JPH0884015A - Antenna - Google Patents

Abstract

PURPOSE: To make effective beam pointing possible for a portable antenna or an antenna for moving body in accordance with easy operation procedures with a simple constitution by changing the radiation directivity so as to gradually stepwise or continuously raise the directivity gain. CONSTITUTION: Low-noise amplifiers(LNA) 1003 to 1005 are connected to antenna elements 1000 to 1002 respectively. Variable phase shifters 1006 to 1008 and switches 1009 to 1011 are connected following LNAs, and extents of phase shift of variable phase shifters and on/off of switches are set by the control signal generated from a control circuit 1013. When the switch is turned on, a reception signal is synthesized in a synthesizer 1012 and is inputted to a reception equipment 1014. When the switch is turned off, terminals on the antenna side and the synthesizer side are connected to a reflectionless terminal 1039. Thus, the antenna beam is gradually sharpened to raise the gain, and finally, the beam having a desired gain is directed to the radio wave coming direction.

Description

Detailed Description of the Invention

[0001]

This invention relates to mobile communication, satellite communication,
The present invention relates to an antenna used for satellite broadcasting.

[0002]

2. Description of the Related Art In a high-gain antenna used for satellite communication, satellite broadcasting, etc., it is required to accurately match the beam direction with the arrival and emission directions of the radio waves. When the antenna is used by fixing it in one place, there is no problem because the beam direction may be set accurately first even if a slightly complicated and large-scale method is used. However, it is important to easily perform such beam pointing by a simple method when it is used for carrying or mounting on a moving body. The following methods can be considered as beam pointing methods that have been conventionally considered.

The beam is scanned to find the direction in which the received radio wave level is maximum, and the antenna is fixed in that direction.

The arrival direction of the radio wave is detected by some kind of sensor, and the beam direction of the antenna is set based on the information.

In the method (1), it is necessary to scan the beam in order to detect the arrival direction of the radio wave, and the scanning time is long, which is a practical problem. In particular, when the antenna gain is high, the beam width becomes considerably narrow, so the beam must be scanned finer. If the arrival of radio waves and the direction of radiation are known to some extent, such a method can be used, but if the arrival of radio waves and the direction of emission are constantly changing, such as when mounted on a mobile unit. Since it is necessary to scan the beam in all directions, it is difficult to practically use this method. Further, if the beam scanning is roughly performed, it is possible that an error may occur in which the peak value of the side lobe is erroneously matched with the arrival direction of the radio wave. In this method, a magnetic sensor or a monopulse sensor can be considered as a sensor.However, this method requires a configuration in which a sensor other than the antenna is provided and the beam direction of the antenna is controlled by that information, which complicates the configuration. become. Further, also in the sensor, the magnetic sensor is used only when the direction of arrival of the radio wave is in a certain azimuth direction, such as when communicating with a geostationary satellite, and the range of use is limited. Further, in this case, since the direction of arrival of the radio wave is detected by using an indirect means called magnetism, there is a problem in accuracy. In particular, this is a problem in the case of a high gain antenna having a narrow beam width. Also,
When the monopulse sensor is used, the arrival direction of the radio wave can be accurately determined after the arrival direction of the radio wave is narrowed down to a certain angle region. However, other means (a method of performing beam scanning or a method of using another sensor) is required until the arrival direction of the radio wave is narrowed down to a certain angle region. As a result, the configuration, control procedure, etc. are complicated, and there is a cost problem.

[0006]

As described above, according to the conventional beam pointing method, when it is applied to a high gain antenna, time-consuming beam scanning or
It is necessary to provide another sensor, which causes problems such as a complicated antenna configuration and an increase in cost. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide an antenna capable of performing effective beam pointing on an antenna for a mobile device or a mobile device with a simple configuration and operation procedure.

[0007]

In order to achieve the above object, the antenna of the first invention of the present application comprises means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously. It is characterized by having.

The antenna of the second invention of the present application is the antenna of the first invention.
In the antenna according to the invention, as a means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, the antenna element is composed of a plurality of antenna elements, and the antenna element combines or distributes radio waves. Is connected to the antenna element and the power supply circuit, and a switch and a variable phase shifter for transmitting and blocking radio waves between the antenna element and the power supply circuit are provided, and the switch and the variable phase shifter are connected to a CPU. It is characterized by being controlled by.

Further, the antenna of the second invention of the present application is characterized in that a variable amplifier is added and connected between the feeding circuit and the antenna element.

The antenna of the third invention of the present application is the above first antenna.
In the antenna according to the invention, as a means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, the antenna element is composed of a plurality of antenna elements, and the antenna element combines or distributes radio waves. And a variable amplifier and a variable phase shifter are provided between the antenna element and the power feeding circuit, and the variable amplifier and the variable phase shifter are controlled by a CPU.

Further, the antenna of the second or third invention of the present application is separately provided for transmission and reception, and the common CPU controls the variable phase shifter.

Further, in a configuration in which the antenna of the second or third invention of the present application is separately provided for transmission and reception, and the common CPU controls the variable phase shifter, the antenna element can be used for transmission and reception. Characterized by sharing.

In the first modification of the antenna of the second or third invention of the present application, the control by the CPU is
It has a function of monitoring and storing the level of a signal received from the receiver, and performs control for gradually increasing the directional gain, and as the control for gradually increasing the directional gain, the switch is turned on or The number of antenna elements to be operated is increased by increasing the amplification factor of the amplifier, and the phase amount that maximizes the received signal level is obtained by changing the phase amount of only the variable phase shifter connected to the increased antenna elements. Obtained, performing an operation procedure for setting the phase amount that maximizes the received signal level in the variable phase shifter, increase the number of antennas that sequentially operate the operation procedure, and repeat until there are no antenna elements that do not operate. To do.

A second modified example of the second or third invention of the present application includes the first modified example thereof, and a plurality of antenna elements are operated at once in the initial stage of control by the CPU. , A phase amount that maximizes a received signal level is obtained by changing the phase amount of the variable phase shifter connected to the antenna elements that are operated at one time,
An operation procedure for setting a phase amount that maximizes the received signal level in the variable phase shifter is performed, and thereafter, control for gradually increasing the directional gain is performed.

The third modification of the second or third invention of the present application includes the first modification thereof, and the number of antenna elements is increased in the control for gradually increasing the directional gain. The maximum received signal level at each stage is stored, the received signal level at the final stage is stored,
When the received signal level falls below the received signal level in the final step, the number of antenna elements to be gradually operated is decreased, and the received signal level at this time is the maximum received signal in the corresponding number of antenna elements at each step stored. When it is determined that the level is equal to the level, the control for gradually increasing the directivity gain is restarted.

A fourth modification of the second or third invention of the present application includes the first modification, and a desired value of the received signal level is set in advance and exceeds the desired value. In the step, the control for gradually increasing the directivity gain is finished.

The fifth modified example of the second or third invention of the present application includes the first modified example, and finely adjusts the phase amounts of all the variable phase shifters in the final stage. The phase distribution that maximizes the received signal level is obtained, and this value is set in the corresponding variable phase shifter.

A sixth modified example of the second or third invention of the present application includes the first modified example, and in addition to the received signal level, a received signal level of an interfering wave is also monitored, In the control for gradually increasing the directivity gain, the phase amount of the variable phase shifter is controlled so as to raise a desired received signal level and lower a received signal level of an interfering wave.

The seventh modification of the second or third invention of the present application includes the first modification thereof, and in the control for gradually increasing the directivity gain, the antenna element to be increased is The feature is that the size of the aperture of the operating antenna is selected to be gradually increased.

The antenna of the fourth invention of the present application is the antenna of the first invention.
In the antenna according to the invention, as a means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, in the reflector antenna, a shield for blocking a part of the radio wave reflected by the reflector The shield plate has a structure in which a region for blocking radio waves can be changed by a drive unit, and has an antenna drive unit for driving the entire antenna or a part of a mirror surface system. The unit is controlled by the CPU.

