CN104076368A - GPS anti-interference antenna technology - Google Patents
GPS anti-interference antenna technology Download PDFInfo
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- CN104076368A CN104076368A CN201410292998.7A CN201410292998A CN104076368A CN 104076368 A CN104076368 A CN 104076368A CN 201410292998 A CN201410292998 A CN 201410292998A CN 104076368 A CN104076368 A CN 104076368A
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- 238000012545 processing Methods 0.000 claims abstract description 15
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- 230000010355 oscillation Effects 0.000 claims description 9
- 238000010586 diagram Methods 0.000 claims description 4
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- 230000003211 malignant effect Effects 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/21—Interference related issues ; Issues related to cross-correlation, spoofing or other methods of denial of service
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- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
- Position Fixing By Use Of Radio Waves (AREA)
Abstract
The invention provides a GPS anti-interference antenna which comprises an antenna array, a radio frequency front end module, an analog-digital conversion module, an adaptive processing module and a beam forming network. The antenna array comprises N antenna array elements, N is larger than or equal to four and smaller than or equal to 16, the space between adjacent array elements is half of center frequency wave length of received signals, and a power inversion algorithm is built in the antenna array. The radio frequency front end module comprises N radio frequency front ends, each radio frequency front end comprises a first band-pass filter, an amplifier, a mixer, an RF local oscillator generator, a second band-pass filter and an intermediate frequency amplifier, wherein the first band-pass filters, the amplifiers, the mixers, the second band-pass filters and the intermediate frequency amplifiers are connected in sequence, and the RF local oscillator generators are connected with the mixers and input local oscillating signals. The GPS anti-interference antenna can effectively eliminate strong interference signals, receive useful signals, and achieve signal receiving in harsh electromagnetic environments.
Description
Technical Field
The invention relates to the technical field of satellite navigation and positioning, in particular to a GPS anti-interference antenna technology.
Background
Satellite navigation positioning technology has great value in both military and commercial applications. The navigation positioning satellite system sends high-precision, all-time and all-weather navigation, positioning and time service information, which is an information resource shared by military and civil users on sea, land and air, and who has the technology and the capability takes the initiative in military affairs, diplomatic affairs and economy. Therefore, extensive research is conducted in various countries on obtaining more accurate satellite navigation information and preventing other parties from obtaining the satellite navigation information, and a satellite navigation system interference technology and an anti-interference technology which are born along with the research become hot spots.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides the GPS anti-interference antenna which can effectively eliminate strong interference signals, receive useful signals and solve the problem of signal reception in a severe electromagnetic environment.
The invention provides a GPS anti-interference antenna, comprising: the system comprises an antenna array, a radio frequency front-end module, an analog-to-digital conversion module, a self-adaptive processing module and a beam forming network; wherein,
the antenna array comprises N antenna elements, wherein N is more than or equal to 4 and less than or equal to 16, 1/2 of the central frequency wavelength of a received signal is obtained by the distance between adjacent antenna elements, and a power inversion algorithm is built in the antenna array;
the radio frequency front end module comprises N radio frequency front ends, and each radio frequency front end comprises a first band-pass filter, an amplifier, a frequency mixer, an RF local oscillation generator, a second band-pass filter and an intermediate frequency amplifier, wherein the first band-pass filter, the amplifier, the frequency mixer, the second band-pass filter and the intermediate frequency amplifier are sequentially connected, and the RF local oscillation generator is connected with the frequency mixer to input local oscillation signals;
the analog-to-digital converter comprises N analog-to-digital converters, wherein the downlink of the analog-to-digital converter converts an analog signal into a digital signal, and the uplink of the analog-to-digital converter converts the digital signal into an analog signal;
the adaptive processing module comprises N adaptive processors, the adaptive processors are internally provided with adaptive algorithms, and weight values are generated according to adaptive spatial filters or beam forming algorithms and estimated incoming wave directions;
a beam forming network for performing a dynamic adaptive weighting process to generate a desired adaptive beam;
the antenna array elements, the radio frequency front ends, the analog-to-digital converters and the adaptive processors are in one-to-one correspondence, the input end of a first band-pass filter in the radio frequency front end is connected with the antenna array elements corresponding to the antenna array elements to receive signals, the output end of an intermediate frequency amplifier is connected with the analog-to-digital converters corresponding to the antenna array elements to output signals, the analog-to-digital converters are connected with the adaptive processors corresponding to the analog-to-digital converters, and each adaptive processor is connected to a beam forming network;
in the working state, the antenna utilizes the self-adaptive beam forming technology to form antenna radiation directional diagram null in the arrival direction of the interference signal, and forms a null point in the direction of the interference wave to shield the interference signal.
