JP2015039218A - Polarization angle division diversity radio transmitter, radio receiver, and radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To implement high-reliability radio communications with a small transmit antenna or receive antenna under the environment where interference is generated by multiple waves (multi-path).SOLUTION: A radio transmitter (10) comprises a modulator (13) which modulates an information signal of a frequency f1 with a carrier wave of a frequency f2 and outputs a first modulation signal. The first modulation signal is transmitted by a transmit antenna (20) of linear polarization, an angle of a linearly polarized wave to be transmitted is rotated in a frequency f3 by a motor (14) that rotates the transmit antenna (20) in the frequency f3, and the first modulation signal is superimposed on independent two vertical polarization and horizontal polarization components. A radio receiver (30) comprises: a diversity receive antenna (31) in which a plurality of input signals are obtained by receiving them on a plurality of polarization planes, respectively; a path difference phase shifter (32) for correcting a phase caused by a path difference of the input signals; and a synthesizer (33) for synthesizing a corrected reception signal.

Description

  The present invention relates to a polarization angle division diversity wireless transmitter, a wireless receiver, and a wireless communication system that realize highly reliable wireless communication.

  In recent years, wireless communication technology has made remarkable progress in the broadcasting and communication fields, and has overcome problems related to reliability, such as a disconnection peculiar to wireless communication. As a result, wireless communication technology is increasingly applied to the control field and the measurement field, which require higher reliability than the broadcasting field and the communication field.

  In particular, in the control field and the measurement field, equipment that builds social infrastructure (hereinafter referred to as “social infrastructure equipment”) has higher communication quality and higher communication quality than general consumer equipment in the broadcasting and communication fields. High reliability, that is, long life of the equipment is particularly required. The social infrastructure device is, for example, an elevator system shown in FIG. 14 or a substation monitoring system shown in FIG.

  Social infrastructure equipment is overwhelmingly larger in size than ordinary consumer equipment and is made of a solid metal member. This social infrastructure device itself becomes an electromagnetic wave scattering source. Therefore, wireless communication in social infrastructure equipment is often performed in an environment where multiple waves (multipath) generated by scattering interfere with each other. For this reason, it is desired to realize highly reliable wireless communication in an environment where interference due to multiple waves (multipath) occurs.

  When the difference in the distance from the transmission point to the reception point is an odd multiple of a half wavelength, the electromagnetic wave energy is canceled out by the interference of the multiple electromagnetic waves and becomes zero, and communication becomes impossible. Conventionally, this problem has been addressed by a spatial diversity technique in which a plurality of antennas are spatially separated by half a wavelength. Spatial diversity technology is based on the fact that even if the electromagnetic wave energy received by one antenna becomes zero due to interference, the electromagnetic wave energy received by other antennas located half a wavelength apart is strengthened by interference. It is a technology that enables reception with an antenna.

  In social infrastructure equipment, electromagnetic waves generated by a wireless transmitter are reflected by the social infrastructure equipment itself to become multiple waves (multipath) and may arrive at the receiver from all directions. Therefore, when the space diversity technique is applied, many antennas are required. For example, it is necessary to prepare a plurality of arrayed antennas even if it is limited when multiple waves (multipath) come in the plane direction. Since the distance between adjacent antennas is a half wavelength of the received electromagnetic wave, there is a possibility that it exceeds the size that can be installed in this social infrastructure device.

  The summary of Patent Document 1 (Japanese Patent Laid-Open No. 10-135919) and FIG. 3 disclose a technique for rotating the polarization plane of a radio wave in order to suppress the effects of fading and noise in wireless communication. Further, paragraph 0006 of the specification of Patent Document 1 states, “On the transmitting side, two pairs of dipole antennas that are crossed at right angles and rotated at right angles to the transmission direction for rotating and transmitting the polarization plane of the radio wave, and this Comprising at least a transmitter having two sets of balanced modulated wave outputs for exciting the signal and comprising a receiver for detecting and receiving rotation of the polarization plane of the incoming radio wave on the receiving side. ing.

  In Patent Document 2 (Japanese Patent Laid-Open No. 2-291731), on page 184, from the upper right 13th line to the lower left 2nd line, in order to remove the influence of fading in wireless communication and to enable transmission and reception of high quality signals. A technique for rotating the polarization plane of a radio wave is disclosed. In the application example 6 described in the upper left 13th line to the upper right 12th line of page 192 of Patent Document 2, the rotation frequency of the polarization plane is added / subtracted to / from the carrier frequency, so that it is long with a small (short) antenna. Techniques for transmitting wavelengths are disclosed.

Japanese Patent Laid-Open No. 10-135919 JP-A-2-291731

  The invention of Patent Document 1 is effective in removing the effects of fading and noise that occur during transmission and reception of radio waves. However, the present invention describes nothing about realizing highly reliable wireless communication in an environment where interference due to multiple waves (multipath) occurs, and reducing the size of the transmitting antenna and the receiving antenna. Absent.

  The invention of Patent Document 2 is effective in removing the influence of fading in wireless communication and transmitting and receiving high-quality signals, and reducing the size of the transmission antenna and the reception antenna. However, this invention does not describe anything about realizing highly reliable wireless communication in an environment where interference due to multiple waves (multipath) occurs.

  Therefore, the present invention provides a polarization angle division diversity wireless transmitter and a wireless receiver that realize high-reliability wireless communication with a small transmitting antenna or receiving antenna in an environment where interference due to multiple waves (multipath) occurs. It is an object to provide a wireless communication system.

In order to solve the above problems and achieve the object of the present invention, the present invention is configured as follows.
That is, the polarization angle division diversity wireless transmitter of the present invention modulates the information signal of the first frequency with the second frequency, and outputs the first modulation signal, the first modulation means, And an electromagnetic wave transmission means for transmitting the modulated signal with two independent polarizations and superimposing a third frequency on the polarization.
Other means will be described in the embodiment for carrying out the invention.

  Advantageous Effects of Invention According to the present invention, a polarization angle division diversity wireless transmitter and a wireless reception that realize highly reliable wireless communication with a small transmission antenna or reception antenna in an environment where interference due to multiple waves (multipath) occurs. And wireless communication systems can be provided.

1 is a schematic configuration diagram showing a wireless communication system according to a first embodiment. It is a figure which shows the multipath in a radio | wireless communications system. It is a figure which shows operation | movement of the radio | wireless communications system which concerns on 1st Embodiment. It is a schematic block diagram which shows the radio | wireless communications system which concerns on 2nd Embodiment. It is a schematic block diagram which shows the radio | wireless communications system which concerns on 3rd Embodiment. It is a figure which shows operation | movement of the radio | wireless communications system which concerns on 3rd Embodiment. It is a schematic block diagram which shows the radio | wireless communications system which concerns on 4th Embodiment. It is a schematic block diagram which shows the radio | wireless communications system which concerns on 5th Embodiment. It is a figure which shows operation | movement of the radio | wireless communications system which concerns on 5th Embodiment. It is a figure which shows the concept of the delay synthetic | combination circuit based on 6th Embodiment. FIG. 10 is a schematic configuration diagram illustrating a delay synthesis circuit according to a sixth embodiment. It is a figure which shows operation | movement of the radio | wireless communications system which concerns on 6th Embodiment. FIG. 10 is a schematic configuration diagram illustrating a delay synthesis circuit according to a seventh embodiment. It is a schematic block diagram which shows the elevator system which concerns on 8th Embodiment. It is a schematic block diagram which shows the substation equipment monitoring system which concerns on 9th Embodiment.

  Hereinafter, a mode for carrying out the present invention (referred to as “the present embodiment”) will be described in detail with reference to the drawings.

≪About the polarization of electromagnetic waves≫
In an embodiment of the present invention, a polarization angle division diversity radio transmitter, a radio that realizes highly reliable radio communication with a small transmission antenna or reception antenna in an environment where interference due to multiple waves (multipath) occurs In order to provide a receiver and a wireless communication system, the polarization of electromagnetic waves is used.

FIG. 2 is a diagram illustrating multipath in a wireless communication system.
This wireless communication system includes a wireless transmitter 10 and a wireless receiver 30. Two independent linearly polarized waves orthogonal to the radio transmitter 10 are transmitted. A path from the wireless transmitter 10 to the wireless receiver 30 is blocked by the electromagnetic wave reflector 300-1. However, the electromagnetic wave transmitted from the wireless transmitter 10 is reflected by the electromagnetic wave reflector 300-2 and reaches the wireless receiver 30. When this electromagnetic wave is reflected by the electromagnetic wave reflector 300-2, it passes through the path length Lr. Therefore, the electromagnetic wave is expressed by the following formula 1 as compared with the shortest path length Ld from the radio transmitter 10 to the radio receiver 30. The phase is shifted by φ.
φ = ((Lr−Ld) ÷ λ) × 2π (Formula 1)
Here, λ is the wavelength of the electromagnetic wave. The wavelength λ of the electromagnetic wave is calculated by Equation 2 below, where c is the speed of light and f is the frequency of the electromagnetic wave.
λ = c ÷ f (Formula 2)

  When the electromagnetic wave is further reflected by the electromagnetic wave reflector 300-2, the plane of polarization undergoes a phase shift by θ. For example, in the reflection of polarized waves perpendicular to the tangent plane of the electromagnetic wave reflector 300-2, the phase shift θ of the polarization plane is 0 degree. In the reflection of the polarized wave parallel to the tangent plane of the electromagnetic wave reflector 300-2, the phase shift θ of the polarization plane is 180 degrees. That is, the phase shift θ of the polarization plane of the reflected wave is generated in each polarized wave of the electromagnetic wave depending on each angle incident on the electromagnetic wave reflector 300-2.

Further, when the electromagnetic wave transmitted from the wireless transmitter 10 is further reflected by another nth electromagnetic wave reflector, a phase shift of φn occurs due to passing through different path lengths Ln. Here, φn is calculated by Equation 3 below.
φn = ((Ln−Ld) ÷ λ) × 2π (Formula 3)
Furthermore, each polarization plane of the electromagnetic wave is reflected with respect to the tangential plane of the nth electromagnetic wave reflector, so that a phase shift θ of the polarization plane of the reflected wave occurs.