In a modification of the antenna of the fourth invention of the present application, the CPU monitors the level of a received signal from the receiver and gradually reduces the effective aperture area of the antenna stepwise. The driving unit is controlled to move the shielding plate, the antenna driving unit is driven at each stage to scan the antenna beam, and the antennas are controlled so as to be aligned in the direction in which the received signal level is maximized. .

The antenna of the fifth invention of the present application is the above-mentioned first antenna.
In the antenna of the invention, the antenna using a reflect array as the means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, the reflect array faces the primary radiator. A plurality of antenna elements, a switch and a variable phase shifter connected to each of the antenna elements, the CPU controls the switch and the variable phase shifter, and when the switch is OFF, It is characterized in that the antenna element is connected to the non-reflection end side, and when ON, the antenna element is connected to the line side where the variable phase shifter is connected and the end is opened or short-circuited.

The antenna of the sixth invention of the present application is the same as the first invention.
In the antenna according to the invention, as a means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, in an array antenna composed of a plurality of antenna elements, each antenna element is combined, It has a power supply circuit for distribution, the power supply circuit is formed by using a waveguide or a radial waveguide, and a radio wave absorber or a short-circuit plate is inserted inside the waveguide or the radial waveguide, or the position is changed. It is characterized in that it has a driving unit for changing it, and has an antenna driving unit for driving the entire antenna.

[0024]

In the first invention of the present application, the radiation directivity is changed stepwise or continuously so as to gradually increase the directivity gain, and in the first step, a beam having a wide beam width is scanned. The beam is roughly matched with the arrival direction and the emission direction of the radio wave, and the beam is gradually matched with the arrival direction and the emission direction of the radio wave by the beam having a narrow beam width.

Here, as in the second invention of the present application, it is composed of a plurality of antenna elements, a switch and a variable phase shifter are provided between the antenna element and the power feeding circuit, and the switch is turned on by the control of the CPU. By setting the antenna element in the operating state, the beam width of the antenna can be gradually narrowed and the directional gain can be increased. Also, CP
By controlling the variable phase shifter by U, the beam is scanned, and the direction in which the directional gain is maximum and the arrival direction of the radio wave are
Radiation directions can be matched.

Further, as in the third invention of the present application, a variable amplifier and a variable phase shifter, which are composed of a plurality of antenna elements and are provided between the antenna elements and the feeding circuit,
By controlling the antenna element that raises the amplification factor of the variable amplifier under the control of the CPU, the beam width of the antenna can be gradually narrowed and the directional gain can be increased. Further, the beam can be scanned by controlling the variable phase shifter by the CPU, and the direction in which the directional gain is maximum can be made to coincide with the arrival direction and the emission direction of the radio wave.

Further, as in the fourth invention of the present application, the reflector antenna has a shield plate for shielding a part of the radio wave reflected by the reflector, and the shield plate shields the radio wave by the drive unit. By adopting a structure in which the cutoff region can be changed, the beam width of the antenna can be gradually narrowed and the directional gain can be increased. In addition, the beam direction can be freely changed by providing an antenna drive unit that drives the entire antenna or a part of the mirror surface system. CP for the drive unit and the antenna drive unit
By controlling by U, the beam direction can be made to coincide with the radio wave direction while gradually increasing the directivity gain.

Further, in the antenna using the reflect array as in the fifth invention of the present application, the reflect array is arranged so as to face the primary radiator to perform the same operation as the reflector antenna. By configuring the reflect array with a plurality of antenna elements, switches and variable phase shifters respectively connected to the antenna elements, and controlling the switches and variable phase shifters by the CPU,
The switch controls the range of operation as a reflecting mirror to gradually narrow the beam width and gradually increase the directional gain, and the variable phase shifter allows the beam direction to be set freely. . Therefore, the CPU can control the antenna so that the beam direction coincides with the radio wave direction while gradually increasing the directional gain.

Further, as in the sixth invention of the present application, in the array antenna composed of a plurality of antenna elements, a feeding circuit for synthesizing and distributing each antenna element is provided, and this feeding circuit is connected. The beam of the antenna is formed by using a wave tube or a radial waveguide, and by inserting a radio wave absorber or a short-circuit plate inside the waveguide or the radial waveguide, or by having a drive unit for changing the position. The width can be gradually narrowed to increase the directional gain. In addition, the beam direction can be freely changed by providing an antenna drive unit that drives the entire antenna.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention using an array antenna will be described below with reference to the drawings.

FIG. 1 is a block diagram of an antenna showing a first embodiment of the present invention. Here, the antenna is provided with a plurality of antenna elements 1000, 1001, 1002, and each antenna element has an LNA (low noise amplifier) 1003, 10
04 and 1005 are respectively connected. After the LNA, variable phase shifters 1006, 1007, 1008 and switches 1009, 1010, 1011 are respectively connected, and the phase amount of the variable phase shifter and ON / OFF of the switch are controlled by a control signal generated from the control circuit 1013. OFF is set. When the switch is ON, the received signals are combined by the combiner 1012 and then input to the receiving device 1014. When the switch is OFF, in order to prevent re-radiation and to prevent the influence on the combiner, the terminal on the antenna side,
Both terminals on the synthesizer side are connected to the non-reflection terminal 1039.
The CPU 1015 gives commands to the control circuit regarding the phase amount of the variable phase shifter and ON / OFF of the switch, based on a signal (for example, a reception intensity signal) representing the reception state in the reception device. Here, the control signal generated by the control circuit is, for example, a bias voltage for changing ON / OFF of the diode switch. A feature of the configuration of this antenna is that only a received signal from a required antenna element can be taken out by a switch, and a certain phase amount can be set to the received signal by a phase shifter to combine them. By using this configuration, it becomes possible to gradually sharpen the beam of the antenna, increase the gain, and finally direct the beam of the desired gain in the arrival direction of the radio wave. Next, the procedure of the operation will be described.

FIG. 2 is a flowchart showing an example of an operation procedure in the antenna of FIG. 1 which is the first embodiment. This operation procedure shows a control method in the CPU 1015. In the initial state, it is assumed that only the reference antenna element is in operation (this antenna element may be turned on at the beginning of all operations). Next, the switches of the antenna elements to be operated are turned from OFF to ON, and the number of operating antenna elements is gradually increased. At this time, the phase of the phase shifter connected to the increased antenna element is controlled to be changed. Here, the reception signal level in the process of changing the phase amount is obtained from the receiving device and stored. While changing the phase amount, the condition that maximizes the received signal level is selected, and this phase amount is set in the phase shifter. At this stage, a signal level higher than the received signal level in the initial state is obtained. Next, the number of antenna elements to be further operated is increased, and the phase amount of the phase shifter corresponding to the increased antenna elements is set by the same procedure. Finally, the procedure ends when there are no unused antenna elements. Finally, the large received signal level obtained with all antenna elements is achieved. After this, communication etc. will be started. Of course, the procedure of increasing the number of operating antenna elements and setting the phase may be performed in the communication state.

