality of antennas 101a to 101e and the demodulating unit 102 leads to an increase in the size of the receiving device 100. Moreover, since it becomes necessary to arrange a signal line from each of the antennas 101a to 101e to the switching unit 103, the configuration of the receiving apparatus 100 becomes complicated.

  In view of such a problem, an object of the present invention is to provide an antenna control device, a reception device, and an antenna control method that are miniaturized and simplified.

  In order to achieve the above object, an antenna control apparatus according to the present invention includes an antenna unit that includes a variable directivity antenna that wirelessly communicates a signal and that has a variable directivity in a communication direction, and a signal that is input to and output from the antenna unit. In the antenna control device provided in the communication device including the signal conversion unit for converting the signal, the antenna control signal provided in the signal conversion unit and superimposing the antenna control signal for controlling the directivity of the variable directivity antenna is superimposed on the DC voltage. An antenna control signal supply unit that supplies the antenna unit; an antenna directivity control unit that is provided in the antenna unit and outputs a signal for controlling the directivity of the variable directional antenna to the variable directional antenna; The antenna control unit includes an antenna control included in the signal supplied from the antenna control signal supply unit. Based on the signal, characterized in that it comprises an antenna control signal acquiring unit for controlling the antenna directivity control unit.

  Further, in the antenna control device having the above configuration, the antenna directivity control unit outputs a DC voltage obtained by converting a signal supplied from the antenna control signal supply unit to the variable directivity antenna. The directivity of the variable directivity antenna may be controlled.

  With this configuration, the DC component of the signal input to the antenna unit can be used as a signal for controlling the variable directivity antenna. Therefore, it is not necessary to separately provide a power source for outputting a signal for controlling the variable directivity antenna in the antenna portion, and the configuration of the antenna control device can be reduced in size and simplified.

  Further, in the antenna control device having the above configuration, the variable directivity antenna is provided between the parasitic element having at least two ends grounded, and a signal to be communicated with the signal conversion unit. A signal that is provided in each of the parasitic elements and a variable reactance element in which reactance with respect to a signal to be communicated is variable, and the reactance of the variable reactance element is output from the antenna directivity control unit It may be determined by the voltage value.

  In the antenna control device having the above-described configuration, the variable reactance element is a varactor diode, and the anode of one of the varactor diodes is provided on one end side of the parasitic element that is grounded, and the other varactor diode is provided. Are provided so as to be on one end side of the parasitic element that is grounded, and a capacitor is provided between the varactor diode and one end of the parasitic element that is grounded, and the antenna directivity control unit A DC voltage may be applied to both ends of the varactor diode of each of the parasitic elements by a signal supplied from.

  In the antenna control device having the above configuration, a signal output from the antenna directivity control unit may be input to the parasitic element via the power supply / reception element. With such a configuration, the wiring for applying a signal to each parasitic element can be reduced, so that the configuration of the antenna control device can be simplified.

  In the antenna control device having the above configuration, the antenna control signal may be a direct current signal and a signal that can take at least two states having different voltage values.

  With this configuration, the antenna control signal acquisition unit need only have a configuration for detecting only the magnitude of the DC voltage supplied from the antenna control signal supply unit. Therefore, a complicated demodulator or the like is not necessary. Therefore, it is possible to reduce the size and simplification of the configuration of the antenna control device.

  In the antenna control device having the above-described configuration, the antenna control signal may be a signal that can take a state where the voltage value fluctuates in a pulse shape and a direct current state where the voltage value becomes a predetermined voltage value.

  With this configuration, the voltage value of the signal supplied to the antenna unit is usually constant at a certain value, and temporarily varies in a pulse shape only when the directivity is switched. Therefore, the DC voltage supplied by the antenna control signal supply unit becomes substantially constant, and it becomes easy to convert and use the DC voltage in the antenna unit. Furthermore, since the voltage value of the direct current DC voltage can be made as small as possible, power saving can be achieved.

  In the antenna control device having the above-described configuration, the antenna control signal may be a signal that can take an AC state having a predetermined frequency and a DC state having a predetermined voltage value.

  With this configuration, it is only necessary to determine whether or not an AC voltage is superimposed on the signal supplied to the antenna unit. Therefore, a simple element such as a capacitor or a diode is used to transmit the antenna control signal. Detection and determination are possible. Therefore, the size and simplification of the configuration of the antenna control device can be achieved.

  In the antenna control device having the above-described configuration, the antenna control signal may be an AC signal and a signal that can take at least two states having different frequencies.

  With this configuration, it is possible to obtain a DC voltage having a constant and stable magnitude simply by removing the high-frequency component of the signal supplied to the antenna unit. In addition, since only the frequency is increased or decreased, the signal fluctuation is small, and the generation of noise can be suppressed.

  In the antenna control device having the above configuration, the antenna control signal may be an AC signal having a predetermined frequency and a signal that can take at least two states having different phases.

  With this configuration, the frequency of the AC voltage superimposed on the DC voltage of the signal supplied to the antenna unit is constant. Therefore, the optimization of the device that removes the high-frequency component from this signal is facilitated, and the configuration of the antenna control device can be simplified. In addition, the DC voltage obtained by removing the high frequency component is constant and stable.

  Further, the receiving device of the present invention is a receiving device including an antenna unit including an antenna that receives a signal and whose directivity in a receiving direction is variable, and a demodulating unit that demodulates a signal input to the antenna unit. An antenna control signal supply unit that is provided in the demodulator unit and that superimposes an antenna control signal for controlling the directivity of the variable directivity antenna on a DC voltage and supplies the antenna unit to the antenna unit; and An antenna directivity control unit for outputting a signal for controlling the directivity of the variable directivity antenna to the variable directivity antenna; and a signal provided from the antenna control signal supply unit and superimposed on a signal supplied from the antenna control signal supply unit An antenna control signal acquisition unit for controlling the antenna directivity control unit based on the antenna control signal It is characterized in.

  Further, in the receiving apparatus having the above-described configuration, an amplifier that amplifies the received signal, a DC voltage generation unit that converts a signal supplied from the antenna control signal supply unit to generate a DC voltage and supplies the DC voltage to the amplifier, The antenna directivity control unit controls the directivity of the variable directivity antenna by outputting to the variable directivity antenna a DC voltage based on the DC voltage output from the DC voltage generation unit. It doesn't matter.

  With this configuration, the directivity of the variable directivity antenna can be controlled using a DC voltage for amplifying the received signal. Therefore, a device such as a power source for controlling the directivity of the variable directivity antenna is not required. Therefore, it is possible to reduce the size and simplification of the configuration of the receiving apparatus.

  The antenna control method of the present invention includes an antenna unit including an antenna that wirelessly communicates a signal and has a variable directivity in a communication direction, and a signal conversion unit that converts a signal input to and output from the antenna unit. In the antenna control method for a communication device, an antenna control signal for controlling the directivity of the variable directivity antenna is superimposed on a DC voltage and supplied to the antenna unit, and the antenna unit includes an antenna included in the supplied signal. The variable directional antenna is controlled based on a control signal.

  According to the present invention, the directivity of the variable directivity antenna can be controlled only by changing the DC voltage supplied to the antenna unit. Therefore, it is not necessary to separately provide a switching device for switching the connection between the antenna and the signal conversion unit, so that the communication device can be reduced in size and simplified.

<< Basic configuration >>
<Configuration of receiving device>
First, the configuration of a receiving apparatus to which an antenna control apparatus and an antenna control method according to the present invention are applied will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a receiving apparatus according to an embodiment of the present invention.

  In addition, the receiving apparatus 1 shown below is an ISDB-T (Integrated Services Digital Broadcasting for Terrestrial) terrestrial wave in which a signal digitally modulated by an Orthogonal Frequency Division Multiplex (OFDM) system is transmitted as an example. The case where the present invention is applied to a digital television broadcast receiving apparatus will be described as an example. However, it may be a receiver that receives a broadcast of another communication system, or a receiver that receives a signal other than a television broadcast. You may apply to an apparatus.

  1 includes an antenna unit 2 that receives a signal, a demodulation unit 3 that demodulates a signal received by the antenna unit 2, a signal line 4 that connects the antenna unit 2 and the demodulation unit 3, A video / audio processing unit 5 that performs processing for converting a signal output from the demodulation unit 3 into an output signal that can be displayed and reproduced by an output device (not shown) such as a display device or a speaker.

  The antenna unit 2 receives a high frequency (Radio Frequency, hereinafter referred to as RF) signal and can control the directivity in the reception direction, and the direct current supplied to the variable directivity antenna 6. An antenna directivity control unit 7 that controls the directivity of the variable directivity antenna 6 by controlling the voltage, and a low noise amplifier (hereinafter referred to as LNA) that amplifies the RF signal output from the variable directivity antenna 6. 8), a DC voltage generator 9 that converts a DC voltage input from the demodulator 3 via the signal line 4 and supplies the converted voltage to the LNA 8 and the antenna directivity controller 7, and an input via the signal line 4. And an antenna control signal acquisition unit 10 that controls the antenna directivity control unit 7 based on the antenna control signal to be transmitted.

