A kind of radar general Big Dipper positioning and directing time service equipment
Technical field
The utility model is a kind of radar general Big Dipper positioning and directing time service equipment, is specifically related to a kind of radar general Big Dipper positioning and directing time service equipment.
Background technology
Beidou satellite navigation system (BeiDouNavigationSatelliteSystem) be China implementing independent development capability, independent operating GPS (Global Position System).System Construction target is: build up independent, open and compatible, advanced technology, reliable and stable Beidou satellite navigation system covering the whole world.There is the satellite navigation and positioning system of carrying out comprehensive real-time three-dimensional navigation and localization ability in sea, land and sky.
2000, first build up Beidou navigation pilot system, make China become the 3rd country having an autonomous satellite navigational system in the world after the United States, Russia.About the year two thousand twenty, Beidou satellite navigation system covering the whole world will be built up.At present, Beidou satellite navigation system should through covering Asia-Pacific region, and continue to provide high-quality location, navigation and time service service to user.Positioning precision 10 meters, rate accuracy 0.2 meter per second, time service precision 20 nanosecond.
At present, the positioning and directing of radar and communication antenna has several mode, respectively has relative merits:
Magnetic compass: advantage is that price is low; Shortcoming is subject to magnetic field environment impact, and have requirement to installation environment, magnetic compass itself can not be located;
North finder: north finder is the inertia north finding device relying on gyro, and advantage is that precision is high; Shortcoming is poor to the environmental suitability of impact shock, and price is high;
Big Dipper double antenna positioning and directing equipment: be the double antenna positioning and orienting device relying on Beidou satellite navigation system, advantage is that precision is high, cost performance is high; Shortcoming is non-autonomous type, needs passive reception satellite navigation system signals.But military industry field has not remilitarized the positioning and directing equipment relying on gps satellite navigational system.
Usual radar time service demand comprises two kinds of signals: standard-frequency signal and standard time code signal, and frequency signal is used for the transmission frequency of frequency multiplication to radar, and time code signal is used for the time synchronized of radar data process.This type of provides frequency for the built-in rubidium clock of radar time service clock product needed or crystal oscillator module, also will receive satellite navigation signals simultaneously and provide the time.
Therefore, my company have developed a kind of radar general Big Dipper positioning and directing time service equipment, single dipper system is utilized to realize to the positioning and directing of radar equipment and time service function, this integration of equipments several functions, output multi-channel time signal, there is the advantages such as high precision, miniaturization, universalization, meet the demand of national defense construction, have very large application market at military industry field.
Utility model content
The purpose of this utility model is, utilizes existing big-dipper satellite positioning and directing technology and satellite synchronization Service of Timing, provides a kind of equipment integrating Big Dipper positioning and directing and time service function.
The technical solution of the utility model is:
A kind of radar general Big Dipper positioning and directing time service equipment primarily of positioning and directing module and time frequency module composition, utilize Beidou satellite navigation system for the time service of radar system positioning and directing.Equipment composition comprises 2, Big Dipper measurement type antenna, device Host 1 and supporting connection cable (feed cable, data cable, feeder) 1 cover composition.
Device Host composition comprises two pieces of Beidou II navigation neceivers, center control core circuit, time-code unit microprocessor, rubidium atomic clock, digital phase-locked loop, time-code generation circuit, connector and housing.
Center control core circuit is connected with time-frequency functional module and positioning and directing functional module.Center control core circuit is used for Control on Communication, and core processor is used for decode satellite data, and the communication information of outputting standard form, provides status signal to system, receives external control instruction by network interface, produces control signal according to instruction.
Time-frequency functional module specifically comprises time-code unit microprocessor, rubidium atomic clock, digital phase-locked loop, time-code generation circuit; Time-frequency functional module provides the Primary Clock synchronizing signals such as 10Mhz, NTP, 1PPS, IRIG-B for subscriber equipment, is furnished with high steady rubidium clock, the function have free-running operation, catch soon, lock, keeping, when equipment loses all external timing reference sources, has certain reference clock hold facility;
Positioning and directing functional module comprises two pieces of Beidou II navigation neceiver modules and function bottom board.Two pieces of Big Dipper modules can receive Big Dipper satellite signal, wherein receiving element A utilizes the differential data received to carry out RTK location, receiving element A simultaneously issues receiving element B raw data, and receiving element B calculates the position angle of two aerial positions and the angle of pitch or roll angle according to the raw data of two boards.