Preferably, the antenna array is a four-element circular antenna array.
The invention adopts the self-adaptive intelligent antenna technology, is convenient to realize, has good anti-interference effect, can effectively inhibit unintentional or intentional electronic interference of enemies by only adding a plurality of GPS (Global Positioning System) receiving antennas and a self-adaptive antenna zero-setting digital signal processing board and making small changes on the connection of a mechanical structure and an electric appliance, ensures the normal resolving of navigation data of a civil GPS receiver, improves the fighting capacity of the GPS civil receiver for adapting to the severe electromagnetic environment of modern war, can support cross-sea fighting, and has great military significance for fighting in key and local areas. Meanwhile, the system can also be suitable for various civil occasions with interference, and has important social and economic significance. The invention is designed with a radio frequency front end to filter and amplify the antenna signal, thereby providing convenience for subsequent processing.
Drawings
FIG. 1 is a schematic diagram of a four-element circular antenna array;
fig. 2 is a diagram of a radio frequency front end structure.
Detailed Description
Referring to fig. 1 and fig. 2, the GPS anti-jamming antenna according to the present embodiment includes: the system comprises an antenna array, a radio frequency front-end module, an analog-to-digital conversion module, a self-adaptive processing module and a beam forming network.
The antenna array is a quaternary circular antenna array based on a power inversion algorithm and comprises four antenna array elements, the signal receiving coverage area of the four antenna array elements is circular, 360-degree omnibearing signal receiving is achieved by using the minimum number of the antenna array elements, the design is reasonable, the consumption is low, and the signal receiving is complete and repeated. The distance between adjacent array elements in the antenna array is 1/2 of the wavelength of the center frequency of the received signal, so that the omission of signal reception is avoided.
The power inversion algorithm suppresses both the received useful signals and the received interference signals, the beam pattern generates nulls in the directions of the useful signals and the interference signals, and the stronger the signal is, the deeper the corresponding nulls are, the more ideal the elimination of the strong interference signals is, so the array is very effective for the reception of the weak signals.
The radio frequency front end module comprises four radio frequency front ends. The radio frequency front end comprises a first band-pass filter, an amplifier, a frequency mixer, an RF local oscillation generator, a second band-pass filter and an intermediate frequency amplifier, wherein the first band-pass filter, the amplifier, the frequency mixer, the second band-pass filter and the intermediate frequency amplifier are sequentially connected, and the RF local oscillation generator is connected with the frequency mixer to input local oscillation signals.
The Analog-to-Digital converter comprises four Analog-to-Digital converters (A/D), wherein the downlink of the Analog-to-Digital converters converts Analog signals into Digital signals for convenient signal processing, and the uplink of the Analog-to-Digital converters converts the Digital signals into Analog signals for convenient signal transmission.
And the adaptive processing module comprises four adaptive processors W1, W2, W3 and W4. The self-adaptive processor is internally provided with a self-adaptive algorithm, and generates a weight according to a self-adaptive spatial filter or a beam forming algorithm and the estimated incoming wave direction.
And a beam forming network for performing a dynamic adaptive weighting process to generate a desired adaptive beam.
The antenna in this embodiment has a simple structure and is easy to implement, where four antenna elements, four radio frequency front ends, four analog-to-digital converters, and four adaptive processors correspond to each other one by one, an input end of a first band-pass filter in the radio frequency front end is connected to a corresponding antenna element receiving signal, an output end of an intermediate frequency amplifier is connected to a corresponding analog-to-digital converter output signal, the analog-to-digital converters are connected to corresponding adaptive processors, and each adaptive processor is connected to a beam forming network.
The antenna array element receives signals, the radio frequency front end filters and amplifies the received signals to lay a foundation for subsequent processing, the analog-to-digital converter converts the received analog signals into digital signals to facilitate processing, the adaptive processors respectively carry out weighting on the received signals, and the beam forming network carries out comprehensive processing on the weighted signals to generate expected adaptive beams, so that interference signals are eliminated, and useful signals are received.
In this embodiment, the antenna uses the adaptive beam forming technology to form an antenna radiation pattern null in the arrival direction of the interference signal, and forms a null in the direction of the interference wave, thereby shielding the interference signal. The antenna has the advantages of being capable of completely independent operation without the support of other external equipment and without any modification of software in the receiver.
