CN108594167A - A kind of antenna angle-measuring equipment for AIS communication systems - Google Patents
A kind of antenna angle-measuring equipment for AIS communication systems Download PDFInfo
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- CN108594167A CN108594167A CN201810756322.7A CN201810756322A CN108594167A CN 108594167 A CN108594167 A CN 108594167A CN 201810756322 A CN201810756322 A CN 201810756322A CN 108594167 A CN108594167 A CN 108594167A
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- ais
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- communication systems
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- 238000004891 communication Methods 0.000 title claims abstract description 40
- 238000005516 engineering process Methods 0.000 abstract description 11
- 238000011161 development Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000008520 organization Effects 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000000205 computational method Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
- G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
- G01S3/02—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
- G01S3/14—Systems for determining direction or deviation from predetermined direction
- G01S3/28—Systems for determining direction or deviation from predetermined direction using amplitude comparison of signals derived simultaneously from receiving antennas or antenna systems having differently-oriented directivity characteristics
-
- 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
- G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
- G01S3/02—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
- G01S3/14—Systems for determining direction or deviation from predetermined direction
- G01S3/46—Systems for determining direction or deviation from predetermined direction using antennas spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/06—Receivers
- H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
- H04B1/12—Neutralising, balancing, or compensation arrangements
- H04B1/123—Neutralising, balancing, or compensation arrangements using adaptive balancing or compensation means
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0837—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using pre-detection combining
- H04B7/0842—Weighted combining
- H04B7/086—Weighted combining using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/52—TPC using AGC [Automatic Gain Control] circuits or amplifiers
Abstract
The invention discloses a kind of antenna angle-measuring equipments for AIS communication systems, including radio-frequency transmitter, splitter, phase or amplitude comparator and baseband processor, the radio-frequency transmitter is separately connected splitter and phase or amplitude comparator, phase or amplitude comparator are also connected with baseband processor, and the present invention provides the functions of can be used for measuring reception sense in AIS communication systems.Realizing can be according to the direction for receiving signal, to realize the direction propagation of AIS information in AIS communication systems.This technology and other maritime communication technology fit applications, which can also be realized, to be improved the communication distance of maritime communication system, reduces noise, improves the functions such as emission effciency.
Description
Technical field
The present invention relates to the field of communication technology of maritime electronic equipment, specifically a kind of antenna for AIS communication systems
Angle-measuring equipment.
Background technology
In recent years, with the emergence of the rapid development and marine economy of ship science and technology, the status of maritime traffic transport is increasingly
Significantly, world shipping market has obtained unprecedented expansion and development.The fast development of world shipping industry is bringing huge warp
While interests of helping, maritime traffic situation is also made to become to become increasingly complex.
AIS communication systems are a kind of effective Collision Avoidance At Sea, navigation, navaid security system, be since radar application again
One advanced maritime communication system.According to the mandatory requirement of International Maritime Organization (IMO), current all 300 tons or more international boats
Oceangoing ship and 500 tons or more non-International Voyage Ship of navigating have been mounted with AIS equipment.Although current spitkit is not forced to pacify
This equipment is filled, but due to the report position characteristic certainly of AIS and continuously decreasing for manufacturing cost, AIS is gradually applied to marine site sense
Know, surface monitoring, hydrometeorology, rescue at sea, assist in identifying, lie fallow, is environmentally friendly, seizing smugglers or smuggled goods, combat terrorism etc..It is international
Telecommunication union (ITU) and International Maritime Organization are the making subjects of AIS technical standards.
AIS systems are by broadcast communication mode, with self-organizing time division multiple acess TDMA (Time Division Multiple
Access it is) communication protocol, establishes what navigation data exchanged between some other ship and the seashore station with around in this ship
System.AIS transmitters are operated on two VHF (very high frequency(VHF)) channels, and each channel is respectively divided into 2250 time slots by per minute, often
Ship emits signal using a time slot to surrounding every time.When work on two channels alternate emission AIS information.
Since AIS systems use VHF communication, being restricted by frequency characteristic used in VHF, its communication distance is relatively limited, and one
As communication distance be about 20 to 50 nautical miles or so.Its practical communication distance depends on transmission power, receiving sensitivity, weather conditions
With the factors such as antenna height.
AIS satellite systems SAT-AIS (Satellite AIS) be in recent years gradually a kind of adopted ship's fix skill
Art, the AIS message informations that system is sent by the satellite reception ship of low orbit, satellite is then by the AIS after receiving the decode
Message information is transmitted to corresponding earth station, and AIS message informations are pushed to internet by earth station again, for needing to obtain information
Terminal access, to realize the long-range propagation of AIS information.Although AIS satellite systems extend spread scope, but due to needing
By the switching of earth station and the delay of internet, so there are hysteresis for the propagation of information.This lag is for emergent
It is sometimes unacceptable for the very high information of the requirement of real-time such as alarm, wave forecast, rescue and relief work.Secondly as AIS
Terminal must keep the connection of internet, and the access rate of internet, which are one, for the ship in blue water to neglect
Depending on expenditure.
On the other hand, for the slot efficiency of whole world AIS channels, at present major port and some interior river valleies when
Gap utilization rate is higher, some congestion phenomenon even occur, but on the ground for occupying the most of ocean in marine site He closing on bank base
The utilization rate of square AIS channels is still very low.Such as in Atlantic Oceanic Region of about 120 nautical miles from Liverpool, UK, although being in
The utilization rate of the main channel of American-European cargo transport, AIS channels only has 20% or so, and remaining about 80% time slot is in idle shape
State.
Based on this, it is necessary to which designing a kind of AIS communication systems of optimization can utilize the free timeslot of channel to realize information
Force transfer delivered in relays, traveled to by multiple AIS receivers to the AIS information sent from first AIS terminals
Farther place is gone.A key technology for realizing this system, which is exactly AIS terminals, can identify the AIS information sources received
Direction, to realize the direction propagation of AIS information, avoid AIS information two or more terminal rooms constantly repeat send or
Person to hair, wastes the communication resource back and forth.This technology and other maritime communication technology fit applications can also realize improve maritime affairs without
The communication distance of line communication system reduces the functions such as noise.
The antenna of current AIS terminals use isotropic receiving antenna, thus and without measure receive signal angle work(
It can, it is therefore necessary to design a kind of antenna angle-measuring method and device for AIS communication systems.
Invention content
The purpose of the present invention is to provide a kind of antenna angle-measuring equipments for AIS communication systems, to solve above-mentioned background
The problem of being proposed in technology.
To achieve the above object, the present invention provides the following technical solutions：
A kind of antenna angle-measuring equipment for AIS communication systems, including radio-frequency transmitter, splitter, phase or amplitude ratio
Compared with device and baseband processor, the radio-frequency transmitter is separately connected splitter and phase or amplitude comparator, phase or amplitude ratio
It is also connected with baseband processor compared with device.
As a further solution of the present invention：It is also associated with local oscillator on the splitter.
As a further solution of the present invention：The radio-frequency transmitter have it is multiple, multiple radio-frequency transmitters with it is independent
Reception antenna is connected, and multiple reception antennas rearrange aerial array.
As further scheme of the invention：Antenna angle measurement according to claim 2 for maritime communication fills
It sets, which is characterized in that the local oscillator is voltage controlled oscillator.
As further scheme of the invention：The radio-frequency transmitter includes radio-frequency front-end, frequency mixer, intermediate frequency amplifier
And automatic gain controller, radio-frequency front-end connect frequency mixer, radio-frequency front-end, frequency mixer, intermediate frequency amplifier and automatic growth control
Device connects intermediate frequency amplifier and splitter, intermediate frequency amplifier are also respectively connected with phase or amplitude comparator and automatic growth control
Device.
Compared with prior art, the beneficial effects of the invention are as follows：The present invention provides can be used for surveying in AIS communication systems
Amount receives the function in the direction of signal.Realizing can be according to the direction for receiving signal in AIS communication systems, and then realizes AIS
The direction propagation of information.This technology and other maritime communication technology fit applications, which can also be realized, improves maritime affairs wireless communication system
Communication distance, reduce noise, improve the functions such as emission effciency.
Description of the drawings
Fig. 1 is a kind of system structure diagram of antenna angle-measuring equipment for AIS communication systems of the present invention.
Fig. 2 is the detailed maps of radio-frequency transmitter internal structure in Fig. 1.
Fig. 3 is the computational methods schematic diagram of the antenna angle-measuring equipment for AIS communication systems.
Specific implementation mode
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation describes, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
- 3 are please referred to Fig.1, embodiment 1：In the embodiment of the present invention, a kind of antenna angle-measuring equipment for AIS communication systems,
The antenna receiving array, phase or the amplitude comparator 2 that are made of multiple independent radio-frequency transmitters, baseband processor 3, local oscillator 4,
Splitter 5 collectively constitutes.
Multiple independent radio-frequency transmitters are connected with external antenna, and mutiple antennas array element rearranges aerial array.Every group
The radiofrequency signal that radio-frequency transmitter individual reception antenna transmits, and it is ultimately routed to phase or amplitude comparator 2, do further place
Reason.
Phase or amplitude comparator 2 are connected with multi-channel rf receiver, the phase of intermediate-freuqncy signal to receiving or shake
Width (or both simultaneously) is compared.
Baseband processor 3 is connected with phase or amplitude comparator 2, for the intermediate-freuqncy signal after comparison, further completes mould
Number conversion (A/D), digital processing, the digital signal to output for judging antenna array receiver to signal angle.Local oscillator 4
Usually frequency oscillator generates low frequency signal, for being mixed with high-frequency signal.Preferably, the present invention is shaken using voltage-controlled
Swing device.Splitter 5 and local oscillator 4 connect, and are received per road to being sent into after being amplified, match from the low frequency signal that local oscillator 4 receives
The frequency mixer 1.2 of machine carries out down conversion process.
Radio-frequency transmitter is connected with external antenna.The radiofrequency signal that radio-frequency transmitter individual reception antenna transmits.Radio frequency connects
Receipts machine includes radio-frequency front-end 1.1, frequency mixer 1.2, intermediate frequency amplifier 1.3 and automatic gain controller 1.4.Outside radio-frequency front-end 1.1
Antenna is connect, the radiofrequency signal to come from antenna reception is filtered, low noise amplification, is then fed into frequency mixer 1.2.Frequency mixer
1.2 and radio-frequency front-end 1.1 connect, the radiofrequency signal that comes of reception and the low frequency signal sended over by splitter 5 are mixed
Frequently, to which radiofrequency signal is mixed down to intermediate frequency.Intermediate frequency amplifier 1.3 and frequency mixer 1.2 connect, and place is amplified to intermediate-freuqncy signal
Reason.Automatic gain controller 1.4 and intermediate frequency amplifier 1.3 connect, and receive the signal sent out from intermediate frequency amplifier 1.3,
To dynamically adjust gain parameter according to signal amplitude, intermediate frequency amplifier 1.3 is fed back to.
Carry out detailed for the implementation of the present invention further below for example, using phase or amplitude in this example
Comparator calculates different antennae and receives the phase difference of signal to judge the direction of reception signal.Similar, of the invention implementation
Different antennae can also be calculated using phase or amplitude comparator 2 receives the difference of vibration of signal to judge the direction of reception signal.
The baseline length of two antennas as shown in Figure 3 is d, and target direction angle is θ, and AIS transmitting signals are expressed as
To which the signal that described two antennas receive is just：
Wherein t1, t2 are respectively the reception signal in the airborne spread time for reaching two antennas, f0It is signal in sky
Frequencies of propagation in gas.
As shown in figure 3, the signal that receives is in the propagation distance poor (wave path-difference) for reaching two antennas
Δ R=dsin θ ... ... (4)
Therefore, the signal that receives is expressed as in the propagation phase difference for reaching two antennas：
Wherein c is the speed that wireless signal is propagated in air.
Formula (5) after deformation by being shown as：
It can be released by formula (6) as a result,：In known wavelength (λ), phase difference (φ) and two receiver antennas
In the case of spatial coordinate location distance (d), the sine value (Sin θ) for receiving signal angle can be obtained by numerical operation, from
And extrapolate the angle, θ for receiving signal.
Due to easy to implement than phase on lower frequency, therefore the high frequency for receiving described two antennas of the present invention preferentially is believed
It number is carried out than phase after being mixed with same local oscillation signal, then in intermediate frequency.The Computing Principle and phase described above that implementing phase compares
Together.
Because there is very big error and randomness in the handling result of two receivers, thus the present invention it is preferential selection it is multiple
(being more than 2) radio-frequency transmitter forms array acceptor, calculates mutual phase or the difference of amplitude, then optimizes processing.Tool
The Computing Principle and the same as above of body implementing phase or Amplitude Comparison.
Embodiment 2：Local oscillator 4 in the design uses voltage controlled oscillator, and only transceiver does not provide stable local oscillation signal,
The clock signal needed for entire circuit can be generated with frequency multiplication.Its phase noise, adjusts sensitivity to wirelessly receiving at adjustable range
The performance of hair machine has a significant impact.
It is obvious to a person skilled in the art that invention is not limited to the details of the above exemplary embodiments, Er Qie
In the case of without departing substantially from spirit or essential attributes of the invention, the present invention can be realized in other specific forms.Therefore, no matter
From the point of view of which point, the present embodiments are to be considered as illustrative and not restrictive, and the scope of the present invention is by appended power
Profit requires rather than above description limits, it is intended that all by what is fallen within the meaning and scope of the equivalent requirements of the claims
Variation is included within the present invention.Any reference signs in the claims should not be construed as limiting the involved claims.
