Summary of the invention
The present invention provides the integrated receive-transmit system of a kind of micro-nano satellite telemetry communication and its implementation, in order to solving defective of the prior art, realizes high integrated, low-power consumption, reliable and anti-interference is higher.
The present invention provides the implementation method of the integrated receive-transmit system of a kind of micro-nano satellite telemetry communication in fact, may further comprise the steps:
1) upward signal is handled;
11) carry out power amplification, simulation frequency conversion, the up analog if signal of automatic gain control formation through star ground radio frequency reception channel received RF signal and to it;
12) the up analog if signal from star ground radio frequency reception channel that receives is carried out analog to digital conversion and form the upstream digital intermediate-freuqncy signal; Through digital frequency reducing and be divided into two-way; The up channel of leading up to carries out QPSK demodulation, channel-decoding and protocol processes and obtains line number biography data; Transfer to spaceborne computer through interface and handle, accomplish the number biography of ground to satellite; Another road obtains the observing and controlling vision signal through the PM demodulation; Said observing and controlling vision signal is carried out obtaining sidetone signal and up PCM remote control frame respectively after range tone filtering and the BPSK demodulation; Sidetone signal is delivered to said receive-transmit system down channel, with the synthetic descending PM modulation signal of telemetered signal; Convert said up PCM remote control frame to remote control command through protocol processes, deliver to spaceborne computer through interface and accomplish remote control;
2) downstream signal is handled;
21) obtain two paths of data through interface from spaceborne computer and memory cell; One circuit-switched data is descending PCM telemetry frame; Said descending PCM telemetry frame is carried out descending telemeter channel formatting, chnnel coding and BPSK modulation; Form the PCM/PSK telemetered signal; After said sidetone signal merging, carry out descending observing and controlling carrier wave PM modulation again, form descending observing and controlling channel modulated signal; Another circuit-switched data is that down line number passes frame, said line number down pass frame through line number down deliver a letter the form layout, line number passes carrier wave QPSK modulation down, forms down the line number modulated signal of delivering a letter; Merge said descending observing and controlling channel modulated signal and the said down line number modulated signal of delivering a letter, through filtering interpolation, numeral increases and forms descending digital medium-frequency signal frequently; Said descending digital medium-frequency signal is formed descending analog if signal through digital-to-analogue conversion send into star ground radio-frequency transmissions passage.
22) receive said descending analog if signal and it is carried out power amplification, the control of simulation frequency conversion, automatic gain through star ground radio-frequency transmissions passage and form radiofrequency signal and accomplish remote measurement and satellite number biography to ground.
The present invention provides a kind of micro-nano satellite telemetry communication integrated receive-transmit system, comprising:
The sending and receiving end is used to receive and dispatch radiofrequency signal, comprises star ground reception antenna, star ground transmitting antenna;
RF front-end module comprises:
Star ground radio-frequency module is used to accomplish the signal transmission between main satellite and the ground; Comprise:
Star ground radio frequency reception channel is used for that the radiofrequency signal that receives is simulated down conversion process and forms intermediate-freuqncy signal;
Star ground radio-frequency transmissions passage is used for the radiofrequency signal that receives simulated to increase to handle frequently forming intermediate-freuqncy signal;
The intermediate frequency baseband signal processing module is used for the said intermediate-freuqncy signal that receives is accomplished analog-to-digital conversion, digital frequency conversion and digital modulation and demodulation; Comprise:
The upward signal processing module through remote control and the transmission of uplink data of facing satellite to the upstream digital intermediate-freuqncy signal with finishing dealing with; The up analog if signal from star ground radio frequency reception channel that receives is carried out analog to digital conversion form the upstream digital intermediate-freuqncy signal; Through digital frequency reducing and be divided into two-way; The up channel of leading up to carries out QPSK demodulation, channel-decoding and protocol processes and obtains line number biography data; Transfer to spaceborne computer through interface and handle, accomplish the number biography of ground to satellite; Another road obtains the observing and controlling vision signal through the PM demodulation; Said observing and controlling vision signal is carried out obtaining sidetone signal and up PCM remote control frame respectively after range tone filtering and the BPSK demodulation; Sidetone signal is delivered to said receive-transmit system down channel, with the synthetic descending PM modulation signal of PCM/PSK telemetered signal; Convert said up PCM remote control frame to remote control command through protocol processes, deliver to spaceborne computer through interface and accomplish remote control;
The downstream signal processing module is through remote measurement and the downlink data transmission of satellite to ground of finishing dealing with to descending digital medium-frequency signal; Obtain two paths of data through interface from spaceborne computer and memory cell; One circuit-switched data is descending PCM telemetry frame; Said descending PCM telemetry frame is carried out descending telemeter channel formatting, chnnel coding and BPSK modulation; Form descending PCM/PSK telemetered signal; After said sidetone signal merging, carry out descending observing and controlling carrier wave PM modulation again, form descending observing and controlling channel modulated signal; Another circuit-switched data is that down line number passes frame, said line number down pass frame through line number down deliver a letter the form layout, line number passes carrier wave QPSK modulation down, forms down the line number modulated signal of delivering a letter; Merge said descending observing and controlling channel modulated signal and the said down line number modulated signal of delivering a letter, through filtering interpolation, numeral increases and forms descending digital medium-frequency signal frequently; Said descending digital medium-frequency signal is formed descending analog if signal through digital-to-analogue conversion send into star ground radio-frequency transmissions passage.
