CN201788280U - Skyborne phased array Doppler meteorological radar - Google Patents
Skyborne phased array Doppler meteorological radar Download PDFInfo
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- CN201788280U CN201788280U CN2009202565383U CN200920256538U CN201788280U CN 201788280 U CN201788280 U CN 201788280U CN 2009202565383 U CN2009202565383 U CN 2009202565383U CN 200920256538 U CN200920256538 U CN 200920256538U CN 201788280 U CN201788280 U CN 201788280U
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Abstract
A skyborne phased array Doppler meteorological radar is characterized by mainly consisting of a phased array scanning antenna (2) installed in a radome at the front of an aircraft, a travelling wave tube (3), a digital receiver (4), a wave beam controller (5), a signal/data processor (6) and a power module (7). An output of the travelling wave tube (3) is transmitted through the phased array scanning antenna (2), echo signals are sent into the digital receiver (4) via the phased array scanning antenna (2), the digital receiver (4) is connected with the signal/data processor (6), the signal/data processor (6) is respectively connected with a data receiving system and wave beam controller (5) on the aircraft, and the wave beam controller (5) is connected with a control input end of the phased array antenna (2). The skyborne phased array Doppler meteorological radar fast and accurately measures precipitation and wind shear during flying of the aircraft, obtains strength of precipitation and atmospheric turbulence and Doppler speed, and has the advantages of complete function and compact structure.
Description
Technical field
The utility model relates to a kind of weather radar, especially a kind of airborne weather radar, specifically a kind of airborne radar Doppler weather radar.
Background technology
As everyone knows, China is subjected to meteorological disaster to influence one of the most serious country in the world.The meteorological disaster kind is many, intensity is big, frequency is high, and the serious threat people life property safety brings about great losses for country and society.Main disaster weather events comprises typhoon, heavy rain, arid and sudden weather etc.Weather system is implemented adaptability observation, follow the trail of observation in the sensitizing range continuously, will obviously improve the monitoring and the predictive ability of weather system.The aerological sounding Developing Trend in Technology is to realize the seamless covering observation of full-time sky in the integrated detection system of ground-space base-space-based.And China carries out active remote sensing aerological sounding means and is essentially blank in the aerological sounding field on space base and space-based.Utilize aircraft platform to carry out aerological sounding, the fine structure that can have high selectivity, high maneuverability to the object of being paid close attention to is surveyed, and improves the detectivity to weather system.
Airborne weather radar is measured but all adopt the mechanical scanning system to finish precipitation in developed countries such as U.S. widespread use.Because the technology limitation of mechanical scanning system own makes airborne weather radar be subjected to the restriction of sweep velocity, is difficult to finish the realization of complicated scanning strategy.And adopting the phased array system to make airborne weather radar, intensity, the doppler velocity that can finish more rapidly and accurately precipitation target and atmospheric turbulence are measured.
The antenna of phased-array radar is with mechanical scanning radar antenna difference, and it is to concern the sensing that changes wave beam by the signal phase that changes each antenna element in the radar array, thereby realizes beam scanning.Adopt the airborne weather radar of phased array system will possess following advantage:
Quick scan capability: the phased array weather radar generally can be finished radar beam formation and beam. position conversion in several microseconds, by launching a broad beam signal, shine meteorological target area, this instantaneous beam scanning can adopt gapless spatial beams to receive, and has increased the weather information acquisition capability greatly.This ability is very effective to the structure of quick detection storm, in flight environment of vehicle, can finish high density scans fast especially to the zone that needs are surveyed, get access to very real sexual intercourse target fine structure, provide high-spatial and temporal resolution, high-quality echo data.The phased array weather radar is the realization of scanning fast, the more data information of high-spatial and temporal resolution is provided, thereby provide the initial field information of approaching more true atmospheric condition for the numerical forecasting pattern, be Radar Data assimilation, precipitation quantitative estimation accurately, improve numerical model prediction ability etc. and lay a good foundation.
Strong anti-clutter capability of influence: various land clutters are surveyed weather and are had a significant impact in the flight environment of vehicle, the phased array weather radar adopts the method for phase weighting just can promptly adopt the antenna lobe with given shape to suppress the land clutter influence according to actual needs on diverse location neatly to the antenna radiation pattern figuration.