FIG. 3 shows how the antenna pattern changes in the course of this procedure. For the sake of simplicity, it is considered that the three antenna elements 1101, 1102, 1103 are arranged in a straight line, and the radio wave arrival direction comes from an inclined direction as shown in FIG. (A) In the initial state, only the antenna element 1101 operates and the signal is transmitted to the receiving device 1106. The antenna pattern at this stage is a very wide-angle beam because only one antenna element is operating. In the next (b) first step, the switch of the antenna element 1102 is newly turned on. Antenna element 110
The received signal at 2 passes through the phase shifter 1104, is combined with the signal with the antenna element 1101 by the combiner 1105, and is transmitted to the receiving device. At this stage, as shown in the figure, the antenna pattern has a sharper beam than that in the previous stage. The direction of this beam can be changed by changing the phase amount of the phase shifter 1104. By constantly grasping and storing the received signal level in the process of changing the phase amount of the phase shifter 1104, it is possible to determine at which phase amount the maximum received signal is obtained. The phase amount at this time is calculated by the phase shifter 1104.
By setting to, a beam with a higher gain than in the previous stage is directed in the direction of arrival of radio waves. Further, in the second step (c), the last remaining antenna element 1103 is also turned on and operated. The phase shifter 1107 sets the phase amount of the reception signal of the antenna element 1103, and the combiner 1105
Are combined with the reception signals of other antenna elements and transmitted to the receiving device. In this step, the phase shifter 1104 is fixed to the amount set in the previous step, and the phase shifter 110
The phase amount of 7 is changed. The antenna pattern is sharper and has a higher gain than the previous step. Therefore,
When the antenna element 1103 is turned on, there is a possibility that the beam direction and the arrival direction of the radio wave may deviate due to the narrowing of the beam width. A matched pattern is formed. Here, by changing the phase amount of the antenna element 1103, the phase amount for completely matching the beam direction with the radio wave direction can be obtained by the same method as in the previous step.

With the above antenna configuration and control method, the number of antenna elements to be operated is gradually increased while setting the phase amount of the variable phase shifter so that the received signal level becomes maximum or maximum. Therefore, it is possible to gradually increase the directivity of the antenna, which was initially broad, toward the arrival direction of the radio wave, and increase the gain. Here, the following effects can be expected.

In the conventional method, the arrival direction of the radio wave is obtained by another antenna or sensor, and this information is input to a phase shifter, a mechanical drive system or the like so that the beam direction of the antenna is the arrival direction of the radio wave. However, if the configuration and control method of the present invention is used, no special device for detecting the arrival direction of the radio wave is required, and the antenna configuration can be greatly simplified. Therefore, it is also effective for cost reduction.

When the location where the antenna is used, such as a portable antenna, is frequently changed, the conventional method of inputting the information of the direction of arrival of the radio wave by some method does not bother the beam pointing adjustment when the antenna is installed. Very problematic. The antenna of the present invention capable of controlling the beam direction completely electrically has no such troublesomeness,
It has a great effect as an application to such an antenna.

By gradually increasing the number of antennas to be operated and changing the antenna beam from a broad one to a sharp one, beam pointing can be performed reliably and accurately. For example, when all the antenna elements are operated at the same time, the arrival direction of the radio wave may erroneously coincide with the maximum value of the side lobe. There is no. In order to increase this effect, it is advisable to increase the number of elements so that the size of the effective aperture of the entire antenna is gradually increased in the process of increasing the number of operating antennas.

In the conventional method of operating all the antenna elements at the same time and controlling the phase amount thereof, the scanning range and the number of times for beam capturing are extremely large in order to form a beam having a very narrow beam width from the beginning. It takes a long time to capture the beam. However, due to the configuration and operating procedure of the antenna in the first embodiment of the present invention, it is possible to efficiently capture a beam in the arrival direction of a radio wave in a very short time. Also, regarding the phase control, since it may be performed in order for one or at most several antenna elements,
The control method and its configuration are also very simple.

In the antenna of the present invention shown in the first embodiment, the configuration and operating procedure of the antenna are not limited to the above examples. Next, other examples will be described.

FIG. 4 is a flow chart showing another example of the operation procedure of the antenna of the present invention in the first embodiment. In this operation procedure, a certain number of antenna elements are collectively operated in the initial stage (O
Set to N) (S1). By controlling the phase amount of the antenna element operating at this stage, the beam of the antenna is scanned over the range in all directions (S2). Here, by constantly grasping the received signal level (S3), the distribution of the phase amount that maximizes the received signal level is obtained, and the phase amount is set in each antenna element. At this stage, the arrival direction of the radio wave can be captured with a beam pattern having a certain gain. Next, similarly to the operation procedure shown in FIG.
The number of antenna elements to be operated is increased one by one (or at most several), and the phase amount is controlled (the phase amount set in the previous stage is fixed) to maximize the received signal level. The condition is obtained (S4), and the phase amount is set for the newly operated antenna element (S5). By repeating such a procedure as S5 to S9, finally all the antenna elements are operated, the antenna pattern is oriented in the arrival direction of the radio wave, and the gain is maximized.

The operation procedure example of FIG. 4 is effective when the incoming radio waves are very weak such as satellite communication and satellite broadcasting, and a high gain antenna is required for the reception. That is, first, a beam with the gain necessary for detecting the received signal is formed, and then this beam is scanned to capture the beam to some extent. You can do it well. The first stage beam scanning requires a wide range of scanning,
Since a broad beam having the lowest gain capable of detecting the received signal is used, the scanning time is not so long. Therefore, even with a high-gain antenna, efficient and reliable beam capture is possible. Very effective as an antenna for satellite communications and satellite broadcasting.

In the case of this operation procedure example, how many elements are operated first is an important issue. If the number of elements is too small, the received signal cannot be detected,
If the number of elements is too large, the beam may become too sharp and scanning may take time. Therefore, by adding an operation procedure for increasing or decreasing the number of elements even in the initial stage, more efficient beam capturing can be performed.

Next, FIG. 5 shows a flowchart of still another example of the operation procedure of the antenna of the present invention in the first embodiment. In this operation procedure, the operation procedure up to the first half of completing the beam capture is the same as the operation procedure shown in FIG. That is, the number of antenna elements is gradually increased (S11), the phase amount of the variable phase shifter of the increased antenna elements is changed (S12 to S15), and the received signal level is fixed to the maximum phase amount (S16). ). However, at each stage of this process, the number of antenna elements and the maximum value of the received signal level at that time are stored. In the latter half of the operation procedure, a method of coping with the case where a beam direction shift occurs for some reason after the beam capture is once completed and the communication (reception) state is entered (S17) will be described. First, when in a communication state, the received signal level at that time is grasped (S17, S19) and stored (S1).
8). When it is confirmed that the reception level has dropped or the reception level has dropped below the desired reception level (S19), the operation for recapture is started. At the first stage, the number of antenna elements is gradually reduced, which is completely opposite to the procedure performed in the first beam capturing (S20). Here, the antenna element that was operated at the end of the first beam acquisition is first made inoperative during the re-acquisition. In the process of gradually deactivating the antenna elements, the received signal level is always grasped, stored in the process of the first beam capture, and compared with the maximum received signal level corresponding to the number of antenna elements at each stage. (S21), the number of antenna elements is reduced until these received signal levels become approximately the same (S20). At this stage, the operation procedure in the first half is performed, the number of antenna elements is increased again, the phase amount is controlled, and the gain is increased to perform beam capture. FIG. 6 shows an example of the antenna pattern in this process. In the first acquisition process, as shown in FIG. 6A, the beam of the antenna 1111 → 1112 → 11
13 → 1114, the gain is gradually increased to sharpen the beam and grow the beam. If the arrival direction of the radio wave is deviated, the beam 1114 cannot receive the radio wave. Here, contrary to the growth process, the beam is made to have a low gain, and when the beam width is expanded to the beam 1112, the condition (same received signal level) exactly the same as the first acquisition intermediate process is obtained. . At this stage, the beam is grown again, and as shown in FIG. 6B, the beam has a high gain of 1112 → 1115 → 1116 and can be accurately matched with the arrival direction of the radio wave.

The operation procedure of FIG. 5 is effective when the relative position of the wave source viewed from the antenna changes after capturing the wave source. According to this operation procedure, when the beam is deviated,
There is an advantage that the beam can be captured again in a shorter time than when the beam capturing is restarted from the beginning. Therefore, it is very effective as an antenna for mounting on a mobile body or an antenna for a mobile terminal, which always requires beam tracking of the antenna.

FIG. 7 shows another structure of the antenna of the present invention shown in the first embodiment. The difference from the configuration example shown in FIG. 1 is that the LNAs 1016, 1017, 1018 are connected to the control circuit 1
It is controlled by 013 and its amplification factor can be changed. Since not only the phase of the signal received by each antenna element but also the amplitude can be changed, directivity shaping can be performed in addition to directing the beam toward a desired wave source.
For example, it is effective in an environment where low side lobes are required to reduce interference waves.