Wherein above-mentioned BPSK is that the abbreviation of Binary Phase Shift Keying is called for short, and means biphase phase shift keying; PM is a kind of signal variation pattern that changes with modulation signal control carrier signal phase; QPSK is that the abbreviation of Quadrature Phase Shift Keying is called for short, and means QPSK.
The integrated receive-transmit system of micro-nano satellite telemetry communication provided by the invention and its implementation; (1) use USB observing and controlling to utilize the principle of software radio with communicating by letter; Adopt the mode of total digitalization; In low-power consumption FPGA (Field-Programmable Gate Array, field programmable gate array) chip, realize.Analog front circuit is only realized the function of up-conversion, down-conversion, power amplifier and LNA.Make the telemetry communication of micro-nano satellite reach requirement low in energy consumption; (2) USB observing and controlling and the coding and decoding of communicating by letter, base band moulding, modulation; All in a chip, realize, do not need extra functional module and chip, reduced the multimode interaction data like this and transmitted required interface number; Increase the integrated level of system, reduced the complexity of whole system; (3) utilize software and radio technique, digitized processing telemetry communication data help on star, moving in the complex environment, improve antijamming capability, have improved reliability.(4) but the regroup that makes full use of software is realized multi-functional.The various functions of unified microwave system all can realize various software function module on hardware platform, realize with software, can be easy to satisfy the multiple demand of different task based on the recombinated characteristic of software.
Embodiment
For the purpose, technical scheme and the advantage that make the embodiment of the invention clearer; To combine the accompanying drawing in the embodiment of the invention below; Technical scheme in the embodiment of the invention is carried out clear, intactly description; Obviously, described embodiment is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the present invention's protection.
Embodiment
Shown in Fig. 1-5, the present invention provides a kind of micro-nano satellite telemetry communication integrated receive-transmit system, comprising: sending and receiving end, RF front-end module, intermediate frequency baseband signal processing module.
The sending and receiving end is used to receive and dispatch radiofrequency signal, comprises between star ground reception antenna 11, star ground transmitting antenna 12 and star antenna 14 between antenna 13, star;
RF front-end module 2 comprises: star ground radio-frequency module 21, star ground radio-frequency module 21; Be used to accomplish the signal transmission between main satellite and the ground; Comprise star ground radio frequency reception channel 211, star ground radio-frequency transmissions passage 212, star ground radio frequency reception channel 211 is used for that the radiofrequency signal that receives is simulated down conversion process and forms intermediate-freuqncy signal; Star ground radio-frequency transmissions passage 212 is used for the radiofrequency signal that receives simulated to increase to handle frequently forming intermediate-freuqncy signal;
The intermediate frequency baseband signal processing module is used for the said intermediate-freuqncy signal that receives is accomplished analog-to-digital conversion, digital frequency conversion and digital modulation and demodulation; The intermediate frequency baseband signal processing module is integrated by remote control module and telemetry module, wherein,
The upward signal processing module through remote control and the transmission of uplink data of facing satellite to the upstream digital intermediate-freuqncy signal with finishing dealing with; The up analog if signal from star ground radio frequency reception channel 211 that receives is carried out analog to digital conversion form the upstream digital intermediate-freuqncy signal; Through digital frequency reducing and be divided into two-way; The up channel of leading up to carries out QPSK demodulation, channel-decoding and protocol processes and obtains line number biography data; Transfer to spaceborne computer through interface and handle, accomplish the number biography of ground to satellite; Another road obtains the observing and controlling vision signal through the PM demodulation; Said observing and controlling vision signal is carried out obtaining sidetone signal and up PCM remote control frame respectively after range tone filtering and the BPSK demodulation; Sidetone signal is delivered to said receive-transmit system down channel, with the synthetic descending PM modulation signal of telemetered signal; Convert said up PCM remote control frame to remote control command through protocol processes, deliver to spaceborne computer through interface and accomplish remote control;