  The antenna unit 2 further includes a capacitor C1 having one end connected to the LNA 8 and the other end connected to the signal line 4, and one end connected to the signal line 4 and the other end connected to the DC voltage generating unit 9 and the antenna. And an inductor L1 connected to the control signal acquisition unit 10.

  The demodulator 3 selects and acquires a signal having a desired frequency from the input signals, and performs frequency conversion and amplification, a demodulator 12 that demodulates the signal output from the tuner 11, and a negative electrode Is connected to the antenna unit 2 via the signal line 4 and the DC power source 13 connected to the positive electrode of the DC power source 13 and controls the DC voltage output from the DC power source 13 to control the antenna. An antenna control signal supply unit 14 that generates a signal and an antenna control unit 15 that controls the antenna control signal supply unit 14 based on signals output from the tuner unit 11 and the demodulator 12 are provided.

  The demodulator 3 further includes a capacitor C2 having one end connected to the tuner unit 11 and the other end connected to the signal line 4, and one end connected to the signal line 4 and the other end connected to the antenna control signal supply unit. 14, and an inductor L <b> 2 connected to 14.

  The capacitors C <b> 1 and C <b> 2 are provided in order to prevent the DC voltage applied to the signal line 4 from being input to the LNA 8 and the tuner unit 11. The inductors L1 and L2 are provided to suppress the RF signal from being input from the signal line 4 to the DC voltage generation unit 9, the antenna control signal acquisition unit 10, and the antenna control signal supply unit 14.

  Note that although a configuration in which the direct current voltage output from the direct current voltage generation unit 9 is input to the antenna directivity control unit 7 is shown, the direct current voltage input to the signal line 4 is directly applied to the antenna directivity control unit 7. It may be configured to be input to The antenna control unit 15 may control the antenna control signal supply unit 14 based on a signal output from either the tuner unit 11 or the demodulator 12.

<Receive operation>
Next, the receiving operation of the receiving apparatus 1 having the above-described configuration will be described with reference to FIG. When the reception operation is started, first, an RF signal is received by the variable directivity antenna 6. The received RF signal is amplified by the LNA 8 and input to the tuner unit 11 of the demodulation unit 3 via the signal line 4. The tuner unit 11 selects and amplifies a signal having a desired frequency from the input RF signal, and performs frequency conversion to a signal having an intermediate frequency (hereinafter referred to as IF). The tuner unit 11 also amplifies the IF signal after frequency conversion.

  The IF signal output from the tuner unit 11 is input to the demodulator 12 and demodulated. The demodulation process is in accordance with the modulation method of the signal input from the antenna. As the modulation method, for example, QAM (Quadrature Amplitude Modulation), QPSK (Quadrature Phase Shift Keying), DQPSK (Differential Quadrature Phase Shift Keying). and so on. The demodulator 12 performs an equalization process for correcting the distortion of the signal generated during transmission. As a method of this equalization processing, for example, there is a method of correcting a signal by obtaining a transmission path characteristic from a reference signal having a known intensity included in the signal. This correction is performed in both the frequency axis and the time axis. Note that the signal may be subjected to fast Fourier transform and converted to a signal on the frequency axis before this equalization processing is performed.

  The signal demodulated by the demodulator 12 is input to the video / audio processing unit 5 and converted into an output signal that can be displayed and reproduced by an output device such as a display device or a speaker. This output signal may include not only video and audio signals but also other data signals.

<Configuration of variable directional antenna>
Next, an example of the above-described variable directivity antenna 6 will be described with reference to FIGS. 2 to 4 are block diagrams showing examples of the configuration of the variable directivity antenna.

  The variable directivity antenna 6a shown in FIG. 2 is set as a reception antenna by selecting one of the two directivity antennas 61 and 62 having different directivity in the reception direction and the two directivity antennas 61 and 62. An antenna selector 63. The antenna selection unit 63 selects the directional antennas 61 and 62 based on the antenna control voltage output from the antenna directivity control unit 7.

  In the variable directivity antenna 6a shown in FIG. 2, since the directivity antennas 61 and 62 and the antenna selection unit 63 are integrated, it is possible to reduce the size compared to a configuration in which a plurality of antennas are connected and switched. In addition, since the directivity of the directional antennas 61 and 62 is different, it is easier and more efficient than the configuration in which an antenna capable of performing good reception is selected from a plurality of omnidirectional antennas. Can be received.

  Next, the case where an ESPAR (Electronically Steerable Passive Array Radiator) antenna is used as the variable directivity antenna will be described with reference to FIGS. 3 and 4.

  The variable directivity antenna 6b shown in FIG. 3 includes a power supply / reception element 64 that receives an electromagnetic wave signal and inputs it to the LNA 8, and parasitic elements 65 and 66 that are provided around the element and control directivity. Also, a resistor R1 whose one end is connected to the parasitic element 65, R2 whose one end is connected to the parasitic element 66, and one end side provided to the parasitic element 65 and connected to the parasitic element 65 of the resistor R1 is the cathode side. The varactor diode VD1 is provided in the parasitic element 66, and one end connected to the parasitic element 66 of the resistor R2 is the anode side. One end is connected to the anode of the varactor diode VD1, and the other end is grounded. And a capacitor C4 having one end connected to the cathode of the varactor diode VD2 and the other end grounded.

One DC potential V _ant1 output by the antenna directivity control unit 7 is connected to a connection node between the anode of the varactor diode VD1 and one end of the capacitor C3 and a connection node between the cathode of the varactor diode VD2 and one end of the capacitor C4. Is applied. The other DC potential V _ant2 output from the antenna directivity control unit 7 is applied to the other end of the resistor R1 and the other end of the resistor R2.

  As described above, the antenna directivity control unit 7 applies the antenna control voltage, which is a DC voltage, to the variable directivity antenna 6b. In particular, a DC voltage is applied to each of the varactor diodes VD1 and VD2. The directivity of the variable directivity antenna 6b of this example can be controlled by controlling the DC voltage applied to the varactor diodes VD1 and VD2.

In the case of V _ant1 > V _ant2 , that is, the anode side of the varactor diode VD1 and the cathode side of the varactor diode VD2 are made larger than the potentials of the cathode side of the varactor diode VD1 and the anode side of the varactor diode VD2, A case where a DC voltage is applied to VD1 and VD2 will be described. In this case, a forward bias voltage is applied to the varactor diode VD1, and a reverse bias voltage is applied to the varactor diode VD2. It is assumed that the DC voltage applied at this time is larger than the forward voltage drop of the varactor diodes VD1 and VD2.

In this case, since the capacity of the varactor diode VD1 to which the forward bias voltage is applied increases (reactance decreases), the RF signal easily passes through the varactor diode VD1, and is in a pseudo grounded state. Accordingly, the parasitic element 65 operates as a reflective element. On the other hand, since the capacity of the varactor diode VD2 to which the reverse bias voltage is applied is reduced (reactance is increased), it is difficult for the RF signal to pass through the varactor diode VD2. Therefore, the parasitic element 66 operates as a waveguide element. As described above, the directivity on the parasitic element 66 side can be increased by applying a forward bias voltage to the varactor diode VD1 and a reverse bias voltage to the varactor diode VD2 as V _ant1 > V _ant2 .

Contrary to the above case, when V _ant1 <V _ant2 , that is, the potentials on the anode side of the varactor diode VD1 and the cathode side of the varactor diode VD2 are set on the cathode side of the varactor diode VD1 and the anode side of the varactor diode VD2. A case where the potential is made smaller than the potential will be described. In this case, a reverse bias voltage is applied to the varactor diode VD1, and a forward bias voltage is applied to the varactor diode VD2.

At this time, contrary to the above case, the capacity of the varactor diode VD1 decreases (reactance increases), and the capacity of the varactor diode VD2 increases (reactance decreases). Therefore, the parasitic element 65 in which the RF signal is difficult to pass operates as a waveguide element, and the parasitic element 66 in which the RF signal is easily grounded operates as a reflection element. As described above, the directivity on the parasitic element 65 side can be increased by applying a reverse bias voltage to the varactor diode VD1 and a forward bias voltage to the varactor diode VD2 as V _ant1 <V _ant2 .

  The capacitors C3 and C4 are provided to prevent the applied DC voltage from being grounded. The RF signal that has passed through the varactor diodes VD1 and VD2 is grounded via these capacitors C3 and C4.

  Further, the variable directivity antenna 6c shown in FIG. 4 includes a power supply / reception element 64, parasitic elements 65 and 66, varactor diodes VD1 and VD2, and capacitors C3 and C4 similar to the variable directivity antenna 6b shown in FIG. . One end is connected to the cathode side of the varactor diode VD1 in the parasitic element 65 and the other end is connected to the power supply / reception element 64, and one end is connected to the anode side of the varactor diode VD2 in the parasitic element 66. A resistor R4 whose other end is connected to the power supply / reception element 64 and a capacitor C5 whose one end is connected to the power supply / reception element 64 and whose other end is connected to the LNA 8.