FIG. 8 shows another structure of the antenna of the present invention shown in the first embodiment. Although it is almost the same as the configuration example shown in FIG. 7, it is characterized by removing the switch and the non-reflection end here. In the case of this configuration example, by controlling the control signal sent from the control circuit 1020 to the LNAs 1016, 1017, 1018, the LN
In addition to changing the amplification factor of A, it also functions as a switch (O
The FF state is realized by minimizing the amplification factor). Therefore, the structure of the antenna can be greatly simplified while maintaining the same operation and effect as the structure example shown in FIG. FIG. 9 shows another configuration of the antenna of the present invention shown in the first embodiment. Although the receiving antenna has been described in the above embodiments, this embodiment shows a configuration for both transmission and reception. The configuration after the receiving antenna elements 1000, 1001, 1002 is the same as that shown in FIG. In the transmitting antenna, HPA (high-power amplifier) 1024, 1025, 1026 and variable phase shifters 1027, 1028, 1029 are connected to antenna elements 1021, 1022, 1023, respectively. Here, the output signal from the transmitter 1032 is distributed by the distributor 1031 and transmitted to each transmitting antenna element. Here, the radio wave radiated from each transmitting antenna element has a certain phase amount set by the variable phase shifters 1027, 1028, 1029, and forms a pattern in which the beam is directed in a certain direction. The setting of the phase amount of the variable phase shifter of the transmitting antenna is performed by the control signal generated by the control circuit 1031. The control circuit 1031 also commonly controls the receiving antenna, and the phase distribution given to the transmitting antenna can be easily obtained from the information of the phase distribution given to the receiving antenna. For example, if the transmission and reception frequencies are substantially the same and the arrangement of the antenna elements is also the same, the amount of phase given to the transmitting antenna elements may be the same as the amount of phase of the corresponding receiving antenna elements. If the frequencies are different, the phase amount may be converted according to the frequency difference and given to each transmitting antenna element.

With the above-described structure, it is possible to provide an antenna that shares transmission and reception and that can be easily captured with a structure with simple beam pointing. It is very effective for antennas for portable radios and satellite communications.

The same effect as that of FIG. 9 is obtained even when the configuration of FIG. 10 is performed. The characteristic of the configuration of FIG.
By using 36, 1037, and 1038, the antenna elements 1033, 1034, and 1035 are commonly used for transmission and reception. With this configuration, the antenna that effectively performs beam pointing for transmission and reception is extremely small.
It can be made lightweight. Greatly effective as an antenna for portable radios that are often carried.

In addition to the above, the effect of the antenna of the present invention is the same even if the following modifications are made.

In the embodiments described so far, the phase amount is controlled so as to maximize or maximize the received signal level. Here, the received signal level may be signal strength or power value. Further, the maximum value of these values may be obtained by measuring the S / N ratio (reception power to noise power ratio) or the C / N ratio (carrier power to noise power ratio). -In the process of growing the beam of the antenna, an example in which all the antenna elements are finally operated has been described. Instead, desired values of the received signal level and the S / N ratio are set in advance. Even if there is an antenna element that does not operate if the value exceeds this value, the beam capturing may be ended here. In this case, an antenna pattern having a gain higher than necessary to maintain the communication circuit is not formed, and the beam is not sharpened more than necessary.
Therefore, it is possible to prevent the communication from being interrupted as much as possible due to the deviation of the beam direction of the antenna due to the influence of the external environment. Effective for mobile and portable antennas.

In the above embodiments, when the number of antenna elements operating in the process of growing a beam is increased, the phase amount related to the antenna element in the previous stage is fixed and the phase related to the increased antenna element is fixed. Only the amount was controlled. However, in this case, the finally set phase distribution may not be optimal in a strict sense in order to direct the beam in the arrival direction of the radio wave. In such a case, the gain of the antenna is slightly lower than that in the optimum case. As a means for solving such a problem, a procedure of re-adjusting the phase amounts of all the antenna elements operating in the final stage of beam capture can be added to the operating procedure. In this case, since the phase amount of each antenna is close to the optimum value, the range in which the phase amount is changed can be very narrow. Therefore, the antenna pattern can be strictly optimized efficiently in a short time with a simple configuration in which a few steps are added to the operation procedure.

In the above embodiments, the example of controlling the phase amount so as to maximize the desired received signal level has been described. In addition to this, in an environment where there is an interfering wave, it is possible to detect the receiving level of the interfering wave, raise the receiving level of a desired signal, and control the phase amount so as to lower the receiving level of the interfering wave. In this case, the final antenna pattern has a high gain in the desired radio wave direction and a null is formed in the interference wave direction. Such a function is very important for an antenna used in an environment where radio devices will be increasingly used in the future and an extremely large amount of radio waves that interfere will be generated.

In the above-described embodiments, an example in which the circuit of the radio wave reaching the transmitter / receiver is configured by an analog system has been shown. Alternatively, a configuration using a digital circuit as shown in FIG. 11 can be considered. Here, the antenna elements 1201 and 12
02 and 1203 are LNAs 1204, 1205 and 12 respectively.
06, frequency converters 1207, 1208, 1209, A
It is connected to the / D converters 1210, 1211 and 1212, and the received signals are converted into digital signals.
This digital signal is input to a DBF (digital beam forming circuit) 1213. In DBF, CPU12
Based on the control signal from 14, the operation for beam growth in the embodiments described so far is performed. With this configuration, it is possible to obtain exactly the same effect as in the case of the analog system. In addition, the digital signal makes CP
It is easy to control by U, and a variable phase shifter or the like is not necessary for controlling the phase, which is a great effect in terms of antenna configuration and processing.

There are several ways to increase the number of operating antennas. Nine microstrip antenna elements 125 as shown in FIG.
Taking the case of an antenna composed of 1-1259 as an example,
Here are some examples of how to increase it. As a method of moving the antenna elements one by one, for example, the antenna element 1
251 is operated first, then the antenna element 125
2, then antenna element 1254, then antenna element 12
There is a method of increasing the number of antenna elements that operate so as to surround the antenna element that operates first, such as 55. In addition, first, only the antenna element 1251 is operated, and next, the three antenna elements 1252, 1254, and 1 are operated.
There is also a method of operating 255 at the same time and finally operating all the antenna elements. Basically the important thing is
This is to operate so as to gradually widen the effective aperture of the antenna and gradually narrow the beam width. By doing so, it is possible to grow the beam so that the beam surely faces the arrival direction of the radio wave.

An embodiment of the present invention using a reflector antenna will be described below with reference to the drawings.

FIG. 13 is a sectional view of an antenna showing an embodiment of the present invention. This antenna includes a primary radiator 2005 and a reflector 20 through an antenna structure 2006.
This is a reflector antenna configured by fixing 04, and is characterized in that a part of the radio wave reflected by the reflector can be shielded by the shield plate 2001. The shield plate 2001 is made of a material that absorbs radio waves, or is formed so that a radio wave absorber is attached to the surface of the plate to absorb radio waves. In addition, the shielding plate 2001 has a driving unit 2002.
By moving with, the amount of blocking the antenna opening can be changed. The shielding plate 2001 has a structure that can be stored in the cover 2003. The radio wave received by the primary radiator 2005 is connected to the receiver 2009. The signal level received at the receiver is constantly monitored by the CPU 2008. The CPU generates a control signal for moving the antenna, that is, changing the beam direction based on the received signal, and transmits the control signal to the antenna driving unit 2007.
The antenna driving unit 2007 can change the beam direction of the antenna by moving the entire antenna. At the same time, the CPU 2008 also generates a control signal to the drive unit 2002 for moving the shielding plate 2001.
It can be seen that, with the above-described configuration, the CPU 2008 has a function of performing the following.

The shield plate is moved to change the size of the effective aperture of the antenna to change the sharpness of the beam.

The antenna driving unit is moved to change the beam direction of the antenna.

The intensity of the received signal is monitored and stored.

By combining the above functions, the CPU can control the operation of automatically directing the beam in the direction of arrival of the radio wave and sharpening the beam width (that is, increasing the gain). The specific procedure is shown below.

FIGS. 14, 15 and 16 show how the antenna beam is gradually sharpened, the beam is directed in the direction of arrival of the radio wave, and the gain is increased. Here, as the simplest case, when a radio wave arrives from an arbitrary direction in the xz plane shown in FIG. 14, a procedure for directing the beam in that direction will be shown. In each of the drawings, those not related to the description are omitted for simplification so that the relationship between the shield plate and the beam can be understood.

FIG. 14 shows an initial state for capturing the arrival direction of a radio wave. A large part of the reflecting mirror 2004 is shielded by the shielding plate 2001, and the substantial aperture is A in the x direction.
-A 'area. Therefore, the beam in this case has a wide-angle radiation directivity as shown in the figure, and the gain is low. Rough beam capture is performed using this wide-angle beam. Specifically, the beam direction is changed by moving the entire antenna by the antenna driving unit 2007 (in the initial stage, the beam is directed in all directions in which radio waves may arrive). At this time, the receiver 2009 constantly monitors the reception intensity of the radio wave, grasps the beam direction in which the reception intensity of the radio wave is maximum, and finally fixes the beam direction of the antenna in that direction. In the above process, the CPU 2008 performs all the monitoring of the reception intensity at the receiver, the generation of the control signal to the antenna driving unit for driving the shield plate and changing the beam direction. The function of the CPU is the same in the subsequent steps shown in FIGS.

At the initial stage shown in FIG. 14, since the beam width is wide, the beam cannot be accurately directed in the direction of arrival of the radio wave. Further, in this case, the gain is low. Therefore, in the next stage, the beam width is gradually narrowed so that the arrival direction of the radio wave and the beam direction are accurately matched. As a concrete means, the shielding plate 2001 is slightly driven outward to reduce the area for shielding the reflecting mirror and enlarge the substantial opening. In FIG. 15, the area BB ′ is a substantial antenna aperture. As a result, the beam becomes sharp as shown in the figure, and a radiation directivity with high gain is formed. At this stage also, the beam direction is changed by driving the antenna driving unit, and at the same time, the direction of the maximum value of the reception intensity is searched by monitoring the reception signal intensity. Then, the antenna is fixed so that the beam faces the maximum value direction. in this case,
Unlike the initial stage, since the area for searching the maximum value of the intensity of the received radio wave is known to some extent, the narrowing of the beam width does not increase the searching time. The beam direction can be controlled with higher accuracy than in the previous step in a relatively short time.

By repeating the above procedure, the beam width is gradually narrowed and the gain is increased, and finally, as shown in FIG. 16, all the antenna apertures are used.
In this case, the beam width is the narrowest and the gain is also the maximum. The beam direction also accurately matches the arrival direction of the radio wave.

With the configuration of the present invention described above, the following effects can be expected.

Beam pointing of a high gain antenna can be performed accurately, easily and quickly. For example, in the case of an antenna for satellite communication / satellite broadcasting, the beam direction can be matched with the satellite direction very easily when the antenna is first installed. Also,
When using it as a mobile or portable antenna, the location where the antenna is installed is often changed, so in such a case the annoyance of frequent antenna pointing can be eliminated, so it is very effective. Is.

Since it is a method of gradually narrowing the direction of arrival of the radio wave, there is little chance of a pointing error such that the direction of the radio wave coincides with the side lobe direction, and it is practically effective.

The structure of the present invention shown in FIGS. 13 to 16 is as follows.
The same effect can be expected even if the following changes are made.

In this embodiment, the radio wave is shielded between the reflecting mirror and the far field area, but the place where the radio wave is shielded is not limited to this. For example, as shown in FIG.
Even if the radio wave is shielded in the radio wave propagation path between the primary radiator and the reflecting mirror, the same effect can be expected. FIG.
In FIG. 7, a shield plate 2010 shields radio waves, and this shield plate is moved by a drive unit 2011 and can be housed in a cover 2012. With such a configuration, it is possible to reduce the size and weight of the mechanical part that shields radio waves (shielding plate, drive part, cover, etc.). It is convenient when used as a portable antenna. Not limited to this example, the effect of the present invention is the same as long as it has a structure for shielding in the propagation path of the radio wave.

In the embodiment, the antenna aperture is shielded in one direction and the beam scanning is performed in that direction.
Of course, two-dimensional beam scanning is possible. 18 and 19 show a configuration example of the shielding plate in the case of performing two-dimensional beam scanning. In FIG. 18, a shield plate 2020 that changes the horizontally shielded region and a shield plate 2021 that changes the vertically shielded region are separately provided, and each is independently controlled. In this case, the beam direction control can be performed independently in the horizontal and vertical directions such that the beam direction control is first performed in the horizontal plane and then the beam direction control is performed in the vertical plane. Such a configuration is effective when the control is frequently performed on either side and the other direction is known to some extent. For example, when receiving radio waves from a geostationary satellite, the elevation angle (angle from the horizontal plane) looking into the satellite is known to some extent, and antenna beam direction control is important in the horizontal plane. Beam pointing can be done efficiently. In the example shown in FIG. 19, the shielding plate 2022 and its drive unit are provided in the same structure as the diaphragm of the lens of the camera. With such a configuration, the size of the aperture can be gradually changed and the beam width can be changed two-dimensionally. Such a configuration is effective as a means for performing two-dimensional beam pointing.

In the embodiments, the description has been made by taking as an example that the sharpness and the gain of the beam are changed by the structure in which the opening of the reflecting mirror antenna is covered with the shielding plate, but the structure of the present invention is applicable to the antennas of other systems. It can be applied in the same way and the exact same effect can be expected. For example, the surface of the lens antenna or array antenna may be covered.

In the embodiment, the method of moving the entire antenna is used for controlling the beam direction, but a method of changing the beam direction by moving a part of the antenna may be used instead. For example, it is connected to an antenna driving unit so that only the reflecting mirror can be driven, and the beam direction is controlled by driving the reflecting mirror, or the reflecting mirror is composed of two reflecting mirrors such as a Cassegrain antenna. A method of driving the sub-reflector can be used. In such a case, it is only necessary to drive a lighter portion that is smaller than the entire antenna, which is an advantage that the configuration of the antenna drive unit can be simplified.

In the embodiment, the configuration is shown in which only the receiver is connected, but in addition to this, it is possible to connect a transmitter and make it possible to share transmission and reception. In this case, the antenna beam control system does not need to be changed at all, only a transmitter system needs to be added, and the antenna beam for transmission and reception can be accurately aligned with the direction of arrival (radiation) of the radio wave and a high gain antenna can be realized It is effective as a mobile antenna, a satellite communication / satellite broadcast antenna, and the like.