The downstream signal processing module is through remote measurement and the downlink data transmission of satellite to ground of finishing dealing with to descending digital medium-frequency signal; Obtain two paths of data through interface from spaceborne computer and memory cell; One circuit-switched data is descending PCM telemetry frame; Said descending PCM telemetry frame is carried out descending telemeter channel formatting, chnnel coding and BPSK modulation; Form descending PCM/PSK telemetered signal; After said sidetone signal merging, carry out descending observing and controlling carrier wave PM modulation again, form descending observing and controlling channel modulated signal; Another circuit-switched data is that down line number passes frame, said downlink data frame through line number down deliver a letter the form layout, line number passes carrier wave QPSK modulation down, forms down the line number modulated signal of delivering a letter; Merge said descending observing and controlling channel modulated signal and the said down line number modulated signal of delivering a letter, through filtering interpolation, numeral increases and forms descending digital medium-frequency signal frequently; Said descending digital medium-frequency signal is formed descending analog if signal through digital-to-analogue conversion send into star ground radio-frequency transmissions passage 212.
The upward signal processing module comprises analog to digital converter, up telemetry communication IF process module, up protocol process module, control module 34, upstream Interface module.
Analog to digital converter is used for the analog if signal that receives from star ground radio frequency reception channel 211 is carried out analog-to-digital conversion formation upstream digital intermediate-freuqncy signal, is made up of modulus conversion chip and intermediate-frequency filter.
Up telemetry communication IF process module comprises low-converter 351, communication demodulation module, remote control demodulation module.Wherein, low-converter 351 is used for that said upstream digital intermediate-freuqncy signal is carried out down conversion process and forms upstream digital one-level frequency reducing signal.The communication demodulation module is used for that said upstream digital frequency reducing signal is carried out the QPSK demodulation and forms line number and deliver a letter and make frame; Be delivered to up protocol process module; Mainly constitute by QPSK demodulation module 353; Be used for said upstream digital frequency reducing signal number through capturing carrier tracking, time synchronized, judgement, reply out line number and deliver a letter and make frame.The remote control demodulation module carries out the PM demodulation to said upstream digital frequency reducing signal and forms said observing and controlling vision signal; To said observing and controlling vision signal carry out after range tone filtering and the BPSK demodulation respectively said sidetone signal and said up PCM remote control frame, said up PCM remote control frame is passed to up protocol process module; Mainly form by PM demodulation module 355 and BPSK demodulation module 357; PM demodulation module 355 is used for said upstream digital frequency reducing signal is carried out acquisition and tracking; The numeric field demodulation; Extract said observing and controlling vision signal, this observing and controlling vision signal is carried out the range tone Filtering Processing get said sidetone signal and PCM/PSK remote signal; BPSK demodulation module 357 is used for said PCM/PSK remote signal carrier synchronization, time synchronized, judgement, replys out up PCM (pulse code modulation) the remote control frame through chnnel coding.
Up protocol process module is used for the said up PCM remote control frame that receives is handled, and extracts remote control command and gives spaceborne computer; And the last line number that will receive delivers a letter and makes frame handle, and line number passes data and gives said spaceborne computer in the extraction; Mainly form by first protocol process module, first data communication interface and real time remote control interface.First protocol process module; Being used for that said up PCM remote control frame through chnnel coding is carried out the channel-decoding communication format peels off and obtains PCM remote control frame; And said PCM remote control frame handled; Extract direct switch remote control command, deliver to power-supply system, and said up PCM remote control frame is delivered to ancillary equipment; Be used for the said line number that goes up is delivered a letter and made frame carry out the channel-decoding communication format peeling off, line number biography data are delivered to ancillary equipment in extractions.First data communication interface is used to connect said QPSK demodulation module; The real time remote control interface is used to connect said BPSK demodulation module 357.
