Communication Systems

Abstract

To provide a communication system capable of transmitting jamming radio waves corresponding to radio waves with a wide bandwidth to wireless devices to be monitored.SOLUTION: A communication system includes a wideband receiver 40 that can receive radio waves with a wide bandwidth, including bands of multiple monitored radio waves, and output reception status data from the received monitored radio waves; a plurality of transmitting devices 60 that transmit radio waves for jamming to a radio device 10 that generates the received monitored radio waves; and a monitoring server 45 that inputs the reception status data from the wideband receiver 40, causes the plurality of transmitting devices 60 to transmit at different bands to make the radio waves for jamming against the radio device 10 wideband to match the bands of the radio waves generated by the radio device 10, and thereby controls spatial synthesis of the radio waves.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a communication system for jamming radio waves of a wireless device to be monitored, and more particularly to a communication system that realizes jamming of radio waves over a wide band. [Background technology]

[0002] [Prior Art] In conventional communication systems, a wireless device may combine signals using an amplifier to obtain a desired output power and transmit the required signal power. Furthermore, transmitting devices having a function for jamming communications are in practical use. A transmitting device with a communication jamming function monitors, for example, radio waves from a wireless device that is the source of wireless communication carried out within a monitored area, and generates jamming radio waves.

[0003] [Conventional first communication system: Figure 6] Next, a first conventional communication system will be described with reference to Fig. 6. Fig. 6 is a schematic diagram of the configuration of the first conventional communication system. The first conventional communication system includes a wireless device 10 for a plurality of monitoring targets, a monitoring receiver 20, a transmitting device 30, and a monitoring server 24, as shown in FIG.

[0004] A monitoring receiver 20 in a conventional first communication system receives radio waves from known monitored wireless devices 10a-10d and an unknown wireless device 10e (sometimes simply referred to as "wireless device 10"), and outputs information about the received radio waves to a monitoring server 24. The monitoring server 24 estimates the frequency band, direction of arrival, position of the radio wave, etc., of the radio wave based on the information of the received radio wave input from the monitoring receiver 20, and controls the transmitting device 30 to calculate the distance and range for jamming the radio wave toward the radio device 10 and transmit the jamming radio wave. The transmitting device 30 transmits jamming radio waves from a transmitting antenna 31 to an area where the wireless device 10 exists, based on control information from the monitoring server 24 .

[0005] In the first conventional communication system, in order to jam communications of a plurality of wireless devices, the same number of transmitting devices 30 as the number of wireless devices 10 to be jammed were required. This meant that the number of wireless devices 10 that could be jammed was limited, making the system inefficient and unable to realize a simple, low-cost configuration.

[0006] [Conventional second communication system: Figure 7] Next, a second conventional communication system will be described with reference to Fig. 7. Fig. 7 is a schematic diagram showing the configuration of the second conventional communication system. The second conventional communication system is almost the same as the first conventional communication system, as shown in FIG. 7, except that the transmitting device 30 is equipped with multiple transmitting antennas 31a, 31b, and the monitoring server 24 controls the transmitting antennas 31a, 31b to transmit different jamming radio waves. In FIG. 7, the transmitting device 30 transmits different jamming radio waves to the wireless device 10a and the wireless device 10c.

[0007] Moreover, the second conventional communication system solves the problems of the first conventional communication system and is capable of transmitting jamming radio waves to a plurality of radio devices 10a, 10c to be jammed, using a plurality of transmitting antennas 31a, 31b. However, in the conventional second communication system, a single transmitting device 30 outputs jamming radio waves alternately from multiple transmitting antennas 31a, 31b, so that jamming radio waves cannot be transmitted to multiple wireless devices 10 simultaneously, and it is not suitable for instantaneously jamming each wireless device 10.

[0008] [Conventional transmitter: Figure 8] Next, a conventional transmitting device will be described with reference to Fig. 8. Fig. 8 is a schematic diagram showing the configuration of a conventional transmitting device. As shown in FIG. 8, the conventional transmitting device 30 includes an external interface section (external IF) 30a and interfering transmission amplifiers 30b-1 to 30b-N, and transmits interfering radio waves from a single transmitting antenna 31 by combining the power from these interfering transmission amplifiers 30b-1 to 30b-N. The conventional transmitting device 30 realizes the above configuration in a single device, which makes the device large and heavy.