One DC potential V _ant1 supplied from the antenna directivity control unit 7 is connected to the connection node between the anode of the varactor diode VD1 and one end of the capacitor C3 and the varactor diode VD2 in the same manner as the variable directivity antenna 6b shown in FIG. To the connection node between the cathode and the one end of the capacitor C4. The other DC potential _Vant2 is input to the power _supply / reception element and applied to the other _ends of the resistors R3 and R4. Accordingly, a DC voltage is applied to varactor diodes VD1 and VD2, respectively, similarly to variable directivity antenna 6b shown in FIG.

The change in directivity due to the applied DC voltage is the same as that of the variable directivity antenna 6b shown in FIG. That is, the directivity of the parasitic element 66 increases when V _ant1 > V _ant2 , and the directivity of the parasitic element 65 increases when V _ant1 <V _ant2 . Further, the capacitor C5 suppresses the DC voltage applied to the power supply / reception element 64 from being input to the LNA 8.

  By using the variable directivity antennas 6b and 6c as shown in FIG. 3 and FIG. 4, the number of antennas can be reduced to one, so that the size of the receiving apparatus 1 can be reduced. Furthermore, since the directivity of the variable directivity antennas 6b and 6c can be switched using a DC voltage for driving the LNA 8, it is not necessary to separately provide a power source or the like in order to output a signal for switching directivity. Therefore, the receiving device 1 can be reduced in size and simplified.

  4 can be applied to the varactor diodes VD1 and VD2 by superimposing a DC voltage on the RF signal flowing through the power supply / reception element 64, the wiring is reduced. Simplification can be achieved.

  In the variable directivity antennas 6a to 6c shown in FIGS. 2 to 4, there are two directivity states that can be realized, but two or more directivity states may be used. When the number of states that can be realized is two or more, the number of directional antennas of the variable directivity antenna 6a shown in FIG. 2 is two or more, and the number of antennas that can be selected by the antenna selection unit 63 is two or more. I do not care.

Similarly, when the variable directivity antennas 6b and 6c shown in FIGS. 3 and 4 can be realized in two or more states, the parasitic elements 65 and 66, the varactor diodes VD1 and VD2, and the resistors R1 and R2 or R3 and R4. The same configuration as the capacitors C3 and C4 may be increased. For example, in FIG. 3, the same configuration as the parasitic elements 65 and 66 (including varactor diodes VD1 and VD2, resistors R1 and R2, and capacitors C3 and C4) may be added. At this time, the power supply / reception element 64 is disposed at a position surrounded by the parasitic elements 65 and 66 and the increased parasitic elements. Furthermore, assuming that the DC potential similar to V _ant1, V _ANT2 is supplied from the antenna directivity control unit 7 with respect to a parasitic element increases, it may be be controlled separately from the parasitic element 65 and 66. If comprised in this way, the direction which can control directivity will be two directions. Therefore, there are four states that can be realized.

  In the following, a case where the variable directivity antenna 6 of FIG. 1 is the variable directivity antenna 6c shown in FIG. 4 will be described as an example. However, a variable directivity antenna of another configuration is used. It doesn't matter.

<Variable directional antenna control operation>
Next, a specific control operation of the above-described variable directivity antenna 6 will be described with reference to FIG. First, the antenna control unit 15 that controls the variable directivity antenna 6 controls the directivity of the variable directivity antenna 6 based on signals output from the tuner unit 11 and the demodulator 12. More specifically, the antenna control unit 15 changes the directivity of the variable directivity antenna 6 when it detects the deterioration of the reception state based on the signal output from the tuner unit 11 or the demodulator 12. Control.

  As signals output from the tuner unit 11 and the demodulator 12, for example, signals indicating the average power of signals such as RF signals and IF signals processed in the tuner unit 11 and the demodulator 12, RF signals in the tuner unit 11 or A signal that determines the amplification factor of the IF signal (Automatic Gain Control signal, hereinafter referred to as AGC signal), a signal that indicates a CN ratio that is a ratio of the carrier wave to noise, and a signal that indicates the code error rate during demodulation and so on.

  In the case of detecting the deterioration of the reception status using the signal indicating the average power or the AGC signal, the reception status is determined when the signal indicating the average power or the AGC signal exceeds a predetermined value and becomes too small or too large. Can be determined to have deteriorated. In particular, control is performed to change the directivity when the intensity of the received signal is too small.

  When the CN ratio is used, when the CN ratio becomes smaller than a predetermined value, it can be determined that the reception condition is deteriorated due to large noise. Further, in the case of using the code error rate, when the code error rate becomes larger than a predetermined value, it can be determined that an accurate reception operation is not performed and the reception state is deteriorated. Note that the above signals are merely examples, and degradation of the reception status may be detected using other signals. Further, it is possible to detect the deterioration of the reception status based on a plurality of signals.

  When the antenna control unit 15 detects the deterioration of the reception status, the antenna control signal supplied to the antenna unit 2 via the signal line 4 is changed in order to change the directivity of the variable directivity antenna 6. At this time, the antenna control signal is sent to the antenna unit 2 by controlling the antenna control signal supply unit 14 to change the DC voltage applied to the signal line 4. Details of the configuration and operation of the antenna control signal supply unit 14 will be described later.

  In the antenna unit 2, the DC voltage generation unit 9 converts a DC voltage including an antenna control signal input via the signal line 4 and supplies a DC voltage to be supplied to the antenna directivity control unit 7 and the LNA 8. Generate. The antenna control signal acquisition unit 10 acquires the antenna control signal from the signal including the antenna control signal input via the signal line 4 and controls the antenna directivity control unit 7 based on the antenna control signal. To do.

By controlling in this way, it is possible to change the directivity of the variable directivity antenna 6 simply by changing the DC voltage applied to the antenna unit 2 and to improve the deterioration of the reception situation. Become. More specifically, for example, the directivity V _ant1 and V _ant2 supplied to the variable directivity antenna 6c shown in FIG. 4 is controlled by the antenna directivity control unit 7, thereby changing the directivity of the variable directivity antenna 6c. be able to. The details of the configuration of the antenna directivity control unit 7, the DC voltage generation unit 9, and the antenna control signal acquisition unit 10 will be described later.

  Note that the detection of deterioration of the reception status by the antenna control unit 15 may be performed at predetermined time intervals. Further, the reception status may be compared before and after the change of the directivity of the variable directivity antenna 6. Furthermore, when the reception situation after the change in directivity is deteriorated from before the change, the directivity of the variable directivity antenna 6 may be changed again to change to another state or to return to the state before the change. I do not care. In addition, when the receiving apparatus 1 is activated, the state of the best reception state is determined by comparing the reception state in each state that the variable directivity antenna 6 can realize, and the state is received as the initial state. The operation may be performed.

<< Example >>
<First embodiment>
Next, configuration examples of the antenna directivity control unit 7, the DC voltage generation unit 9, the antenna control signal acquisition unit 10, and the antenna control signal supply unit 14 that control the directivity of the variable directivity antenna 6 correspond to the configurations. An example of an antenna control signal to be performed will be described. Initially, the structure of the receiver in a 1st Example is demonstrated using FIGS. FIG. 5 is a block diagram showing the configuration of the antenna control signal supply unit of the receiving apparatus in the first embodiment, and FIG. 6 shows the output voltage output from the antenna control signal supply section of the receiving apparatus in the first embodiment. It is a graph to show. FIG. 7 is a block diagram illustrating configurations of an antenna directivity control unit, a DC voltage generation unit, and an antenna control signal acquisition unit of the receiving apparatus according to the first embodiment.

  As shown in FIG. 5, the antenna control signal supply unit 14 a provided in the receiving apparatus 1 of the present example is connected to the positive electrode of the DC power supply 13 and the magnitude of the DC voltage output by the resistance value of the connected resistor. The determined voltage variable regulator 16, the resistor R5 having one end connected to the voltage variable regulator 16, the resistor R6 having one end connected to the other end of the resistor R5 and the other end grounded, the resistor R5 and the resistor R6 And a switch SW1 for determining whether or not the connection node can be connected to the other end of the resistor R6.

  Whether or not the switch SW1 can be connected is controlled by the antenna control unit 15. When the switch SW1 is connected (ON), the switch SW1 bypasses the resistor R6, and the state voltage variable regulator 16 is connected to the resistor R5 whose other end is grounded. On the other hand, when the switch SW1 is not connected (OFF), the resistor R5 and the resistor R6 are connected in series to the voltage variable regulator 16, and the other end of the resistor R6 is grounded. That is, when the switch SW1 is turned on, the resistance value of the resistor connected to the voltage variable regulator 16 is small, and when the switch SW1 is turned off, the resistance value of the resistor connected to the voltage variable regulator 16 is large.

  For example, when the voltage variable regulator 16 has a larger output voltage value as the resistance value of the connected resistor is larger, the voltage value V2 output when the switch SW1 is ON is the same as that of the switch SW1. It becomes smaller than the voltage V1 output in the OFF state. In this case, as shown in the graph of the output voltage output from the antenna control signal supply unit 14a in FIG. 6, a DC voltage having a voltage value of either V1 or V2 is output.