Beidou II navigation neceiver while hi-Fix directed information is provided, for time frequency module provide time scale information and 1pps signal to time frequency module, time-frequency functional module mainly contains frequency marking and time-code produces two functions.The digital phase-locked loop of time-frequency functional module receives the 1pps of Big Dipper positioning and directing module output, and tame local high steady rubidium clock, make local 1pps signal synchronous with External Reference 1pps signal by taming loop, frequency marking unit utilizes rubidium clock punctual when satellite-signal is invalid.Time-code produces circuit and uses local 1pps reference signal and rubidium clock 10MHz signal, produces IRIG-B time service code and NTP.
Function tamed by time-frequency module local clock, receives the timing input signal that satnav orientation system provides, and tames local rubidium clock, improves 10MHz frequency accuracy, for external unit provides high precision time frequency signal.
Above-mentioned Big Dipper positioning and directing time service equipment, the information such as the split-second precision that positioning and directing module provides, longitude, latitude, course angle, the angle of pitch and speed, be sent to center control core circuit (processor is DSP), multiple decoded packet data is regrouped as radar private data format by DSP, is exported by network interface.Possess RJ45 network interface and export time of carrier, longitude, latitude, the information such as course and speed in real time.
For full range point high powered radar, the high-power RF signal sent when radar start transmitter can be fed back by receiving antenna, thus breaking-up Beidou navigation satellite system receiver, therefore the processor of instruction to equipment can be sent during radar work, director data bag is decoded by processor, produce corresponding control signal, control the automatic switching of Beidou navigation satellite system receiver.Receive external control instruction by RJ45 network interface simultaneously, resolve instruction, and according to sending corresponding control signal (send out code during radar start and then close Beidou receiver, just make Beidou receiver reopen when receiving and recovering instruction);
Big Dipper positioning and directing time service equipment adopts unitized 1U standard PC case, upper frame type mounting means.
Compared with prior art, the beneficial effects of the utility model are:
1. positioning and directing precision is high.Use Beidou II dash receiver on this radar general Big Dipper positioning and directing time service equipment, adopts carrier phase differential positioning technology, measures carrier wave (B1, B2) phase place, obtains carrier phase observation data.Utilize the various combination of these observed readings (asking poor) to carry out relative positioning, can effectively eliminate or the impact of attenuation of correlation error, eliminate ephemeris, troposphere, ionosphere equal error, and without accumulated time error, there is higher positioning and directing precision.
2. frequency time signal precision is high.High stability rubidium clock and the time service of Big Dipper high precision, frequency measurement and Time synchronization technique combine by this radar general Big Dipper positioning and directing time service equipment, rubidium clock output frequency is tamed be synchronized with on big-dipper satellite cesium-beam atomic clock signal, improve long-time stability and the accuracy of frequency signal.
3. this radar of use general Big Dipper positioning and directing time service equipment can simultaneously for radar work provides positioning and directing information and time and frequency standard, the combination function in the past needing multiple devices can be reached, save the use of resource, temporal frequency net synchronization capability is better, miniaturization, greatly simplify the composition of subscriber equipment, be easy to use, cost performance is high.
4. adopt controller centered by dsp chip, real-time property is good, and the speed of Systematical control sooner and accurately.
5., according to the network interface command information automatic switchover duty of radar transmitter, the work controlling Beidou navigation satellite system receiver, in order to avoid damaged, improves the reliability of system without the need to manual operation.