[0009] The jamming transmission amplifier has a variable attenuator (variable ATT) 301, a variable phase shifter 302, a local oscillator 303, a mixer 304, an amplifier 305, and a bandpass filter (BPF) 306, and outputs the power of the desired jamming radio waves to the shared transmitting antenna 31.

[0010] [Related Technology] As a related prior art, there is a "communication system" disclosed in Japanese Patent Application Laid-Open No. 2002-232393 (Patent Document 1). Patent Document 1 discloses a communication method that monitors the status of interference waves in the frequency band used for data communication before data communication, stores the presence or absence of interference waves, and uses a frequency according to the results to avoid or cancel the interference waves, thereby preventing a decrease in information communication speed. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] JP 2002-232393 A Summary of the Invention [Problem to be solved by the invention]

[0012] However, in the conventional first and second communication systems, jamming radio waves of a specific frequency are transmitted based on data collected by a monitoring receiving device, so when the wireless device to be monitored transmits wideband radio waves, there was a problem that the systems were not able to handle the wideband radio waves.

[0013] Incidentally, Patent Document 1 does not disclose a configuration for transmitting jamming radio waves in response to wideband radio waves to a wireless device to be monitored.

[0014] The present invention has been made in view of the above circumstances, and has an object to provide a communication system capable of transmitting jamming radio waves corresponding to wideband radio waves to a wireless device to be monitored. [Means for solving the problem]

[0015] The present invention, which aims to solve the problems of the above-mentioned conventional examples, is a communication system for jamming radio waves of a monitored object, comprising: a receiver capable of receiving wideband radio waves including the bands of the radio waves of multiple monitored objects and outputting data on the reception status from the received radio waves of the monitored objects; a plurality of transmitting devices that transmit jamming radio waves to a wireless device that generates the received radio waves of the monitored objects; and a control device that inputs the reception status data from the receiver, causes the multiple transmitting devices to transmit jamming radio waves in different bands to match the band of the radio waves generated by the wireless device, making the jamming radio waves for the wireless device wideband, and controls the radio waves from the multiple transmitting devices to be spatially combined.

[0016] The present invention is characterized in that in the above communication system, a plurality of receivers connected to the control device are used and installed in a plurality of areas.

[0017] The present invention is characterized in that in the above communication system, the control device performs control to change the band of radio waves transmitted from the multiple transmitting devices in response to a change in the band of radio waves generated by the wireless devices.

[0018] The present invention is characterized in that in the above communication system, the control device divides a plurality of transmitting devices, which transmit jamming radio waves to a plurality of wireless devices, into groups.

[0019] The present invention is a communication system for jamming radio waves of a monitored object, characterized in that it comprises a receiver capable of receiving wideband radio waves including the bands of the radio waves of multiple monitored objects and outputting data on the reception status from the received radio waves of the monitored objects, a plurality of transmitting devices that transmit jamming radio waves corresponding to each of the wireless devices that generate the received radio waves of the monitored objects, and a control device that inputs the reception status data from the receiver and controls the transmission of jamming radio waves from each of the corresponding transmitting devices to each of the wireless devices in accordance with the band of the radio waves generated by each wireless device.

[0020] The present invention is characterized in that in the above communication system, a plurality of receivers connected to the control device are used and installed in a plurality of areas.

[0021] The present invention is characterized in that in the above communication system, the control device performs control to change the band of radio waves transmitted from the multiple transmitting devices in response to a change in the band of radio waves generated by the wireless devices. Effect of the Invention

[0022] According to the present invention, a communications system is provided in which a receiver is capable of receiving wideband radio waves including the bands of the radio waves of multiple monitored objects, and outputs data on the reception status from the received radio waves of the monitored objects, a plurality of transmitting devices transmit jamming radio waves to the wireless devices that generate the received radio waves of the monitored objects, and a control device inputs the reception status data from the receiver and causes the plurality of transmitting devices to transmit jamming radio waves in different bands to match the band of the radio waves generated by the wireless devices so that the jamming radio waves for the wireless devices are wideband, and controls the radio waves from the plurality of transmitting devices to be spatially combined, thereby achieving the effect of transmitting jamming radio waves corresponding to wideband radio waves toward the wireless devices to be monitored. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic diagram illustrating the configuration of a first communication system. [Diagram 2] FIG. 11 is a schematic diagram of a second communication system. [Diagram 3]FIG. 11 is a schematic diagram of a third communication system. [Figure 4] FIG. 13 is a schematic diagram of the configuration of a fourth communication system. [Diagram 5] FIG. 2 is a schematic diagram of the configuration of the present transmitting device. [Figure 6] FIG. 1 is a schematic diagram illustrating the configuration of a first conventional communication system. [Figure 7] FIG. 11 is a schematic diagram illustrating the configuration of a second conventional communication system. [Figure 8] FIG. 1 is a schematic diagram illustrating the configuration of a conventional transmitting device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. [Outline of the embodiment] A communication system (this communication system) according to an embodiment of the present invention is capable of receiving wideband radio waves including the bands of the radio waves of multiple monitored objects and has a receiver that outputs reception status data from the received radio waves of the monitored objects, a plurality of transmitting devices that transmit jamming radio waves to the wireless devices that generate the received radio waves of the monitored objects, and a monitoring server that inputs the reception status data from the receiver, causes the multiple transmitting devices to transmit jamming radio waves in different bands to match the band of the radio waves generated by the wireless devices so that the jamming radio waves for the wireless devices are wideband, and controls the radio waves from the multiple transmitting devices to be spatially combined, and is capable of transmitting jamming radio waves corresponding to wideband radio waves toward the wireless devices to be monitored. This communication system is realized by the following four embodiments.

[0025] [First communication system: Figure 1] The first communication system in the present communication system will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of the configuration of the first communication system. As shown in FIG. 1, the first communication system includes a broadband monitoring receiver (broadband receiver) 40, a monitoring server 45, a plurality of transmitting devices 60a to 60e, and a plurality of transmitting antennas 61a to 61e. The transmitting antennas 61a to 61e are connected to the transmitting devices 60a to 60e, respectively. Although five transmitting devices 60a to 60e (sometimes simply referred to as "transmitting devices 60") and five transmitting antennas 61a to 61e (sometimes simply referred to as "transmitting antennas 61") are shown in FIG. 1, the number of these devices may be any number.

[0026] In the first communication system, jamming radio waves are generated from one transmitting device 30 in the conventional communication system, but are distributed to multiple transmitting devices 30 to reduce the output level. However, the reduced output level is strengthened by spatial synthesis of jamming radio waves from multiple transmitting devices 60. The transmission spectrum waveform of jamming radio waves is easier to form when the output level is low.

[0027] [Wideband monitoring receiver 40] The broadband monitoring receiver 40 is capable of receiving broadband radio waves, and receives radio waves from known wireless devices 10a to 10d as well as unknown wireless device 10e. The broadband monitoring receiver 40 outputs information about the received radio waves to a monitoring server 45.

[0028] [Monitoring Server 45] The monitoring server 45 is a control device that estimates the frequency band, direction of arrival, position information of the wireless device 10, etc. of the received radio waves input from the wideband monitoring receiver 40, and controls the transmission of wideband jamming radio waves to the transmitting device 60. A method of generating wideband jamming radio waves will be described later.

[0029] In addition, when the monitoring server 45 determines from the information of the received radio waves from the wideband receiver 40 that the monitored wireless device 10 has changed the transmission frequency band, it controls the transmitting device 60 to shift the frequency band of the jamming radio waves to follow the changed frequency band and transmit the jamming radio waves.

[0030] [Transmitting device 60] The multiple transmitting devices 60 receive control information for generating jamming radio waves from the monitoring server 45, and each transmitting device 60 generates jamming radio waves of different bands by modulating them. The jamming radio waves to be transmitted are generated so that they have the same amplitude and zero phase difference at the target point.

[0031] Jamming radio waves of the same band may be generated, but although it will not be a wideband wave, the jamming radio waves will overlap at the target point and the power will be a multiple of the number of transmitting devices 60. Furthermore, jamming signals in different bands may partially overlap. Furthermore, the width of the wide band is determined by control information from the monitoring server 45, and the width of the wide band is not fixed, but can be varied according to the state of the radio waves to be monitored.

[0032] [Transmitting antenna 61] The multiple transmitting antennas 61 output the transmission power output from the transmitting device 60 connected thereto into the space of the area to be monitored. In Fig. 1, all the transmitting antennas 61 simultaneously transmit jamming signals toward one wireless device 10a. If the jamming signals transmitted from the transmitting antennas 61 are in different bands, the overall jamming signal that is spatially combined will be in a wide band.

[0033] The first communication system is characterized in that it includes a plurality of transmitting devices 60, and transmits wideband jamming radio waves from a corresponding plurality of transmitting antennas 61 simultaneously to a specific wireless device 10a (specific area). Here, to achieve transmission of jamming radio waves over a wide band, jamming radio waves in frequency band F1 are transmitted from a specific transmitting antenna 61a, while jamming radio waves in frequency band F1-f (lower frequency band F1 by f) are transmitted from another transmitting antenna 61b, and jamming radio waves in frequency band F1+f (higher frequency band F1 by f) are transmitted from another transmitting antenna 61c, and these are spatially combined to transmit jamming radio waves over a wide band (frequency bands F1-f, F1, F1+f).

[0034] [Second communication system: Figure 2] The second communication system in this communication system will be described with reference to Fig. 2. Fig. 2 is a schematic diagram showing the configuration of the second communication system. The second communication system is basically similar to the first communication system, as shown in FIG. 2, but whereas the first communication system transmits jamming radio waves from all transmitting antennas 61 targeting a single wireless device 10a, in the second communication system, multiple transmitting devices 60 are grouped, and multiple transmitting antennas 61 within the group transmit jamming radio waves to a specific wireless device 10.

[0035] Specifically, in FIG. 2, transmitting antennas 61a, 61b, and 61c connected to transmitting devices 60a, 60b, and 60c transmit jamming radio waves to wireless device 10a, and transmitting antennas 61d and 61e connected to transmitting devices 60d and 60e transmit jamming radio waves to wireless device 10c. In the second communication system, the effect of spatial synthesis is smaller, but since jamming radio waves can be transmitted to multiple wireless devices 10, the transmission efficiency is improved.

[0036] [Third communication system: Figure 3] The third communication system in the present communication system will be described with reference to Fig. 3. Fig. 3 is a schematic diagram of the configuration of the third communication system. As shown in FIG. 3, the third communication system has a configuration similar to the first and second communication systems, but multiple transmitting devices 60 are assigned to individual wireless devices 10, and jamming radio waves are transmitted in groups as the smallest unit.

[0037] Specifically, in FIG. 3, transmitting antenna 61a connected to transmitting device 60a transmits jamming radio waves to wireless device 10a, transmitting antenna 61b connected to transmitting device 60b transmits jamming radio waves to wireless device 10b, transmitting antenna 61c connected to transmitting device 60c transmits jamming radio waves to wireless device 10c, transmitting antenna 61d connected to transmitting device 60d transmits jamming radio waves to wireless device 10d, and transmitting antenna 61e connected to transmitting device 60e transmits jamming radio waves to wireless device 10e.

[0038] However, the third communication system does not support wideband because spatial synthesis is not performed, but under the control of the monitoring server 45, the transmitting antennas 61 work together to transmit jamming radio waves in a detailed manner to each wireless device 10.

[0039] [Fourth communication system: Figure 4] A fourth communication system in the present communication system will be described with reference to Fig. 4. Fig. 4 is a schematic diagram showing the configuration of the fourth communication system. As shown in FIG. 4, the fourth communication system is based on the second communication system and has a plurality of installed receiving devices 70 arranged in a mesh pattern within a monitored area. Radio wave information of the wireless devices 10 received by the plurality of installed receiving devices 70 is transmitted via wired or wireless communication to a monitoring server 45. The monitoring server 45 reports the radio wave conditions of the wireless devices 10 in the monitored area and controls the transmission of jamming radio waves to the wireless devices 10. It should be noted that the fourth communication system may be based on the first and third communication systems instead of the second communication system.

[0040] In addition, in the fourth communication system, a plurality of installed receiving devices 70 arranged in a mesh pattern may be equipped with transmitting devices 60 and transmitting antennas 61, and the monitoring server 45 may control the transmitting of jamming radio waves from the installed locations.

[0041] [Transmitting device of this communication system: Figure 5] The transmitting device of this communication system (this transmitting device) will be described with reference to Fig. 5. Fig. 5 is a schematic diagram showing the configuration of this transmitting device. 5, this transmitting device includes an external interface unit (external IF) 60a and interfering transmission amplifiers 60b-1 to 60b-N (hereinafter referred to as interfering transmission amplifiers 60b), and transmits interfering radio waves from transmitting antennas 61a to 61N connected to each of the interfering transmission amplifiers 60b by combining their powers. Here, the directivity of the multiple transmitting antennas 61 is controlled by the monitoring server 45. Since the horizontally arranged configuration of each transmitter 60 and transmitting antenna 61, excluding the external IF 60a in this transmitter, can distribute the transmitters 60, making it possible to reduce the size and weight.