  When the electromagnetic wave reflectors reach the wireless receiver 30 via the n paths from the radio transmitter 10 by the n electromagnetic wave reflectors, the polarizations having different phase shifts θn of the polarization planes are detected for each path. To separate. Furthermore, by correcting and synthesizing the phase shift φn for each path, it is possible to avoid the phenomenon that the electromagnetic wave energy becomes zero due to interference of multiple waves (multipath).

  Further, when the polarization of the electromagnetic wave transmitted in this state is rotated, the rotation direction of the polarization due to the reflection of the radio wave by the electromagnetic wave reflector changes, and the path also changes at the same time. At this time, except for special conditions, the plane of polarization of the electromagnetic wave interfering at the reception point varies with time. Since the polarized waves of the electromagnetic waves are transmitted independently, the energy of the electromagnetic waves at this reception point is not zero. Two independent orthogonal polarizations can be transmitted, for example, by two orthogonal vertically polarized antennas. These two antennas do not need to be spatially separated and can be installed with a minimum area. The special condition is a case where the electromagnetic wave energy at the receiving point instantaneously becomes zero when the transmission electromagnetic wave rotates, and the influence on information transmission is so small that it can be ignored.

(Configuration of the first embodiment)
FIGS. 1A and 1B are schematic configuration diagrams illustrating a wireless communication system according to the first embodiment. FIG. 1A shows the configuration of the wireless transmitter 10, and FIG. 1B shows the configuration of the wireless receiver 30.
The wireless communication system according to this embodiment includes a wireless transmitter 10 and a wireless receiver 30.

A wireless transmitter 10 shown in FIG. 1A includes an information generation circuit 11, an oscillator 12, a modulator 13 as a first modulation means, a transmission antenna 20 as an electromagnetic wave transmission means, and a motor as a rotation means. 14.
The output side of the information generation circuit 11 and the output side of the oscillator 12 are connected to the modulator 13. The output side of the modulator 13 is connected to the transmission antenna 20.
The information generation circuit 11 has a function of outputting an information signal in the frequency band f1 that is the first frequency to the modulator 13.
The oscillator 12 has a function of outputting the carrier wave f2 having the second frequency to the modulator 13.
The modulator 13 has a function of modulating the information signal in the frequency band f1 with the carrier wave f2 and outputting it to the transmission antenna 20 as a first modulated signal.

  The transmission antenna 20 has a function of transmitting linearly polarized waves. The motor 14 has a function of rotating the transmission antenna 20 at a (1 / f3) period, that is, at a frequency f3.

  The radio receiver 30 shown in FIG. 1B includes a diversity receiving antenna 31 including a plurality of receiving antennas 31-1 to 31-6, and a path difference phase shifter 32 (= 32-1) serving as a plurality of signal correcting means. 32-6) and a synthesizer 33 which is a synthesizer.

The receiving antennas 31-1 to 31-6 are each arranged on a rotation target with an angle of 60 degrees, and have a function of receiving linearly polarized waves each having an angle of 60 degrees. The receiving antennas 31-1 to 31-6 are connected to the path difference phase shifters 32-1 to 32-6, respectively.
The outputs of the path difference phase shifter 32 (= 32-1 to 32-6) are all connected to the synthesizer 33.

  Each of the reception antennas 31-1 to 31-6 has a function of receiving linearly polarized waves having a predetermined angle. The path difference phase shifter 32 (= 32-1 to 32-6) has a function of correcting and outputting a phase shift based on the path difference of the input signal. The synthesizer 33 has a function of synthesizing and outputting all input signals. In the present embodiment, the phase shifts φ1 to φn due to the path difference of electromagnetic waves indicate the phase shift at the frequency f2.

(Operation of the first embodiment)
3A to 3C are diagrams illustrating the operation of the wireless communication system according to the first embodiment.
FIG. 3A is a diagram illustrating a time change on the y-axis of the electromagnetic wave transmitted from the transmission antenna 20 (FIG. 1). The horizontal axis represents time t, and the vertical axis represents y-axis coordinates. The electromagnetic wave transmitted from the transmission antenna 20 vibrates at a (1 / f2) period by the carrier wave f2. Further, since the transmitting antenna 20 is rotated at the frequency f3 by the motor 14, the plane of polarization of the electromagnetic wave transmitted from the transmitting antenna 20 rotates at a period of (1 / f3).

  The frequency f1 that is the first frequency is set lower than the frequency f2 of the carrier wave that is the second frequency and the frequency f3 that is the third frequency. The frequency f2 of the carrier wave is set higher than the frequency f3.

  FIG. 3B is a diagram illustrating an operation in which the transmission antenna 20 rotates on the xy plane at the frequency f3. The transmission antenna 20 rotates clockwise on the xy plane at the frequency f3. By this rotation, the polarization plane of the electromagnetic wave rotates at the frequency f3.

  FIG. 3C is a three-dimensional view showing a time change on the xy plane of the electromagnetic wave transmitted by the transmitting antenna 20. The coordinates of the x-axis, y-axis, and t-axis are each shown in three dimensions, and the rotation direction of the antenna shown in FIG. 3B is drawn on the xy plane with dotted arrows. The plane of polarization of the electromagnetic wave is indicated by a waveform having a frequency f2. Since the polarization plane indicated by the waveform of the frequency f2 rotates on the xy plane at the frequency f3, the temporal change of the envelope is spiral in the xyt space.

  When the electromagnetic wave radiated from the wireless transmitter 10 reaches the wireless receiver 30 and is reflected by an electromagnetic wave reflector (not shown), the plane of polarization of the electromagnetic wave rotates according to the incident angle with respect to the electromagnetic wave reflector. Accordingly, when there are a plurality of electromagnetic wave reflectors in the space where the wireless transmitter 10 and the wireless receiver 30 are installed, a plurality of electromagnetic waves having different paths and different polarization planes are received. The polarization planes of the plurality of electromagnetic waves change with time at the frequency f3.

  It is assumed that at a certain moment, two reflected waves (electromagnetic waves) having a path difference of half the wavelength arrive at the single receiving antenna 31-1, cause interference, and the phenomenon that the electromagnetic wave energy becomes zero occurs. To do. However, the receiving antennas 31-2 to 31-6 are installed at rotationally symmetrical angles with the receiving antenna 31-1. Any of the electromagnetic waves arriving at the receiving antennas 31-2 to 31-6 arrives from other paths, and therefore does not cause radio wave interference and the phenomenon that the electromagnetic wave energy becomes zero does not occur.

  Further, since the plane of polarization of the electromagnetic wave transmitted by the wireless transmitter 10 is rotating, even if interference occurs at the receiving antenna 31-1, the path of the electromagnetic wave arriving at the receiving antenna 31-1 at the next moment is Change, and therefore no longer cause radio interference.

  The radio receiver 30 of the present embodiment receives electromagnetic waves arriving at a plurality of different polarization angles by a diversity receiving antenna 31 that receives a plurality of different polarizations. Even if a phenomenon occurs in which the reception antenna 31-1 causes radio wave interference and the electromagnetic wave energy becomes zero at a certain moment, any of the other reception antennas 31-2 to 31-6 does not cause radio wave interference. There are many.

  Electromagnetic waves arriving at different polarization planes are respectively received by the plurality of receiving antennas 31-1 to 31-6, and the phase shifts φ 1 to φ 6 due to the path differences of the received electromagnetic waves are corrected by the path difference phase shifter 32. By synthesizing these signals by the synthesizer 33, it is possible to improve the reception sensitivity and improve the reliability of wireless communication.

  For example, the path difference phase shifter 32-i (i = 1 to 6) delays the input signal by t0− (φi ÷ (2π × f2)) when correcting the phase shift φi in the carrier wave f2. Here, t0 is a constant.

  In the present embodiment, the rotation frequency f3 of the polarization plane of the electromagnetic wave is set larger than the frequency band f1 for transmitting the information signal. The radio receiver 30 processes the synthesized received signal with a resolution of (1 / f3) time to avoid the phenomenon that the electromagnetic wave energy becomes zero due to radio wave interference, and receives the information signal in the frequency band f1 without error. Is possible.

(Effects of the first embodiment)
The first embodiment described above has the following effects (A) to (D).
(A) Since the plane of polarization of the electromagnetic wave transmitted by the wireless transmitter 10 is rotating, even if interference occurs at the receiving antenna 31-1, the path of the electromagnetic wave arriving at the receiving antenna 31-1 at the next moment Changes, so that it does not cause radio interference. Therefore, the phenomenon that the electromagnetic wave energy becomes zero can be avoided.

(B) Even if a phenomenon occurs in which the reception antenna 31-1 causes radio wave interference at a certain moment and the electromagnetic wave energy becomes zero, the polarization plane is different in any of the other reception antennas 31-2 to 31-6. So no radio wave interference. Therefore, the phenomenon that the electromagnetic wave energy becomes zero can be avoided.

(C) Electromagnetic waves arriving at different polarization planes are respectively received by the plurality of receiving antennas 31-1 to 31-6, and the phase shift based on the path difference of the electromagnetic waves received by the respective antennas by the path difference phase shifter 32. By correcting φ1 to φ6 and synthesizing the corrected signal by the synthesizer 33, the reception sensitivity can be improved and the reliability of wireless communication can be improved.

(D) The frequency f3 of rotation of the polarization plane of the electromagnetic wave is made larger than the frequency band f1 for transmitting the information signal. The radio receiver 30 processes the combined received signal with a resolution of (1 / f3) time to avoid the phenomenon that the electromagnetic wave energy becomes zero due to radio wave interference, and the information signal in the frequency band f1 can be transmitted without error. It is possible to receive.

(Configuration of Second Embodiment)
FIGS. 4A and 4B are schematic configuration diagrams showing a wireless communication system according to the second embodiment. Elements common to the elements in FIG. 1 showing the first embodiment are common. The code | symbol is attached | subjected. FIG. 4A shows the configuration of the wireless transmitter 10, and FIG. 4B shows the configuration of the wireless receiver 30a.
The wireless communication system of the present embodiment includes a wireless transmitter 10 and a wireless receiver 30a. The wireless transmitter 10 shown in FIG. 4A has the same configuration as the wireless transmitter 10 shown in FIG. 1A showing the first embodiment. Therefore, the description is omitted.