Accompanying drawing explanation
Fig. 1 is a) the structure front plate design drawing of a kind of radar of the utility model general Big Dipper positioning and directing time service equipment;
Fig. 1 b) be the structure upper cover plate design drawing of a kind of radar of the utility model general Big Dipper positioning and directing time service equipment;
Fig. 1 c) be the structure rear panel design drawing of a kind of radar of the utility model general Big Dipper positioning and directing time service equipment;
Fig. 2 is the process flow diagram of a kind of radar of the utility model general Big Dipper positioning and directing time service equipment process.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail:
Beidou satellite navigation system (BeiDou (COMPASS) NavigationSatelliteSystem) is that China is only in the GPS (Global Position System) of the independent development capability implemented, independent operating.At present, Beidou satellite navigation system should through covering Asia-Pacific region, and continue to provide high-quality location, navigation and time service service to user.Positioning precision 10 meters, rate accuracy 0.2 meter per second, time service precision 20 nanosecond.
The utility model radar general Big Dipper positioning and directing time service equipment can be all kinds of radar and provides high precision, highly reliable location, radar antenna orientation, radar frequency benchmark and time service service.Support BDSB1, B2 two frequency bins, positioning precision is better than 2 meters, 2 meters of base length orientation accuracies can reach 0.1 °, have 3 roads 1pps output interface (RS422), 3 road IRIG-B (DC) codes (RS422), 1 road NTP time service network interface, 1 road RJ45 network interface (export radar and require the information such as standard format time, longitude, latitude, course and speed, receiving control information), 1 road 10MHz export.
Digital phase-locked loop receives the 1pps that Big Dipper positioning and directing module exports, and tames local high steady frequency source (rubidium clock), makes local 1pps signal synchronous with External Reference 1pps signal by taming loop.Tame circuit by time-interval-unit, the digital unit such as loop filtering unit, Direct Digital Frequency Synthesizers forms.After taming, local 1pps reference signal reaches synchronous with satellite time transfer signal.
When satellite time transfer signal is unavailable, system automatically switches to Holdover mode.Automatically adjust control rubidium clock according to operation characteristics such as rubidium clock aging curve, rubidium clock frequency deviations, continue to keep high-precision time and frequency signal to export.This process is called that clock signal keeps.Clock is kept to be tamed on loop at clock by intelligent algorithm and carries out, and suitable adjustment loop filtering parameter, makes loop reach steady-working state under user control and make output signal adjust to perfect condition.
By high precision time interval measurement unit, measure the time difference between inner clock output 1pps signal and satellite time transfer signal (pulse per second (PPS)), calculate the frequency deviation of built-in clock relative to time dissemination system, and regulate and control internal clocking output frequency, clock output frequency is kept and time dissemination system time synchronized.
According to time the 10MHz reference frequency of frequency module locking and the synchronous 1pps pps pulse per second signal of generation, synchronous generation 10Hz look-at-me, receive multiple packets that Big Dipper positioning and directing module exports, by the time, longitude, latitude, highly, course, the information such as speed and duty, regroup as binary TCP/IP data protocol bag, be sent to radar controller receiving port with the frequency of 10Hz by RJ45.
Processor on the control core circuit board of center adopts DSP, DSP to possess the real-time that processing speed faster guarantees system, possesses higher computing progress simultaneously.Processor receives external control instruction by RJ45 interface circuit, resolving instruction, being in off-mode when receiving radar transmitter, the instruction of Big Dipper module start, central control unit sends corresponding 5V control signal pilot relay switch according to instruction and closes, and Big Dipper positioning and directing module powers up work; Be in off-mode when receiving radar transmitter, the instruction of Big Dipper module start, central control unit makes the control voltage of pilot relay be 0V according to instruction, and switch disconnects, and Big Dipper positioning and directing module power-down does not work.Time now, the continuous electricity of frequency module works on, frequency marking unit locking high precision basis on start to keep function, continue to export NTP, 1PPS, IRIG-B isochronon synchronizing signal, until Big Dipper module powers on and enters frequency behind location and catch state soon next time.
Above-mentioned Big Dipper positioning and directing time service equipment adopts unitized 1U standard PC case, upper frame type mounting means.Casing structure configuration design is shown in Fig. 1 a), Fig. 1 b), Fig. 1 c).