WO2021224952A1 - Système de communication et procédé de traitement de signal - Google Patents

Système de communication et procédé de traitement de signal Download PDF

Info

Publication number
WO2021224952A1
WO2021224952A1 PCT/JP2020/018478 JP2020018478W WO2021224952A1 WO 2021224952 A1 WO2021224952 A1 WO 2021224952A1 JP 2020018478 W JP2020018478 W JP 2020018478W WO 2021224952 A1 WO2021224952 A1 WO 2021224952A1
Authority
WO
WIPO (PCT)
Prior art keywords
individual
signal
dispersed
observation
broadcast
Prior art date
Application number
PCT/JP2020/018478
Other languages
English (en)
Japanese (ja)
Inventor
川口淳一郎
Original Assignee
合同会社パッチドコニックス
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 合同会社パッチドコニックス filed Critical 合同会社パッチドコニックス
Priority to PCT/JP2020/018478 priority Critical patent/WO2021224952A1/fr
Publication of WO2021224952A1 publication Critical patent/WO2021224952A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems

Definitions

  • the present invention includes an observation object including one reference signal from a broadcast individual and one or more linear spectra of each dispersed individual having an intensity that enables reoscillation by phase synchronization on the individual.
  • the present invention relates to a communication method without a communication system, which comprises an observation target, a plurality of distributed individuals (distributed individuals) that are not connected by wire, and an individual (broadcast individual) that broadcasts a reference signal to them. ..
  • the broadcast individual is also an individual (accumulated individual) that simultaneously accumulates signals from each dispersed individual.
  • an artificial signal source may be arranged in the area of the spatial solid angle to be observed, and this is referred to as a target individual.
  • Patent Document 16 provides an idea for organically connecting these, but the number of transceivers and the process of synchronizing the phases required for the core spacecraft and each distributed spacecraft are complicated. However, there are still problems with low-cost and easy-to-use use.
  • Patent Document 16 lacks practicality due to practical defects or restrictions that the information obtained from the observation target does not function unless it is in the baseband (baseband). In addition, it is vulnerable because it is premised on an analog method in which the observation result signal is processed by integrating the signals from all dispersed individuals.
  • the present invention provides a simple and completely different method that reduces the number of transceivers that make up the system, the process of synchronizing the phases, and does not necessarily have to obtain an integrated signal. In particular, it eliminates analog processes related to signal integration, and as a result, the input / output configuration is completely different from Patent Document 16 and provides a clearly identified new means.
  • One "signal” referred to in the present specification is a signal of a line spectrum which corresponds to a carrier wave and has a strength capable of transmitting a signal by synchronizing the phases, and if a sideband exists, it exists in the sideband.
  • the length of the transmission line from the observation target to the final accumulation point is strictly on the order of wavelength. Must match.
  • the points of accumulation are also called focal points. This is a requirement that constitutes the Ministry of Defense in a broad sense if it is extended to the communication system or the wavelength of light.
  • the receiving and receiving surfaces are basically rigid structures, and the integrated rigid body constructs a paraboloid, and a telescope has been constructed.
  • the region of the spatial solid angle to be observed includes a point source containing one or more linear spectra that can be re-oscillated by phase synchronization on the observed individual.
  • the "center of the observation target” refers to any of the point sources defined in advance. When there is only one point source, the center of the observation target is naturally determined. It is assumed that there is no other point source that emits the line spectrum of the same frequency in the region of the spatial solid angle to be observed. It is assumed that the direction toward the center of the observation target can be identified from any of the dispersed populations.
  • optical axis refers to the direction from any individual in the identifiable group to the center of the observation target.
  • the optical axis is uniquely defined.
  • “Integrating” the signals means adding and superimposing the signals, and the number of output signals is one.
  • Integrating” a signal means receiving the signal separately, and the number of output signals is equal to the number of distributed individuals.
  • “Aggregating signals in phase” means that the signals received by the observed dispersed individuals from the optical axis direction are received in phase with each other at the point where they are integrated.
  • “Integrating signals in phase” means that the signals received by the observed dispersed individuals from the optical axis direction are received in phase, added, superimposed, and received at the point of integration.
  • a “group” or “formation” refers to a set formed by a plurality of dispersed individuals that are not connected by wire and exist in a dispersed manner.
  • the “origin of a group or formation” is defined as the position of one individual in the set of dispersed individuals. In the present invention, the choice of origin biases the phase information but does not affect the results obtained.
  • the “baseline” refers to a vector from the origin to the position of each dispersed individual on a plane perpendicular to the optical axis and passing through the origin of the group or formation. This length is described as the baseline length or the baseline length. The origin of the baseline is the origin of the group or formation.
  • “Position on baseline” refers to the location of each dispersed individual as defined by this baseline.
  • the interferometer described herein is one of the following two. (1) It is possible to obtain a signal that integrates the observation information from the microstructure of the observation target by causing interference at the accumulation point, and to determine the signal intensity distribution in the microstructure from the signal including the phase information. The system and method of doing so. Examples of this include VLBI observations that can collect information by wire and synthetic aperture radar. or, (2) Based on the observation information about the microstructure of the observation target collected from each dispersed individual, the signals from each dispersed individual are accumulated, the phase difference between the signals is obtained, and the signal intensity distribution in the microstructure is obtained. A system and method that makes it possible to determine.
  • the present invention is not necessarily limited to the purpose of interfering with and integrating signals from dispersed individuals. It is an object of the present invention to provide a method capable of receiving and accumulating observation signals from the optical axis direction in the same phase regardless of any dispersed individual. Strict time synchronization is required to use the phase information from each distributed individual, and by making it possible for an individual that accumulates signals to receive signals from the optical axis direction in the same phase, a huge amount of signals on the ground. Processing is greatly reduced. Integration is an operation that brings together the signals collected from all the dispersed individuals, and is one means of compressing the amount of information for estimating the fine structure of the observation target. As a means for compressing the accumulated information, other methods may be adopted as long as the phase information for estimating the fine structure is retained.
  • the obtained signals are accumulated offline, their phases are positively corrected, and they are synthesized through interferometry, etc.
  • Interferometers which obtain structural intensity distributions, are becoming mainstream, especially in the radio region.
  • the application of the retro-directive method in which a plurality of distributed individuals perform a phase operation on a signal from a transmission source and retransmit it, and the transmission source recursively receives the signal in the same phase in real time is advancing. ..
  • the retro-directive method which consists of a large number of moving dispersed individuals such as spacecraft and artificial satellites.
  • the retro-directive method is one of the extremely simplified forms of so-called interferometer technology. As a special application, it refers to processing on a distributed individual that retransmits a conjugated signal to recursively return to the original source.
  • FIG. 1 describes the principle of the telescope with a parabolic mirror as a model in which the telescope is considered as an interferometer.
  • F is the focal point of the parabolic mirror, which is composed of a myriad of small micromirrors.
  • Signals from the observation target that are slightly offset from the optical axis of the telescope by an angle ⁇ are accumulated at a position deviated by f ⁇ on the focal length, where f is the focal length, but the explanation here is accumulated at the focal point. Signals will be described. The same explanation holds for signals that are accumulated at different positions on the focal plane.
  • the signal from the observation target received by one k-th microscope is x2, k, j, which is the distance from the j-th minute observation target to the k-th microscope, and the corresponding k-th microscope.
  • the observed signal is expressed as follows.
  • Ak and j are the signal intensities that reach the k-microscope from the j-observation target. If the distance or representative distance from the k-microscope to the point signal source on the optical axis to be observed is described by x2, k *, and the distance from the corresponding k-microscope to the focal point F is described by x1, k *. Will be.
  • the integrated signals can be expressed as follows.
  • ⁇ indicates the amount of difference of each distance from the representative distance.
  • the coefficient ⁇ j is Is. ⁇ j depends only on the direction j of the minute object to be observed, not by the micromirror. To estimate the microstructure of the observation target is to estimate this ⁇ j.
  • dk the difference in the optical path length of the signal coming from the microstructure is Can be expressed as.
  • ⁇ dk indicates the contribution to the baseline length of the minute aperture perpendicular to the optical axis of the k-micromirror (here, positive and negative are included), but here we consider the reflection at the center of the micromirror and compare it to dk. And it's small enough, so ignore it.
  • the origin of dk can be thought of as the optical axis passing through the focal point of the telescope.
  • any individual of the dispersed individuals existing as a group may be used as the origin.
  • the parabolic mirror has the same X0, regardless of the frequency ⁇ .
  • X0 does not have to be constant, and in narrowband observations, it may differ by an integral multiple of the wavelength.
  • the signal from the micromirror l is different from this sum (x2, l * + x1, l *) X0 by an integral multiple of the wavelength even if it is not on the same parabolic mirror.
  • signals from the optical axis direction are accumulated in the focal point in the same phase. By utilizing this property, signals can be accumulated from each dispersed individual in the same phase without absolutely matching the optical path lengths for all dispersed individuals within a specific narrow wavelength band.
  • the established band is narrow, and it is not possible to build a wide band. This is the principle of constructing an interferometer with dispersed individuals without the need for a single rigid individual, and the present invention describes this method.
  • the micromirror is not constrained on the paraboloid and is treated as a dispersed individual. Instead of the reflection of the mirror, the signal received by each dispersed individual is treated as an accumulation point via signal processing. , It is a method of retransmitting to the accumulated individual.
  • the microstructure of the observation target appears in the third term in (Equation 7).