In specific implementation, the antenna array may include N antenna elements, where 4 ≦ N ≦ 16, 1/2 of the center frequency wavelength of the received signal is obtained between adjacent antenna elements, the radio frequency front end module includes N radio frequency front ends, the analog-to-digital converter includes N analog-to-digital converters, the adaptive processing module includes N adaptive processors, the N antenna elements, the N radio frequency front ends, the N analog-to-digital converters, and the N adaptive processors are in one-to-one correspondence, an input end of a first bandpass filter in the radio frequency front end is connected to a corresponding antenna element, an output end of the if amplifier is connected to a corresponding analog-to-digital converter, the analog-to-digital converter is connected to a corresponding adaptive processor, and each adaptive processor is connected to the beam forming network.
Because the GPS satellite signal is rather weak (about-160 dBW) when reaching the terrestrial user receiver, which is about 30dB lower than the thermal noise of the receiver, the weak interference may cause the GPS receiver to be unstable, especially the artificial malignant interference, which may cause the system accuracy to decrease or even fail to work normally and lose the navigation capability, and the GPS anti-interference technology has become a critical problem that the satellite navigation receiver is urgently required to solve. The interference of the GPS receiver is mainly embodied as frequency interference and power interference, and therefore, a design method for improving the anti-interference performance of the GPS receiver is to improve the signal receiving power and the filtering technology.
The GPS anti-interference antenna technology provided in the above embodiment adopts a self-adaptive intelligent antenna technology, is convenient to realize and has good anti-interference effect, and only a plurality of GPS receiving antennas and a self-adaptive antenna zero-setting digital signal processing board need to be added, and small changes are made on the connection of a mechanical structure and an electrical appliance, so that unintentional or intentional electronic interference of enemies can be effectively inhibited, the normal resolving of navigation data of a civil GPS receiver is ensured, the fighting capacity of the civil GPS receiver for adapting to the severe electromagnetic environment of modern war is improved, cross-sea fighting can be supported, and great military significance is realized on the fighting of key and local areas. Meanwhile, the system can also be suitable for various civil occasions with interference, and has important social and economic significance.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (2)
1. A GPS jamming antenna, comprising: the system comprises an antenna array, a radio frequency front-end module, an analog-to-digital conversion module, a self-adaptive processing module and a beam forming network; wherein,
the antenna array comprises N antenna elements, wherein N is more than or equal to 4 and less than or equal to 16, 1/2 of the central frequency wavelength of a received signal is obtained by the distance between adjacent antenna elements, and a power inversion algorithm is built in the antenna array;
the radio frequency front end module comprises N radio frequency front ends, and each radio frequency front end comprises a first band-pass filter, an amplifier, a frequency mixer, an RF local oscillation generator, a second band-pass filter and an intermediate frequency amplifier, wherein the first band-pass filter, the amplifier, the frequency mixer, the second band-pass filter and the intermediate frequency amplifier are sequentially connected, and the RF local oscillation generator is connected with the frequency mixer to input local oscillation signals;
the analog-to-digital converter comprises N analog-to-digital converters, wherein the downlink of the analog-to-digital converter converts an analog signal into a digital signal, and the uplink of the analog-to-digital converter converts the digital signal into an analog signal;
the adaptive processing module comprises N adaptive processors, the adaptive processors are internally provided with adaptive algorithms, and weight values are generated according to adaptive spatial filters or beam forming algorithms and estimated incoming wave directions;
a beam forming network for performing a dynamic adaptive weighting process to generate a desired adaptive beam;
the antenna array elements, the radio frequency front ends, the analog-to-digital converters and the adaptive processors are in one-to-one correspondence, the input end of a first band-pass filter in the radio frequency front end is connected with the antenna array elements corresponding to the antenna array elements to receive signals, the output end of an intermediate frequency amplifier is connected with the analog-to-digital converters corresponding to the antenna array elements to output signals, the analog-to-digital converters are connected with the adaptive processors corresponding to the analog-to-digital converters, and each adaptive processor is connected to a beam forming network;
in the working state, the antenna utilizes the self-adaptive beam forming technology to form antenna radiation directional diagram null in the arrival direction of the interference signal, and forms a null point in the direction of the interference wave to shield the interference signal.