In addition, it should be understood that although this specification is described in terms of embodiments, but not each embodiment is only wrapped
Containing an independent technical solution, this description of the specification is merely for the sake of clarity, and those skilled in the art should
It considers the specification as a whole, the technical solutions in the various embodiments may also be suitably combined, forms those skilled in the art
The other embodiment being appreciated that.
Claims (5)
1. a kind of antenna angle-measuring equipment for AIS communication systems, including radio-frequency transmitter, splitter, phase or Amplitude Comparison
Device and baseband processor, which is characterized in that the radio-frequency transmitter is separately connected splitter and phase or amplitude comparator, phase
Or amplitude comparator is also connected with baseband processor.
2. the antenna angle-measuring equipment according to claim 1 for AIS communication systems, which is characterized in that the splitter
On be also associated with local oscillator.
3. the antenna angle-measuring equipment according to claim 1 for AIS communication systems, which is characterized in that the radio frequency connects
Receipts machine has multiple, and multiple radio-frequency transmitters are connected with independent reception antenna, and multiple reception antennas rearrange antenna array
Row.
4. the antenna angle-measuring equipment according to claim 2 for AIS communication systems, which is characterized in that the local oscillator is
Voltage controlled oscillator.
5. the antenna angle-measuring equipment according to claim 1 for AIS communication systems, which is characterized in that the radio frequency connects
Receipts machine includes radio-frequency front-end, frequency mixer, intermediate frequency amplifier and automatic gain controller, and radio-frequency front-end connects frequency mixer, before radio frequency
End, frequency mixer, intermediate frequency amplifier and automatic gain controller connect intermediate frequency amplifier and splitter, and intermediate frequency amplifier also connects respectively
Connect phase or amplitude comparator and automatic gain controller.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810756322.7A CN108594167A (en) | 2018-07-11 | 2018-07-11 | A kind of antenna angle-measuring equipment for AIS communication systems |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810756322.7A CN108594167A (en) | 2018-07-11 | 2018-07-11 | A kind of antenna angle-measuring equipment for AIS communication systems |
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| Publication Number | Publication Date |
|---|---|
| CN108594167A true CN108594167A (en) | 2018-09-28 |
Family
ID=63615260
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| CN201810756322.7A Pending CN108594167A (en) | 2018-07-11 | 2018-07-11 | A kind of antenna angle-measuring equipment for AIS communication systems |
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|---|---|---|---|---|
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| CN103140985A (en) * | 2010-03-18 | 2013-06-05 | 阿尔卡特朗讯 | Antenna array calibration |
| US20150372710A1 (en) * | 2013-01-29 | 2015-12-24 | Srt Marine Technology Ltd | Reversible tdd transceiver |
| CN105929377A (en) * | 2016-05-16 | 2016-09-07 | 武汉大学 | High-frequency radar ship azimuth estimation method based on monopole intersected loop antenna |
| CN208350984U (en) * | 2018-07-11 | 2019-01-08 | 深圳市夸克云电子信息技术有限公司 | A kind of antenna angle-measuring equipment for AIS communication system |
-
2018
- 2018-07-11 CN CN201810756322.7A patent/CN108594167A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008148274A (en) * | 2006-11-14 | 2008-06-26 | Renesas Technology Corp | Semiconductor integrated circuit for rf communication |
| CN103140985A (en) * | 2010-03-18 | 2013-06-05 | 阿尔卡特朗讯 | Antenna array calibration |
| CN102545935A (en) * | 2011-12-08 | 2012-07-04 | 南京航空航天大学 | Calibration receiving device and calibration receiving method of radio frequency simulation system |
| US20150372710A1 (en) * | 2013-01-29 | 2015-12-24 | Srt Marine Technology Ltd | Reversible tdd transceiver |
| CN105929377A (en) * | 2016-05-16 | 2016-09-07 | 武汉大学 | High-frequency radar ship azimuth estimation method based on monopole intersected loop antenna |
| CN208350984U (en) * | 2018-07-11 | 2019-01-08 | 深圳市夸克云电子信息技术有限公司 | A kind of antenna angle-measuring equipment for AIS communication system |
Non-Patent Citations (1)
| Title |
|---|
| 官永强: "星载AIS接收机的多用户分离算法研究", 《中国优秀硕士学位论文全文数据库· 工程科技Ⅱ辑》 * |
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