  • phase of the third term of (Equation 6) and (Equation 7) is It is written in the format of and appears in the phase information ⁇ l.
  • the vector cl (L) contains the distance on the baseline from the origin on the plane perpendicular to the optical axis of the micromirror l (L).
  • the signals from each dispersed individual can be received and integrated in the same phase, that is, the signals from the optical axis direction can be received and integrated, they can be detected (product demodulated) and used as the j-component of the vector cl (el). Can be obtained, and ⁇ can be obtained by solving simultaneous equations by multiple observations, and the resolution is improved.
  • dl (el) is zero, and the result shows that the sensitivity is zero for any signal from the fine structure ⁇ l (el), which means that ⁇ dl (el) is dl (el). ) Is overwhelmingly smaller than the result of the approximation.
  • FIG. 2 describes a method of signal generation by a transponder on each distributed individual by the retrodirective method.
  • the original signal from the source to be observed is generally It is expressed by.
  • ⁇ is a carrier frequency or a representative frequency.
  • A represents the signal strength
  • ⁇ 0 represents the phase information obtained by performing phase modulation on the communication data in communication or the like.
  • signals from each microstructure direction of the observation target area existing as a surface are superimposed and correspond to the received phase information.
  • the phase information has a very low frequency and a very long wavelength as compared with the carrier wave.
  • the phase information is treated as a fixed phase in the process of performing in-phase equalization in a narrow band including a carrier wave.
  • the distance to the original source is x, and the signal that is received back to the original source through the reverse path is Therefore, the received signal is Will be.
  • the point where the signal is accumulated is limited to the point of the source that is the original observation target, and the practical range is limited.
  • the range of practical use is expanded by setting the point of accumulation as a specific predetermined individual. Achieving this with a simple configuration is a method for solving the problems described in the present invention.
  • each dispersed individual can obtain a time that can be shared, that is, if a clock that can be shared can be obtained, it is easy to accumulate signals at a certain point.
  • the phase-locked loop can coherently and passively determine the oscillation frequency generated on each dispersed individual, that is, the clock can be determined.
  • each distributed individual generates a signal from its own local oscillator that has a rational ratio to the signal it receives.
  • the dispersed individual has the same frequency as the signal received from the observation target. This is the case when the time signal of is generated.
  • ⁇ 0 is the initial phase of the local oscillator.
  • ⁇ 0 can be shared by all the distributed individual transmitters, the phases from all the distributed individuals returning to the original transmission source can be shared and integrated. However, the initial phase ⁇ 0 of the local oscillator on each distributed individual is disjointed. Even if a reference signal source is provided, one ⁇ 0 is generated, and it is delivered to each dispersed individual by radio waves, the distance from the reference signal source to each dispersed individual varies, so that the distance from the reference signal source to each dispersed individual varies. ⁇ 0 cannot be shared by the placed transmitters. Therefore, the signal can no longer be used as a reference, the signal cannot be accumulated at a certain point other than the original transmission source, and the problem cannot be solved by this method as it is.
  • the transponders on each distributed individual can share the clock, that is, time synchronization can be realized. This is the method that is usually introduced.
  • the oscillation frequency of each dispersed individual is set in each dispersed individual. It is limited to the case where the received signal is coherently generated, or a wired transmission line in which the amount of phase change due to propagation is determined in advance is provided. Moreover, in the retrodirective method, the point that a signal can be obtained from a transponder on each distributed individual in the same phase is limited to the original transmission source.
  • FIG. 3 An example of a typical prior art described in Patent Document 1 is shown in FIG.
  • a Phase Reference Signal is supplied to each node, but as the supply method, the method described in the specification is: ”To ensure an identical reference phase at each node, phase-matched transmission lines (ie, transmission lines having matched propagation delays L / v, where L is the linelength and v is the propagation velocity) transport the reference signal from the sourceto each array node.
  • phase-matched transmission lines ie, transmission lines having matched propagation delays L / v, where L is the linelength and v is the propagation velocity
  • Patent Document 1 has a strength that enables re-oscillation by phase synchronization on each dispersed individual with "one reference signal from the broadcast individual" as in the present invention described later.
  • Patent Document 2 does not deal with conjugated phase generation, but relates to a wireless charging method, and as described in the present invention described later, "a reference signal from a broadcast individual and a reference signal. Signals in one or more bands from an observation target containing one or more linear spectra having an intensity capable of reoscillating by phase synchronization on each dispersed individual were used. It does not deal with a method of compensating for phases involved in spatial propagation independently of each other and a simple method of accumulating interference signals identified for each dispersed individual by the broadcast individual.
  • Patent Document 3 has only one beacon as a pilot signal, and cannot compensate for the phase shift due to the spatial distance from the reference signal generator.
  • Patent Document 4 has only one pilot signal as a pilot signal, and as in the present invention described later, "one reference signal from a broadcast individual and each dispersed individual, the said Phases related to spatial propagation using signals in one or more bands from an observation target containing one or more linear spectra with intensities that allow reoscillation by phase synchronization on an individual are mutually independent of the phases involved in spatial propagation. It does not deal with the compensation method and the simple accumulation method of the interference signal identified for each dispersed individual by the broadcast individual.
  • Patent Document 5 has only one Communication Source as a pilot signal, and as in the present invention described later, "one reference signal from a broadcast individual and each dispersed individual, the said Phases related to spatial propagation using signals in one or more bands from an observation target containing one or more linear spectra with intensities that allow reoscillation by phase synchronization on an individual are mutually independent of the phases involved in spatial propagation. It does not deal with the compensation method and the simple accumulation method of the interference signal identified for each dispersed individual by the broadcast individual.
  • Patent Document 6 has only one input to the Conjugator as a pilot signal, and as in the present invention described later, "one reference signal from a broadcast individual and each dispersed individual, Phases involved in spatial propagation using signals in one or more bands from an observation target containing one or more linear spectra with intensities that allow reoscillation by phase synchronization on the individual. It does not deal with an independent compensation method and a simple accumulation method of interference signals identified for each dispersed individual by the broadcast individual.
  • Patent Document 7 does not deal with conjugated phase generation, but relates to a wireless charging method, and as described in the present invention described later, "a reference signal from a broadcast individual and a reference signal. Signals in one or more bands from an observation target containing one or more linear spectra having an intensity capable of reoscillating by phase synchronization on each dispersed individual were used. It does not deal with a method of compensating for phases involved in spatial propagation independently of each other and a simple method of accumulating interference signals identified for each dispersed individual by the broadcast individual.
  • Patent Document 8 has only one beacon as a pilot signal, and cannot compensate for the phase shift due to the spatial distance from the reference signal generator.
  • Patent Document 9 has only one pilot signal as a pilot signal, and as in the present invention described later, "one reference signal from a broadcast individual and each dispersed individual, the said Phases related to spatial propagation using signals in one or more bands from an observation target containing one or more linear spectra with intensities that allow reoscillation by phase synchronization on an individual are mutually independent of the phases involved in spatial propagation. It does not deal with the compensation method and the simple accumulation method of the interference signal identified for each dispersed individual by the broadcast individual.
  • Patent Document 10 has only one Communication Source as a pilot signal, and as in the present invention described later, "one reference signal from a broadcast individual and each dispersed individual, the said Phases related to spatial propagation using signals in one or more bands from an observation target containing one or more linear spectra with intensities that allow reoscillation by phase synchronization on an individual are mutually independent of the phases involved in spatial propagation. It does not deal with the compensation method and the simple accumulation method of the interference signal identified for each dispersed individual by the broadcast individual.
  • Patent Document 11 has only one input to the Conjugator as a pilot signal, and as in the present invention described later, "one reference signal from a broadcast individual and each dispersed individual, Phases involved in spatial propagation using signals in one or more bands from an observation target containing one or more linear spectra with intensities that allow reoscillation by phase synchronization on the individual. It does not deal with an independent compensation method and a simple accumulation method of interference signals identified for each dispersed individual by the broadcast individual.
  • Patent Document 12 has a configuration in which each individual is provided with an optical phase synchronization mechanism. Although this system solves the problem of recursive orientation, it requires a multi-element antea with a very large number of elements, which makes each individual expensive and impractical.
  • Patent Document 13 deals with a device for accurately synchronizing the pilot signal by spreading the spectrum, and as in the present invention described later, "with one reference signal from a broadcast individual". Signals in one or more bands from an observation target containing one or more linear spectra having an intensity that enables reoscillation by phase synchronization on each dispersed individual were used. It does not deal with a method of compensating for phases related to spatial propagation independently of each other and a simple method of accumulating interference signals identified for each dispersed individual by the broadcast individual.
  • Patent Document 14 deals with a method in which pilot signals are distributed to each transmission unit by a distributor and via a phase difference detection cable, but there is only one pilot signal, and the present invention described later.
  • An observation target containing one reference signal from a broadcast individual and one or more linear spectra of each dispersed individual having an intensity that enables reoscillation by phase synchronization on the individual.
  • Patent Document 15 has only one pilot signal, and as in the present invention described later, "one reference signal from a broadcast individual and a phase on each dispersed individual on the individual".