Because phased-array technique meets the development trend of weather radar, therefore adopt phased-array technique to make airborne Doppler weather radar and just can realize measurement, and effectively suppress the influence of land clutter precipitation and atmospheric turbulence.
Summary of the invention
The purpose of this utility model is at the technical deficiency part at present airborne weather radar, designs a kind of airborne weather radar with Doppler range rate measurement function that adopts the phased array system.
The technical solution of the utility model is:
A kind of airborne radar Doppler weather radar, it is characterized in that it is mainly by the phase-array scanning antenna 2 in the antenna house that is installed in aircraft forward, travelling-wave tube transmitter 3, digital receiver 4, beam-controller 5, signal/data processor 6 and power module 7 are formed, the output of travelling-wave tube transmitter 3 is by 2 emissions of phase-array scanning antenna, phase-array scanning antenna 2 is sent into echoed signal in the digital receiver 4, digital receiver 4 links to each other with signal/data processor 6, signal/data processor 6 links to each other with data receiving system and beam-controller 5 on the aircraft respectively, and beam-controller 5 links to each other with the control input end of phase-array scanning antenna 2.
Radar of the present utility model is when measuring precipitation target and atmospheric turbulence, at first control according to signal processor by transmitter, antenna is delivered in the radar carrier frequency low-power signal amplification that Frequency Synthesizer in the receiver produces, in antenna, radiate through beam shape and the sensing that forms expectation after the phase shift.The electromagnetic wave that radiate runs into precipitation target back reflection, become echoed signal, echoed signal is delivered to HF receiver after antenna receives, down coversion is delivered to processor later on and is carried out A/D conversion (if sampling), digital signal is carried out FFT/PPP by the parallel processor in the processing unit and is handled, obtain the raw data such as intensity, speed of target, raw data is carried out data processing through data processing module again and is formed the cloud atlas line output calculation of parameter of going forward side by side, and target component is sent to the aircraft avionics system by Multifunctional Interface Module.
The radar beam control system is calculated the phase shift controlling value that each phase shifter scanning of phased array needs in real time under the control of processing unit, drive phase shifter by driving circuit, realizes functions such as radar beam scanning, transition and special beam figuration.
The feeder line of radar partly is a passive network, and it finishes the distribution of emission exciting power, finishes the tasks such as wave beam formation of receiving cable simultaneously.
Receiver is finished the amplification and the conversion of signal, and output is adapted to the signal form of digital signal processing.In system, adopt Digital IF Processing, to guarantee higher receptivity.
Signal processor carries out pulse compression, coherent accumulation, filtering, analysis of spectrum etc. to it after receiving the digital signal that digital intermediate frequency is sent here.Regularly realize that with the interface subsystem system-wide network is connected, carry out the internal system data transmission, comprising each required triggertiming pulse signal of distribution, the transmission of duty, the system works of work order etc.Main control computer to the beam. position of system works, PRF setting, working method etc. all states realize control.
The course of work of phased array weather radar is freedom and flexibility very, can be operated under the prefabricated mode of operation, also can specify observation spatial domain, beam position and the working method of radar according to actual conditions by the man-machine interface of data handling system arbitrarily by the radar operation personnel.
The beneficial effects of the utility model:
The utility model has solved the sweep velocity problem when airborne weather radar is surveyed precipitation target and atmospheric turbulence, utilize phased array antenna, realized the scanning strategy of the scanning fast of separate unit radar, jump scanning and spotting scaming, measure by wave beam forming and ground velocity, can in time suppress in-flight land clutter the radar detection Effect on Performance.
The utility model is applied to phased array antenna the airborne weather radar field first, has advantage simple in structure, highly sensitive.
The utility model has solved the problem that aircraft is quick and precisely measured precipitation and wind shear awing, obtains the intensity and the doppler velocity of precipitation and atmospheric turbulence, has an advantage multiple functional, compact conformation.
Description of drawings
Fig. 1 is a composition structured flowchart synoptic diagram of the present utility model.
Fig. 2 is an antenna composition frame chart of the present utility model.
Fig. 3 is a wave beam control composition frame chart of the present utility model.
Fig. 4 is a transmitter composition frame chart of the present utility model.
Fig. 5 is a receiver composition frame chart of the present utility model.
Fig. 6 is signal of the present utility model/data processing composition frame chart.
Embodiment
Below in conjunction with drawings and Examples the utility model is further described.
Shown in Fig. 1-6.
A kind of airborne radar Doppler weather radar, it is mainly by the phase-array scanning antenna 2 in the antenna house that is installed in aircraft forward, travelling-wave tube transmitter 3, digital receiver 4, beam-controller 5, signal/data processor 6 and power module 7 are formed, the output of travelling-wave tube transmitter 3 is by 2 emissions of phase-array scanning antenna, phase-array scanning antenna 2 is sent into echoed signal in the digital receiver 4, digital receiver 4 links to each other with signal/data processor 6, signal/data processor 6 links to each other with data receiving system and beam-controller 5 on the aircraft respectively, and beam-controller 5 links to each other with the control input end of phase-array scanning antenna 2.Details are as follows:
The utility model is to adopt intensity, the doppler velocity of phased array system design airborne weather radar to obtain precipitation target and atmospheric turbulence.The airborne radar Doppler weather radar is made up of phase-array scanning antenna, travelling-wave tube transmitter, digital receiver, beam-controller, signal/data processor and power module, connect annexes such as waveguide, unit rack between the each several part in addition, entire equipment is installed in the antenna house of aircraft forward.Radar finish by the Multifunctional Interface Module in signal/data processor and aircraft between data crosslinked.
The phase-array scanning antenna adopts the passive phased array antenna of waveguide constrained feed formula, mainly comprises compositions such as antenna radiator, phase shifter, ripple control phasing, feeder network, ripple control device, feeder assembly and front structural framing.The phase-array scanning antenna is formed as shown in Figure 2.
Passive phased array antenna is made up of about 1500 radiating elements, totally 40 is listed as, and radiating element is by rounded projections arranged.The ferrite phase shifter of the corresponding high reliability in each unit, beam steering system carries out initial calibration and compensation to ferrite phase shifter.Per two row's phase shifters are formed phase shifter package with the structural transition plate; Article one, Denso such as phase shifter package and a row feedback and socket, cabling plate becomes a linear array, and entire antenna has 20 linear arrays.The corresponding Drive and Control Circuit plate of per half bar linear array, entire antenna has 40 blocks of Drive and Control Circuit plates.The waveguide power distributing network is accurately controlled front bore amplitude weighting, makes phased array both keep higher bore usage factor, realizes Low Sidelobe again.Feeding network mainly is made up of row feedback network and row feedback network.During emission, signal is imported by port, exports 4 constant amplitude in-phase signals, enters the row feedback, is assigned to each phase shifter through the row feedback again, radiate via antenna element.During reception, after echoed signal is received by antenna, through phase shifter, row feedback network, row feedback network synthesized output signal.
Between each delivery outlet of power division network and radiating element, be connected in series ferrite phase shifter.First phase compensation and beam scanning are to realize by the phase place that ripple control device is controlled phase shifter.When needs during with a certain direction of beam position, the ripple control finish radiating surface phase calculation, calculate efferent echo control scan code, determine the required phase place ripple control code of final phase-shift phase of each phase shifter radiating element, the work of control phase shifter.Change the phase place of each phase shifter by predetermined rule, realize beam scanning.
Form special PHASE DISTRIBUTION on the radiating surface by beam controlling system control phase shifter, can form special beam shape, thereby satisfy the different request for utilization of radar.
As shown in Figure 3, centralized phase calculation ripple prosecutor formula is adopted in wave beam control, is made up of beam steering module and ripple control driving circuit, finishes the beam scanning control of airborne radar Doppler weather radar.The front ripple control circuit of being made up of several circuit modules on the antenna element has used special-purpose asic chip on the circuit module.
Processing unit is to antenna transmission ripple control code, and carrier frequency is encoded, working method, information such as effect sign indicating number.The beam position sign indicating number that beam controlling system is sent radar computer here is converted into the phase-shift phase of each phase shifter of antenna, and finish compensation, the frequency compensation of initial phase correction, phase shifter, other special figuration weightings etc. form final phase-shift phase, by phase shifter phasing circuit excitation phase shifter and locking, the victory that realizes controlling antenna wave beam to point becomes, and sends new beam position sign indicating number up to radar computer.
The high frequency link of transmitter of the present utility model adopts the main amplifying type system of shaking, and high frequency link center heart device is the grid pulse travelling-wave tube.Whole transmitter is made up of 6 modules such as distribution rectification module, power inverter module, high-voltage power module, pulse modulation module, control guarantor and pre-amplifier module and travelling-wave tube, also has some high-frequency components and structural member in addition.Transmitter module division synoptic diagram as shown in Figure 4.
The prime solid-state amplifier amplifies the low-power radio frequency signal that radar system provides in advance, obtains to satisfy the radiofrequency signal of travelling-wave tube excitation, and the design of radio frequency link can adapt to the exciting power requirement of different rows wave duct.Travelling-wave tube is high frequency link master amplifier tube, has control protection electric circuit, and waveguide and coaxial component are the microwave transmission element.Modulator is made up of presetting circuit, burst transmissions transformer, noble potential modulation circuit etc.Travelling-wave tube work control is finished by modulator, when each pole tension of travelling-wave tube is added to ratings, and the work of modulator control travelling-wave tube, when modularot output voltage is specified negative bias voltage, travelling-wave tube is not worked, when modularot output voltage is specified positive gate voltage, and travelling-wave tube work.
Power supply is made up of low-tension supply, high-voltage power supply, filament modulation power source.Low-tension supply provides the required power supplies of low pressure parts work such as system's control protection electric circuit, power supply auxiliary control circuit and prime solid-state amplifier.High-voltage power supply provides travelling-wave tube work required most of power supply, and the filament modulation power source provides power supply for travelling-wave tube filament and modulator circuit.
Control is made up of control interface board and control figure plate with holding circuit.Switching on and shutting down and the fault detection capability that circuit is mainly being served as transmitter protected in control, and the protection item has overvoltage, under-voltage, overcurrent etc.
Receiver comprises front end, multi-functional Frequency Synthesizer and if sampling processing.Receiver front end is that separate unit is a receiving element, is installed on the structure on the antenna element, and other functional modules of receiver are placed in the processing unit.Receiver is formed as shown in Figure 5.
Receiving subsystem is a high intermediate-frequency receiver of single channel, finishes amplification and twice down coversion of radar echo signal, and output intermediate-freuqncy signal (arrowband) is sent A/D sampling, and narrow band signal is realized if sampling and digital quadrature I/Q demodulation by the DDC module.
Multi-functional Frequency Synthesizer produces various radar detection pumping signals, possesses the high pure frequency spectrum characteristic, and have subelement parameter control in transmission frequency and mode of operation control, waveform and timing controlled, the receiving cable, with function such as radar computer communication; For radar provides the high stable reference signal,,, I/Q provide the high precision frequency controlled local oscillation signal for examining circuit mutually for receiver provides high pure frequency spectrum one local oscillator and two local oscillation signals, blanking and various control signal are provided; Interface circuit can be accepted computer instruction, functions such as completion status control, fault detect and isolation.The frequency device is formed and is comprised formations such as reference source, driving source assembly, local oscillator assembly, modulation component, and pulsed modulation rf excitation signal, reception local oscillation signal, the employed phase-modulated signal of pulse compression and the System self-test signal etc. of transmitter can be provided.
The if sampling signal that signal/data processor is finished receiver output carries out digital processings such as pre-service, filtering, coherent accumulation, target detection, image formation, and finishes the BIT of system detection and the BIT of self detection; Signal/data processor produces full machine timing signal, realizes the timing controlled to each extension set of radar.
Signal/data processor comprises three kinds of modules: main control module, and TS201 module and time block, as shown in Figure 6.Main control module is mainly realized signal Processing control and aftertreatment work.Master control borad is accepted the order that data processor transmits by DPBUS, by GBUS order is sent to timer and TS201 module, accepts the result that the TS201 module sends here then and carries out aftertreatment, gives data processor with data at last.Timer module produces the required various timing signals of the full machine of radar, realizes the timing controlled to each extension set of radar.This module receives master control borad by GBUS and sends order here, produces timing signal, and gives Frequency Synthesizer with controlled variable by quick serial port.
Principle of work of the present utility model is:
Radar is when measuring precipitation target and atmospheric turbulence, transmitter is controlled according to signal processor, the radar carrier frequency low-power signal that Frequency Synthesizer in the receiver produces is delivered to the travelling-wave tube transmitter, microwave signal by transmitter output is divided into four the tunnel behind feeder network, a feed quadrant of array of each Lu Jingyi group waveguide series-feed power division network is radiated to the space by radiating element through beam shape and the direction that forms expectation after the phase shift.The electromagnetic wave that radiate runs into precipitation target back reflection, becomes echoed signal, and radar transfers accepting state to, the signal that the radiating element of four quadrants receives is synthetic through the series feed power division network of waveguide respectively, be transferred to feeder network, in feeder network, synthesize, form wave beam.Echoed signal is delivered to HF receiver, down coversion is delivered to processor later on and is carried out A/D conversion (if sampling), digital signal is carried out FFT/PPP by the parallel processor in the processing unit and is handled, obtain the raw data such as intensity, speed of target, raw data is carried out data processing through data processing module again and is formed the cloud atlas line output calculation of parameter of going forward side by side, and target component is sent to the aircraft avionics system by Multifunctional Interface Module.
The utility model does not relate to the part prior art that maybe can adopt all same as the prior art to be realized.
Claims (1)
1. airborne radar Doppler weather radar, it is characterized in that it is mainly by the phase-array scanning antenna (2) in the antenna house that is installed in aircraft forward, travelling-wave tube transmitter (3), digital receiver (4), beam-controller (5), signal/data processor (6) and power module (7) are formed, the output of travelling-wave tube transmitter (3) is launched by phase-array scanning antenna (2), phase-array scanning antenna (2) is sent into echoed signal in the digital receiver (4), digital receiver (4) links to each other with signal/data processor (6), signal/data processor (6) links to each other with data receiving system and beam-controller (5) on the aircraft respectively, and beam-controller (5) links to each other with the control input end of phase-array scanning antenna (2).
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| CN2009202565383U CN201788280U (en) | 2009-11-13 | 2009-11-13 | Skyborne phased array Doppler meteorological radar |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2009202565383U CN201788280U (en) | 2009-11-13 | 2009-11-13 | Skyborne phased array Doppler meteorological radar |
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| CN201788280U true CN201788280U (en) | 2011-04-06 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103245950A (en) * | 2012-02-09 | 2013-08-14 | 北京雷音电子技术开发有限公司 | Meteorological terminal matched and connected with multifunctional radar |
| CN104111459A (en) * | 2013-04-16 | 2014-10-22 | 空中客车营运有限公司 | Airborne weather radar with rotable antenna |
| CN104809944A (en) * | 2015-04-21 | 2015-07-29 | 中国人民解放军海军工程大学 | Orthogonal receiver comprehensive experiment device |
| CN107831492A (en) * | 2017-06-29 | 2018-03-23 | 南京航空航天大学 | A kind of airbome windshear instrument and wind shear detection method |
| CN112987001A (en) * | 2021-02-10 | 2021-06-18 | 南京恩瑞特实业有限公司 | C-band phased array weather radar |
-
2009
- 2009-11-13 CN CN2009202565383U patent/CN201788280U/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103245950A (en) * | 2012-02-09 | 2013-08-14 | 北京雷音电子技术开发有限公司 | Meteorological terminal matched and connected with multifunctional radar |
| CN104111459A (en) * | 2013-04-16 | 2014-10-22 | 空中客车营运有限公司 | Airborne weather radar with rotable antenna |
| CN104111459B (en) * | 2013-04-16 | 2016-08-17 | 空中客车营运有限公司 | There is the airborne weather radar of rotable antenna |
| CN104809944A (en) * | 2015-04-21 | 2015-07-29 | 中国人民解放军海军工程大学 | Orthogonal receiver comprehensive experiment device |
| CN107831492A (en) * | 2017-06-29 | 2018-03-23 | 南京航空航天大学 | A kind of airbome windshear instrument and wind shear detection method |
| CN107831492B (en) * | 2017-06-29 | 2021-12-14 | 南京航空航天大学 | Airborne wind shear instrument and wind shear detection method |
| CN112987001A (en) * | 2021-02-10 | 2021-06-18 | 南京恩瑞特实业有限公司 | C-band phased array weather radar |
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Granted publication date: 20110406 |
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