[0042] The jamming transmission amplifier 60b of this transmitting device has a variable attenuator (variable ATT) 601 that controls the amplitude of the baseband signal, a variable phase shifter 602 that controls the phase, a local oscillator 603 for modulation, a mixer 604 that combines the baseband signal with the oscillation signal of the local oscillator 603, an amplifier 605, and a bandpass filter (BPF) 606, and outputs the power of the desired jamming radio waves to each transmitting antenna 61.

[0043] As an example of an application of this communication system, it can be used to counter fraudulent bank transfers by generating jamming signals for mobile phones near ATMs.

[0044] [Effects of the embodiment] According to this communication system, the broadband receiver 40 is capable of receiving broadband radio waves including the bands of the radio waves of multiple monitored objects, and outputs data on the reception status from the received radio waves of the monitored objects, and the multiple transmitting devices 60 transmit jamming radio waves to the wireless devices 10 that generate the received radio waves of the monitored objects, and the monitoring server 45 inputs the reception status data from the broadband receiver 40 and controls the multiple transmitting devices 60 and transmitting antennas 61 to transmit in different bands the jamming radio waves for the wireless devices 10 so as to match the band of the radio waves generated by the wireless devices 10, and controls the radio waves from the multiple transmitting antennas 61 to be spatially combined, thereby achieving the effect of transmitting jamming radio waves corresponding to the wideband radio waves toward the wireless devices 10 to be monitored. [Industrial Applicability]

[0045] The present invention is suitable for a communication system capable of transmitting jamming radio waves corresponding to wideband radio waves to a wireless device to be monitored. [Explanation of symbols]

[0046] 10...wireless device, 20...monitoring receiver, 24...monitoring server, 30...transmitting device, 31...transmitting antenna, 40...wideband receiver, 45...monitoring server, 60...transmitting device, 61...transmitting antenna, 70...installed receiving device, 30a, 60a...external interface unit, 30b, 60b...jamming transmission amplifier, 301, 601...variable ATT, 302, 602...variable phase shifter, 303, 603...local oscillator, 304, 604...mixer, 305, 605...amplifier, 306, 606...BPF

Claims

1. A communication system for jamming radio waves of a monitored object, comprising: a receiver capable of receiving a wideband radio wave including the bands of radio waves of a plurality of monitoring targets and outputting data on the reception status of the received monitoring targets' radio waves; a plurality of transmitting devices that transmit jamming radio waves to the wireless devices that generate the received radio waves to be monitored; A control device that inputs data on reception conditions from the receiver, controls the multiple transmitting devices to transmit in different bands so that the jamming radio waves for the wireless device are wideband to match the band of the radio waves generated by the wireless device, and controls the spatial synthesis of the radio waves from the multiple transmitting devices.

2. 2. The communication system according to claim 1, wherein a plurality of receivers connected to said control device are used and installed in a plurality of areas.

3. 3. The communication system according to claim 1, wherein the control device performs control to change the band of radio waves transmitted from the plurality of transmitting devices in response to a change in the band of radio waves generated by the wireless device.

4. 3. The communication system according to claim 1, wherein said control device divides a plurality of transmitting devices that transmit jamming radio waves to a plurality of wireless devices into groups.

5. A communication system for jamming radio waves of a monitored object, comprising: a receiver capable of receiving a wideband radio wave including the bands of radio waves of a plurality of monitoring targets and outputting data on the reception status of the received monitoring targets' radio waves; a plurality of transmitting devices each transmitting a jamming radio wave to each of the wireless devices that generate the received radio waves to be monitored; A communication system comprising: a control device which inputs reception status data from the receiver and controls the transmission of jamming radio waves from each of the corresponding multiple transmitting devices in accordance with the band of radio waves generated by each of the wireless devices.

6. 6. The communication system according to claim 5, wherein a plurality of receivers connected to said control device are used and installed in a plurality of areas.

7. 7. The communication system according to claim 5, wherein the control device performs control to change the band of radio waves transmitted from the plurality of transmitting devices in response to a change in the band of radio waves generated by the wireless device.

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