  • a simple method of accumulating interference signals identified for each dispersed individual by the broadcast individual "is not dealt with.
  • the technique described in Patent Document 16 is The broadcast individual receives a signal of one wavelength from the observation target and relays it to each dispersed individual by broadcasting, a reference signal broadcast from the broadcast individual, and each dispersed individual. It is involved in a phase compensation method that is independent of each other related to spatial propagation using a signal of one wavelength from the observation target, and a homogenization method based on a signal accumulation method by the broadcast individual. Accumulation as used in this technique refers to integration as used herein, and the observation result signal obtained as a result of this technique is very restrictive.
  • the signal received from the observation target is a signal of one frequency, but it is necessary to transmit two types of signals from the broadcast individual.
  • the technique of the present invention 1 from an observation target containing one reference signal from the broadcast individual and one or more linear spectra of each dispersed individual having an intensity that allows reoscillation by phase synchronization on the individual. It is a method of compensating for phases related to spatial propagation that are independent of each other using signals of one or more bands, and a simple method of accumulating interference signals identified for each dispersed individual by the broadcast individual. The method is completely different from the technology of.
  • the broadcast individual requires one receiver and one transmitter, and each distributed individual requires at least one receiver and one transmitter.
  • the frequency for communication in the entire system may be two waves.
  • the number of receivers on each distributed individual is three. Therefore, the system of the broadcast individual that also serves as an accumulated individual is considerably simplified as compared with the technique of the document, and it is possible to perform a simpler accumulation.
  • the frequency for communication in the entire system is two waves, which is more feasible. Even if each dispersed individual receives two waves from the observation target, it does not exceed the method of Patent Document 16, and the entire system is greatly simplified. This is because it utilizes the fact that the transmission source to be observed is prepared in advance.
  • U.S. Patent Application Publication No. 20130002472 Active retrodirective antenna array with a virtual beacon
  • U.S. Pat. No. 9,900,057 Systems and methods for assigning groups of antennas of a wireless power transmitter to different wireless power receivers, and determining effective phases to use for wirelessly transmitting power using the assigned groups of antenna
  • U.S. Pat. No. 9,887,589 Systems and methods for improved phase determinations in wireless power delivery environments
  • U.S. Pat. No. 9,356,666 Oilator and recipient based transmissions in wireless communications
  • U.S. Pat. No. 9,325,403 Digital retro-directive communication system and method thereof
  • the keywords that characterize the present invention are "wireless system”, “real-time processing”, “elimination of two-way communication”, “simple realization of communication system as an interferometer”, and “identified for each distributed individual”. Information gathering “. Simultaneous solution of these is a problem in the prior art.
  • “simple” refers to restrictions on the number of signals to be set, that is, frequency bands, and simplification of the transmission / reception system.
  • Being a “wireless system” greatly alleviates the difficulty of using it in free-flying and mobile objects.
  • the wired system was predominant.
  • real-time processing offline correlation processing, equipment and work can be eliminated. In most cases, the conventional method requires offline processing such as correlation processing.
  • the present invention states that the integration is not necessarily recursive to the original source and returns the signal in the same phase at a frequency different from the predetermined reception frequency in any specified direction for the number of frequency bands to be set. It makes it possible while simplifying the restrictions and transmission / reception system.
  • the ability to "collect information identified for each dispersed individual" means that the observation result signal, which had to be output by integrating the signals from the observation targets with conventional radars, is optional for the accumulated individuals in this method. It is shown that each dispersed individual can be identified and obtained by retransmitting at different frequencies of the above and by enabling each dispersed individual to be distinguished from each other by an appropriate code when retransmitting.
  • the phase processing of the signals received by a plurality of dispersed individuals was limited to the statistical method of offline time adjustment called correlation processing.
  • the retrodirective method has been realized for the method related to recursive folding accumulation and focusing, which eliminates the uncertainty of the distance from the observation target in real time. There is only.
  • the signal processing in each dispersed individual is controlled by the initial phase of the local signal source on the individual, that is, there is a problem that the time is not controlled between the individual receiving the accumulation and the light collection.
  • the time synchronization itself can be achieved on each distributed individual if the signals distributed from the reference signal source are delivered at different frequencies. However, this requires signal transmission at multiple frequencies from the broadcast individual, and if the accumulation point does not match the source of the observation target, the time synchronization with the observation target, in other words, the distance from the observation target The elimination of uncertainty remains unresolved.
  • the distance information for the observation target of each dispersed individual can be offset and removed only when it is recursively accumulated in the observation target.
  • the problem to be solved is accumulation regardless of the distance from the reference signal source to each dispersed individual (first relative distance) and regardless of the distance from the observation target to each dispersed individual (second relative distance).
  • the response from each dispersed individual that is, the retransmission signal
  • the system can be configured only with a wireless medium without being freed from the physical constraint of requiring a cable, that is, a cable, and the integration and condensing functions can be exhibited in real time instead of the correlation processing.
  • the integration and condensing system can be configured by independent processing on each distributed individual, which eliminates bidirectional communication and each distributed individual depends only on the received information from the observation target and the reference signal source (independent dispersion).
  • the signal retransmitted in response can be accumulated and collected in the same phase by specifying an arbitrary accumulation location in advance, in addition to simply returning the recursiveness to the source of the observation target. It is to build a group of dispersed individuals.
  • the number of signals transmitted from the broadcast individual is limited to one, which greatly simplifies the system.
  • the present invention simply configures a communication system as a radio wave interferometer by disconnecting a cable, and makes time adjustment function in real time instead of statistical processing. While adopting an independent distributed processing method in which distributed individuals perform processing depending only on received information, retransmitted signals are accumulated at points that are not necessarily recursive, and the optical axis is applied to integrated individuals that are not necessarily fixed in space. With respect to signals from the direction, it solves the problem of configuring a communication system that processes signals that are in phase and are integrated and collected.
  • the system From the observation target, a plurality of dispersed individuals that wirelessly receive observation signals of one or more frequencies, including one or more linear spectra having an intensity that enables reoscillation by phase synchronization on the individual. It is a communication system that has and generates an observation result signal based on a signal generated in each of the plurality of dispersed individuals. It has a broadcast individual that wirelessly transmits a predetermined reference signal to the plurality of dispersed individuals.
  • Each of the plurality of dispersed individuals Upon receiving the reference signal from the broadcast individual, Further, from the observation signal received from the observation target, as an individual observation result signal that does not depend on the first relative distance between the dispersed individual and the broadcast individual and the second relative distance between the dispersed individual and the observation target. It is provided with a signal processing unit that independently generates a signal to be received and accumulated in the same phase in the broadcast individual from the dispersed individual other than the dispersed individual, and the signal generated by the signal processing unit is wirelessly generated. Retransmit to the broadcast individual The broadcast individual receives the individual observation signal from each of the plurality of dispersed individuals, identifies each of the dispersed individuals, and accumulates phase information regarding the observation target. It becomes a composition.
  • FIG. 1 is a diagram for explaining the principle that a telescope constitutes an interferometer and the phase information in the present invention.
  • FIG. 2 is a diagram showing signal generation of a retrospective transponder.
  • FIG. 3 is a diagram showing a typical example of the conventional retro directive method.
  • FIG. 4 is an example of distance measurement in communication, and is a diagram that provides an example of phase information.
  • FIG. 5 is an explanatory diagram in which a carrier wave, a subcarrier wave, and communication data in communication form phase information.
  • FIG. 6 is a diagram showing the principle of signal processing in the communication system according to the embodiment of the present invention.
  • FIG. 7 is a system diagram of the signal processing shown in FIG.
  • FIG. 8 is a diagram showing a first configuration example of a communication system applied to observation.
  • FIG. 9 is a diagram showing a second configuration example of a communication system applied to observation.
  • FIG. 10 is a diagram showing a first application example to the retrodirective return of the communication system.
  • FIG. 11 is a diagram showing a second application example to the retrodirective return of the communication system.
  • FIG. 12 is a diagram showing the principle of signal processing in a communication system including a target individual.
  • FIG. 13 is a diagram showing a configuration example of a communication system (including a target individual) applied to astronomical observation.
  • FIG. 14 is a diagram showing a communication system (including a target individual) applied to real-time orbit determination of a deep space probe on a hemispherical scale.
  • FIG. 10 is a diagram showing a first application example to the retrodirective return of the communication system.
  • FIG. 11 is a diagram showing a second application example to the retrodirective return of the communication system.
  • FIG. 12 is a diagram showing the principle of signal processing in a communication system including a target
  • FIG. 15 is a diagram showing a communication system (including a target individual) applied to astronomical observation on a hemispherical scale.
  • FIG. 16 is a diagram showing an example of processing an analog signal in an application to astronomical observation and communication.
  • FIG. 17 is a diagram showing an example of a method of retransmitting to an integrated individual in application to astronomical observation and communication.