2. The GPS jammer-resistant antenna of claim 1, wherein the antenna array is a quaternary circular antenna array.
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| CN201410292998.7A CN104076368B (en) | 2014-06-25 | 2014-06-25 | GPS anti-interference antenna technology |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104635244A (en) * | 2015-02-03 | 2015-05-20 | 芜湖航飞科技股份有限公司 | Anti-interference antenna on satellite navigation receiver |
| CN106291605A (en) * | 2016-08-30 | 2017-01-04 | 北京航天长征飞行器研究所 | A kind of satellite navigation anti-interference reception system |
| CN106452549A (en) * | 2016-10-11 | 2017-02-22 | 西安华讯天基通信技术有限公司 | ADS-B long-distance anti-interference anti-deception receiving method and apparatus based on intelligent antenna |
| CN106646528A (en) * | 2016-11-03 | 2017-05-10 | 中国科学院云南天文台 | System and method of eliminating interference on navigation signals by solar radio burst based on auxiliary antenna |
| CN107666333A (en) * | 2017-01-20 | 2018-02-06 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Expansion/Frequency Hopping Signal system array antenna Adaptive beamformer system |
| CN108519608A (en) * | 2018-03-09 | 2018-09-11 | 中国航天电子技术研究院 | A kind of satellite navigation based on array antenna is anti-interference and surveys attitude positioning method |
| CN108768418A (en) * | 2018-06-05 | 2018-11-06 | 湖南智领通信科技有限公司 | A kind of antenna rf fore device having direction finding and active anti-interference function |
| CN110137695A (en) * | 2019-05-07 | 2019-08-16 | 北京国科导通科技有限公司 | Seven vibration element array antenna of one kind |
| CN112763822A (en) * | 2020-12-23 | 2021-05-07 | 北京无线电计量测试研究所 | Anti-interference antenna measuring device and measuring system |
| CN113495284A (en) * | 2021-09-02 | 2021-10-12 | 北京航空航天大学 | Satellite navigation deception jamming sensing and restraining system and method based on beam scanning |
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| CN108627803B (en) * | 2017-03-17 | 2021-10-08 | 南京理工大学 | Spectrum pairing method and system based on beam forming |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104635244A (en) * | 2015-02-03 | 2015-05-20 | 芜湖航飞科技股份有限公司 | Anti-interference antenna on satellite navigation receiver |
| CN106291605A (en) * | 2016-08-30 | 2017-01-04 | 北京航天长征飞行器研究所 | A kind of satellite navigation anti-interference reception system |
| CN106291605B (en) * | 2016-08-30 | 2018-08-21 | 北京航天长征飞行器研究所 | A kind of satellite navigation anti-interference reception system |
| CN106452549A (en) * | 2016-10-11 | 2017-02-22 | 西安华讯天基通信技术有限公司 | ADS-B long-distance anti-interference anti-deception receiving method and apparatus based on intelligent antenna |
| CN106646528A (en) * | 2016-11-03 | 2017-05-10 | 中国科学院云南天文台 | System and method of eliminating interference on navigation signals by solar radio burst based on auxiliary antenna |
| CN107666333A (en) * | 2017-01-20 | 2018-02-06 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Expansion/Frequency Hopping Signal system array antenna Adaptive beamformer system |
| CN108519608A (en) * | 2018-03-09 | 2018-09-11 | 中国航天电子技术研究院 | A kind of satellite navigation based on array antenna is anti-interference and surveys attitude positioning method |
| CN108768418A (en) * | 2018-06-05 | 2018-11-06 | 湖南智领通信科技有限公司 | A kind of antenna rf fore device having direction finding and active anti-interference function |
| CN108768418B (en) * | 2018-06-05 | 2020-03-31 | 湖南智领通信科技有限公司 | Antenna radio frequency front end device with direction finding and active anti-interference functions |
| CN110137695A (en) * | 2019-05-07 | 2019-08-16 | 北京国科导通科技有限公司 | Seven vibration element array antenna of one kind |
| CN112763822A (en) * | 2020-12-23 | 2021-05-07 | 北京无线电计量测试研究所 | Anti-interference antenna measuring device and measuring system |
| CN112763822B (en) * | 2020-12-23 | 2023-01-06 | 北京无线电计量测试研究所 | Anti-interference measuring device and measuring system of antenna |
| CN113495284A (en) * | 2021-09-02 | 2021-10-12 | 北京航空航天大学 | Satellite navigation deception jamming sensing and restraining system and method based on beam scanning |
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