In the embodiment, the case of a fixed reflector antenna having a mirror surface shape has been described, but the present invention can be applied to an antenna whose mirror surface shape can be changed by some method. As an example thereof, an embodiment in the case of a deployable antenna will be described with reference to FIGS. The deployable antenna is a type of antenna that has been proposed as an antenna for mounting on a satellite.It is a small antenna that can be folded or stowed when it is inside the fairing of a launch vehicle, and then unfolded when it is in orbit. is there. As a concrete method,
There are methods such as unfolding like an umbrella, inflating by inserting the gas inside it like a balloon, and unfolding something that is folded by a truss structure (frame structure). In all of these types of deployable antennas, in the process of deploying the antenna, by gradually expanding the portion that operates as a reflector, the reflector antenna shown in the embodiment of the present invention is exactly the same. It can have a function. For example, FIGS. 20 to 22 show cross sections of the deployable truss antenna and show how the antenna is gradually expanded. FIG.
In, the antenna formed by the truss structure body 2025 is partially expanded, and the other antennas are still folded. Radio waves from the primary radiator 2024 are mesh 202
6 (which may be formed of anything that reflects radio waves). In this case, only the portion where the reflecting mirror is formed by the mesh operates as the reflecting mirror, and the beam of the antenna is wide. A driving unit (actuator 2023) for mechanically changing the shape of the truss is provided in the truss structure, and the beam direction can be controlled by driving this and changing the shape of the entire reflecting mirror. Therefore, first, the shape of the reflecting mirror is obtained by moving the actuator in the stage where the beam width is wide so that the beam is roughly directed in the direction of arrival of the radio wave, and the next stage (see FIG. 2).
In 1), a part of the antenna is further developed, and the actuator in that part is operated to further control the beam direction. At this stage, the beam width is narrower than the initial state and the gain is high. Finally, by deploying all the antennas and operating the actuator in the open part, the gain is maximized and the beam directions are matched with the highest precision. Also in this embodiment, the intensity of the received radio wave is constantly monitored by the CPU, and the control signal generated here operates the actuator for expanding and changing the shape of the antenna. Further, in order to change the beam direction here, instead of changing the shape of the reflecting mirror surface, the shape of the entire antenna may be changed. With the above configuration, the beam direction of the deployable antenna can be controlled easily and in a short time. Further, in such a deployable antenna mounted on a satellite, the shape of the antenna may change due to the influence of heat or vibration. However, even if the configuration of the present invention is used, even if the influence of heat or vibration occurs. It is possible to absorb these influences by changing the shape of the antenna with the actuator to find the maximum value of the received radio wave, and it is very effective as a satellite antenna.

In the embodiment, the example has been described in which the CPU controls so that the antenna gain is gradually increased and finally the maximum gain that the antenna can output is obtained. However, in this control, it is possible to stop the beam direction control and stop the gain increase when the level reaches the level required by the antenna reception system (or transmission system). For example, the reception level is monitored by the CPU, and C
The PU determines that the reception intensity, the S / N ratio, etc. have reached the desired level, and at this stage the antenna aperture is widened to narrow the beam width and stop increasing the gain. By doing so, it is possible to prevent the beam from being sharpened more than necessary. In this case, the tolerance of pointing accuracy in the beam direction of the antenna can be maximized, and it is possible to prevent the beam direction from being deviated and the gain being lowered due to the position variation of the antenna or the influence of heat. This is important for practical use, and is particularly effective when it is considered that the pointing may be displaced due to the influence from an external factor such as an antenna mounted on a mobile body.

In the embodiment, an example is shown in which the antenna beam is formed so that the antenna gain is increased monotonically. On the other hand, depending on the situation, a new effect can be expected by adding an operation mode that lowers the antenna gain (widens the beam width). For example, when the state where the beam direction coincides with the arrival direction of the radio wave is deviated due to some factor, the operation in the embodiment shown so far is performed from the beginning in order to capture the beam again. Become. However, in this case, it is possible to efficiently capture the beam by starting from a certain stage where the beam is rather sharp and the gain is high, rather than starting from the initial state at all. Therefore, when the CPU determines that the beam has been deviated (for example, when the reception intensity is low), the antenna opening is gradually narrowed to widen the beam width, and the radio wave arrival direction is captured. (For example, when the reception intensity is memorized in the series of processes for the first beam capture and the beam intensity is at the same level as the beam capture intensity at each stage in the process of expanding the beam width) It can be judged that the direction of arrival of the radio wave has been captured)
From this stage, the beam capturing operation shown in the embodiment is performed. By performing the above control by the CPU, it is possible to efficiently regain the capture of the beam direction when the beam direction is deviated. This is very effective, for example, in an application such as a mobile-mounted antenna, when the arrival direction of radio waves changes momentarily such as during movement.

Next, an example of the present invention using a reflect array will be described.

FIG. 23 shows the external appearance of a portable transmission / reception device using a reflect array. The portable transmission / reception device can be stored in a box shape, and a lid 2031 having a reflect array is formed.
It can be operated as a transceiver by opening and fixing. Taking the case of reception as an example, the radio wave is reflected by the reflect array, the phase distribution of the reflected wave changes at this time, and the received radio wave is concentrated on the primary radiator 2032. The primary radiator 2032 is connected to the transceiver 2033 and functions as a transceiver. Such a transmitting / receiving device is portable and can be carried around freely. FIG. 24 shows a block diagram of this transmitting / receiving apparatus. The transceiver 2033 grasps the reception intensity level, and the CPU 2035 monitors this level. The CPU 2035 generates a control signal, transmits it to the reflect array 2036, and changes the phase distribution of the radio wave reflected by the reflect array based on this control signal. The beam direction changes due to the change in the phase distribution. FIG. 2 shows a specific configuration example of the reflect array 2036.
5 shows. The reflect array is a dielectric substrate having a ground conductor formed on one side or a substrate 2 made of a honeycomb structure.
On the upper surface of 041, patch antennas 2042 to 2054,
A microstrip line 2056 and a module 2055 connected to each patch antenna, a microstrip line connected to each module, one of which is open or short-circuited, and one of which is terminated by a resistor 2058. It Here, it is assumed that each module performs the following two operations based on a control signal issued from the CPU.

The patch antenna is connected to the line side connected to the resistor. In this case, the electric wave received by the patch antenna is absorbed by the resistor, and the electric wave is not re-emitted from the patch antenna. Therefore, the patch antenna portion having such an operation does not operate like a reflector.

The patch antenna is connected to the line side where one side is short-circuited or open. In this case, since the radio wave received by the patch antenna is totally reflected at the terminal, the radio wave is re-radiated from the patch antenna. At this time, it has means for varying the phase of the re-radiated radio wave. The patch antenna portion of such operation operates like a reflector, and the phase distribution changes according to the phase amount set by the means for changing the phase. By controlling this phase distribution by the control signal from the CPU, it becomes possible to freely control the beam direction of the radio wave reflected by the reflect array.

Here, the control signal issued from the CPU is 2
Note that there are different types. One of them is for performing control for switching between two lines, and the other is for setting a phase amount at the time of re-radiation of a received radio wave to a predetermined value. 26 and 27 show specific configuration examples of the module. In the example of FIG. 26, the antenna 2060 is connected to the switch 2061 formed in the module 2055. The switch 2061 connects the line to the resistor 20.
The line 2057 side to which 58 is connected or the line 2056 side whose terminal is short-circuited or opened is selected. Resistor 2
When 058 is selected to the connected line 2057 side, the electric wave received by the antenna is absorbed by the resistor 2058 (the characteristic impedance of the line and the resistance value of the resistor are made the same), so Radio waves are never re-emitted. When the terminal is selected on the side of the line 2056 where the terminal is short-circuited or opened, the radio wave is completely reflected at the terminal and re-radiated. At this time, the phase shifter 2062 is formed as a means for changing the phase on the way of the radio wave. By adjusting the phase amount of the phase shifter, the phase amount of the re-radiated radio wave can be freely set. In addition to this, a configuration as shown in FIG. 27 is also conceivable. The difference from FIG. 26 is that an amplifier is provided in the path of the radio wave when reradiating the radio wave. The amplifier is
Amplifier 2065 for reception path and amplifier 20 for transmission path
There are two of 66, and circulators 2063, 2064
Each route is selected by. That is, the radio wave received by the antenna flows to the receiving amplifier 2065 side by the circulator 2063 and is amplified. This radio wave is input to the phase shifter 2062 by the circulator 2064 and a predetermined phase amount is set. This radio wave is totally reflected by the end of the line 2056 and propagates in the reverse direction on the line. Here, the phase amount is changed again by the phase shifter 2062, and this time by the circulator 2064, an amplifier 2066 for transmission.
Radio waves flow in the direction of. The radio wave amplified by the amplifier 2066 propagates toward the antenna 2060 by the circulator 2063 and is re-radiated from the antenna. The characteristic of FIG. 27 is that the radio wave is amplified in the process of re-radiation of the radio wave, which is effective in compensating for power loss in the middle of this path and preventing deterioration of noise characteristics. . With the above configuration, a module used for the reflect array can be realized. This module is MMI
It is possible to reduce the size by C (monolithic microwave integrated circuit) technology, and it is effective in reducing the thickness and size of the entire reflectarray.