  • FIG. 18 is a diagram listing the assigned frequencies of the deep space communication band-1.
  • FIG. 19 is a diagram listing the assigned frequencies of the deep space communication band-2.
  • a feature of the communication system is that an individual generating one reference signal to be shared by each distributed individual broadcasts the reference signal to each individual that disperses the reference signal.
  • One or more of the dispersed individuals containing the reference signal independently of the other dispersed individuals and one or more linear spectra having an intensity capable of reoscillating from the observation target by phase synchronization on the individual.
  • Receives signals that are observation information of multiple frequencies generates signals that have undergone phase adjustment processing via a mixing / high / low frequency filter, and retransmits the processed signals to the broadcast individual. There is.
  • the signals retransmitted from each dispersed individual in the broadcast individual are accumulated in the same phase with respect to the signal from the optical axis direction.
  • the present invention provides a method for easily realizing the mode leading to this accumulation. That is, "from an observation target containing one reference signal from the broadcast individual and one or more linear spectra of each dispersed individual having an intensity that enables reoscillation by phase synchronization on the individual. , A method of compensating for phases related to spatial propagation independently of each other using signals of one or more bands, and a simple method of accumulating interference signals identified for each dispersed individual by the broadcast individual. " be.
  • This communication system is composed of an observation target, a broadcast individual (and a communication device on the individual), and a plurality of dispersed individuals (and a communication device on the individual) used for observation scattered as a group. In this communication system, the broadcast individual is also an integrated individual at the same time.
  • this signal is strong enough, it can be coherently received (received synchronously) and the "product" operation repeated m times to extract the high frequency components. Result is Therefore, the phase delay associated with the propagation distance x is also multiplied by m.
  • a method of obtaining an m-fold sine wave for example, there is a method of phase synchronization processing instead of the "product" operation. In that case, the obtained signal is, for example, as follows. This result is different from the result of the "product" operation. That is, the result may depend on the processing method.
  • phase adjustment method by a simple "product" process is intentionally referred to, but it should be mentioned in advance that the result is essentially the same even if the process is performed by the phase synchronization process.
  • signals of one or more frequencies are obtained from the observation target, but here, as an example, it will be described that signals of two different frequencies can be received from the observation target.
  • the ratio of the two frequencies is a rational number.
  • One of the two signals may be transmitted from another radio wave source existing in the same reception direction, for example.
  • x2 is the distance from the source of observation to each dispersed individual.
  • the information obtained from the spatial solid angle of the observation target does not explicitly depend on the distance from the origin of the group to the dispersed individual, but when the actual observation position is changed, it is fine around the optical axis.
  • the optical path lengths of the signals from the structure will be different. This notation represents this.
  • the two waves both have a carrier wave and a phase component.
  • the explanation is given as the phase information existing on the carrier wave and its sideband, and an example in which a coherent signal can be generated on the carrier waves of the two signals is given.
  • the phase component is constant regardless of each dispersed individual in the case where the observation target is a point source, that is, in the direction of the optical axis.
  • the phase information is expressed differently for each dispersed individual to be observed. This improves the space separation possibility as an interferometer.
  • n ⁇ is only a carrier wave
  • the signal source that generates the carrier wave is a point source. That is, in such a case, ⁇ 0n is interpreted to indicate a certain fixed phase, and is constant regardless of the dispersed individuals.
  • the number of signals to be observed and received remains two, but as a simpler method, there is a case where one signal, for example, n ⁇ , does not exist at all and only one wave is used.
  • a coherent (synchronized) signal on the m ⁇ carrier wave itself on each dispersed individual it is possible to extract the phase information ⁇ 0 m related to the fine structure of each dispersed individual.
  • the number of signals received from the observation target is one.
  • only the phase information may exist on the m ⁇ side, that is, there may be no carrier wave that can be synchronized in real time, and only the point source of the carrier wave may exist on the n ⁇ side.
  • the optical axis is a point source that is the carrier source of n ⁇ , and only appears as a bias in the extracted phase.
  • the phase information of the virtual carrier wave having a frequency of m ⁇ can be shared.
  • the phase information reflects the information of the fine structure to be observed.
  • the number of signals to be observed is two, but the linear spectral source that defines the optical axis is the point source.
  • phase information on the fine structure for each dispersed individual it is necessary to include a linear spectrum corresponding to a carrier wave capable of generating a coherent (synchronous) signal from some observation target. .. Even if there are many signals to be received, if there is no signal corresponding to a carrier wave source capable of generating a coherent (synchronized) signal, it is not possible to obtain phase information regarding the fine structure for each dispersed individual by this method. Moreover, the optical axis itself cannot be defined.
  • the obtained phase signal is a direct current or low frequency signal, and needs to be mounted on some carrier wave and integrated. Twice
  • the problem is that an individual is provided at a point to be accumulated, a reference signal is broadcast from the individual to each dispersed individual, and each dispersed individual generates a coherent signal to the reference signal, and the phase information described above is used.
  • the solution is to carry the modulated signal, re-modulate it, and retransmit the reference signal to the broadcast individual.
  • the broadcast individual is an individual that transmits the reference signal, and is also described as an integrated individual in the sense that signals from each dispersed individual are accumulated at the same time.
  • This solution takes advantage of the retro-directive nature built between the broadcast individual and each distributed individual. The distance between the broadcast individual and each dispersed individual does not appear in the result, and it is possible to accumulate signals while maintaining the broadcast property.
  • phase information of the sideband is, of course, the interference information that is buried below the angular resolution of one telescope and is the overlap of the received waves from a plurality of microscopic observation targets.
  • distance measurement is given as an example.
  • signals exhibiting a plurality of line spectra 51 to 53 are provided in the sideband band, and the carrier wave 50 is modulated by them.
  • the phase information of these sidebands undergoes phase shift with distance propagation, and distance measurement is performed based on the phase shift.
  • the carrier frequency and the frequency of the subcarrier included in the phase information are generated in a rational ratio, the phase information of the communication data existing in the sideband of the subcarrier can be efficiently extracted.
  • phase information related to the fine structure of the observation target can be obtained for each dispersed individual.
  • the phase component of the received observation signal is the sum of the initial phase of the carrier wave and information having different optical path lengths for each microstructure part. If a coherent carrier wave signal can be obtained from the observation signal, for example, the initial phase of the carrier wave is If zero Can be generated, and phase information due to the fine structure of the observation target can be obtained. In this case, the number of signals to be observed is one.
  • this method cannot complete the processing in one wave band in any application.
  • the observation target is a celestial body, it is generally difficult to extract it in real time from the received information without integrating it and oscillate a coherent signal based on it.
  • a signal of sufficient strength having a frequency of the observation frequency and a rational ratio is acquired from the region of the spatial stereoscopic angle of the observation target, a coherent signal is oscillated, and based on that, the observation target sends the signal.
  • the frequency of the signal is corrected to obtain the phase information to be shared, which is the observation data. That is, observation signals of two or more frequency bands are required.
  • the frequency correction signal is independently generated and used on each dispersed individual, a phase shift peculiar to each is generated, so that it is not possible to secure information in the same phase from each dispersed individual.
  • the observation signal includes the main carrier signal and can be received with sufficient intensity, and if a signal can be generated in synchronization with it on each distributed individual, the number of signals received from the observation target. Can be one wave.
  • the carrier frequency fluctuates due to various factors or the carrier is not received from the observation target, a signal with sufficient strength of rational ratio different from the observation target is received, and a coherent signal is received based on the signal. It is necessary to correct the phase of the main observation signal by generating That is, two or more observation frequency bands are required.
  • the frequency correction signal is independently generated and used on each dispersed individual, a phase shift peculiar to each is generated, so that it is not possible to secure information in the same phase from each dispersed individual.
  • phase information can be obtained and shared among the dispersed individuals. In this case, there is only one signal band to observe.
  • a signal including the subcarrier can be acquired on each distributed individual.
  • FIG. 5 is an example showing phase information in communication.
  • the spectrum 52 formed in the sideband band of the subcarrier 51 is the result of phase modulation by communication data and is phase information.
  • the data to be modulated contains a high frequency signal, the spectrum has a large width centered on the subcarrier 51, and it becomes gradually difficult to share the spectrum collectively in the same phase.
  • the frequency of the subcarrier is selected as the frequency of the main carrier and a rational ratio, especially a fraction, the generated signal is not only coherent to the main carrier but also coherent to the subcarrier. Therefore, only the phase information of the sideband around the subcarrier can be acquired on each distributed individual.
  • the signal source is a point source, and no phase shift occurs due to the fine structure.
  • the frequency of the signal emitted by the broadcast individual and the frequency of the signal that the individual accumulates as an integrated individual have a rational number ratio.
  • the frequency of the signal transmitted from the observation target does not have to be in a rational ratio with the broadcast and the integrated frequency.
  • the three frequencies must be explicitly separated to avoid interference.
  • the frequency of the observed signal is intentionally described as 1 ⁇ , and it is clarified that the signals are separated. It does not indicate that the frequency of the reference signal forms a rational ratio with the frequency of the observed signal.