Control module 34 is used for controlling said analog to digital converter by said spaceborne computer according to the control signal that said remote control command feeds back to said control module, low-converter, communication demodulation module, remote control demodulation module, the action of up protocol process module;
The upstream Interface module is used to connect ancillary equipment, up protocol process module and control mould, comprises spaceborne computer interface 331, memory cell interface 332 and other subsystem interfaces 333.
The downstream signal processing module comprises digital to analog converter, descending telemetry communication IF process module, descending protocol processing module, downstream interface module.
The downstream interface processing module is used to connect ancillary equipment, descending protocol processing module, comprises spaceborne computer interface 331, memory cell interface 332 and other subsystem interfaces 333.
The descending protocol processing module is used for the descending PCM telemetry frame that comes from said spaceborne computer that receives is carried out processing forward to remote measurement modulation module; The following line number that comes from memory cell that receives is passed frame to be handled and is sent to said communication modulation module; Comprise second protocol process module, second data communication interface and real-time telemetry interface; Second protocol process module and first protocol process module are integrated in the protocol processor 321; Be used to receive said descending PCM telemetry frame, carry out being sent to said BPSK modulation module through said real-time telemetry interface after descending telemeter channel formatting, the chnnel coding from said spaceborne computer; The said line number down that is used to receive said memory cell passes frame, and following line number is delivered a letter and is forwarded to the QPSK modulation module through said second data communication interface after form layout, the chnnel coding; Second data communication interface and first data communication interface integrate in data communication interface 322, are used to connect said QPSK modulation module 356; Real-time telemetry interface and real time remote control interface integrate in real time remote control telemetry interface 323, are used to connect said BPSK modulation module 358.
Descending telemetry communication IF process module mainly is made up of remote measurement modulation module, communication modulation module and upconverter 352.The remote measurement modulation module; Be used for that the said descending PCM telemetry frame through the descending protocol processing that receives is carried out BPSK and be modulated to the real-time telemetry subcarrier; And with merge from the isolated sidetone signal of said observing and controlling vision signal, be modulated on the descending observing and controlling carrier wave through PM; Mainly form by BPSK modulation module 358 and PM modulation module 356; BPSK modulation module 358 is used for that the said descending PCM telemetry frame of handling through descending protocol that said second protocol processor sends is carried out the BPSK modulation and obtains the PCM/PSK telemetered signal, said PCM/PSK telemetered signal and said sidetone signal is carried out numeral synthesize; PM modulation module 356; Be used for the digital signal that the synthetic back of above-mentioned numeral forms is modulated to through PM the said descending observing and controlling carrier wave of 4MHz.The communication modulation module is used for that the said line number of handling through descending protocol down that receives is passed frame and carries out QPSK and be modulated to down line number biography carrier wave; Merge said descending observing and controlling carrier wave and pass carrier wave, and form down line of numbers through filtering interpolation and increase the frequency signal with following line number; Mainly constitute, be used for the said following line number biography frame of handling through descending protocol of said second protocol processor transmission is carried out the said biography of the line number down carrier wave that QPSK is modulated to 6MHz by QPSK modulation module 354; And said descending observing and controlling carrier wave and following line number passed carrier wave through closing the road, the completion filtering interpolation is delivered to said digital-to-analogue chip.
Upconverter 352, signal increases the descending digital medium-frequency signal of processing formation frequently to be used for increasing frequently to said line of numbers one-level down;
Digital to analog converter is used for that the descending digital medium-frequency signal that receives is carried out digital-to-analogue conversion and forms descending analog if signal and be sent to star ground radio-frequency transmissions passage 212.
Shown in Fig. 2-5, wherein, analog to digital converter and digital to analog converter are integrated in the D/A converter module 32; Up telemetry communication IF process module and descending telemetry communication IF process module are integrated in the telemetry communication IF process module 35, for ground observing and controlling equipment provide two-way coherent carrier Doppler tracking beacon for ground observing and controlling device tracking, angle measurement, test the speed; Up protocol process module and descending protocol processing module are integrated in the protocol process module 32; Upstream Interface module and downstream interface module are integrated in the interface module 33.QPSK modulation module 354 and QPSK demodulation module 353 are for being integrally formed in the QPSK modulation module in addition; PM modulation module 356 is integrally formed in the PM modulation module with PM demodulation module 355; BPSK modulation module 358 is integrally formed in the BPSK modulation module with BPSK demodulation module 357, and simultaneously, QPSK modulation module, PM modulation module and BPSK modulation module are integrally formed in the modulation module; Integrated degree is higher, practices thrift to take up room and weight.