Now, with the above configuration, by any method, the beam can be accurately directed in the arrival direction of the radio wave,
Explain how to increase the gain. This method is
It relates to what kind of control signal is generated by the PU. The following is a description of each step that elapses with time.

Step 1: Only the patch antenna 2048 shown in FIG. 25 is used as the antenna for re-radiating the reflected radio wave, and the CPU generates and transmits the control signal so that there is no re-radiation from the other patch antennas. Specifically, only the switch in each module corresponding to the patch antenna 2048 is selected as a path for reradiating radio waves.
The antenna pattern at this time has wide-angle directivity like the beam 1 shown in FIG. Further, the CPU monitors and stores the intensity of the received radio wave in this case.

Step 2: Next, the patch antenna 204
Patch antennas 2045, 2046, 2 around 8
050 and 2051 are controlled by a control signal so as to re-radiate the reflected radio waves similarly to the patch antenna 2048.
In this case, a beam having a sharper and higher gain than the beam 1 can be formed like the beam 2 shown in FIG. Further, the beam direction can be changed by controlling the means for changing the phase in each module. Therefore, for example, the phase amount of the phase shifter in each module is sequentially changed, and the beam is scanned within a certain range. The intensity of the received radio wave is monitored in each beam direction, the beam direction in which the received intensity is maximized is searched for, and the phase amount of each phase shifter is fixed so that the beam is finally directed in that direction. In this case, considering the phase amount of the radio wave re-radiated by the patch antenna 2048 as the reference phase, it is not necessary to change this phase amount. In other words, patch antenna 2
Regarding 048, it is not necessary to provide a phase shifter. Therefore,
It is only necessary to control the amount of phase for the four surrounding antennas.

Step 3: As a final step, all patch antennas are controlled by a control signal so that the reflected radio waves are re-radiated. At this time, the antenna pattern has the narrowest beam width and the highest gain as the beam 3 in FIG. Similar to step 3, by controlling the means for changing the phase in each module, the beam direction is changed, the beam is scanned within a certain range, and the intensity of the received radio wave is monitored in this to obtain the received intensity. Finds the maximum beam direction and finally directs the beam in that direction. At this time, since the beam direction has been clarified to some extent up to step 2, the beam scanning range can be narrowed. Also, the phase amount in the means for changing the phase of the patch antenna controlled up to step 2 may be fixed, and only the phase amount of the part newly added in this step may be adjusted. Therefore,
It is possible to efficiently control the phase amount and search for the direction of maximum reception intensity in a short time.

With the above configuration, the following effects can be expected.

Beam pointing can be performed accurately, easily and quickly in a high gain antenna. In particular, since beam scanning and beam exploration can be performed completely electronically, these operations can be performed at extremely high speed. In addition, it is effective for use as a mobile or portable antenna, and the annoyance of frequent antenna pointing can be eliminated when the place where the antenna is installed is often changed.

Since this is a method of gradually narrowing the direction of arrival of the radio wave, it is practically effective since there are few pointing errors that would cause the direction of the radio wave to coincide with the side lobe direction. Further, here, instead of controlling the phase amounts of all the re-radiating antennas at the same time to search the beam direction, the antennas that are sequentially operated are expanded and controlled, so control and beam searching are very efficient and It can be done in a short time.

The electronic control is performed by the CPU, and a new function can be added with a simple modification by changing the control algorithm. For example, as shown in the example using the reflector antenna, the antenna gain can be kept to the minimum required level, and a mode for reducing the gain when re-acquiring the beam is added. Easy to change. Naturally, the same effect as that case can be expected.

In the embodiment, the example in which the re-radiating antennas are gradually expanded from the center to the outer side is shown, but the method of increasing the re-radiating antennas is not limited to this. For example, a method of gradually expanding from the antenna at the end may be used, or a method of increasing the operating area for each row may be used. The important point here is that the aperture of the antenna should be expanded so that the number of operating antennas can be increased (selection method) so that the beam width of the antenna can be gradually narrowed and the gain can be increased. Is to choose.

An embodiment of the present invention in which a waveguide or a radial waveguide is used as a power supply circuit will be described below with reference to the drawings.

FIG. 29 is a sectional view of an antenna showing an embodiment of the present invention. Here, the waveguide or radial waveguide 3
001 is composed of upper and lower ground conductors 3002 and 3003, and performs distribution, combination and transmission of radio waves. The waveguide or radial waveguide 3001 is a conductor pin 300.
The conversion of the radio wave by 4 is performed. Conductor pin 3004
Are sequentially connected to the variable phase shifter 3009, the amplifier 3008, and the RF switch 3007, and the antenna element 3 is provided at the final end.
006 is connected. Here, the variable phase shifter 3009,
The amplifier 3008 and the RF switch 3007 are MMIC,
It can be modularized by MIC. RF
The switch 3007 selects whether to operate or not operate the antenna element, and when receiving during operation, the radio wave incident from the antenna element 3006 is amplified by the amplifier 3008, and an appropriate amount of phase is set by the variable phase shifter 3009. Can be set. This radio wave is transmitted to the waveguide or radial waveguide 3001 and the contribution from the antenna element that operates is combined. In the case of transmission, the basic operation is the same except that radio waves are transmitted in the opposite direction. With such a configuration, it is possible to arbitrarily operate only some of the antenna elements of the plurality of antennas and set a desired phase (and in some cases, amplitude) to the radio waves transmitted and received. By using this configuration, as shown in the first embodiment, it is possible to gradually sharpen the beam of the antenna, increase the gain, and finally direct the beam of the desired gain in the arrival direction of the radio wave. Becomes Regarding the operation procedure, all the methods shown in the first embodiment can be applied in this case as well, and the effect is the same. Figure 2
Other effects of the configuration such as 9 are:
The loss of the power supply circuit can be reduced. Compared with microstrip lines, the waveguide line has less loss, and the advantage is that it is possible to realize a power supply circuit including a combiner easily and with low loss. It is very effective as an antenna for space.

When the waveguide and the radial waveguide are used, the effective aperture diameter at which the antenna operates can be changed by devising the feeding circuit. FIG.
0 shows a cross-sectional view of the antenna feeding system in that case. 30 (a), as in FIG. 29, a waveguide or radial waveguide 3100 is formed by a ground conductor 3101,
A slot 3301 is formed in the ground conductor above it. In such a configuration, the electric wave propagating through the waveguide is coupled to the slot, and the electric wave can be transmitted and received. In order to change the range of slots operated here, the range of operation of the waveguide or radial waveguide can be changed by a mechanical method. As a method, a conductor plate or a radio wave absorber 3150 is moved by a driving device (motor) 3500 as shown in the figure. Here, the driving device and the conductor plate or the electromagnetic wave absorber are connected by a transmission device 3151. FIG. 30B shows another method as a method of changing the operating range of the waveguide or the radial waveguide by a mechanical method. here,
A conductor plate or a radio wave absorber 3150 installed below the waveguide or the radial waveguide is projected into the waveguide or the radial waveguide by a driving device 3500. Such a structure has a structure in which the conductor pin 31 is provided for coupling the antenna element and the feeding waveguide as shown in FIG.
Effective when using 03. In the configuration example of FIG. 30B, the helical antenna 33 is used as the antenna element.
However, other types of antenna elements such as a microstrip antenna and a crossed dipole antenna can be used. With the above configuration, the size of the effective aperture of the antenna can be controlled to change the beam width and gain of the antenna. In this configuration, the antenna driving device 3 as shown in FIG.
By providing 600 to allow the entire antenna to be driven so that the beam direction can be changed, the beam can be gradually grown in the arrival direction of the radio wave. The operation procedure can be the same as the method shown in the embodiment of the present invention when the reflector antenna is used, and the effect is the same.