  • the frequency of the basic unit is set to 1 ⁇ .
  • This signal is generated on a local oscillator (LOC) on the broadcast individual.
  • LOC local oscillator
  • ⁇ 0 is a fixed initial phase determined by LOC.
  • q a reference signal is generated and broadcast to each dispersed individual in the system.
  • q itself can be any real number, not necessarily a rational number. That is in each dispersed individual Is received.
  • x1 is an unknown distance (first relative distance) between the broadcast individual and one dispersed individual.
  • Each dispersed individual receives one or more signals of multiple frequencies with rational ratios to each other from the original observation target F2.
  • processing with two waves will be described, but one wave or three or more waves may be used.
  • the condition related to the number of signal bands is that one or more line spectra having the strength to coherently (synchronize) generate signals on a dispersed individual are 1 in the region of the spatial solid angle to be observed. There is more than one.
  • the two observation frequencies are m times and n times the frequency of the basic unit. When there are two signals to observe, m and n take a rational ratio. They are received on each disperse and on each disperse Is obtained.
  • ⁇ m and ⁇ n are the initial phases determined by the observation target, but when the observation target has a microstructure rather than a point source, each dispersed individual is positioned from the origin in the plane perpendicular to the optical axis. It depends. In astronomical observation, it is phase superposition information caused by a fine structure for performing decomposition processing from an interference signal, or in communication, it is communication data information by phase modulation.
  • x 2 is the relative distance (second relative distance) between each dispersed individual and the observation target F2.
  • the broadcast reference signal is combined with the observation signal obtained from the observation target, and an appropriate high / low frequency filter (signal processing unit) is applied.
  • This signal is multiplied by k / (q + m + n) to obtain the signal to be retransmitted to the broadcast individual F1.
  • the phase of this signal is generally Will be.
  • z indicates the distance to a certain receiving point with respect to each dispersed individual. If z reaches the broadcast individual F1, this is – x1.
  • the high / low frequency filter used in the processing is a phase-locked loop processing (Phase Lock Loop processing) that extracts a specific frequency component by matching the phase with a specific frequency even if it is not a "product" operation. You may.
  • FIG. 7 shows a system diagram of signal processing which is the basis of this method.
  • the signal sent from the broadcast individual F1 to each dispersed individual is the reference signal.
  • each dispersed individual receives observation signals of one or more different frequencies from the original observation target F2.
  • the observed signal to be received is not limited to two waves, but may be one wave or a plurality of multiple waves having a rational ratio to each other in general. Strictly speaking, the number of required signals is determined under the condition that one or more linear spectra having an intensity that enables re-oscillation by phase synchronization are present on the individual from the observation target.
  • each dispersed individual performs phase adjustment processing by individually performing independent processing based on the reference signal and the observation signal.
  • the signal obtained as a result is retransmitted from each dispersed individual to the broadcast individual F1 which is the accumulation point.
  • the broadcast individual that is, the accumulated individual, only needs to be equipped with one transmitter that broadcasts to each dispersed individual and one receiver that simultaneously receives and accumulates from each dispersed individual, and the system is very simple to realize. Will be done.
  • integration and integration are different, and when signals from individual dispersed individuals are received by frequency identification, even if there is only one received signal band, there are multiple channels. It may be received at.
  • the present invention includes "one reference signal from a broadcast individual and one or more linear spectra of each dispersed individual having an intensity that allows reoscillation by phase synchronization on the individual.
  • the purpose is to retransmit the processed signal from each dispersed individual, and to identify and accumulate each dispersed individual by the broadcast individual F1.
  • the integrated signals do not necessarily have to be integrated.
  • the signals from the optical axis direction can be accumulated in the same phase, thereby ensuring the synchronization of the signals from each dispersed individual.
  • the broadcast individual F1 may be the original observation target, that is, the reflexivity may be obtained, but according to the effect of the present invention, the accumulation point may be different from the observation target. This is an effect of the solution of the present invention that cannot be obtained by the usual retro directive method.
  • the filtering process may be a phase-locked process for extracting a specific frequency component. Since k can be taken freely, the final focused signal can be obtained in another frequency band, which is typically the original signal multiplied to a higher frequency range. Alternatively, each dispersed individual may be received on a different channel in the same frequency band or in a different frequency band.
  • the phase of the signals accumulated and collected in the broadcast individual F1 is the same for the signal from the optical axis direction, regardless of the distance of each dispersed individual from the broadcast individual F1 and the observation target F2. Will be.
  • this result can eliminate and eliminate not only the dependence on x1 (first relative distance) but also the dependence on x2 (second relative distance) at the same time.
  • time synchronization and observation signal synchronization can be achieved in a mobile body, particularly a group of satellites that fly in formation, without going through a wired signal line. This means that it is possible to construct a telescope that integrates and focuses the F1 point of the broadcast individual. You can freely choose k.
  • Local oscillation signal on the broadcast individual F1 And. ⁇ 0 is the initial phase of the local oscillator on the broadcast individual.
  • the reference signal is broadcast from the broadcast individual F1 to each dispersed individual, and is received by each dispersed individual as follows.
  • two observation signals and this signal are combined and passed through a high / low frequency filter or phase synchronization processing (signal processing) And then multiply the frequency by 4/3, after all To get.
  • the phase of the signal gathered in the broadcast individual F1 is independent of the distance (x 2 , x 1 ) from the original observation target F2 and the broadcast individual F1 of each dispersed individual. Therefore, it will be accumulated and focused as a 4-multiplier wave (individual observation result signal).
  • M to n are generally set to form a rational number ratio. Both of the two waves are multiplied by an appropriate rational number and filtered by performing a "product" operation.
  • the frequency k to be finally integrated should be set to avoid the frequency of the observed signal and the frequency of the broadcast reference signal in order to avoid interference, although it is arbitrary.
  • k 4 is set.
  • k When intentionally selecting the deep space band for application to planetary explorers, k should be set at a frequency that fits within the appropriate downlink band.
  • FIG. 8 shows a first configuration example of a communication system applied to earth observation and the like.
  • This first configuration example relates to remote sensing, which is expected to produce results in practical use.
  • the individual 100 in the group of the plurality of dispersed individuals 100, 101, 102 is the broadcast individual F1, and typically, it is an example of irradiating two waves of f1 and f2.
  • This individual 100 (broadcast individual F1) also accumulates signals retransmitted from other dispersed individuals 101 and 102.
  • the individual 100 which is also a dispersed individual, may receive a signal from the observation target F2. In FIG. 8, this reception path is not shown to avoid confusion.
  • the intensity of the signal should be proportional to the received intensity of the signal obtained from the observation target in each dispersed individual. This is because, as shown by (Equation 7), the phase information of the integrated signal depends on the intensity distribution of the observed signal in each dispersed individual. On the contrary, the integration of signals is a factor that requires and complicates the reception intensity of the observed signals in each of the dispersed individuals when estimating the fine structure. Even in earth observation, the main purpose is to acquire superposition information of signals from each microstructure in the observation target area. When integrating signals retransmitted from dispersed individuals such as synthetic aperture radar, it is necessary to measure the integrated signal strength.
  • the observation target F2 is irradiated from the individual 103 and reflects the signal wave to emit two waves of reflected waves f1 and f2. Emit.
  • the signal band to be irradiated is a plurality of frequency bands of two or more in this example.
  • a plurality of reflected waves are transmitted from the observation target F2 in a state where phase information is conveyed as interference signals, and are received by the individuals 100, 101, and 102 of the satellite group, which are dispersed individuals.
  • the individual 103 that irradiates the signal for observation may be the same as the broadcast individual 100 (F1).
  • the broadcast individual 100 creates a reference signal with its own local oscillator or in synchronization with the reflected wave from the observation target, and broadcasts it to other dispersed individuals 101 and 102. ..
  • the observation target F2 is irradiated with two or more signals, one of which may be a signal including a linear spectrum from a signal source arranged in the observation target area in advance. Practically, the form relaxes the demand for the individual to be irradiated. Alternatively, depending on the application, there may be a signal having a linear spectrum having sufficient intensity that can be regarded as a carrier wave, and in that case, irradiation of one wave is sufficient.
  • the above-mentioned configuration example of the communication system can be used for remote sensing targeting the surface of the earth, and leads to an application in which a synthetic aperture radar is configured by a large number of individual satellites in a group without a cable. Radar observations can be realized in real time by free-flying, independent, distributed individual satellites in outer space. However, as described above, it does not require that the integrated processing be performed on the accumulated individuals.
  • this processing can be realized only by one-way communication. That is, it is an independent dispersion method that does not require bidirectional relative position measurement.
  • the processing of each dispersed individual can be performed independently of the processing of other dispersed individuals.
  • the satellites that make up the system can be freely assembled and separated into a group of dispersed individuals, and the participating individuals may be unknown, opening the way for widespread use. If the signal strength distribution of the fine structure is to be obtained from the integrated information, the signal strength of the entire system needs to be standardized, and in reality, the number of participating individuals needs to be known.
  • the dispersed individuals who receive and respond to the observation signal and the reference signal are free to participate and are free to disperse.
  • Many small satellites will be able to participate in or leave the construction of large missions.
  • the weak signal is limited to the signal from the original observation target, etc., and especially in the actual application where the reference signal is emitted from the short-distance broadcast individual F1, the demand for receiver performance is low, and there are restrictions on mountability. few.