Further, as shown in FIG. 7, the DC voltage generator 9 a includes a regulator 17 to which the DC voltage output from the demodulator 3 is input via the signal line 4. The regulator 17 converts the input DC voltage and outputs a DC voltage having a predetermined voltage value V _amp .

  The antenna control signal acquisition unit 10a includes a resistor R7 to which a DC voltage output from the regulator 17 is supplied at one end, a resistor R8 having one end connected to the other end of the resistor R7 and the other end grounded, and a signal at one end. A resistor R9 to which a DC voltage output from the demodulator 3 is supplied via the line 4, a resistor R10 having one end connected to the other end of the resistor R9 and the other end grounded, and an inverting input terminal (−) Are connected to the connection node of the resistors R7 and R8, the connection node of the resistors R9 and R10 is connected to the non-inverting input terminal (+), and the voltage value input to the inverting input terminal (−) and the non-inverting input A comparator CMP that compares the voltage value input to the terminal (+) and outputs an H or L signal.

The DC voltage of the voltage value V _amp output from the regulator 17 is divided by the resistors R7 and R8 to become a predetermined voltage value V _R and is input to the inverting input terminal (−) of the comparator CMP. Similarly, the non-inverting input terminal (+) is divided by the resistors R9 and R10 to become the voltage value V1a or V2a, and is input to the non-inverting input terminal (+).

Here, when the DC voltage having the voltage value V1 is output from the antenna control signal supply unit 14a, the DC voltage having the voltage value V1a is input to the non-inverting input terminal (+), and the voltage value V2 from the antenna control signal supply unit 14a. It is assumed that a DC voltage having a voltage value V2a is input to the non-inverting input terminal (+). Each voltage value satisfies the relationship of V1a> V _R > V2a. Therefore, when a DC voltage having a voltage value V1a is input to the non-inverting input terminal (+), an H signal is output from the comparator CMP, and a DC voltage having a voltage value V2a is input to the non-inverting input terminal (+). In this case, an L signal is output from the comparator CMP.

The antenna directivity control unit 7a includes a booster 18 which outputs a DC voltage by boosting a DC voltage supplied from the regulator 17 to the voltage value V _ant, two terminals S1, S2 and four contacts T1~ And a switch SW2 whose connection is controlled by a signal output from the comparator CMP. In the switch SW2, the terminal S1 and the contact T1 are connected, the terminal S2 and the contact T3 are connected, the terminal S1 and the contact T2 are connected, and the terminal S2 and the contact T4 are connected. The connection state is one of two connection states. For example, when the signal output from the comparator CMP is H, the terminal S1 and the contact T1, the terminal S2 and the contact T3 are respectively connected, and when the signal output from the comparator CMP is L, the terminal S1 and the contact T2, It is assumed that the terminal S2 and the contact T4 are connected to each other.

Further, the potential supplied to the variable directional antenna 6 via the terminal S1 of the switch SW2 is the above-described DC potential _Vant1, and the potential supplied to the variable directional antenna 6 via the terminal S2 is the above-described DC potential V. _ant2 .

In the configuration of the first embodiment described above, when the antenna control unit 15 performs control so that the switch SW1 is turned on, a DC voltage having the voltage value V1 is output from the voltage variable regulator 16. Then, an H signal is output from the comparator CMP, and the DC potential V _ant1 supplied to the variable directivity antenna 6 becomes substantially equal to V _ant . On the other hand, the DC potential V _ant2 becomes the ground potential. Therefore, V _ant1 > V _{ant2 and} the directivity of the parasitic element 66 shown in FIG. 4 is increased.

In addition, when the antenna control unit 15 performs control so that the switch SW <b> 1 is turned off, a DC voltage having a voltage value V <b> 2 is output from the voltage variable regulator 16. Then, an L signal is output from the comparator CMP, and the DC potential V _ant1 supplied to the variable directivity antenna 6 becomes the ground potential. On the other hand, the DC potential V _ant2 becomes substantially equal to V _ant . Therefore, V _ant1 <V _ant2 , and the directivity of the parasitic element 65 shown in FIG. 4 increases.

With the configuration of this example, the DC voltages V _ant1 and V _ant2 supplied to the variable directivity antenna 6 can be controlled only by changing the voltage values V 1 and V 2 of the DC voltage supplied to the antenna unit 2. It becomes possible. Further, the variable directivity antenna 6 can be controlled by the supplied DC voltages V _ant1 and V _ant2 . Therefore, it is not necessary to separately provide a switching device such as the switching unit 103 illustrated in FIG. 22, and thus the receiving device 1 can be reduced in size and simplified.

  Further, since the antenna control signal acquisition unit 10a only needs to detect the magnitude of the DC voltage supplied via the signal line 4, a complicated demodulator is not required. For this reason, the configuration of the receiving device 1 can be reduced in size and simplified.

Note that the resistors R5 and R6 and the switch SW1 connected to the variable voltage regulator 16 may be variable resistors whose resistance values are controlled by the antenna control unit 15. Further, to the magnitude relation between the voltage value V1, V2 of the DC voltage outputted from the variable voltage regulator 16 may be a reverse relationship, the non-inverting input terminal (+) to the DC voltage of the voltage value V _R of the comparator CMP And a DC voltage having a voltage value V1a or V2a may be input to the inverting input terminal (−).

  Any other configuration may be used as long as the antenna control unit 15 selects and outputs one of two DC voltages having different voltage values from the demodulation unit 3. In addition, as long as the antenna unit 2 is configured to detect a difference in the voltage value of the DC voltage input via the signal line 4 and control the directivity of the variable directivity antenna 6, other configurations are possible. It doesn't matter.

Further, the variable directivity antenna 6 may be configured to be able to take two or more states as described above, and the antenna control signal supply unit 14a may output a DC voltage having two or more voltage values. . In this case, for example, in the antenna control signal supply unit 14a, two or more resistors R5 and R6 that are connected in series may be provided and at least one switch SW1 that bypasses the resistance by being turned on may be provided. It may be configured to include a variable resistor whose resistance value can be set. In the antenna control signal acquisition unit 10a, one or more comparators CMP for determining a voltage value may be provided, and each comparator CMP may compare with a predetermined voltage value. Further, one or more switches SW2 whose connection is controlled based on signals output from the respective comparators CMP are provided, and the DC potentials V _ant1 and V _ant2 are applied to the variable directivity antenna 6 from the respective switches SW2. I do not care.

<Second embodiment>
Next, the configuration of the receiving apparatus according to the second embodiment will be described with reference to FIGS. FIG. 8 is a block diagram showing the configuration of the antenna control signal supply unit of the receiving apparatus in the first embodiment, and FIG. 9 shows the output voltage output from the antenna control signal supply section of the receiving apparatus in the second embodiment. It is a graph to show. FIG. 10 is a block diagram illustrating configurations of an antenna directivity control unit, a DC voltage generation unit, and an antenna control signal acquisition unit of the receiving apparatus according to the second embodiment.

  As shown in FIG. 8, the antenna control signal supply unit 14 b provided in the receiving device 1 of the present example is connected to the positive electrode of the DC power supply 13 and outputs the DC voltage input to the DC voltage output from the DC power supply 13. A superimposing unit 19 that outputs the superimposed data, a DC power supply 20 that supplies a DC voltage to the superimposing unit 19 and whose negative electrode is grounded, and a switch SW3 that determines whether or not the superimposing unit 19 and the positive electrode of the DC power supply 20 can be connected. And a pulse generator 21 for outputting a signal for controlling the connection of the switch SW3.

  Whether or not the switch SW3 can be connected is controlled by a pulse signal output from the pulse generator 21, and the operation of the pulse generator 21 is controlled by the antenna controller 15. The switch SW3 is temporarily not connected (OFF) by the input pulse signal, and is always connected (ON) unless a pulse signal is input.

  When the switch SW3 is ON, the DC voltage output from the DC power source 20 is superimposed on the DC voltage output from the DC power source 13 in the superimposing unit 19, and the DC voltage having the voltage value V3 is transmitted from the antenna control signal supplying unit 14b. Is output. When the switch SW3 is OFF, the DC voltage output from the DC power source 20 is output without being superimposed on the DC voltage output from the DC power source 13, so that the voltage value V4 is smaller than the voltage value V3. A DC voltage is output from the antenna control signal supply unit 14b. In this case, as shown in the graph of the output voltage output from the antenna control signal supply unit 14b in FIG. 9, the DC voltage of the voltage value V4 is pulsed while the DC voltage of the voltage value V3 is continuously output. An output period is formed.

  Further, as shown in FIG. 10, the DC voltage generator 9b includes a regulator 17 similar to that of the first embodiment. The antenna control signal acquisition unit 10b includes a pulse detection unit 22 that detects a pulsed voltage change input via the signal line 4, and an antenna directivity control unit based on a signal output from the pulse detection unit 22. A switch control signal generator 23 for outputting a switch control signal for controlling 7b.