[0094]

With the above structure, beam pointing of a high gain antenna can be realized by a simple structure and control method, and it is also effective for cost reduction of the antenna. This is because the antenna installation and beam tracking procedures are greatly simplified for portable antennas that frequently change the location where the antenna is used and mobile antennas that require beam tracking, and beam pointing is easy. It is effective because it can be done in a short time. Further, since the beam is captured while the beam width of the antenna is gradually narrowed, there is an advantage that operation mistakes such as directing the beam in the wrong direction are reduced.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of an antenna of the present invention.

FIG. 2 is a diagram showing an example of an operation procedure in the first embodiment of the antenna of the present invention.

FIG. 3 is a diagram showing how the antenna pattern changes in the first embodiment of the antenna of the present invention.

FIG. 4 is a diagram showing another example of the operation procedure in the first embodiment of the antenna of the present invention.

FIG. 5 is a diagram showing another example of the operation procedure in the first embodiment of the antenna of the present invention.

FIG. 6 is a diagram showing changes in the antenna pattern in another example of the operation procedure in the first embodiment of the antenna of the present invention.

FIG. 7 is a diagram showing another configuration example in the first embodiment of the antenna of the present invention.

FIG. 8 is a diagram showing another configuration example in the first embodiment of the antenna of the present invention.

FIG. 9 is a diagram showing another configuration example of the first embodiment of the antenna of the present invention.

FIG. 10 is a diagram showing another configuration example of the first embodiment of the antenna of the present invention.

FIG. 11 is a diagram showing another configuration example in the first embodiment of the antenna of the present invention.

FIG. 12 is a diagram showing an example of a method of selecting an antenna element to be operated in the first embodiment of the antenna of the present invention.

FIG. 13 is a sectional view of a reflector antenna showing another embodiment of the antenna of the present invention.

FIG. 14 is a diagram showing an antenna pattern in another embodiment of the antenna of the present invention.

FIG. 15 is a diagram showing an antenna pattern in another embodiment of the antenna of the present invention.

FIG. 16 is a diagram showing an antenna pattern in another embodiment of the antenna of the present invention.

FIG. 17 is a diagram showing another example of a reflector antenna in another embodiment of the antenna of the present invention.

FIG. 18 is a diagram showing a method of shielding an opening of a reflector antenna in another embodiment of the antenna of the present invention.

FIG. 19 is a diagram showing a method of shielding an opening of a reflector antenna in another embodiment of the antenna of the present invention.

FIG. 20 is a diagram showing the configuration and operation of a deployable reflector antenna in another embodiment of the antenna of the present invention.

FIG. 21 is a diagram showing the configuration and operation of a deployable reflector antenna in another embodiment of the antenna of the present invention.

FIG. 22 is a diagram showing a configuration and an operation state of a deployable reflector antenna in another embodiment of the antenna of the present invention.

FIG. 23 is an external view of an antenna using a reflectarray showing another embodiment of the antenna of the present invention.

FIG. 24 is an external view of an antenna using a reflect array showing another embodiment of the antenna of the present invention.

FIG. 25 is a diagram showing a configuration of a reflect array in an antenna using a reflect array showing another embodiment of the antenna of the present invention.

FIG. 26 is a diagram showing a configuration of a reflect array in an antenna using a reflect array showing another embodiment of the antenna of the present invention.

FIG. 27 is a diagram showing a configuration of a reflect array in an antenna using a reflect array showing another embodiment of the antenna of the present invention.

FIG. 28 is a diagram showing how an antenna pattern changes in an antenna using a reflectarray showing another embodiment of the antenna of the present invention.

FIG. 29 is a sectional view of an antenna using a waveguide or a radial waveguide showing another embodiment of the antenna of the present invention.

30A and 30B are a sectional view and an external configuration view of an antenna using a waveguide or a radial waveguide showing another embodiment of the antenna of the present invention.

[Explanation of symbols]

1000,1001,1002,1021,1022
1023, 1033, 1034, 1035, 1201,
1202, 1203, 2060, 3006 Antenna element 1003, 1004, 1005, 1204, 1205
1206, 2065, 3008 LNA 1006, 1007, 1008, 1027, 1028,
1029,2062,3009 Variable phase shifter 1009,1010,1011,2061,3007
Switch 1012 Combiner 1013, 1020, 1030 Control circuit 1014, 2009 Receiver (receiver) 1015, 2008, 2035 CPU 1039 Non-reflective termination 1024, 1025, 1026, 2066 HPA 1031 Distributor 1032 Transmitter 1036, 1037, 1038 min. Wave filters 1207, 1208, 1209 Frequency converters 1210, 1211, 1212 A / D converters 2001, 2010, 2020, 2021, 2022
Shielding plate 2002, 2011, 3500 Driving unit 2003, 2012 Cover 2004 Reflecting mirror 2005, 2024, 2032 Primary radiator 2007, 3600 Antenna driving unit 2023 Actuator 2025 Truss structure 2026 Mesh 2033 Transceiver 2031 Lid 2036 Reflect array 2042, 2043 2044, 2045, 2046
2047, 2048, 2049, 2050, 2051,
2052, 2053, 2054 Patch antenna 2055, 3005 Module 2063 Circulator 3004, 3103 Conductor pin 3001, 3100 Waveguide or radial waveguide 3002, 3003, 3101 Ground conductor 3150 Radio wave absorber or short-circuit plate 3151 Transmission device 3301 Slot 3302 Helical antenna

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Osamu Shibata 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Toshiba Research & Development Center (72) Inventor Hiroyasu Uchida Komukai-Toshiba, Kawasaki-shi, Kanagawa 1 Incorporated Toshiba Research and Development Center

Claims (6)

[Claims] 1. An antenna comprising means for changing radiation directivity so as to gradually increase directivity gain stepwise or continuously. 2. A plurality of antenna elements are provided as means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, and the antenna elements combine or distribute radio waves. Is connected to the antenna element and the power feeding circuit, and a switch and a variable phase shifter for transmitting and blocking a radio wave between the antenna element and the power feeding circuit are provided.
The antenna according to claim 1, which is controlled by a PU. 3. A plurality of antenna elements are provided as means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, and radio waves are combined or distributed to the antenna elements. And a variable amplifier and a variable phase shifter are provided between the antenna element and the power feeding circuit, and the variable amplifier and the variable phase shifter are controlled by a CPU. 1. The antenna according to 1. 4. A shield plate for shielding part of radio waves reflected by a reflector in a reflector antenna as a means for changing radiation directivity so as to gradually increase the directivity gain stepwise or continuously. The shield plate has a structure capable of changing a region for blocking radio waves by a drive unit, and has an antenna drive unit for driving the entire antenna or a part of a mirror surface system, and the drive unit and the antenna drive unit. 2. The antenna according to claim 1, wherein is controlled by a CPU. 5. An antenna using a reflect array as a means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, wherein the reflect array faces the primary radiator. Placed,
A plurality of antenna elements, a switch and a variable phase shifter respectively connected to the antenna element, the CPU controls the switch and the variable phase shifter,
When the switch is OFF, the antenna element is connected to the non-reflection terminal side, and when the switch is ON, the antenna element is connected to the line side where the variable phase shifter is connected and the terminal is opened or shorted. The antenna according to claim 1, wherein: 6. In an array antenna composed of a plurality of antenna elements, as a means for changing the radiation directivity so as to gradually increase the directivity gain stepwise or continuously, the synthesis and distribution of each antenna element is performed. Has a power supply circuit for performing the above, and the power supply circuit is formed by using a waveguide or a radial waveguide, and a radio wave absorber or a short-circuit plate is inserted inside the waveguide or the radial waveguide, or the position is changed. The antenna according to claim 1, further comprising a driving unit for driving the antenna, and an antenna driving unit for driving the entire antenna.