  • the communication system of the present invention provides a communication system that serves as an interferometer wirelessly. That is, the broadcast individual F1 that transmits the reference signal transmits the reference signal to the individual (distributed individual) group, and each dispersed individual receives one or more signals of different frequencies from the observation target, and the phase is After performing adjustment processing, both the spatial distance to the broadcast individual F1 that transmits the reference signal from each dispersed individual and the spatial distance to the observation target F2 are offset, and the signal is retransmitted and received by the broadcast individual. Eliminating those effects from the signal.
  • the distance from the broadcast individual F1 which is the reference signal source to each dispersed individual by transmitting a single wave reference signal and receiving signals with different frequencies of one or more from the observation target on each dispersed individual.
  • the effects of both the unknown and the unknown distance from the observed F2 to each dispersed individual are eliminated, and in a direction different from the direction of the observed F2, with a predetermined turnaround frequency. It can be integrated and focused, and a communication system as an interferometer can be configured. Of course, as a special case, it is possible that the direction of accumulation matches the observation target.
  • the signals of the plurality of bands obtained from the observation target may generally be a diffusion spectrum over a set of rational numbers of frequencies.
  • this can be achieved by one-way communication and broadcasting means (broadcasting individual F1), so individual satellites that are dispersed individuals can be freely assembled and separated, and no specific individual identification is required. Therefore, it is advantageous compared to other communication systems.
  • the broadcast individual transmits a synchronization signal for sweeping the ground surface to the irradiated individual, and at the same time, each dispersed individual receives the observation signal.
  • the reception sensitivity of each dispersed individual can be improved.
  • the individual 100 which is also a dispersed individual, also includes receiving the signal from the observation target F2, so it is indicated by a broken line, but this reception is not always necessary in constructing the system.
  • a signal source having one wave may be arranged in the observation target area in advance to secure a signal having a line spectrum having sufficient intensity that can be regarded as a carrier wave.
  • the application of the present invention is not necessarily limited to the application in which each dispersed individual flies freely.
  • the physical position and distance are generally known, but in-phase communication cannot be guaranteed, or the transponders fluctuate from moment to moment. If it is possible, it will be a powerful application example in reality.
  • An example of retro-directed communication of a communication system in which communication data generated on an individual is carried and returned in phase with the marker station is shown. The uncertainty about the marker stations at the positions of the dispersed individuals 101, 102, 103, 104, 105 and 106 is eliminated.
  • FIG. 11 shows, for example, an application in a spacecraft having a film surface structure in which it is difficult to construct one large primary mirror.
  • the group of dispersed individuals 101, 102, 103, 104, 105, 106 on the film surface S is uncertain with respect to the ground station E at the positions of dispersed individuals 101, 102, 103, 104, 105, 106 using this method. This is an example of eliminating the sexuality and functioning as a single large primary mirror.
  • the Ka-band With downlink the earth station can generate signals with the same phase. That is, a retro-directive type antenna can be configured.
  • Tables 1 and 2 shown in FIGS. 18 and 19 list related frequency allocations that are internationally assigned for deep space communications. It can be confirmed that this retro-directive downlink return is actually possible.
  • Application example-2 In the above-mentioned example of the communication system (application example-1), three types of individuals were included: the observation target F2, the broadcast individual F1, and a plurality of dispersed individuals participating in the observation. Next, a case where a target individual is newly introduced and the communication system is composed of four types of individuals will be described.
  • ⁇ be the transmission frequency of the target individual.
  • Each dispersed individual receives signals of two different frequencies from one observation target at different propagation distances.
  • a signal in one or more bands including one or more linear spectra having an intensity that enables reoscillation by phase synchronization on the individual The processing method is the same as in FIG. be.
  • the explanation will be given with specific numbers.
  • the frequency of the signal from the observation target be 2 ⁇
  • the frequency of the signal from the target individual be ⁇ .
  • q ⁇ be the frequency of the reference signal broadcast from the broadcast individual
  • the target individual F2 which is an artificial signal source, is placed in the area of the spatial solid angle to be observed. As a result, interference with the signal from the original observation target can be avoided.
  • ⁇ does not need to take any rational ratio to the frequency of the reference signal transmitted from the broadcast individual.
  • q ⁇ and k ⁇ are used for convenience in order to distinguish between the reference signal and the frequency to be retransmitted.
  • the signal from the observation target expresses the initial phase, which is the observation information, with ⁇ 0. And. Since this initial phase has the effect of changing the optical path length from the fine structure depending on the position on the baseline from the origin of the group, the amount of deviation from the optical axis direction differs for each dispersed individual.
  • a local oscillator independent of the observation target is used. Is assumed to emit the signal of. ⁇ 0 is the initial phase of the transmitter. If this target individual is a point source, ⁇ 0 is common to all dispersed individuals and is fixed. This is natural because the target individual direction is set to the optical axis direction.
  • the frequencies of the two signals in the field of view to be observed shall have a rational number ratio as described in the present invention. In the example here, it is 2: 1.
  • x2A and x2B indicate the true observation target and the distance to the target individual. Both are different.
  • the frequency of the reference signal shall be any real multiple of ⁇ , q times. When this is broadcast and the phase of the target individual signal is subtracted twice, To get.
  • the phases of the second, third, and fifth terms in parentheses are signals that can be shared or broadcast within the group, and are a fixed amount shared among the dispersed individuals.
  • the fifth item is the distance between the observation target and the target satellite, which is irrelevant and common among the dispersed individuals participating in the observation at the same time. After all, the signal returned from each dispersed individual to the accumulated individual is Therefore, the distance x1 between the accumulating broadcast individuals and each dispersed individual is also offset.
  • the observation target frequency and the oscillation frequency of the target individual may be assumed to be an arbitrary rational number ratio. If it is further generalized, it may be a diffusion spectrum formed by a rational number.
  • One of the purposes of providing the signal source of the target individual F2 is to supplement the phase stability of the signal of the observation target itself.
  • the observation target is, for example, a distant galaxy, it is distributed over a wide spectrum, in other words, the phase changes unstable and is distributed.
  • the signal from the observation target from the observation target F2 and from the target individual it is possible to secure a signal having a line spectrum having sufficient intensity that can be regarded as a carrier wave in the direction of the observation target.
  • observation wavelength / baseline length gives the angular resolution of the observation system (communication system)
  • the distance at which the target individual F2 is placed is this (communication, length scale / angular resolution at which the observation system is deployed). It must be the above. Even in a group satellite system in orbit around the earth, the distance to the target individual F2 is, in some cases, well comparable to the distance in the Earth's gravitational sphere.
  • the target individual F2 is not limited to an artificial celestial body. Placing artificial objects far enough away is not easy from a cost perspective. Applications in which the background radio celestial body plays the role of a target individual are promising, especially in communication and observation systems that use dispersed individuals with long baselines, such as intercontinental and global hemispherical scales. It must be a distant radio celestial body. The frequency to be observed and the signal frequency of the radio source need only be a rational ratio, and are not a constraint on observation.
  • FIG. 13 shows a typical configuration example of a communication system composed of four types of individuals including the target individual F2.
  • the broadcast individual 100 (F1) and the dispersed individuals 101 and 102 receive signals from the observation target and the target individual 110, and they are processed as if they were signals from one observation target.
  • a plurality of satellites as a plurality of dispersed individuals 101 and 102 perform astronomical observation.
  • the dispersed individuals may include individuals on the surface of the earth.
  • the individual 100 which is also a dispersed individual, also includes receiving the signal from the observation target F2, so it is indicated by a broken line. This reception is not always necessary to configure the system.
  • the obtained spatial resolution is 10 ⁇ -5 radians. Therefore, in a group satellite observation system (communication system) of the same scale, when the target individual 110 is artificially provided, if the target individual 110 is placed at a distance of 10 ⁇ 5 km or more, the spatial resolution is maintained and the actual object 110 is actually provided. You will be able to build an interferometer that works in time. Of course, it is more advantageous in terms of resolution that the target individual 110 is a radio wave celestial body at infinity. By using the target individual 110 as an artificial satellite or the like, it is possible to expand the degree of freedom in selecting the direction of the observation target. In the 300 GHz band (wavelength 1 mm), a real-time interferometer can be constructed by placing the target at 10 ⁇ 6 km, that is, near the Lagrange point of the Sun-Earth system.
  • FIG. 14 shows a configuration example of a communication system including a target individual applied to the real-time orbit determination of the deep space probe.
  • the dispersed individuals 101 and 102 are a group of stations on the ground 200 that straddle spacecraft or intercontinents. Signals from the deep space probe are received by the observation spacecraft and distributed ground stations 101 and 102.
  • the atomic clock placed on the ground station and the time signal supplied from the navigation satellite are used, and the observation spacecraft and each ground station are used.
  • a stable radio source in the background a radio celestial body, has been used.
  • a reference signal from a stationary or high altitude satellite is used as a means for time synchronization and a reference signal generation means.
  • Those spacecraft are broadcast individuals 100.
  • a broadcast individual it is effective to use satellites that stay at high altitudes with a very long visible time, such as geostationary satellites that can be seen simultaneously from observation spacecraft in a range close to the hemisphere and ground stations 101 and 102.