  The antenna directivity control unit 7b includes a booster 18 similar to that in the first embodiment and a switch SW2. However, connection of the switch SW2 is controlled by a switch control signal output from the switch control signal generator 23.

  In the configuration of the second embodiment, for example, the directivity of the parasitic element 66 of the variable directivity antenna 6 shown in FIG. 4 is set to be large, and the antenna control unit 15 has the directivity of the parasitic element 65. A case of switching so as to increase will be described. At this time, the antenna controller 15 first controls the pulse generator 21 to output one pulse signal. When the pulse signal is output, the switch SW3 is temporarily turned OFF, and a pulse-like period having the voltage value V4 is formed in the DC voltage having the voltage value V3 output from the antenna control signal supply unit 14b. The pulse detection unit 22 detects that the voltage value of the DC voltage input via the signal line 4 has changed to V4 in a pulse form, and detects that a pulse-like change in the voltage value has been detected. Tell 23. The switch control signal generator 23 switches the connection of the switch SW2 by outputting a switch control signal to the switch SW2.

Before the switch SW2 connection is switched, the terminal S1 and the contact T1, and the terminal S2 and the contact T3 are connected to each other. However, the terminal S1 and the contact T2, and the terminal S2 and the contact T4 are connected by switching the connection. It becomes a state. As a result, the DC potential V _ant1 supplied to the variable directivity antenna 6 becomes the ground potential, and the DC potential V _ant2 becomes substantially equal to V _ant . Therefore, V _ant1 <V _ant2 , and the directivity of the parasitic element 65 shown in FIG. 4 increases.

The same applies to the case where the directivity of the parasitic element 66 is increased, and the antenna control unit 15 controls the pulse generation unit 21 to generate one pulse signal. Similarly, the pulse detector 22 detects a pulse-like change in the DC voltage input via the signal line 4, and the switch control signal generator 23 outputs a switch control signal. As a result, the connection of the switch SW2 is switched, and V _ant1 > V _{ant2 is satisfied} , and the directivity of the parasitic element 66 is increased.

By _adopting the configuration of this example, the DC potential V _ant1 supplied to the variable directivity antenna 6 is formed only by forming a pulse-like period of the voltage value V4 in the DC voltage that is the voltage value V3 supplied to the antenna unit 2. , V _ant2 can be controlled. _Further , the directivity of the variable directivity antenna 6 can be controlled by the supplied DC potentials V _ant1 and V _ant2 . Therefore, it is not necessary to separately provide a switching device such as the switching unit 103 illustrated in FIG. 22, and thus the receiving device 1 can be reduced in size and simplified.

Further, since the voltage value of the DC voltage supplied from the demodulator 3 to the antenna unit 2 is normally constant at V3 and temporarily falls to V4, the signal line 4 from the demodulator 4 is formed. The DC voltage input to the antenna unit 2 via is substantially constant. As a result, the operation of the regulator 17 can be stabilized and the configuration can be reduced in size and simplified. Furthermore, even if the magnitude of the voltage value V3 is as small as possible, the DC voltage that becomes the voltage value V _amp can be stably supplied from the regulator 17, so that power saving can be achieved.

  The switch SW3 may be turned on when a pulse signal is generated from the pulse generator 21. That is, a DC voltage with a voltage value of V4 is normally output, and a pulse-like period with a voltage value of V3 may be formed when the directivity of the variable directivity antenna 6 is switched. . The superimposing unit 19 may include a circuit such as an adding circuit.

  Further, the pulse detection unit 22 may be configured to detect that a pulse having the voltage value V4 is generated when the voltage value falls below a predetermined threshold (less than V3 and greater than V4). Further, the switch control signal may be a pulse signal, and the connection of the switch SW2 may be switched every time the switch control signal is input. The switch control signal may be a signal that is continuously output to the switch SW2, and the connection state of the switch SW2 may be determined according to the value of the output switch control signal.

  The antenna control unit 15 outputs a DC voltage having a predetermined voltage value from the demodulating unit 3 and can be controlled to change the voltage value in a pulse shape as necessary. It does not matter as a configuration. Further, in the antenna unit 2, any configuration that can detect that the voltage value of the DC voltage input via the signal line 4 has changed in a pulse shape and can control the directivity of the variable directivity antenna 6 is possible. Other configurations may be used.

  Further, assuming that the variable directivity antenna 6 can take two or more states as described above, the antenna directivity control unit 7b may include one or more switches SW2 whose connection is controlled by a switch control signal. Absent.

  In this case, for example, a pulse signal may be output from the pulse generation unit 21 until the antenna control unit 15 detects that the reception state is improved. Each time a pulse-like switch control signal is input from the switch control signal generator 23 to the antenna directivity control unit 7b, the directivity voltage applied to the variable directivity antenna 6 by the antenna directivity control unit 7b is changed. The directivity of the variable directivity antenna 6 may be changed in order.

  In addition, each state that the variable directivity antenna 6 can take may correspond to the number of pulse signals output from the pulse generation unit 21 per unit time. Then, the voltage value of the switch control signal output from the switch control signal generator 23 is determined according to the number of pulse-like changes in the DC voltage detected by the pulse detector 22 per unit time, and the variable directivity is determined. The directivity of the antenna 6 may be controlled.

<Third embodiment>
Next, the configuration of the receiving apparatus according to the third embodiment will be described with reference to FIGS. FIG. 11 is a block diagram showing the configuration of the antenna control signal supply unit of the receiving apparatus in the third embodiment. FIG. 12 shows the output voltage output from the antenna control signal supply section of the receiving apparatus in the third embodiment. It is a graph to show. FIG. 13 is a block diagram illustrating configurations of an antenna directivity control unit, a DC voltage generation unit, and an antenna control signal acquisition unit of the receiving apparatus according to the third embodiment.

  As shown in FIG. 11, the antenna control signal supply unit 14 c provided in the receiving apparatus 1 of the present example oscillates the superimposing unit 19 similar to that of the second embodiment and the DC voltage input to the superimposing unit 19. An oscillating unit 24 that superimposes an AC voltage on the voltage, and a switch SW4 that is controlled by the antenna control unit 15 and determines whether or not the superimposing unit 19 and the oscillating unit 24 can be connected to each other.

  Whether or not the switch SW4 can be connected is controlled by the antenna control unit 15. When the switch SW4 is connected (ON), an AC voltage is superimposed on the DC voltage output from the DC power supply 13 by the oscillating unit 24, and a signal in which the AC voltage is superimposed on the DC voltage is an antenna control signal supply unit. 14c. When the switch SW3 is not connected (OFF), the AC voltage is output without being superimposed on the DC voltage output from the DC power supply 13. In this case, as shown in the graph of the output voltage output from the antenna control signal supply unit 14c in FIG. 12, either the signal in which the AC voltage is superimposed on the DC voltage of the voltage value V4 or the DC voltage of the voltage value V4 is Is output.

  Further, as shown in FIG. 13, the DC voltage generation unit 9 c outputs an LPF (Low-Pass Filter) 25 to which a signal output from the antenna control signal supply unit 14 c is input via the signal line 4, and an output from the LPF 25. And a regulator 17 similar to those in the first and second embodiments.

  The antenna control signal acquisition unit 10c includes a capacitor C6 to which a signal output from the antenna control signal supply unit 14c via the signal line 4 is supplied at one end, and a diode D1 having an anode connected to the other end of the capacitor C6. And a capacitor C7 having one end connected to the cathode of the diode D1 and the other end grounded, and a switch control signal generator 23 similar to the second embodiment to which a connection node between the capacitor C7 and the diode D1 is connected. .

  Capacitor C6 suppresses a DC component in the input signal. Further, the diode D1 performs half-wave rectification on the AC component input through the capacitor C6. The capacitor C 7 smoothes the half-wave rectified AC component and outputs the smoothed AC component to the switch control signal generator 23. Therefore, if an AC component is included in the signal output from the antenna control signal supply unit 14 c, a DC voltage having a predetermined voltage value is applied to the switch control signal generation unit 23.

  The antenna directivity control unit 7c includes a booster 18 similar to those in the first and second embodiments, and a switch SW2. However, the connection of the switch SW2 is controlled by the switch control signal output from the switch control signal generator 23, as in the second embodiment.

In the configuration of the third embodiment described above, when the antenna control unit 15 performs control so that the switch SW4 is turned on, the superimposition unit 19 outputs a signal in which an AC voltage is superimposed on the DC voltage of the voltage value V4. Then, the AC component is extracted by the antenna control signal acquisition unit 10 c, rectified and smoothed, and a DC voltage having a predetermined voltage value is input to the switch control signal generation unit 23. At this time, for example, if a switch control signal indicating that the terminal S1 and the contact T1, and the terminal S2 and the contact T3 are connected is output from the switch control signal generation unit 23 to the switch SW2, The supplied DC potential V _ant1 is substantially equal to V _ant . On the other hand, the DC potential V _ant2 becomes the ground potential. Therefore, V _ant1 > V _{ant2 and} the directivity of the parasitic element 66 shown in FIG. 4 is increased.

Further, when the antenna control unit 15 performs control so that the switch SW4 is turned off, a DC voltage having a voltage value V4 is output from the superimposing unit 19. Then, the DC voltage is cut off by the capacitor C6, and a DC voltage having a predetermined value is not input to the switch control signal generator 23. At this time, for example, if a switch control signal for connecting the terminal S1 and the contact T2, and the terminal S2 and the contact T4 is output from the switch control signal generating unit 23 to the switch SW2, the variable directional antenna 6 is supplied. The supplied DC potential V _ant1 becomes the ground potential. On the other hand, the DC potential V _ant2 is substantially equal to V _ant . Therefore, V _ant1 <V _ant2 , and the directivity of the parasitic element 65 shown in FIG. 4 increases.

By _adopting the configuration of this example, the direct current potential V _ant1 to be supplied to the variable directivity antenna 6 can be controlled only by controlling whether or not the alternating current voltage is superimposed on the direct current voltage that is the voltage value V4 supplied to the antenna unit 2. It becomes possible to control _Vant2 . _Further , the directivity of the variable directivity antenna 6 can be controlled by the supplied DC potentials V _ant1 and V _ant2 . Therefore, it is not necessary to separately provide a switching device such as the switching unit 103 illustrated in FIG. 22, and thus the receiving device 1 can be reduced in size and simplified.

In addition, since the antenna control signal acquisition unit 10c only needs to determine whether or not the AC voltage is superimposed on the DC voltage, detection and determination are performed using simple elements such as the capacitors C6 and C7 and the diode D1. It becomes possible. Therefore, the receiving device 1 can be reduced in size and simplified. In addition, since the fluctuation of the voltage value output from the LPF 25 is small, it is possible to stably output a DC voltage having the voltage value V _amp even if the configuration of the regulator 17 is simplified.

  Further, when the frequency of the alternating voltage superimposed by the oscillating unit 24 is a frequency between the RF signal and the IF signal, the inductors L1 and L2 in which the passage of the RF signal is suppressed can be easily passed. Furthermore, it is possible to suppress the signal to be received from being difficult to demodulate due to the AC signal superimposed by the oscillation unit 24.

  The switch control signal is a pulse signal, and when the signal input to the switch control signal generator 23 varies, the pulse switch control signal is output and the connection of the switch SW2 is switched. It doesn't matter.

  Further, if the antenna control unit 15 is configured to control whether the demodulating unit 3 outputs a DC voltage having a predetermined voltage value or a signal in which the AC voltage is superimposed on the DC voltage, Other configurations may be used. Further, the antenna unit 2 may have another configuration as long as it can detect whether or not the AC voltage is superimposed on the DC voltage.

  Further, the variable directivity antenna 6 may take two or more states as described above. In this case, for example, the amplitude of the AC voltage superimposed on the DC voltage by the oscillating unit 24 may be controlled by the antenna control unit 15, and the time during which the AC voltage is superimposed is controlled by the antenna control unit 15. It doesn't matter. Furthermore, the switch control signal output from the switch control signal generator 23 may be a signal according to the input voltage value or input time. The antenna directivity control unit 7c may be configured to include one or more switches SW2 whose connection is controlled by a switch control signal.

<Fourth embodiment>
Next, the configuration of the receiving apparatus according to the fourth embodiment will be described with reference to FIGS. FIG. 14 is a block diagram showing the configuration of the antenna control signal supply unit of the receiving apparatus in the fourth embodiment, and FIG. 15 shows the output voltage output from the antenna control signal supply section of the receiving apparatus in the fourth embodiment. It is a graph to show. FIG. 16 is a block diagram illustrating configurations of an antenna directivity control unit, a DC voltage generation unit, and an antenna control signal acquisition unit of the receiving apparatus according to the fourth embodiment. FIG. 17 is a graph of signals processed in the antenna control signal acquisition unit of the receiving apparatus in the fourth embodiment.

  As shown in FIG. 14, the antenna control signal supply unit 14d provided in the receiving apparatus 1 of the present example includes a superimposing unit 19 similar to those in the second and third embodiments, and a VCO ( Voltage Controlled Oscillator) 26. The frequency of the AC voltage output from the VCO 26 is controlled by the antenna control unit 15. For example, the frequency of the AC voltage to be output varies according to the voltage value of the signal input from the antenna control unit 15, and the frequency of the AC voltage to be output increases as the input voltage value increases. .

  In this example, as shown in the graph of the output voltage output from the antenna control signal supply unit 14d in FIG. 15, any one of the alternating voltages of the frequencies f1 and f2 (f1 <f2) is output from the VCO 26 to the superposition unit 19. Shall be. Then, the antenna control signal supply unit 14d outputs a signal obtained by superimposing one of the frequencies f1 and f2 on the DC voltage having the voltage value V4.

  As shown in FIG. 16, the DC voltage generator 9d includes an LPF 25 similar to the third embodiment, a regulator 17 similar to the first to third embodiments to which a signal output from the LPF 25 is input, Is provided.

  The antenna control signal acquisition unit 10d includes a capacitor C8 to which a signal output from the antenna control signal supply unit 14c is supplied to one end via the signal line 4, a VCO 27 that oscillates at a frequency f1, and the other end of the capacitor C8. The phase comparator 28 which compares the phase of the signal input from the VCO 27 and the signal input from the VCO 27 and outputs the comparison result as a voltage value, the signal output from the phase comparator 28 and the high frequency component A loop filter 29 to be cut off, a capacitor C9 to which a signal output from the loop filter 29 is supplied to one end, a diode D2 having an anode connected to the other end of the capacitor C9, and one end connected to the cathode of the diode D2. The other end of the capacitor C10 is grounded, and the connection node between the capacitor C10 and the diode D2 is connected. It includes second and third analogously to Example switching control signal generator 23 which de is connected.

  Capacitors C8 and C9 suppress DC components in the input signal. The diode D2 performs half-wave rectification on the AC component input through the capacitor C9. The capacitor C10 smoothes the half-wave rectified AC component and outputs the smoothed AC component to the switch control signal generator 23. With such a configuration, when the signal output from the antenna control signal supply unit 14d is an AC voltage with the frequency f2 superimposed, the switch control signal generation unit 23 has a predetermined voltage value greater than zero. A DC voltage is applied.

  This will be specifically described with reference to FIG. In FIG. 17, for the sake of simplicity, the phase of the AC voltage having the frequency f1 input from the VCO 27 to the phase comparator 28 and the phase when the frequency of the AC voltage input to the phase comparator 28 via the capacitor C8 is f1. And, it is assumed that they are complete. Furthermore, the AC voltage to be compared in the phase comparator 28 is shown as a square wave, and the phase comparator 28 performs phase comparison by taking an exclusive logical ring (XOR) of two input AC voltages. An example will be described.

  As shown in FIG. 17, when the frequency of the input AC voltage before time t1 is both f1, the output of the phase comparison result (XOR) by the phase comparator 28 becomes zero. Therefore, the voltage of the signal output from the loop filter 29 is substantially equal to 0. Then, after time t1, when the frequency of the AC component of the signal input from the demodulator 3 becomes f2, the phase comparison result varies, and the signal output from the loop filter 29 also varies. More specifically, the loop filter 29 outputs an AC voltage having a frequency of f2-f1.

  Therefore, when the DC component of the signal output from the loop filter 29 is suppressed by the capacitor C9, half-wave rectified by the diode D2, and smoothed by the capacitor C10, a predetermined voltage value greater than 0 is applied to the switch control signal generator 23. A DC voltage is applied. When the frequencies of the two AC voltages input to the phase comparator 28 are both f1 and the phases are shifted, the signal output from the loop filter 29 is substantially constant. That is, it becomes substantially equal to the DC voltage and is blocked by the capacitor C9. Therefore, unless the frequencies of the two AC voltages input to the phase comparator 28 are different from each other, a DC voltage having a voltage value greater than 0 is not input to the switch control signal generator 23.

  The antenna directivity control unit 7d includes a booster 18 similar to that in the first to third embodiments and a switch SW2. However, the connection of the switch SW2 is controlled by the switch control signal output from the switch control signal generator 23, as in the second and third embodiments.

In the configuration of the fourth embodiment described above, when the antenna control unit 15 controls the VCO 26 to output a signal in which the alternating voltage of the frequency f1 is superimposed on the direct current voltage of the voltage value V4 from the superimposing unit 19, the antenna control signal acquiring unit A signal having a voltage value substantially equal to 0 is input to the switch control signal generator 23 of 10d. At this time, for example, if a switch control signal indicating that the terminal S1 and the contact T1, and the terminal S2 and the contact T3 are connected is output from the switch control signal generation unit 23 to the switch SW2, The supplied DC potential V _ant1 is substantially equal to V _ant . On the other hand, the DC potential V _ant2 becomes the ground potential. Therefore, V _ant1 > V _{ant2 and} the directivity of the parasitic element 66 shown in FIG. 4 is increased.