  The radio receiver 30a illustrated in FIG. 4B is a diversity reception antenna including a plurality of reception antennas 31-1 to 31-6, similarly to the radio receiver 30 illustrated in FIG. 1B illustrating the first embodiment. 31, a path difference phase shifter 32 (= 32-1 to 32-6) as a plurality of signal correcting means, and a combiner 33 as a combining means. The radio receiver 30a further includes a delay unit 34 (= 34-1 to 34-6), a time division switch 37, and a delay unit 35 (= 35-1 to 35-6). The time division switch 37 includes an input side switch 37a and an output side switch 37b, and the combination of the respective connections can be switched.

  The receiving antennas 31-1 to 31-6 of the present embodiment are connected to delay units 34-1 to 34-6 and path difference phase shifters 32-1 to 32-6, respectively, via a time division switch 37. After being connected to the delay units 35-1 to 35-6, all are connected to the synthesizer 33.

(Operation of Second Embodiment)
The radio receiver 30a switches the connection between the reception antennas 31-1 to 31-6 and the delay devices 34-1 to 34-6 at high speed with a period of (1 / f3) by the time division switch 37.

  In the present embodiment, similarly to the first embodiment, the frequency f1 that is the first frequency is set lower than the frequency f2 of the carrier wave that is the second frequency and the frequency f3 that is the third frequency. . The frequency f2 of the carrier wave is set higher than the frequency f3.

  In the first ((1 / f3) ÷ 6) period, the radio receiver 30a connects the receiving antenna 31-1 and the delay device 34-1 by the time division switch 37, and the receiving antenna 31-2. The delay device 34-2 is connected, and the receiving antenna 31-6 and the delay device 34-6 are connected in the same manner.

  In the second ((1 / f3) ÷ 6) period, the radio receiver 30a connects the receiving antenna 31-1 and the delay device 34-2 by the time division switch 37, and the receiving antenna 31-2. The delay unit 34-3 is connected, and the reception antenna 31-6 and the delay unit 34-1 are connected in the same manner.

  In the third period ((1 / f3) ÷ 6), the radio receiver 30a connects the receiving antenna 31-1 and the delay unit 34-3 by the time division switch 37, and the receiving antenna 31-2. The delay unit 34-4 is connected, and the receiving antenna 31-6 and the delay unit 34-2 are connected in the same manner.

  In the fourth period ((1 / f3) ÷ 6), the radio receiver 30a connects the receiving antenna 31-1 and the delay device 34-4 by the time division switch 37, and the receiving antenna 31-2. The delay unit 34-5 is connected, and the receiving antenna 31-6 and the delay unit 34-3 are connected in the same manner.

  In the fifth period ((1 / f3) ÷ 6), the radio receiver 30a connects the receiving antenna 31-1 and the delay device 34-5 by the time division switch 37, and the receiving antenna 31-2. The delay unit 34-6 is connected, and the receiving antenna 31-6 and the delay unit 34-4 are connected in the same manner.

  In the sixth period ((1 / f3) ÷ 6), the radio receiver 30a connects the reception antenna 31-1 and the delay unit 34-6 by the time division switch 37, and the reception antenna 31-2. The delay unit 34-1 is connected, and the receiving antenna 31-6 and the delay unit 34-5 are connected in the same manner.

  This switching is synchronized with the mechanical rotation of the transmitting antenna 20. By this switching, the relative angle between the receiving antennas 31-1 to 31-6 connected to the delay devices 34-1 to 34-6 and the transmitting antenna 20 is always within a predetermined range.

  The radio receiver 30a further delays the input signal by delay amounts T to 6T by delay units 34-1 to 34-6, respectively. Since the input electromagnetic wave rotates in the plane of polarization with a period of (1 / f3), interference due to radio wave scattering occurs with a period of (1 / f3). In order to suppress the interference due to the radio wave scattering, the delay amount T is a value ((1 / f3) ÷ 6) that can sample the (1 / f3) period evenly.

  The path difference phase shifters 32-1 to 32-6 correct phase shifts φ1 to φ6 due to the path difference of the electromagnetic wave in these delay signals. The path difference of the electromagnetic wave is caused by the reflection of the polarized wave, and the polarization of the electromagnetic wave rotates with a period of (1 / f3). Therefore, the phase shift due to the path difference of the electromagnetic wave also has a period of (1 / f3). However, it is possible to suppress radio wave interference with other delayed signals without performing optimal phase shift correction at every moment. Therefore, the correction values of the phase shifts φ1 to φ6 due to the electromagnetic wave path difference may be set to predetermined fixed values with the least interference.

  The delay units 35-1 to 35-6 delay the input signals compensated for the rotation phase by (t1-T) to (t1-6T), respectively. The predetermined time t1 is a constant and may be a value of 6T or more. Thereby, the delay amount of all the delay signals can be made equal to the predetermined time t1.

  The synthesizer 33 adds all the input signals. Thereby, even if radio wave interference occurs in any of the receiving antennas 31-1 to 31-6, it is possible to avoid the phenomenon that the electromagnetic wave energy becomes zero due to the interference.

  Furthermore, since the frequency band f1 of the information signal is a frequency lower than the frequency f3, the synthesized received signal only needs to have a predetermined signal strength in one of the (1 / f3) periods. Therefore, communication errors due to radio wave interference can be avoided.

  Therefore, the radio transmitter 10 and the radio receiver 30a according to the present embodiment are affected by radio wave interference even when the installation environment changes and the path of electromagnetic waves reaching the radio receiver 30a from the radio transmitter 10 changes dynamically. Communication errors can be avoided. Thereby, it is possible to improve the reception sensitivity and improve the reliability of wireless communication.

(Effect of 2nd Embodiment)
The second embodiment described above has the following effects (E) and (F).
(E) The radio transmitter 10 and the radio receiver 30a according to the present embodiment have the radio wave interference even when the installation environment changes and the path of the electromagnetic wave reaching the radio receiver 30a from the radio transmitter 10 changes dynamically. It is possible to avoid communication errors due to. Thereby, it is possible to improve the reception sensitivity and improve the reliability of wireless communication.

(F) The rotation period or half period of the polarization plane of the electromagnetic wave received by the wireless receiver 30a is evenly sampled. Therefore, even if radio wave interference occurs at any timing, radio wave interference does not occur at other delay timings, and a phenomenon that electromagnetic wave energy becomes zero due to interference can be avoided.

≪Advantages of digitization of wireless communication system≫
It is analog nonlinear elements that hinders the longevity of communication equipment. An analog non-linear element is a basic element constituting a wireless communication device, such as an analog mixer, an analog modulator, or an analog frequency synthesizer. Since these analog nonlinear elements handle analog signals, the operating point (operating area) of the semiconductor element needs to be strictly fixed. In a semiconductor element that is the mainstream of analog nonlinear elements, the operating point (operating region) of the semiconductor element fluctuates due to changes in environmental temperature and changes over time. Therefore, it is necessary to readjust the operating point of the semiconductor element, which hinders the extension of the life of the wireless communication device.

  However, with the remarkable speedup of digital elements in recent years, functions such as mixer, modulation, frequency conversion, etc. that have been conventionally performed with analog nonlinear elements can be realized with digital circuits. Therefore, readjustment of the operating point of the semiconductor element is not necessary, which can contribute to the extension of the life of the wireless communication device.

  According to the sampling theorem, in order to realize a function equivalent to an analog circuit in a decimal circuit, it is necessary to digitize an analog signal at a sampling period of at least twice the frequency to be handled and to operate the digital circuit at this sampling period It is. The frequency related to this sampling period is called the Nyquist frequency. In order to operate the digital signal processing stably, it is necessary to sample an analog signal at a sampling period that is four times or more of a desired frequency and process the sampled digital signal by a digital circuit.

Wireless communication devices use electromagnetic waves that propagate in space as communication transmission media. The frequency of electromagnetic waves that can propagate in space is in the range of 300 MHz to 3 GHz. When the frequency of electromagnetic waves is 300 MHz or less, the efficiency of radiating radio waves into the air is significantly reduced. When the frequency of electromagnetic waves is 3 GHz or more, the attenuation of electromagnetic wave energy increases due to scattering phenomenon caused by shielding, reflection, diffraction, etc. when radio waves propagate in the air, and communication over long distances is not possible, only short-distance communication is possible It becomes. Therefore, the frequency handled by the wireless communication device is limited to the range of 300 MHz to 3 GHz. Currently, the operating frequency of general-purpose digital elements has been increased from several hundreds of MHz to several GHz, so it has become possible to introduce digital circuits into wireless communication devices to achieve no adjustment and increase the service life. .
Hereinafter, an example in which an analog signal is converted into a digital signal and processed in the third to seventh embodiments will be described.

(Configuration of Third Embodiment)
FIGS. 5A and 5B are schematic configuration diagrams showing a wireless communication system according to the third embodiment, and elements common to the elements in FIG. 1 showing the first embodiment are common. The code | symbol is attached | subjected.
The wireless communication system of the present embodiment includes a wireless transmitter 10b and a wireless receiver 30b.

  A wireless transmitter 10b shown in FIG. 5A includes an information generation circuit 11 similar to the wireless transmitter 10 of the first embodiment, an oscillator 12, and a modulator 13, and the wireless transmission of the first embodiment. Transmission antennas 20b-1 and 20b-2, which are different from the apparatus 10, further include a baseband circuit 17, an oscillator 16, a phase shift circuit 15 as phase shift means, and a modulator 18 as second modulation means. -1 and a modulator 18-2 which is a third modulation means.

  The output side of the information generation circuit 11 is connected to the baseband circuit 17. The output side of the baseband circuit 17 and the output side of the oscillator 12 are connected to the modulator 13.

  The output side of the modulator 13 is connected to the modulator 18-1 and the modulator 18-2. The output side of the oscillator 16 is further connected to the modulator 18-1. Further, the output side of the oscillator 16 is connected to the modulator 18-2 via the phase shift circuit 15.

The output side of the modulator 18-1 is connected to a transmission antenna 20b-1 that is a first transmission antenna. The output side of the modulator 18-2 is connected to a transmission antenna 20b-2 that is a second transmission antenna.
The baseband circuit 17 has a function of converting the signal output from the information generation circuit 11 into a digital signal.
The oscillator 16 has a function of outputting an oscillation signal having a frequency f3.
The modulators 18-1 and 18-2 have a function of further modulating the signal output from the modulator 13 with the frequency f3.
The phase shift circuit 15 has a function of shifting the phase of the oscillation signal having the frequency f3 by 90 degrees. However, this angle does not have to be exactly 90 degrees, and may be between 85 degrees and 95 degrees. At this time, the maximum value of the noise component of the oscillation signal caused by the angular deviation is COS (85 degrees) = COS (95 degrees) = 8.7%. When the angle is less than 85 degrees or exceeds 95 degrees, the maximum value of the noise component of the oscillation signal caused by the angular deviation is 8.7% or more.
The transmission antenna 20b-1 and the transmission antenna 20b-2 have a function of transmitting linearly polarized waves, and are arranged so as to have an angle of 90 degrees with each other. However, this angle does not have to be exactly 90 degrees, and may be between 85 degrees and 95 degrees. At this time, the maximum value of the noise component of the linearly polarized wave caused by the angular deviation is COS (85 degrees) = COS (95 degrees) = 8.7%. When the angle is less than 85 degrees or exceeds 95 degrees, the maximum value of the noise component of the oscillation signal caused by the angular deviation is 8.7% or more.

  The radio receiver 30b shown in FIG. 5B is a receiving antenna 31b-1, which is a first receiving antenna, a receiving antenna 31b-2, which is a second receiving antenna, and first rotation frequency detection means. A rotation frequency detection circuit 60-1, a rotation frequency detection circuit 60-2 as second rotation frequency detection means, a delay synthesis circuit 40 as delay synthesis means, a digital demodulation circuit 47, and a baseband circuit 48 I have. Furthermore, each of the rotation frequency detection circuits 60-1 and 60-2 includes a rectifier circuit 61, a low-pass filter 62, and an analog / digital converter (hereinafter referred to as “A / D converter”) 63.

The output sides of the receiving antennas 31b-1 and 31b-2 are connected to rotation frequency detection circuits 60-1 and 60-2, respectively. The output sides of the rotation frequency detection circuits 60-1 and 60-2 are connected to the delay synthesis circuit 40. The output side of the delay synthesis circuit 40 is connected to the digital demodulation circuit 47. The output side of the digital demodulation circuit 47 is connected to the baseband circuit 48. The output terminal of the baseband circuit 48 is the output terminal of the wireless receiver 30b.
The receiving antennas 31b-1 and 31b-2 are installed perpendicular to each other and each have a function of receiving linearly polarized waves. However, this angle does not have to be exactly 90 degrees, and may be between 85 degrees and 95 degrees. At this time, the noise component of the received signal due to the angular deviation is COS (85 degrees) = COS (95 degrees) = 8.7% or less. When the angle is less than 85 degrees or exceeds 95 degrees, the maximum value of the noise component of the oscillation signal caused by the angular deviation is 8.7% or more.
When the phase shift amount of the phase shift circuit 15, the installation angles of the transmission antennas 20b-1 and 20b-2, and the installation angles of the reception antennas 31b-1 and 31b-2 are all 85 degrees or 95 degrees think of. At this time, the sum total of the noise components resulting from the angular deviation is 8.7% × 3 = 26.1%. Therefore, the phase shift amount of the phase shift circuit 15, the installation angle of the transmission antennas 20b-1 and 20b-2, and the deviation of the installation angle of the reception antennas 31b-1 and 31b-2, all of which are caused by decoding The noise component of the signal is 26.1% or less.
The rotation frequency detection circuits 60-1 and 60-2 have a function of rectifying an input signal, detecting a signal having a frequency of f3 or less, and performing analog / digital conversion.
Input terminals to the rotation frequency detection circuits 60-1 and 60-2 are connected to the rectifier circuit 61. The output side of the rectifier circuit 61 is connected to the low pass filter 62. The output side of the low-pass filter 62 is connected to the A / D converter 63. The output side of the A / D converter 63 is connected to the output terminals of the rotation frequency detection circuits 60-1 and 60-2.

The delay synthesis circuit 40 delays each input signal by a predetermined amount, performs polarization phase rotation for correcting the phase shift θ of the polarization plane due to reflection of the electromagnetic wave, and corrects the phase difference φ of the electromagnetic wave due to the path difference. After performing the phase correction, it has a function of compensating and synthesizing the predetermined amount of delay.
The digital demodulation circuit 47 has a function of demodulating an input digital signal into a baseband signal.
The baseband circuit 48 has a function of processing the input baseband signal.

  In the present embodiment, similarly to the first embodiment, the frequency f1 that is the first frequency is set lower than the frequency f2 of the carrier wave that is the second frequency and the frequency f3 that is the third frequency. . The frequency f2 of the carrier wave is set higher than the frequency f3.

(Operation of Third Embodiment)
FIGS. 6A to 6C are diagrams illustrating the operation of the wireless communication system according to the third embodiment.
FIG. 6A shows time t on the horizontal axis and voltage Vc on the vertical axis. The voltage Vc vibrates finely at the carrier wave f2, and the waveform envelope vibrates greatly at the frequency f3.

  FIG. 6B shows time t on the horizontal axis and voltage Vd on the vertical axis. The voltage Vd vibrates finely at the carrier wave f2, and the waveform envelope oscillates greatly at the frequency f3 and oscillates at a phase shifted by 90 degrees from the voltage Vc.

  FIG. 6C is a three-dimensional view showing temporal changes on the xy plane of the electromagnetic waves transmitted from the transmission antennas 20b-1 and 20b-2 and synthesized. Similarly to the time change of the electromagnetic wave shown in FIG. 3C, the polarization plane of the electromagnetic wave indicated by the waveform of the frequency f2 rotates on the xy plane at the frequency f3. -It becomes spiral in the space of t.

  The radio transmitter 10b modulates the signal modulated by the carrier wave f2 with a signal having a frequency f3 higher than the frequency f2, generates a first output signal, and transmits the first output signal by the transmission antenna 20b-1. Further, the radio transmitter 10b modulates the signal modulated by the carrier wave f2 with a signal obtained by rotating the phase of the frequency f3 by 90 degrees to generate a second output signal, which is 90 degrees with respect to the transmitting antenna 20b-1. It transmits with the transmitting antenna 20b-2 installed at an angle. Since the transmission antenna 20b-1 and the transmission antenna 20b-2 transmit electromagnetic waves having two orthogonal polarization components orthogonal to each other, they do not interfere with each other depending on their installation positions. Therefore, the two transmission antennas 20b-1 and 20b-2 can be bonded in a cross shape and integrated to reduce the size of the entire transmission antenna.

  The radio receiver 30b receives the vertical polarization component of the electromagnetic wave by the reception antenna 31b-1 installed in the vertical direction, and receives the horizontal polarization component of the electromagnetic wave by the reception antenna 31b-2 installed in the horizontal direction. To do. Since the receiving antenna 31b-1 and the receiving antenna 31b-2 receive electromagnetic waves having two orthogonal polarization components orthogonal to each other, they do not interfere with each other depending on the installation position. Therefore, the two receiving antennas 31b-1 and 31b-2 can be bonded in a cross shape and integrated to reduce the size of the entire receiving antenna.

  According to the present embodiment, since two orthogonal polarization components are independent, one piece of information is transmitted and received through two transmission lines that maintain an orthogonal relationship. Accordingly, it is possible to improve reception sensitivity and wireless communication reliability.

  According to the present embodiment, electromagnetic waves arriving at an arbitrary polarization angle can be received by the two integrated receiving antennas 31b-1 and 31b-2. Therefore, it is possible to reduce the size and cost of the apparatus by reducing the number of receiving antennas.

  According to the present embodiment, since it is not necessary to mechanically rotate the transmission antennas 20b-1 and 20b-2, it is not necessary to mount the motor 14 or the like that is a rotating means, contributing to downsizing and high reliability of the device. To do.

(Effect of the third embodiment)
The third embodiment described above has the following effects (G) to (J).
(G) Since the transmission antenna 20b-1 and the transmission antenna 20b-2 transmit electromagnetic waves with two independent polarization components orthogonal to each other, they do not interfere with each other depending on their installation positions. Therefore, the two transmission antennas 20b-1 and 20b-2 can be integrated to reduce the size of the entire transmission antenna.

(H) Since the receiving antenna 31b-1 and the receiving antenna 31b-2 receive electromagnetic waves of two independent polarization components orthogonal to each other, they do not interfere with each other depending on their installation positions. Therefore, the two receiving antennas 31b-1 and 31b-2 can be integrated to reduce the size of the entire receiving antenna.

(I) The electromagnetic waves arriving at an arbitrary polarization angle can be received by the two integrated receiving antennas 31b-1 and 31b-2. Therefore, it is possible to reduce the size and cost of the apparatus by reducing the number of receiving antennas.

(J) Since it is not necessary to mechanically rotate the transmitting antennas 20b-1 and 20b-2, it is not necessary to mount the motor 14 as a rotating means, which contributes to downsizing and high reliability of the device.

(Configuration of Fourth Embodiment)
FIGS. 7A and 7B are schematic configuration diagrams showing a wireless communication system according to the fourth embodiment. Elements common to the elements in FIG. 5 showing the third embodiment are denoted by common reference numerals.

  The radio transmitter 10c illustrated in FIG. 7A includes an information generation circuit 11, an oscillator 12, a modulator 13, and a baseband similar to the radio transmitter 10b illustrated in FIG. 5A according to the third embodiment. A circuit 17 and modulators 18-1 and 18-2 are provided. Furthermore, transmission antennas 20c-1 and 20c-2 different from the wireless transmitter 10b of the third embodiment are provided.

  The transmission antenna 20c-1 and the transmission antenna 20c-2 have a function of transmitting circularly polarized electromagnetic waves, respectively, and are arranged to transmit circularly polarized waves in opposite directions. In the present embodiment, the transmission antenna 20c-1, which is the first transmission antenna, has a function of transmitting a right-handed circularly polarized wave. The transmission antenna 20c-2 as the second transmission antenna has a function of transmitting left-handed circularly polarized waves.

  The transmission antenna 20c-1 and the transmission antenna 20c-2 transmit circularly polarized electromagnetic waves whose rotation directions are opposite to each other. The transmission antenna 20c-1 and the transmission antenna 20c-2 transmit electromagnetic waves having two independent polarization components simply by bonding them so that the rotation directions are opposite. That is, compared with the transmission antennas 20b-1 and 20b-2 of the third embodiment, there is less possibility that polarization components are mixed with each other even if the antennas are not arranged vertically accurately. There is an effect that adjustment is unnecessary.

  The radio receiver 30c shown in FIG. 7B includes rotational frequency detection circuits 60-1 and 60-2 similar to the radio receiver 30b of FIG. 5B showing the third embodiment, and a delay synthesis circuit 40. A digital demodulation circuit 47 and a baseband circuit 48. Furthermore, receiving antennas 31c-1 and 31c-2 different from the wireless transmitter 10b of FIG. 5A showing the third embodiment are provided.

  The receiving antenna 31c-1 that is the first receiving antenna and the receiving antenna 31c-2 that is the second receiving antenna each have a function of receiving circularly polarized electromagnetic waves, and the circular polarizations in the opposite directions to each other. Arranged to receive waves. In the present embodiment, the receiving antenna 31c-1 has a function of receiving a right-handed circularly polarized wave. The receiving antenna 31c-2 has a function of receiving left-handed circularly polarized waves.

  Similarly, the receiving antennas 31c-1 and 31c-2 also transmit electromagnetic waves having two independent polarization components simply by bonding them so that the rotation directions are opposite. That is, there is little possibility that two polarization components are mixed with each other even if they are not installed vertically correctly, and it is easier to manufacture than the receiving antenna 31b-1 and the receiving antenna 31b-2 of the third embodiment. And there exists an effect that adjustment after manufacture is unnecessary.

  In the present embodiment, similarly to the first embodiment, the frequency f1 that is the first frequency is lower than the frequency f2 of the carrier wave that is the second frequency and the frequency f3 that is the third frequency. The frequency f2 of the carrier wave is higher than the frequency f3.

(Operation of Fourth Embodiment)
The radio transmitter 10c of the fourth embodiment is different from the electromagnetic waves composed of the vertical polarization and the horizontal polarization of the radio transmitter 10b of the third embodiment, and the electromagnetic waves composed of the left-hand circular polarization and the right-hand circular polarization. Is similar to the operation of the wireless transmitter 10b of the third embodiment.

  The radio receiver 30c of the fourth embodiment is different from the electromagnetic waves composed of the vertical polarization and the horizontal polarization of the radio receiver 30b of the third embodiment, and the electromagnetic waves composed of the left-hand circular polarization and the right-hand circular polarization. Is the same as the operation of the wireless receiver 30b of the third embodiment.

(Effect of the fourth embodiment)
The fourth embodiment described above has the following effects (K) and (L).
(K) The transmission antenna 20c-1 and the transmission antenna 20c-2 transmit electromagnetic waves having two independent polarization components simply by bonding them so that the rotation directions are opposite. Therefore, it is easy to manufacture and there is an effect that adjustment after manufacturing is unnecessary.

(L) Similarly, the reception antennas 31c-1 and 31c-2 also transmit electromagnetic waves having two independent polarization components simply by bonding them so that the rotation directions are opposite. Therefore, it is easy to manufacture and there is an effect that adjustment after manufacture is unnecessary.

(Configuration of Fifth Embodiment)
FIGS. 8A and 8B are schematic configuration diagrams showing a wireless communication system according to the fifth embodiment. Elements common to the elements in FIG. 7 showing the fourth embodiment are denoted by common reference numerals.

  The radio transmitter 10d illustrated in FIG. 8A includes an information generation circuit 11, a baseband circuit 17, and a transmission antenna 20c-1 that is a first transmission antenna, similar to the radio transmitter 10c of the fourth embodiment. And a transmission antenna 20c-2 which is a second transmission antenna. Furthermore, oscillators 12-1 and 12-2 different from the wireless transmitter 10c of the fourth embodiment, a modulator 13-1 as a first modulation means, and a modulator 13- as a fourth modulation means. 2, an inverting phase shift circuit 15 b, an adder 19-1 as a first combining unit, and an adder 19-2 as a second combining unit.

  The output side of the information generation circuit 11 is connected to the baseband circuit 17. The output side of the baseband circuit 17 and the output side of the oscillator 12-1 are connected to the modulator 13-1. The output side of the baseband circuit 17 and the output side of the oscillator 12-2 are connected to the modulator 13-2.

  The output side of the modulator 13-1 and the output side of the modulator 13-2 are connected to the adder 19-1. The output side of the adder 19-1 is connected to the transmission antenna 20c-1.

  Further, the output side of the modulator 13-2 is connected to the inverting phase shift circuit 15b, and the output side of the inverting phase shift circuit 15b and the output side of the modulator 13-1 are connected to the adder 19-2. Has been. The output side of the adder 19-2 is connected to the transmission antenna 20c-2.

A wireless receiver 30c shown in FIG. 8B has the same configuration as the wireless receiver 30c of the fourth embodiment.
In the present embodiment, the frequency f1 that is the first frequency is lower than any of the carrier frequency f2a that is the second frequency, the carrier frequency f2b that is the fourth frequency, and the frequency f3 that is the third frequency. . The carrier frequency f2a and the frequency f2b are higher than the frequency f3.

(Operation of Fifth Embodiment)
The oscillator 12-1 has a function of outputting the carrier wave f2a that is the second frequency to the modulator 13-1.
The oscillator 12-2 has a function of outputting a carrier wave f2b, which is a fourth frequency slightly different from the carrier wave f2a, to the modulator 13-2. In the present embodiment, the difference between the frequency f2a and the frequency f2b is between 80 percent and 125 percent of the frequency f2a. If the difference between the frequency f2a and the frequency f2b is less than 80 percent or 125 percent or more of the frequency f2a, the frequency of the envelope of the synthesized waves f3 and f3b described later is close to the frequencies f2a and f2b, and the synthesized wave f3 , F3b envelopes are difficult to extract.
The modulator 13-1 has a function of modulating the information signal in the frequency band f1 with the carrier wave f2a that is the second frequency and outputting the modulated signal as a first modulated signal.
The modulator 13-2 has a function of modulating the information signal in the frequency band f1 with the carrier wave f2b, which is the fourth frequency, and outputting it as a fourth modulated signal.
The inverting phase shift circuit 15b has a function of inverting and outputting the first modulation signal.
The adder 19-1 has a function of adding the inverted first modulation signal and the fourth modulation signal and outputting the result to the transmission antenna 20c-1.
The adder 19-2 has a function of adding the first modulation signal and the fourth modulation signal and outputting the result to the transmission antenna 20c-2.

FIGS. 9A and 9B are diagrams illustrating the operation of the wireless communication system according to the fifth embodiment.
In FIG. 9A, the horizontal axis indicates time t, and the vertical axis indicates each signal voltage. The waveform of the carrier wave f2a is indicated by a one-dot chain line, the waveform of the carrier wave f2b is indicated by a chain line, and a synthesized wave f3 obtained by synthesizing them by the adder 19-2 is indicated by a thick line. Due to the slight frequency difference between the carrier wave f2a and the carrier wave f2b, the synthesized wave f3 vibrates finely by the carrier wave (f2a + f2b) / 2, and the envelope of the synthesized wave f3 vibrates greatly at the frequency f3. Here, since the frequencies of f2a and f2b are slightly different from each other, the frequency of the carrier wave included in the synthesized wave is hereinafter referred to as f2a.

  The horizontal axis of FIG.9 (b) shows time t and the vertical axis | shaft has shown each signal voltage. The waveform of the carrier wave f2a is indicated by a one-dot chain line, the waveform of the inverted carrier wave (-f2b) is indicated by a chain line, and the synthesized wave f3b obtained by synthesizing them by the adder 19-2 is indicated by a thick line. Due to a slight frequency difference between the carrier wave f2a and the carrier wave (-f2b), the synthesized wave f3b vibrates finely at the carrier wave f2, and the envelope of the synthesized wave f3b vibrates greatly at the frequency f3. The envelope of the synthetic wave f3b is 90 degrees out of phase with the envelope of the synthetic wave f3.

  According to the radio transmitter 10d of the present embodiment, the output signals of the two oscillators that are slightly shifted in frequency are each modulated as a carrier wave, and the frequency f3 is generated by adding the two modulated signals. . In the time waveform of the signal after the addition, the envelope changes at a frequency | f2a−f2b | which is an absolute value of a frequency difference between the carrier wave f2a and the carrier wave f2b. Instead of the phase shift circuit 15 that rotates the phase by 90 degrees in the fourth embodiment, an inverted phase shift circuit 15b that inverts the signal and rotates the phase by 180 degrees is mounted. Therefore, there is no need to adjust the phase rotation amount of the phase shift circuit 15, and therefore, there is an effect that it contributes to no adjustment of the radio transmitter 10 d.

(Effect of 5th Embodiment)
The fifth embodiment described above has the following effect (M).
(M) Instead of the phase shift circuit 15 that rotates the phase by 90 degrees, an inverted phase shift circuit 15b that reverses the signal and rotates the phase by 180 degrees is mounted, so that the phase rotation amount of the phase shift circuit 15 is adjusted. Therefore, there is an effect that it contributes to the non-adjustment of the wireless transmitter 10d.

(Concept of the sixth embodiment)
FIG. 10 is a diagram illustrating the concept of the delay synthesis circuit according to the sixth embodiment.
The output of the receiving antennas 31c-1 and 31c-2 is connected to the delay synthesis circuit 40 via rotation frequency detection circuits 60-1 and 60-2. The output side of the delay synthesis circuit 40 is connected to the digital demodulation circuit 47. The output side of the digital demodulation circuit 47 is connected to the baseband circuit 48. The output side of the baseband circuit 48 is the output of the radio receiver 30e.

  When the frequency f3 component of the electromagnetic wave received by the receiving antennas 31c-1 and 31c-2 is input, the delay synthesis circuit 40 creates n signals with delay amounts T to nT, and the electromagnetic wave in these delay signals is generated. The signal power is increased by correcting the phase shift θi of the polarization plane, correcting the phase shift φi due to the path difference of the electromagnetic wave, and synthesizing the signal whose delay amount is restored.

  The delay synthesis circuit 40 includes a plurality of reflection phase-shifting delay devices 42 (= 42-1 to 42-n), a plurality of delay devices 43 (= 43-1 to 43-n), and a plurality of adders 44 ( = 44-1 to 44-n), a plurality of path difference phase shift delay devices 45 (= 45-1 to 45-n), and a combiner 46.

  The reflection phase shift delay device 42-i (i is a natural number from 1 to n) has a function of delaying the input signal by (i × T) and correcting the phase shift θi of the polarization plane due to the reflection of the electromagnetic wave. ing.

The delay device 43-i has a function of delaying the input signal by (i × T). The adder 44-i adds the output signal of the reflection phase shift phase shifter 42-i and the output signal of the delay unit 43-i, and receives the multiplexed waves received by the receiving antennas 31c-1 and 31c-2. Each has a function of outputting a polarization signal delayed by a delay time T to 6T.
The adder 44-i has a function of adding the output signal of the reflection phase-shifting delay device 42-i and the output signal of the delay device 43-i.

  Since the polarization plane of the electromagnetic wave rotates with a period of (1 / f3), interference due to the scattering of radio waves occurs with a period of (1 / f3). In order to suppress the interference due to the radio wave scattering, the delay amount T is a value ((1 / f3) / n) that can be sampled evenly with no (1 / f3) period. Thereby, even if radio wave interference occurs at any timing of the delay times T to 6T, it is possible to avoid the phenomenon that electromagnetic wave energy becomes zero due to interference. Furthermore, the present invention is not limited to this, and the delay amount T may be set to an arbitrary value such as an integral multiple of ((1 / f3) ÷ n) period, 1/2 times, 3/2 times, or the like.

  The path difference phase shift delay unit 45-i corrects the phase shift φi due to the path difference of the electromagnetic wave, and aligns the delays of the input signals in the reflection phase shift phase shifter 42-i and the delay unit 43-i. The combiner 46 increases the signal power by combining these signals.

  The output side of the rotation frequency detection circuit 60-1 is connected to the reflection phase shift phase shifter 42-1 to 42-n, and the output side of the rotation frequency detection circuit 60-2 is the delay unit 43-1 to 43-n. It is connected to the. The output side of the reflection phase-shifting delay device 42-1 and the output side of the delay device 43-1 are connected to the adder 44-1. The output side of the adder 44-1 is connected to the path difference phase shift delay unit 45-1. With this connection, the phase shift due to the path difference of the electromagnetic wave is corrected and output to the combiner 46.

  The output side of the reflection phase shift phase shifter 42-i and the output side of the delay unit 43-i are connected to the adder 44-i. The output side of the adder 44-i is connected to the path difference phase shift delay unit 45-i. The phase difference due to the path difference of the electromagnetic wave of the i-th delayed signal is corrected by the path difference phase shift delay unit 45-i and input to the combiner 46. The combiner 46 increases the signal power of the output signal by combining everything from the first delay signal to the nth delay signal.

  The output side of the synthesizer 46 is the output side of the delay synthesis circuit 40 and is connected to the digital demodulation circuit 47. The output side of the digital demodulation circuit 47 is connected to the baseband circuit 48. The delay synthesis circuit 40 can minimize the error rate after demodulation of the digital demodulation circuit 47 by increasing the signal power by correction.

(Configuration of the sixth embodiment)
FIG. 11 is a schematic configuration diagram showing a delay synthesis circuit according to the sixth embodiment.
Similarly to the delay synthesis circuit 40 of FIG. 10, the output sides of the reception antennas 31c-1 and 31c-2 are connected to the delay synthesis circuit 40a via rotation frequency detection circuits 60-1 and 60-2. The output side of the delay synthesis circuit 40 is connected to the digital demodulation circuit 47. The output side of the digital demodulation circuit 47 is connected to the baseband circuit 48. A control signal from the digital demodulation circuit 47 is further connected to the delay synthesis circuit 40a. By this control signal, it is possible to control the correction of the phase shifts θ1 to θn of the polarization plane due to the reflection of the electromagnetic wave and the correction of the phase shifts φ1 to φn due to the path difference of the electromagnetic wave.

  Similarly to the delay synthesis circuit 40 of FIG. 10, the delay synthesis circuit 40a includes a plurality of delay units 43 (= 43-1 to 43-n) and a plurality of adders 44 (= 44-1 to 44-n). And a synthesizer 46. Further, instead of the plurality of reflection phase shift phase shifters 42 (= 42-1 to 42-n), a delay device 43a (= 43a-1 to 43a-n) and a reflection phase shift phase shifter 49 (= 49-1). 49-n), instead of the plurality of path difference phase shift delay units 45 (= 45-1 to 45-n), path difference phase shifters 49a (= 49a-1 to 49a-n) Delay unit 50 (= 50-1 to 50-n).

  The delay device 43a (= 43a-1 to 43a-n) has a function of delaying the input signal by (i × T). The reflection phase shifter 49 (= 49-1 to 49-n) has a function of correcting the phase shifts θ1 to θn of the polarization plane due to the reflection of electromagnetic waves.

  The delay device 43-i has a function of delaying the input signal by (i × T). The adder 44-i adds the output signal of the reflection phase shifter 49-i and the output signal of the delay unit 43-i, and receives the multiplexed waves received by the receiving antennas 31c-1 and 31c-2, respectively. It has a function of outputting a polarization signal delayed by a delay time T to 6T.

  The path difference phase shifters 49a-i have a function of correcting phase shifts φ1 to φn due to the path difference of electromagnetic waves. The delay device 50-i has a function of delaying a signal by a delay time (t2-i × T). As a result, the signals output from the delay units 50-1 to 50-n are all signals delayed by the predetermined time t2. The combiner 46 increases the signal power by combining these signals.

  The output side of the synthesizer 46 is the output side of the delay synthesizer circuit 40 and is connected to the digital demodulator circuit 47a. The output side of the digital demodulation circuit 47 a is connected to the baseband circuit 48. The digital demodulation circuit 47a further has a function of controlling the correction of the phase shifts θ1 to θn of the polarization plane due to the reflection of the electromagnetic waves of the delay synthesis circuit 40a and the correction of the phase shifts φ1 to φn due to the path difference of the electromagnetic waves. . In the present embodiment, the phase shifts φ1 to φn due to the path difference of the electromagnetic waves indicate the phase shift at the frequency f3.

(Operation of the sixth embodiment)
The electromagnetic waves arriving at the receiving antennas 31c-1 and 31c-2 are converted into two digital signals each having a (1 / f3) period by the rotation frequency detection circuits 60-1 and 60-2.

  One digital signal is input to the delay units 43a-1 to 43a-n, and the other digital signal is input to the delay units 43-1 to 43-n and is delayed by a predetermined delay amount.

  Further, the output signals of the delay units 43a-1 to 43a-n are corrected by the reflection phase shifters 49-1 to 49-n, respectively, for the phase shift θi of the polarization plane due to the reflection of the electromagnetic waves. The reflection phase shifters 49-1 to 49-n correct the phase shift θi of the polarization plane, for example, by delaying the input signal by a predetermined time ((θi / 2π) ÷ f3).

  The correction signals output from the reflection phase shifters 49-1 to 49-n and the output signals of the delay units 43-1 to 43-n are added by adders 44-1 to 44-n, respectively. The output signals of the adders 44-1 to 44-n correspond to the delay times T to nT, respectively, and are received signals in which the polarization plane phase shifts θ1 to θn due to the reflection of electromagnetic waves are corrected.

  The output signals of the adders 44-1 to 44-n are corrected by the path difference phase shifters 49a-1 to 49a-n, respectively, to correct the phase shift due to the path difference of the electromagnetic waves, and are delayed by the delay units 50-1 to 50-n. The delay amounts of the respective signals are all the predetermined time t2. The output signals of the delay units 50-1 to 50-n are combined by the combiner 46, and the signal power of the output signal increases.

The electromagnetic waves arriving at the receiving antennas 31c-1 and 31c-2 have a (1 / f3) period when interference due to radio wave scattering occurs because the plane of polarization rotates in the (1 / f3) period. . In order to suppress interference due to the radio wave scattering, the delay units 43-1 to 43-n and the delay units 43a-1 to 43a-n extract the (1 / f3) period evenly and perform signal processing. Therefore, the delay amount unit T of the delay units 43-1 to 43-n and the delay units 43a-1 to 43a-n is a value obtained by dividing the (1 / f3) period by n or (1 / f3). A value obtained by dividing ½ of the period by n. As a result, even if a phenomenon occurs in which electromagnetic wave energy of a specific polarization plane becomes zero due to interference at any timing of the (1 / f3) period due to interference, other polarization planes at other delay times Is not interfering, and the electromagnetic energy is expected not to be zero.
Furthermore, the present invention is not limited to this, and the delay amount T may be set to an arbitrary value such as an integral multiple of ((1 / f3) ÷ n) period, 1/2 times, 3/2 times, or the like.

  FIG. 12 is a diagram illustrating an operation of the wireless communication system according to the sixth embodiment. The horizontal axis shows the operation of the wireless transmitter 10, the transmission path, and the operation of the wireless receiver 30f, and the vertical axis shows the passage of time t.

  The wireless transmitter 10 transmits a training signal at timing T1, which is a training period. This training signal is transmitted to the transmission path. The digital demodulation circuit 47a of the wireless receiver 30f receives this training signal at the timing R1, and corrects the phase shifts θ1 to θn of the polarization plane due to the reflection of the electromagnetic waves so that the intensity of the combined received signal is maximized. The correction of the phase shifts φ1 to φn due to the electromagnetic wave path difference is optimized.

  The wireless transmitter 10 transmits an information signal at timing T2. This information signal is transmitted to the transmission path. The radio receiver 30f receives this information signal at the timing R2, and corrects the phase shifts θ1 to θn of the polarization plane due to the optimized reflection of the electromagnetic wave and the correction of the phase shifts φ1 to φn due to the path difference of the electromagnetic wave. Go and decrypt. The optimization is, for example, changing the correction amount of the phase shifts θ1 to θn of the polarization plane due to the reflection of the electromagnetic wave at each delay time T to nT and adjusting the correction amount of the phase shifts φ1 to φn due to the path difference. .

  In this adjustment, for example, the value of the phase shift θ1 of the polarization plane is changed within a predetermined range to obtain the optimum value, and then the value of the phase shift φ1 due to the path difference is changed within the predetermined range to obtain the optimum value. It can be performed by repeatedly applying the value after the phase shift θ2 of the wavefront and the value after the phase shift φ2 due to the path difference.

  Hereinafter, by repeating the processes of the timings T1 to T2 and R1 to R2, the installation environment of the wireless transmitter 10 and the wireless receiver 30f changes, and the path of electromagnetic waves that reach the wireless receiver 30f from the wireless transmitter 10 It is possible to further avoid communication errors due to radio wave interference even when the frequency changes dynamically.

(Effect of 6th Embodiment)
The sixth embodiment described above has the following effect (N).
(N) During the training period, the amount of correction of the phase shifts θ1 to θn of the polarization plane due to reflection and the amount of correction of the phase shifts φ1 to φn due to the path difference are optimized. Even when the path of the electromagnetic wave that reaches the radio receiver 30f from 10 changes dynamically, it is possible to further avoid communication errors due to radio wave interference.

(Configuration of the seventh embodiment)
FIG. 13 is a schematic configuration diagram showing a delay synthesis circuit according to the seventh embodiment. Elements common to those in FIG. 11 showing the sixth embodiment are denoted by common reference numerals.
The wireless receiver 30g in this example includes a digital demodulation circuit 47 different from the digital demodulation circuit 47a included in the wireless receiver 30f illustrated in the sixth embodiment, and a base included in the wireless receiver 30f illustrated in the sixth embodiment. Except for having a baseband circuit 48a different from the band circuit 48, it has the same configuration as the wireless receiver 30f shown in the sixth embodiment.

  The baseband circuit 48a has a function of controlling the correction amount of the phase shifts θ1 to θn of the polarization plane due to the reflection of the electromagnetic waves of the delay synthesis circuit 40a and the correction amount of the phase shifts φ1 to φn due to the path difference of the electromagnetic waves. Yes.

(Operation of the seventh embodiment)
Based on FIG. 12, the operation of the wireless receiver 30g according to the seventh embodiment will be described.
The wireless transmitter 10 transmits a training signal at timing T1, which is a training period. This training signal is transmitted to the transmission path. The baseband circuit 48a of the wireless receiver 30g receives this training signal at the timing R1, and the phase shifts θ1 to θn of the polarization plane due to the reflection of electromagnetic waves so that the error rate after demodulation of the combined received signal is minimized. And the correction amount of the phase shifts φ1 to φn due to the path difference of the electromagnetic wave are optimized.

(Effect of 7th Embodiment)
The seventh embodiment described above has the following effect (O).
(O) Since the amount of correction of the phase shifts θ1 to θn of the polarization plane due to the reflection of the electromagnetic wave and the amount of correction of the phase shifts φ1 to φn due to the path difference of the electromagnetic wave are optimized during the training period, the installation environment changes, Even when the path of electromagnetic waves reaching the radio receiver 30f from the radio transmitter 10 dynamically changes, the error rate after demodulation due to radio wave interference can be minimized.

(Configuration of Eighth Embodiment)
FIG. 14 is a schematic configuration diagram showing an elevator system according to the eighth embodiment.
The elevator system 100 includes a building 101 that is a vertically long rectangular parallelepiped and an elevator basket 111. Inside the building 101, a space in which the lifting cage 111 is raised and lowered is provided. The elevator cage 111 moves up and down the interior space of the building 101 by a rope and a drive mechanism (not shown).

  A base station radio 102-1 and an antenna 103-1 are installed on the ceiling of the internal space of the building 101, and a base station radio 102-2 and an antenna 103- are installed on the floor of the internal space of the building 101. 2 are installed. The base station radios 102-1 and 102-2 are polarization angle division diversity radios having the same configuration as the radio receiver 30c shown in FIG. 8B. The antennas 103-1 and 103-2 are orthogonally polarized integrated antennas similar to the receiving antenna 31c shown in FIG.

  An antenna 113-1 is provided on the upper surface of the lift cage 111, and an antenna 113-2 is provided on the lower surface. The terminal station radio 112 is a polarization angle division diversity radio similar to the radio transmitter 10d shown in FIG. These antennas 113-1 and 113-2 are orthogonally polarized integrated antennas similar to the transmitting antenna 20c shown in FIG.

(Operation of Eighth Embodiment)
The radio wave transmitted from the terminal station radio 112 is transmitted via the antenna 113-1 and the antenna 113-2. The transmitted radio wave is subjected to multiple reflections by the inner wall of the building 101 and the outer wall of the elevating basket 111 because the internal space of the building 101 is used as a wireless transmission medium. That is, the internal space of the building 101 forms a multiwave interference environment. The radio waves that have received multiple reflections reach antennas 103-1 and 103-2, respectively.

In this embodiment, the polarization angle division diversity enables high-quality wireless transmission even in a multiwave interference environment. Since the elevator basket 111 can be controlled / monitored from the building 101 by wireless connection means, a space in which the elevator basket 111 is raised and lowered by wired connection means such as a cable is not wasted. Therefore, it is possible to improve the transportation capacity by setting the building 101 to a small volume or increasing the size of the lifting cage 111 with the same building 101 volume.
In addition, the lifting cage 111 can be reduced in weight. This is because the weight of wired connection means such as a cable connected to the elevator cage 111 is a weight that cannot be ignored in high-rise buildings.

(Effect of 8th Embodiment)
The eighth embodiment described above has the following effect (P).
(P) Since the elevator basket 111 can be controlled / monitored from the building 101 by wireless connection means, the space in which the elevator basket 111 is raised and lowered by wired connection means such as cables is not wasted. Therefore, it is possible to improve the transport capability by setting the volume of the small building 101 or increasing the size of the lifting cage 111 with the same building 101 volume.

(Configuration of the ninth embodiment)
FIG. 15 is a schematic configuration diagram illustrating a substation equipment monitoring system according to the ninth embodiment.
The substation equipment monitoring system 200 of the present embodiment includes a plurality of substations 201-1 to 201-12 and a plurality of radio base stations 211-1 to 211-4 set in the vicinity thereof. In the present embodiment, the number of transformers 201-1 to 201-12 is greater than the number of radio base stations 211-1 to 211-4.

  Each of the transformers 201-1 to 201-12 includes a terminal station radio 203 that performs polarization angle division diversity and an orthogonal polarization integrated antenna 202. The dimensions of the transformers 201-1 to 201-12 are on the order of several meters.

  Each of the radio base stations 211-1 to 211-4 includes a base station radio 213 that performs polarization angle division diversity and an orthogonal polarization integrated antenna 212. The dimensions of the transformers 201-1 to 201-12 are overwhelmingly larger than the wavelength of electromagnetic waves having a frequency of several hundreds of MHz to several GHz used by the radio equipment.

(Operation of the ninth embodiment)
In the substation equipment monitoring system 200 of the present embodiment, the electromagnetic waves are subjected to multiple reflections by the plurality of transformers 201-1 to 201-12. In the substation equipment monitoring system 200, a multi-wave interference environment is formed.

  The terminal station radio 203 and the base station radio 213 according to the present embodiment can realize high-quality radio transmission even in a multi-wave interference environment by the polarization angle division diversity function, and a plurality of radio base stations 211- 1-211-4 enables remote control and remote monitoring of the transformers 201-1 to 201-12. Therefore, it is possible to solve the problem of high-voltage induced power that becomes a problem when using a cable or the like, and it is possible to eliminate the cable laying cost, and to improve the safety of the control / monitoring system of the transformers 201-1 to 201-12, and Cost reduction is possible.

(Effect of 9th Embodiment)
The ninth embodiment described above has the following effect (Q).
(Q) With the polarization angle division diversity radio of this embodiment, high-quality radio transmission can be realized even in a multi-wave interference environment. Control and monitoring of the substations 201-1 to 201-12 can be performed remotely by a plurality of radio base stations 211-1 to 211-4. Therefore, it is possible to solve the problem of high-voltage induced power that becomes a problem when the wired connection means such as a cable is used, and it is possible to eliminate the cable laying cost, and the safety of the control / monitoring system for the substations 201-1 to 201-12 Improvement and cost reduction are possible.

(Modification)
The present invention is not limited to the above embodiment, and can be modified without departing from the spirit of the present invention. For example, there are the following forms (a) to (b) as usage forms and modifications.

(A) The wireless receiver 30a of the second embodiment includes six receiving antennas 31-1 to 31-6. However, the present invention is not limited to this, and any n receiving antennas (n is a natural number) may be used. At this time, it is desirable that the delay amount T is a value ((1 / f3) / n) that can sample the rotation period of the polarization plane of the electromagnetic wave (1 / f3) without deviation. Alternatively, it is desirable that ((1 / f3) / 2), which is half the rotation period of the polarization plane of the electromagnetic wave, is a value (((1 / f3) / 2) / n) that can be sampled without bias.

(B) The wireless transmitter 10d of the fifth embodiment includes a transmission antenna 20c-1 that is a first transmission antenna that transmits circularly polarized waves, and a transmission antenna 20c-2 that is a second transmission antenna. ing. However, the present invention is not limited to this, and the first transmitting antenna transmits linearly polarized waves, and the second transmitting antenna has a predetermined angle (85 degrees to 95 degrees) with the linearly polarized waves transmitted by the first transmitting antenna. The linearly polarized wave formed may be transmitted.

(C) The polarization angle division diversity wireless transmitter and wireless receiver of the present invention may be applied to wireless communication between a centralized control device in a security system, a door sensor, a window sensor, and the like. This makes it possible to provide a security system that requires high communication quality.

10, 10b, 10c, 10d Wireless transmitter 11 Information generation circuit 12, 12-1, 12-2 Oscillator 13, 13-1 Modulator (first modulation means)
13-2 Modulator (fourth modulation means)
14 Motor (rotating means)
15 Phase shift circuit (phase shift means)
15b Inversion phase shift circuit 16 Oscillator 17 Baseband circuit 18-1 Modulator (second modulation means)
18-2 Modulator (third modulation means)
19-1 Adder (first combining means)
19-2 Adder (second synthesis means)
20 Transmitting antenna (electromagnetic wave transmitting means)
20b-1, 20c-1 Transmitting antenna (first transmitting antenna)
20b-2, 20c-2 transmitting antenna (second transmitting antenna)
30, 30a, 30b, 30c, 30d, 30e Radio receiver 31 Diversity receiving antenna 31b-1, 31c-1 Receiving antenna (first receiving antenna)
31b-2, 31c-2 receiving antenna (second receiving antenna)
32-1 to 32-6 path difference phase shifter (multiple signal correction means)
33 Synthesizer (synthesizer)
34-1 to 34-6 delay units 35-1 to 35-6 delay unit 37 time division switch 37a input side switch 37b output side switch 40, 40a delay synthesis circuit (delay synthesis means)
42 (= 42-1 to 42-n) Reflection phase-shifting delay devices 43 (= 43-1 to 43-n), 43a (= 43a-1 to 43a-n) Delay devices 44-1 to 44-n Addition 45 (= 45-1 to 45-n) Path difference phase shift delay unit 46 Synthesizer 47, 47a Digital demodulation circuit 48, 48a Baseband circuit 49 (= 49-1 to 49-n) Reflection phase shifter 49a (= 49a-1 to 49a-n) Path difference phase shifter 50 (= 50-1 to 50-n) Delay device 60-1 Rotation frequency detection circuit (first rotation frequency detection means)
60-2 Rotational frequency detection circuit (second rotational frequency detection means)
61 Rectifier circuit 62 Low-pass filter 63 A / D converter

Claims (20)

First modulation means for modulating an information signal of a first frequency with a second frequency and outputting a first modulated signal;
Electromagnetic wave transmitting means for transmitting the first modulated signal with two independent polarizations and superimposing a third frequency on the polarization;
A polarization angle division diversity wireless transmitter characterized by comprising: The electromagnetic wave transmitting means according to claim 1,
A transmitting antenna for transmitting the first modulated signal with linear polarization;
Rotating means for mechanically rotating the transmitting antenna at the third frequency and rotating the angle of the linearly polarized wave at the third frequency;
A polarization angle division diversity radio transmitter characterized by comprising: The electromagnetic wave transmitting means according to claim 1,
Second modulation means for modulating the first modulated signal with the third frequency to obtain a first output signal;
A first transmitting antenna for transmitting the first output signal with a first polarization;
Phase-shifting means for shifting the phase of the third frequency by a predetermined angle;
Third modulation means for modulating the first modulated signal with the shifted third frequency to obtain a second output signal;
A second transmitting antenna for transmitting the second output signal with a second polarization;
A polarization angle division diversity wireless transmitter characterized by comprising: The first transmitting antenna is an antenna that transmits linearly polarized waves;
The second transmission antenna is an antenna that is installed at an angle between 85 degrees and 95 degrees with respect to the first transmission antenna, and that transmits linearly polarized waves. Polarization angle division diversity wireless transmitter described in 1. The first transmitting antenna is an antenna that transmits circularly polarized waves,
The polarization angle division diversity wireless transmission according to claim 3, wherein the second transmission antenna is an antenna that transmits circularly polarized waves that rotate in a direction opposite to the first transmission antenna. Machine.   The first frequency is set lower than the second frequency and the third frequency, and the second frequency is set higher than the third frequency. The polarization angle division diversity radio transmitter according to any one of claims 1 to 5. First modulation means for modulating an information signal of a first frequency with a second frequency and outputting a first modulated signal;
Fourth modulation means for modulating the information signal at a fourth frequency slightly different from the second frequency and outputting a fourth modulated signal;
The first modulated signal and the fourth modulated signal are combined to output a first output signal that is further modulated at a third frequency generated by the difference between the second frequency and the fourth frequency. First synthesizing means,
The first modulated signal and the inverted signal of the fourth modulated signal are combined and further modulated at the third frequency generated by the difference between the second frequency and the inverted signal of the fourth frequency. Second combining means for outputting the second output signal,
A first transmitting antenna for transmitting the first output signal with a first polarization;
A second transmitting antenna for transmitting the second output signal with a second polarization;
A polarization angle division diversity wireless transmitter characterized by comprising: The first transmitting antenna is an antenna that transmits linearly polarized waves;
The second transmission antenna is an antenna that is installed between 85 degrees and 95 degrees with the first transmission antenna and that transmits linearly polarized waves. The polarization angle division diversity wireless transmitter described. The first transmitting antenna is an antenna that transmits circularly polarized waves,
The polarization angle division diversity radio transmitter according to claim 7, wherein the second transmission antenna transmits circularly polarized waves that rotate in a direction opposite to the first transmission antenna.   The first frequency is lower than any of the second frequency, the fourth frequency, and the third frequency, and the second frequency and the fourth frequency are higher than the third frequency. The polarization angle division diversity radio transmitter according to any one of claims 7 to 9, wherein the polarization angle division diversity radio transmitter is provided. A polarization angle division diversity radio receiver for receiving electromagnetic waves transmitted by the polarization angle division diversity radio transmitter according to claim 1,
A plurality of antennas for receiving a plurality of input signals by receiving electromagnetic waves transmitted by this polarization angle division diversity wireless transmitter respectively at a plurality of polarization planes;
A plurality of signal correction means for correcting a phase due to a path difference for each input signal and generating a reception signal, respectively.
Combining means for combining a plurality of the received signals;
A polarization angle division diversity radio receiver comprising: A polarization angle division diversity radio receiver that receives electromagnetic waves transmitted by the polarization angle division diversity radio transmitter according to claim 3,
A first receiving antenna that receives the first polarization transmitted by the polarization angle division diversity radio transmitter and obtains a first input signal;
A second receiving antenna that receives the second polarized wave transmitted by the polarization angle division diversity wireless transmitter and obtains a second input signal;
First rotational frequency detection means for generating a first reception signal by blocking the first input signal at a frequency that is at least twice as high as the third frequency;
Second rotational frequency detection means for generating a second received signal by blocking the second input signal at a frequency that is at least twice as high as the third frequency;
A polarization angle division diversity radio receiver comprising delay combining means for delaying and combining the first received signal and the second received signal. The first receiving antenna is an antenna that receives linearly polarized waves;
13. The antenna according to claim 12, wherein the second reception antenna is an antenna that is installed between 85 degrees and 95 degrees with the first reception antenna and receives linearly polarized waves. The polarization angle division diversity wireless transmitter described. A polarization angle division diversity radio receiver that receives electromagnetic waves transmitted by the polarization angle division diversity radio transmitter according to claim 7,
A first receiving antenna that receives the first polarization transmitted by the polarization angle division diversity radio transmitter and obtains a first input signal;
A second receiving antenna that receives the second polarized wave transmitted by the polarization angle division diversity wireless transmitter and obtains a second input signal;
First rotational frequency detection means for generating a first reception signal by blocking the first input signal at a frequency that is at least twice as high as the third frequency;
Second rotational frequency detection means for generating a second received signal by blocking the second input signal at a frequency that is at least twice as high as the third frequency;
A polarization angle division diversity radio receiver comprising delay combining means for delaying and combining the first received signal and the second received signal. The first receiving antenna is an antenna that receives circularly polarized waves;
The polarization angle division diversity wireless transmission according to claim 14, wherein the second receiving antenna is an antenna that receives circularly polarized waves that rotate in a direction opposite to that of the first receiving antenna. Machine. The delay synthesis means according to claim 12 or claim 14 comprises:
For each predetermined delay time, the polarization phase rotation of the first received signal and the second received signal is performed and added,
For each added received signal, perform a path difference phase correction based on the path difference,
A polarization angle division diversity radio receiver characterized by combining the corrected received signals.   17. The polarization angle division diversity radio receiver according to claim 16, wherein the polarization phase rotation and the path difference phase correction are determined so that the combined received signal has a maximum intensity.   17. The polarization angle division diversity according to claim 16, wherein the polarization phase rotation and the path difference phase correction are determined so that an error rate after demodulation of the combined received signal is minimized. Wireless receiver. Polarization angle division diversity radio transmitter according to claim 3 or claim 7,
Polarization angle division diversity radio receiver according to claim 16,
A polarization angle division diversity wireless communication system comprising:
This polarization angle division diversity wireless transmitter performs a predetermined training operation to transmit predetermined known information before transmitting and receiving information,
The polarization angle division diversity wireless receiver determines the polarization phase rotation and the path difference phase correction so that the intensity of the combined received signal is maximized in the predetermined training operation. Polarization angle division diversity wireless communication system. Polarization angle division diversity radio transmitter according to claim 3 or claim 7,
Polarization angle division diversity radio receiver according to claim 16,
A polarization angle division diversity wireless communication system comprising:
This polarization angle division diversity wireless transmitter performs a predetermined training operation to transmit predetermined known information before transmitting and receiving information,
The polarization angle division diversity wireless receiver determines the polarization phase rotation and the path difference phase correction so that an error rate after demodulation of the combined received signal is minimized in the predetermined training operation. A polarization angle division diversity wireless communication system.

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