  • the method Regarding the uncertainties in the positions of the observation spacecraft 101 and 102 of each dispersed individual, the ground station, and the position of the geostationary satellite, as provided by the present invention, a stable radio wave source in the background of the target individual F2, etc.
  • the reference signal is broadcast from the above geostationary or high altitude satellites to the distributed individuals 101, 102 observation spacecraft, and each ground station.
  • Uncertainty is removed in real time from the signal accumulated in the broadcast individual 100, which is also an accumulated individual.
  • the signals received and processed by the distributed individuals 101 and 102 observation spacecraft and each ground station are retransmitted and simultaneously accumulated in the same phase in real time by the above-mentioned stationary or high altitude satellite (broadcast individual 100). .. It is not necessary to integrate the signals from these dispersed individuals.
  • the frequency of the signal retransmitted from each dispersed individual is arbitrary, it is possible to identify and accumulate the signal from each dispersed individual by, for example, frequency identification.
  • the signal from the integrated deep space probe is a point source, so the phase information obtained from each distributed individual directly provides clear one phase difference information.
  • the movement of the observation spacecraft, the ground station group, and the broadcast / accumulated individuals relative to each other due to rotation or revolution will lead to higher resolution.
  • the RA and declination information of the deep space probe can be specified with high resolution.
  • the individual 100 which is also a dispersed individual, also includes receiving the signal from the observation target F2, so it is indicated by a broken line. This reception is not always necessary to configure the system.
  • FIG. 15 shows, as an example of physical observation, a communication system including a target individual applied to astronomical observation on a hemispherical scale.
  • space VLBI observations consisting of stations 101 and 102 on the ground 200 including spacecraft are performed.
  • the method is similar to the method for determining the orbit of the deep space probe in FIG.
  • the target individual F2 should be a radio celestial body at infinity.
  • the obtained observation signals are retransmitted from the terrestrial radio telescopes and space telescopes, which are dispersed individuals 101 and 102, and are collected and collected in the same phase in real time by a stationary or high altitude satellite (broadcast individual 100). be able to.
  • the integrated signals do not need to be integrated.
  • the individual 100 which is also a dispersed individual, also includes receiving the signal from the observation target F2, so it is indicated by a broken line. This reception is not always necessary to configure the system.
  • the effects of the above-mentioned communication system can be directly exerted when spacecraft such as artificial satellites and spacecraft are used as a group.
  • Signal processing can be done independently of the individual positions of the satellites in the group, but to estimate the microstructure of the observation target, the origin of the group, that is, the position on the baseline in the plane perpendicular to the optical axis, that is, the formation Structural management and control is required.
  • the management accuracy may be low, and it is sufficient that the information is maintained at about one digit below the length scale of the group and the information is provided.
  • the dispersed individuals in a group may be distributed over a wide area, and any individual spacecraft such as spacecraft existing on the global scale, that is, on the hemisphere on the ground surface, and in the range around the same hemisphere can participate.
  • a geostationary satellite can be assumed as a useful broadcast individual F2 or an accumulated individual.
  • a geostationary satellite or a satellite having a high altitude at a distant point that can cover the hemisphere for a long time can be assumed as a useful target individual F2.
  • each signal transmitted and received may generally be an electromagnetic wave including light or a sound wave.
  • the present invention is not limited to the above-described embodiments, various examples, modifications thereof, and application examples. Various modifications can be made based on the gist of the present invention, and these are not excluded from the scope of the present invention.
  • the sensitivity of related measuring instruments and signal receiving devices needs to be calibrated. Therefore, if necessary, it should be combined with receiving a signal from another known observation target.
  • the present invention provides a phase adjustment method until the observation result signal is retransmitted and accumulated through each dispersed individual, but it does not propose an integrated process.
  • phase modulation information which is the communication data included in the observation signal is an output, and functions as a means for actually extracting them. In this case, the higher the strength of the received signal, the better, and it is not necessary to measure the strength of the received signal individually.
  • FIG. 16 is an example of a block diagram showing processing on each dispersed individual. The description herein relates to the phase-locked multiplication process portion of this block diagram.
  • applications that measure the strength of the signal received by the system It is assumed that the intensity of the observation signal received by each dispersed individual can be measured. Further, in order to measure the intensity change generated in the communication between the accumulated individual and each dispersed individual, it is assumed that the reception intensity of the reference signal from the broadcast individual and the signal from another broadcast individual can be measured.
  • FIG. 16 shows an example in which signal strength measurement and a variable output amplifier are provided.
  • the observed signal is demodulated, and the signal is placed on the broadcast reference signal and retransmitted.
  • a variable output amplifier is not required for this application, and each distributed individual may be retransmitted at maximum output.
  • the transmission frequency k ⁇ of the return signal can be phase-locked on the integrated individual even if it is multiplied by an arbitrary rational number, so that the return signal from each dispersed individual is frequency-identified and separated.
  • Frequency identification FDMA Frequency-Discriminative Multi-Access
  • code identification CDMA Code-Discriminative Multi-Access
  • the restriction of managing the signal strength retransmitted from each dispersed individual to the integrated individual is released while maintaining the homology, that is, the phase synchronization function, and each dispersed individual can freely select.
  • each dispersed individual shares a common spatial solid angle region to be observed, but when resolving and reconstructing the intensity distribution of the microstructure of the observed object, the direction of the observed object, that is, light from each dispersed individual It is necessary to manage and control the group / formation relative to the origin of the group with respect to the position on the baseline of each dispersed individual in the plane perpendicular to the axial direction.
  • the required accuracy is about an order of magnitude smaller than the baseline length constructed by the dispersed individuals, there is no problem, and only loose position control and acquisition of position information are required.
  • the sensitivity of the baseline length error to the resolution is And in many cases it doesn't matter. This is because the improvement in resolution is obtained by increasing the length of the baseline.
  • FIG. 17 shows an example of one specific processing method for estimating the fine structure of the observation target by identifying by frequency or code without integrating the accumulated signals and obtaining phase information from each dispersed individual.
  • a description will be given using a target individual.
  • the signal obtained from the observation target is Can be assumed.
  • the content of the phase information ⁇ 0m depends on the position on the baseline from the origin of the group of dispersed individuals receiving this signal. That is, the phase of the signal in the direction off the optical axis changes depending on the position on the baseline of the dispersed individual. If the signal transmitted from the target individual is described with the initial phase as zero without losing generality, Is. It is assumed that n and m are rational number ratios.
  • m, i are the distances from the observation target to the dispersed individual i.
  • phase information ⁇ 0 m, i is a function of the position of the dispersed individual i on the baseline.
  • the carrier signal from the target individual Represented by, phase-locked to this, on the dispersed individual i Signal is oscillated.
  • this is multiplied by m / n and the phase processing described in the present invention is performed, the phase information is obtained. Is extracted.
  • the second term is the distance between the observation target and the target individual in the optical axis direction, which is common to all dispersed individuals within a certain observation period.
  • the reference signal of is broadcast.
  • This reference signal is i on the dispersed individual Is received, and using this, the phase adjustment procedure of the present invention is applied to create a signal to be retransmitted to the integrated individual as follows.
  • f () indicates some scaling operation for phase information.
  • the frequency to be retransmitted can be any rational multiple of the received signal frequency, and here it is assumed that the dispersed individual i is retransmitted at the frequency (ki x ⁇ ). By selecting ki, observation results can be identified and accumulated for each dispersed individual.
  • Ji indicates, for example, a modulator of double phase modulation (BPSK: Bi-Phase Shift Keying) with an identification code for each distributed individual, and (code identification: CDMA Code).
  • BPSK Bi-Phase Shift Keying
  • code identification CDMA Code
  • -Discriminative Multi-Access This makes it possible to identify dispersed individuals and collect observation results even if the frequency to be retransmitted is the same.
  • phase information ⁇ 0 m i depends on the position on the baseline from the origin of the group of dispersed individuals receiving this signal, and if the position on the baseline is described as di, the phase information obtained is Satisfy the relationship.
  • the definition of the symbol is described above with respect to (Equation 9). Different dispersed individuals correspond to different di, and if the phase information about them can be measured, the simultaneous equations can be solved to obtain the fine structure ⁇ vector.
  • the second item Is a fixed amount of bias and can be estimated simultaneously by simultaneous equations.
  • the measurement method as an interferometer is not limited to this method, but by reproducing only the phase information without integrating the signals, analog processing related to integration is omitted, and the effects of directivity and distortion of antennas and optical devices are eliminated. can.
  • the present invention proposes to change the stereotype of centralized control so that a large number of dispersed individuals perform independent dispersion processing for that purpose with a certain common purpose. It can be applied in a wide range of applications, from scientific astronomical observations to engineering technologies such as ultra-long-distance communications, and remote sensing observations as industrial technologies. It can be expected to be widely applied in the industrial world.
  • the method of the present invention differs from the method of the prior art in terms of the number of signal bands used and the number of transceivers in the system. The configuration method in this method is simpler and more practical. If the synchronism of a large number of radars is established according to the present invention, it is possible to obtain detailed weather information, etc., which was not possible with a single mirror so far, and the influence on the industrial world is immeasurable.