When the antenna control unit 15 controls the VCO 26 to output a signal in which the alternating voltage of the frequency f2 is superimposed on the direct current voltage of the voltage value V4 from the superimposing unit 19, the switch control signal generating unit of the antenna control signal acquiring unit 10d A DC voltage having a voltage value greater than 0 is input to 23. At this time, for example, if a switch control signal for connecting the terminal S1 and the contact T2, and the terminal S2 and the contact T4 is output from the switch control signal generating unit 23 to the switch SW2, the variable directional antenna 6 is supplied. The supplied DC potential V _ant1 becomes the ground potential. On the other hand, the DC potential V _ant2 is substantially equal to V _ant . Therefore, V _ant1 <V _ant2 , and the directivity of the parasitic element 65 shown in FIG. 4 increases.

By adopting the configuration of this example, the frequency of the AC voltage to be superimposed on the DC voltage that is the voltage value V4 supplied to the antenna unit 2 is selected from f1 and f2 and output to the variable directivity antenna 6 The DC potentials V _ant1 and V _ant2 can be controlled. _Further , the directivity of the variable directivity antenna 6 can be controlled by the supplied DC potentials V _ant1 and V _ant2 . Therefore, it is not necessary to separately provide a switching device such as the switching unit 103 illustrated in FIG. 22, and thus the receiving device 1 can be reduced in size and simplified.

Even if the frequencies f1 and f2 are different, the fluctuation of the voltage value output from the LPF 25 is small. Therefore, even if the configuration of the regulator 17 is simple, a DC voltage that stably becomes the voltage value V _amp is output. It becomes possible to do. Furthermore, since fluctuations at the time of switching between the frequencies f1 and f2 are reduced, it is possible to suppress the occurrence of noise and the like.

  Further, when the frequencies f1 and f2 of the alternating voltage superimposed by the VCO 26 are the frequencies between the RF signal and the IF signal, it is possible to easily pass the inductors L1 and L2 in which the passage of the RF signal is suppressed. Furthermore, it is possible to prevent the signal to be received from being difficult to demodulate due to the AC signal superimposed by the VCO 26.

  The switch control signal is a pulse signal, and when the signal input to the switch control signal generator 23 varies, the pulse switch control signal is output and the connection of the switch SW2 is switched. It doesn't matter.

  Other configurations may be used as long as the antenna control unit 15 is controlled so that the frequency of the AC component of the signal output from the demodulation unit 3 is either f1 or f2. Further, the antenna unit 2 may have another configuration as long as it can detect whether or not the frequency of the AC component superimposed on the DC voltage is f1.

  Further, the variable directivity antenna 6 may take two or more states as described above. In this case, for example, the frequency of the AC voltage superposed on the DC voltage by the VCO 26 may be variable, and the frequency may be controlled by the antenna control unit 15. Furthermore, the switch control signal output from the switch control signal generator 23 may be in accordance with the input voltage value. The antenna directivity control unit 7d may be configured to include one or more switches SW2 whose connection is controlled by a switch control signal.

<Fifth embodiment>
Next, the configuration of the receiving apparatus in the fifth embodiment will be described with reference to FIGS. FIG. 18 is a block diagram showing the configuration of the antenna control signal supply unit of the receiving apparatus in the fifth embodiment, and FIG. 19 shows the output voltage output from the antenna control signal supply section of the receiving apparatus in the fifth embodiment. It is a graph to show. FIG. 20 is a block diagram illustrating configurations of an antenna directivity control unit, a DC voltage generation unit, and an antenna control signal acquisition unit of the receiving apparatus according to the fifth embodiment. FIG. 21 is a graph of signals processed in the antenna control signal acquisition unit of the receiving apparatus in the fifth embodiment.

  As shown in FIG. 18, the antenna control signal supply unit 14e provided in the receiving device 1 of the present example includes a superimposing unit 19 similar to the second to fourth examples, an oscillation unit 24 similar to the third example, The 180 ° phase changing unit 30 that shifts the phase of the AC voltage superimposed on the DC voltage by the oscillating unit 24 by 180 °, and whether or not the oscillating unit 24 is connected to the superposing unit 19 via the 180 ° phase changing unit 30. And a switch SW5 that is determined and controlled by the antenna control unit 15.

  When the connection is switched by the switch SW5, the 180 ° phase changing unit 30 is connected to or disconnected from the superimposing unit 19. Then, every time the switch SW5 is switched, the phase of the AC voltage superimposed on the DC voltage in the superimposing unit 19 is shifted by 180 °. Therefore, as shown in the graph of the output voltage output from the antenna control signal supply unit 14e in FIG. 19, the voltage output from the antenna control signal supply unit 14e is superimposed on the DC voltage of the voltage value V4. At the same time, the phase of the superimposed AC voltage can be shifted by 180 ° during the output.

  As shown in FIG. 20, the DC voltage generator 9e includes an LPF 25 similar to the third and fourth embodiments and a regulator similar to the first to fourth embodiments to which a signal output from the LPF 25 is input. 17.

  The antenna control signal acquisition unit 10e includes a capacitor C8, a VCO 27, a phase comparator 28, a loop filter 29, and a switch control signal generation unit 23 similar to those in the fourth embodiment. However, in this example, the signal output from the loop filter 29 is input to the switch control signal generator 23.

  The signal output from the loop filter will be described with reference to FIG. Here, similarly to FIG. 17 shown for the fourth embodiment, the phase of the AC voltage input from the VCO 27 to the phase comparator 28 and the phase of the AC voltage input to the phase comparator 28 via the capacitor C8 Are arranged before time t2. The AC voltage to be compared in the phase comparator 28 is shown as a square wave, and the phase comparator 28 performs phase comparison by taking an exclusive logical ring (XOR) of two input AC voltages. explain.

  As shown in FIG. 21, since the phase of the input AC voltage is uniform before time t2, the output of the phase comparison result (XOR) by the phase comparator 28 becomes zero. Therefore, the voltage of the signal output from the loop filter 29 is substantially equal to 0. Then, after time t2, when the switch SW5 is switched and the phase of the AC component of the signal output from the antenna control signal supply unit 10e is shifted by 180 °, the phase comparison result and the signal output from the loop filter 29 are changed to t2. It will be different from before. More specifically, the voltage value of the DC voltage output from the loop filter 29 is different before and after time t2.

  The antenna directivity control unit 7e includes a booster 18 similar to that in the first to fourth embodiments and a switch SW2. However, the connection of the switch SW2 is controlled by the switch control signal output from the switch control signal generator 23, as in the second to fourth embodiments.

  In the configuration of the fifth embodiment described above, for example, the directivity of the parasitic element 66 of the variable directivity antenna 6 shown in FIG. A case of switching so as to increase will be described. At this time, first, the antenna control unit 15 performs control to switch connection of the switch SW5. Then, the phase of the AC component of the signal output from the antenna control signal supply unit 14e is shifted by 180 °. Then, the voltage value of the DC voltage output from the loop filter 29 and input to the switch control signal generator 23 varies. The switch control signal generator 23 outputs a switch control signal for switching the connection of the switch SW2 in accordance with the fluctuation of the voltage value of the input DC voltage.

Before the switch SW2 connection is switched, the terminal S1 and the contact T1, and the terminal S2 and the contact T3 are connected to each other. However, the terminal S1 and the contact T2, and the terminal S2 and the contact T4 are connected by switching the connection. It becomes a state. As a result, the DC potential V _ant1 supplied to the variable directivity antenna 6 becomes the ground potential, and the DC potential V _ant2 becomes substantially equal to V _ant . Therefore, V _ant1 <V _ant2 , and the directivity of the parasitic element 65 shown in FIG. 4 increases.

The same applies to increasing the directivity of the parasitic element 66. First, the antenna control unit 15 performs control to switch connection of the switch SW5. Similarly, based on the change in the voltage value of the DC voltage output from the loop filter 29, the switch control signal generator 23 outputs a switch control signal for switching the connection of the switch SW2. As a result, the connection of the switch SW2 is switched, and V _ant1 > V _{ant2 is satisfied} , and the directivity of the parasitic element 66 is increased.

With the configuration of this example, the DC potential V _ant1 supplied to the variable directivity antenna 6 can be output only by shifting the phase of the AC voltage superimposed on the DC voltage that is the voltage value V4 supplied to the antenna unit 2. It becomes possible to control _Vant2 . _Further , the directivity of the variable directivity antenna 6 can be controlled by the supplied DC potentials V _ant1 and V _ant2 . Therefore, it is not necessary to separately provide a switching device such as the switching unit 103 illustrated in FIG. 22, and thus the receiving device 1 can be reduced in size and simplified.

Further, since the frequency of the AC voltage to be superimposed on the DC voltage can be made constant, the fluctuation of the voltage value output from the LPF 25 can be reduced, and the optimization of the LPF 25 is facilitated. Therefore, even if the configuration of the regulator 17 is simplified, it is possible to stably output a DC voltage having the voltage value V _amp .

  Further, when the frequency of the alternating voltage superimposed by the oscillating unit 24 is a frequency between the RF signal and the IF signal, the inductors L1 and L2 in which the passage of the RF signal is suppressed can be easily passed. Furthermore, it is possible to prevent the signal to be received from being difficult to demodulate due to the AC signal superimposed by the oscillating unit 24.

  Note that immediately after the operation of the receiver 1 is started, the VCO is synchronized so that the phase of the AC voltage input to the phase comparator 28 via the capacitor C8 and the phase of the AC voltage output from the VCO 27 are aligned. It does not matter. With this configuration, when the phase of the AC voltage to be superimposed on the DC voltage is changed by 180 ° by switching the switch SW5, the voltage value difference before and after switching of the DC voltage output from the loop filter 29 can be maximized. it can. For this reason, the switch control signal generator can easily recognize the fluctuation of the DC voltage, and the malfunction can be suppressed.

  Further, although the 180 ° phase changing unit 30 shifts the phase of the AC voltage superimposed on the DC voltage by 180 °, the phase may be shifted by another angle such as 90 ° or 120 °.

  In addition, the switch control signal is a pulse signal, and when the signal input to the switch control signal generator 23 varies, the pulse switch control signal is output and the connection of the switch SW2 is switched. It doesn't matter.

  Further, any other configuration may be used as long as the antenna control unit 15 can shift the phase of the AC component of the signal output from the demodulation unit 3 while it is being output. Further, the antenna unit 2 may have another configuration as long as it can detect that the phase of the AC component superimposed on the DC voltage is shifted.

  Further, the variable directivity antenna 6 may take two or more states as described above. In this case, for example, in addition to the 180 ° phase changing unit 30, the phase may be shifted by 60 ° or 120 °. Further, assuming that the two signals input to the phase comparator 28 are synchronized when not passing through the phase changing unit, a DC voltage having a voltage value corresponding to the shifted phase is output from the loop filter 29. It doesn't matter. The antenna directivity control unit 7e may be configured to include one or more switches SW2 whose connection is controlled by a switch control signal.

<< Other Examples >>
Although the above-described embodiment relates to the reception device 1, the antenna control device and the antenna control method of the present invention may be used for control of a variable directivity antenna used for a transmission device or the like. When used in a transmission apparatus, the directivity in the transmission direction can be controlled.

  In the above-described receiving device 1, the operation of the antenna control unit 15 may be performed by a control device such as a microcomputer. Further, all or part of the functions realized by such a control device is described as a program, and the program is executed on a program execution device (for example, a computer) to realize all or part of the functions. It doesn't matter if you do.

  In addition to the above-described case, the above-described receiving device 1 can be realized by hardware or a combination of hardware and software. When the receiving device 1 is configured using software, a block diagram of a part realized by software represents a functional block diagram of the part.

  As mentioned above, although each embodiment in the present invention was described, the range of the present invention is not limited to this, and can be carried out by adding various changes without departing from the gist of the invention.

  The present invention relates to an antenna control device provided in a communication device such as a transmission device or a reception device that performs wireless communication using electromagnetic waves typified by broadcasting radio waves such as terrestrial digital television broadcasting and terrestrial digital audio broadcasting. .

These are block diagrams which show the structure of the receiver in embodiment of this invention. These are block diagrams which show an example of a structure of a variable directivity antenna. These are block diagrams which show an example of a structure of a variable directivity antenna. These are block diagrams which show an example of a structure of a variable directivity antenna. These are block diagrams which show the structure of the antenna control signal supply part of the receiver in 1st Example. These are the graphs which show the output voltage output from the antenna control signal supply part of the receiver in 1st Example. These are block diagrams which show the structure of the antenna directivity control part, direct-current voltage generation part, and antenna control signal acquisition part of the receiver in 1st Example. These are block diagrams which show the structure of the antenna control signal supply part of the receiver in 2nd Example. These are the graphs which show the output voltage output from the antenna control signal supply part of the receiver in 2nd Example. These are block diagrams which show the structure of the antenna directivity control part of the receiving apparatus in 2nd Example, a DC voltage generation part, and an antenna control signal acquisition part. These are block diagrams which show the structure of the antenna control signal supply part of the receiver in 3rd Example. These are the graphs which show the output voltage output from the antenna control signal supply part of the receiver in 3rd Example. These are block diagrams which show the structure of the antenna directivity control part, direct-current voltage generation part, and antenna control signal acquisition part of the receiver in 3rd Example. These are block diagrams which show the structure of the antenna control signal supply part of the receiver in 4th Example. These are the graphs which show the output voltage output from the antenna control signal supply part of the receiver in 4th Example. These are block diagrams which show the structure of the antenna directivity control part, direct-current voltage generation part, and antenna control signal acquisition part of the receiver in 4th Example. These are the graphs of the signal processed in the antenna control signal acquisition part of the receiver in 4th Example. These are block diagrams which show the structure of the antenna control signal supply part of the receiver in 5th Example. These are the graphs which show the output voltage output from the antenna control signal supply part of the receiver in 5th Example. These are block diagrams which show the structure of the antenna directivity control part of the receiving apparatus in 5th Example, a DC voltage generation part, and an antenna control signal acquisition part. These are the graphs of the signal processed in the antenna control signal acquisition part of the receiver in 5th Example. These are block diagrams which show the structure of the conventional receiver.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Receiving device 2 Antenna part 3 Demodulation part 4 Signal line 5 Video audio processing part 6, 6a-6c Variable directional antenna 61, 62 Directional antenna 63 Antenna selection part 64 Power feeding / receiving element 65, 66 Parasitic element 7, 7a-7e Antenna directivity control unit 8 LNA
9, 9a to 9e DC voltage generation unit 10, 10a to 10e Antenna control signal acquisition unit 11 Tuner unit 12 Demodulator 13 DC power source 14, 14a to 14e Antenna control signal supply unit 15 Antenna control unit 16 Voltage variable regulator 17 Regulator 18 Booster Device 19 Superimposition unit 20 DC power supply 21 Pulse generation unit 22 Pulse detection unit 23 Switch control signal generation unit 24 Oscillation unit 25 LPF
26, 27 VCO
28 Phase Comparator 29 Loop Filter 30 180 ° Phase Changer L1-L2 Inductor R1-R10 Resistor D1, D2 Diode VD1, VD2 Varactor Diode C1-C10 Capacitor SW1-SW5 Switch

Claims (9)

An antenna provided in a communication apparatus, comprising: an antenna unit provided with a variable directivity antenna that wirelessly communicates a signal and whose directionality in a communication direction is variable; and a signal conversion unit that converts a signal input to and output from the antenna unit In the control device,
An antenna control signal supply unit that is provided in the signal conversion unit and that supplies an antenna control signal for controlling the directivity of the variable directivity antenna to the antenna unit by superimposing the antenna control signal on a DC voltage;
An antenna directivity control unit that is provided in the antenna unit and outputs a signal for controlling the directivity of the variable directivity antenna to the variable directivity antenna;
An antenna control signal acquisition unit that is provided in the antenna unit and controls the antenna directivity control unit based on an antenna control signal included in a signal supplied from the antenna control signal supply unit;
An antenna control device comprising:   The antenna directivity control unit controls the directivity of the variable directivity antenna by outputting a DC voltage obtained by converting the signal supplied from the antenna control signal supply unit to the variable directivity antenna. The antenna control apparatus according to claim 1.   The receiving apparatus according to claim 1, wherein the antenna control signal is a DC signal and is a signal that can take at least two states having different voltage values.   3. The reception according to claim 1, wherein the antenna control signal is a signal that can take a state in which a voltage value fluctuates in a pulse shape and a direct current state in which a predetermined voltage value is obtained. apparatus.   The receiving apparatus according to claim 1, wherein the antenna control signal is a signal that can take an AC state having a predetermined frequency and a DC state having a predetermined voltage value. .   The receiving apparatus according to claim 1, wherein the antenna control signal is an AC signal and is a signal that can take at least two states having different frequencies.   The receiving apparatus according to claim 1, wherein the antenna control signal is an AC signal having a predetermined frequency and is a signal that can take at least two states having different phases. In a receiving device including an antenna unit that includes an antenna that receives a signal and whose directivity in a reception direction is variable, and a demodulation unit that demodulates a signal input to the antenna unit,
An antenna control signal supply unit that is provided in the demodulation unit and supplies an antenna control signal that controls the directivity of the variable directivity antenna to the antenna unit by superimposing it on a DC voltage;
An antenna directivity control unit that is provided in the antenna unit and outputs a signal for controlling the directivity of the variable directivity antenna to the variable directivity antenna;
An antenna control signal acquisition unit for controlling the antenna directivity control unit based on an antenna control signal provided in the antenna unit and superimposed on a signal supplied from the antenna control signal supply unit;
A receiving apparatus comprising: In an antenna control method for a communication apparatus, comprising: an antenna unit that includes an antenna that wirelessly communicates a signal and whose directionality in a communication direction is variable; and a signal conversion unit that converts a signal input to and output from the antenna unit.
An antenna control signal for controlling the directivity of the variable directivity antenna is superimposed on a DC voltage and supplied to the antenna unit,
The antenna control method, wherein the antenna unit controls the variable directivity antenna based on an antenna control signal included in a supplied signal.

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