D/A converter module 32 is made up of A/D (modulus) signal condition module, A/D, D/A (digital-to-analogue) and intermediate-frequency filter.Major function:
(1) D/A converter module 32 receptions are accomplished preliminary treatment to received signal from the analog signal of SMA port by A/D signal condition module, accomplish sampling by A/D again, send in the down conversion module of IF process module;
(2) dateout of up-conversion module in 32 pairs of intermediate frequency processing modules of D/A converter module is accomplished digital-to-analogue conversion by D/A, and by the analog signal of final output 30M intermediate frequency after the intermediate-frequency filter filtering to the SMA port.
Telemetry communication IF process module 35 mainly is made up of upconverter 352, low-converter 351, PM modulation module, BPSK modulation module and QPSK modulation module.Major function:
(1) for ground observing and controlling equipment provide two-way coherent carrier Doppler tracking beacon for ground observing and controlling device tracking, angle measurement, test the speed;
(2) residual carrier in the up intermediate-freuqncy signal of acquisition and tracking, sidetone signal and subcarrier remote signal are extracted in numeric field PM demodulation, and the subcarrier remote signal is offered the BPSK demodulation module;
(3) under the packet telemetry pattern, sidetone signal is forwarded to the downstream signal processing module carries out descending modulation and transfer to the radio-frequency transmissions passage via D/A converter module;
(4) under the PCM telemetry mode, sidetone signal and telemetered signal are carried out descending modulation respectively, and modulated signal is carried out numeral synthesize, transfer to the radio-frequency transmissions passage via D/A converter module;
(5) receive the PSK remote signal of exporting from the USB answering machine, and carry out BPSK demodulation, judgement, channel-decoding, recover PCM remote control frame; Reception is carried out signal source and channel, PSK modulation treatment from the PCM telemetry frame of protocol process module 32, delivers to the PM modulation module;
(6) receive the QPSK number number of delivering a letter of exporting from the medium-frequency receiving and sending signal processing channel, carry out capturing carrier and follow the tracks of, time synchronized, judgement and information are recovered, channel-decoding, recover line number and pass Frame, transfer to protocol process module 32 and handle;
(7) reception is carried out signal source and channel, QPSK modulation treatment after transfer to the radio-frequency transmissions passage by D/A converter module from the source bag of protocol process module 32.
Protocol process module 32 is made up of data communication interface 322, real time remote control telemetry interface 323 and protocol processor 321.Major function:
(1) under the PCM telemetry mode, the PCM remote control frame of demodulation module output is handled, extract direct switch remote control command, deliver to power subsystem, and the remote control frame is delivered to the formation of spaceborne computer CAN EBI.(deliver to real-time command CAN formation and non real-time instruction CAN formation, distinguish according to remote control command and send priority, implement queue management);
(2) under the PCM telemetry mode, the subpackage star ground uplink transmission frame of demodulation module output is communicated form peel off, deliver to the formation of spaceborne computer CAN EBI;
(3) under the PCM telemetry mode, receive PCM telemetry frame from spaceborne computer, communicate the channel format layout after, be forwarded to modulation module;
(4) under the PCM telemetry mode, receive from all kinds of sources of spaceborne computer and memory cell and wrap, communicate the channel format layout after, send to modulation module;
(5) under the packet telemetry pattern, the upper planet ground subpackage transmission frame that demodulation module is exported communicates the channel format processing, delivers to the formation of spaceborne computer CAN bus;
(6) under the packet telemetry pattern, subpackage transmission frame between the star of demodulation module output is communicated channel format handle, deliver to the formation of spaceborne computer CAN bus;
(7) under the packet telemetry pattern, receive star ground transmission frame from management and control computer and memory cell on the star, communicate the channel format layout after, deliver to modulation module;
(8) under the packet telemetry pattern, receive from transmission frame between the star of management and control computer and memory cell on the star, communicate the channel format layout after, deliver to modulation module.
Interface module 33 is made up of spaceborne computer interface 331, memory cell interface 332 and other subsystem interfaces 333.Main accomplish interconnected between intermediate frequency baseband processing module and spaceborne other equipment.
Control module 34 major functions:
(1) operation phase that receives management and control computer on the star is controlled requirement, and the communication system running status is carried out control change and maintenance, comprises radio frequency control and intermediate frequency control two parts function;
(2) set up communication software master control cyclic program, the resource occupation of each software module operation of communication system is coordinated (interruption controls);
(3) transfer of data of communication interface on the star is controlled, comprised the control of CAN bus and LVDS link layer protocol;
(4) set up state of emergency logic, control is implemented in the communication under the state of emergency, observing and controlling according to urgent observing and controlling demand.
Implementation method below in conjunction with Fig. 1-5 pair of integrated receive-transmit system of micro-nano satellite telemetry communication is elaborated.
Comprise two steps, 1) the upward signal treatment step: 2) downstream signal treatment step;
Step 1) mainly comprises following two big steps:
11) carry out power amplification, simulation frequency conversion, the up analog if signal of automatic gain control formation through star ground radio frequency reception channel 211 received RF signals and to it;
12) the up analog if signal from star ground radio frequency reception channel 211 that receives is carried out analog to digital conversion and form the upstream digital intermediate-freuqncy signal; Through digital frequency reducing and be divided into two-way; The up channel of leading up to carries out QPSK demodulation, channel-decoding and protocol processes and obtains line number biography data; Transfer to spaceborne computer through interface and handle, accomplish the number biography of ground to satellite; Another road obtains the observing and controlling vision signal through the PM demodulation; Said observing and controlling vision signal is carried out obtaining sidetone signal and up PCM remote control frame respectively after range tone filtering and the BPSK demodulation; Sidetone signal is delivered to said receive-transmit system down channel, with the synthetic descending PM modulation signal of telemetered signal; Convert said up PCM remote control frame to remote control command through protocol processes, deliver to spaceborne computer through interface and accomplish remote control;
Step 2) mainly comprise following two big steps:
21) obtain two paths of data through interface from spaceborne computer and memory cell; One circuit-switched data is descending PCM telemetry frame; Said descending PCM telemetry frame is carried out descending telemeter channel formatting, chnnel coding and BPSK modulation; Form descending PCM/PSK telemetered signal; After said sidetone signal merging, carry out descending observing and controlling carrier wave PM modulation again, form descending observing and controlling channel modulated signal; Another circuit-switched data is that down line number passes frame, said downlink data frame through line number down deliver a letter the form layout, line number passes carrier wave QPSK modulation down, forms down the line number modulated signal of delivering a letter; Merge said descending observing and controlling channel modulated signal and the said down line number modulated signal of delivering a letter, through filtering interpolation, numeral increases and forms descending digital medium-frequency signal frequently; Said descending digital medium-frequency signal is formed descending analog if signal through digital-to-analogue conversion send into star ground radio-frequency transmissions passage 212.
22) receive said descending analog if signals and it is carried out power amplification, simulation frequency conversion, automatic gain control through star ground radio-frequency transmissions passage 212 and form radiofrequency signal and accomplish remote measurement and satellite number biography to ground.
Wherein step 12) realizes through following three concrete steps:
121) said up analog if signal is sampled through A/D (modulus) chip, get the upstream digital intermediate-freuqncy signal of the over-sampling of 30MHz centre frequency through intermediate frequency filtering;
122) said upstream digital intermediate-freuqncy signal is through 10 times of extractions of digital frequency reducing and CIC data pick-up filter, and being transformed into center frequency point is the multicarrier sampled signal of 2.5MHz;
123) be said center frequency point that the multicarrier sampled signal of 2.5MHz adopts parallel filtering to carry out channel separation, be divided into two-way; To wherein one the tunnel carrying out the QPSK demodulation; Form line number through capturing carrier tracking, time synchronized, judgement and deliver a letter and make frame, and carry out channel-decoding, reply out the said line number that goes up and pass data; Be passed to said spaceborne computer through the interface transfer, the number of accomplishing upward signal passes; The demodulation of PM numeric field is carried out on another road; Extract said observing and controlling vision signal, to this observing and controlling vision signal carry out parallel filtering handle said sidetone signal and PCM/PSK remote signal, said PCM/PSK remote signal is carried out demodulation, channel-decoding; Reply out said up PCM remote control frame; Send into and convert said remote control command to after protocol processor 321 is handled, remote control command is delivered to spaceborne computer, accomplish remote control by the collaborative spaceborne computer of said control module through interface.
Step 21) through realizing with next concrete steps:
211) to said descending PCM telemetry frame carry out descending telemeter channel formatting, chnnel coding, BPSK modulate the PCM/PSK telemetered signal; To said PCM/PSK telemetered signal and said sidetone signal carry out numeral synthetic after; Carry out descending observing and controlling carrier wave PM again and be modulated on the 4MHz carrier wave, form said descending observing and controlling channel modulated signal; Said down line number pass frame through line number down deliver a letter the form layout, line number passes carrier wave QPSK and is modulated to and forms the said line number down modulated signal of delivering a letter on the 6MHz carrier wave down; Merge said descending observing and controlling channel modulated signal and the said down line number modulated signal of delivering a letter; And behind the completion filtering interpolation; On the centre frequency of 30MHz, form analog if signal through Digital Up Convert, give star ground radio-frequency transmissions passage with emission through digital-to-analogue conversion.
Wherein, RF front-end module is mainly accomplished radio-frequency receiving-transmittings such as reception, power amplification, frequency conversion, the automatic gain control operation of radiofrequency signal.Because transmitting power is bigger, and requires receiving sensitivity higher, add that transmitting-receiving works simultaneously, adopt the frequency division mode of operation, dual-mode antenna is separately.Radio frequency reception channel mainly is made up of parts such as LNA, low-converter 351 and AGC.Parts such as the radio-frequency transmissions passage mainly contains upconverter 352, puts in advance, power amplifier are formed.
Radio frequency reception channel and star ground radio frequency reception channel 211 all adopt the receiver of double superheterodyne structure between star.Receiver front end is right after after antenna feed, and the radiofrequency signal of importing is down-converted to the first intermediate frequency fI, utilizes band pass filter that image frequency is blocked in outside the passband, is converted to the second intermediate frequency 30MHz again, passes to baseband processing unit.Radio-frequency transmissions passage 221 is identical with star ground radio-frequency transmissions passage 212 structures between star.Through twice up-conversion the intermediate frequency input is faded to required radiofrequency signal, directly export through the amplifier and the power amplifier of Gain Adjustable.The receive path signal flow is with reference to Fig. 3; The transmission channel signal flow is referring to Fig. 4.
The concrete Digital Signal Processing of data in the intermediate frequency baseband signal processing module is following: at the receiving terminal of intermediate frequency baseband processing module; Analog down through the sampling of AD chip, has obtained the digital medium-frequency signal of the over-sampling of 30MHz centre frequency to the signal of intermediate frequency from RF front-end module.Through 10 times of extractions of Digital Down Convert and CIC data pick-up filter, being transformed into center frequency point is 2.5MHz, sampling intermediate-freuqncy signal.At this moment, the signal of 2.5M center frequency point is divided into two-way, and first via signal is through the QPSK demodulation, after sending into protocol process module 32 and handling, through the interface transfer, accomplishes transfer of data between star; The second road signal demodulates the observing and controlling vision signal through after the PM demodulation, and continues the BPSK demodulation, obtains remote signal, sends into protocol process module 32, and passes to the 34 completion remote controls of control corresponding module through interface module 33.
At the transmitting terminal of intermediate frequency baseband signal processing module, at first through the interface telemetry, through being modulated on the real-time telemetry subcarrier after the BPSK modulation, and with merge from the isolated range tone signal of vision signal.The signal that two-way merges is modulated on the 4MHz carrier wave through PM.At this moment also have another road to be modulated to the QPSK communication data on the 6MHz carrier wave.Process is closed the road again, and after accomplishing filtering interpolation, this signal digital is upconverted on the centre frequency of 30MHz.Through digital-to-analogue conversion, give RF front-end module at last with emission.
What should explain at last is: above embodiment is only in order to explaining technical scheme of the present invention, but not to its restriction; Although with reference to previous embodiment the present invention has been carried out detailed explanation, those of ordinary skill in the art is to be understood that: it still can be made amendment to the technical scheme that aforementioned each embodiment put down in writing, and perhaps part technical characterictic wherein is equal to replacement; And these are revised or replacement, do not make the spirit and the scope of the essence disengaging various embodiments of the present invention technical scheme of relevant art scheme.