Abstract

La présente invention comprend: une pluralité d'entités dispersées 101, 102 qui reçoivent sans fil un spectre linéaire qui possède une intensité qui permet une ré-oscillation par synchronisation de phase et un signal d'observation d'une ou plusieurs fréquences à partir d'un objet observé F2; et une entité de diffusion 100 (F1) qui diffuse sans fil un signal de référence prescrit vers la pluralité d'entités dispersées. Chacune des entités dispersées 101, 102 comprend une unité de traitement de signal qui, à partir du signal de référence provenant de l'entité de diffusion 100 (F1) et du signal d'observation reçu en provenance de l'objet observé F2, va générer un signal qui doit être reçu en phase par l'entité de diffusion 100 comme un signal de résultat d'observation d'entité qui ne dépend pas d'une première distance relative entre l'entité dispersée pertinente et l'entité de diffusion 100, ni d'une seconde distance relative entre l'entité dispersée pertinente et l'objet observé F2. Les signaux générés par les unités de traitement de signal sont retransmis sans fil vers l'entité de diffusion, et des informations de phase concernant l'objet observé qui a été identifié par l'entité dispersée sont accumulées.
PCT/JP2020/018478 2020-05-07 2020-05-07 Système de communication et procédé de traitement de signal WO2021224952A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2020/018478 WO2021224952A1 (fr) 2020-05-07 2020-05-07 Système de communication et procédé de traitement de signal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2020/018478 WO2021224952A1 (fr) 2020-05-07 2020-05-07 Système de communication et procédé de traitement de signal

Publications (1)

Publication Number Publication Date
WO2021224952A1 true WO2021224952A1 (fr) 2021-11-11

Family

ID=78467978

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/018478 WO2021224952A1 (fr) 2020-05-07 2020-05-07 Système de communication et procédé de traitement de signal

Country Status (1)

Country Link
WO (1) WO2021224952A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0394185A (ja) * 1989-09-06 1991-04-18 Mitsubishi Electric Corp レーダシステム
WO2010073241A2 (fr) * 2008-12-23 2010-07-01 Elta Systems Ltd. Système de communication rétrodirectif numérique et procédé associé
WO2017141352A1 (fr) * 2016-02-16 2017-08-24 三菱電機株式会社 Dispositif de détection d'objets et dispositif formant capteur
WO2019224894A1 (fr) * 2018-05-22 2019-11-28 合同会社パッチドコニックス Système de communication et procédé de traitement de signal

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0394185A (ja) * 1989-09-06 1991-04-18 Mitsubishi Electric Corp レーダシステム
WO2010073241A2 (fr) * 2008-12-23 2010-07-01 Elta Systems Ltd. Système de communication rétrodirectif numérique et procédé associé
WO2017141352A1 (fr) * 2016-02-16 2017-08-24 三菱電機株式会社 Dispositif de détection d'objets et dispositif formant capteur
WO2019224894A1 (fr) * 2018-05-22 2019-11-28 合同会社パッチドコニックス Système de communication et procédé de traitement de signal

Similar Documents

Publication Publication Date Title
US10048382B2 (en) Cellular interferometer for continuous Earth remote observation (CICERO) satellite
Nanzer et al. Distributed phased arrays: Challenges and recent advances
Warnick et al. Phased arrays for radio astronomy, remote sensing, and satellite communications
Nozette et al. The Lunar Reconnaissance Orbiter miniature radio frequency (Mini-RF) technology demonstration
Rajan et al. Space-based aperture array for ultra-long wavelength radio astronomy
CN104884350B (zh) 诸如为了定位地球上的干扰源等的用于获得与从地球发射的电磁能量有关的信息的设备、系统和方法
US10684347B2 (en) Systems and methods for measuring terrestrial spectrum from space
Nie et al. Channel modeling and analysis of inter-small-satellite links in terahertz band space networks
US8102313B2 (en) Retroreflecting transponder
CN109188434B (zh) 基于调频连续波体制的sar系统及其处理方法
US11249183B2 (en) Motion extended array synthesis for use in high resolution imaging applications
Cecconi et al. NOIRE study report: towards a low frequency radio interferometer in space
US10574338B1 (en) Systems for surveillance using airborne platforms as receiving platforms for bistatic radars
Zurita et al. Towards a SMOS operational mission: SMOSOps-hexagonal
RU2700166C1 (ru) Способ глобальной активно-пассивной многопозиционной спутниковой радиолокации земной поверхности и околоземного пространства и устройство для его осуществления
Zuo Bistatic synthetic aperture radar using GNSS as transmitters of opportunity
Marrero et al. Architectures and synchronization techniques for distributed satellite systems: A survey
WO2019224894A1 (fr) Système de communication et procédé de traitement de signal
Valente et al. The sardinia space communication asset: Performance of the sardinia deep space antenna x-band downlink capability
Garrison et al. Signals of opportunity: enabling new science outside of protected bands
Yin et al. Integrated Sensing and Communications Enabled Low Earth Orbit Satellite Systems
WO2021224952A1 (fr) Système de communication et procédé de traitement de signal
Babuscia et al. Development of cooperative communication techniques for a network of small satellites and CubeSats in deep space: the SOLARA/SARA test case
Wang et al. Antenna directing synchronization for bistatic synthetic aperture radar systems
TWI584663B (zh) 透過無人機的通訊系統

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20934321

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20934321

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP