CN107359900B - A kind of modem suitable for overlength distance scattering link - Google Patents
A kind of modem suitable for overlength distance scattering link Download PDFInfo
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- CN107359900B CN107359900B CN201710627692.6A CN201710627692A CN107359900B CN 107359900 B CN107359900 B CN 107359900B CN 201710627692 A CN201710627692 A CN 201710627692A CN 107359900 B CN107359900 B CN 107359900B
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- 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
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7073—Synchronisation aspects
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
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- Synchronisation In Digital Transmission Systems (AREA)
Abstract
The invention discloses a kind of modems suitable for overlength distance scattering link, it is related to the scatter communication system that communications field communication distance is remote, frequency deviation is serious, signal-to-noise ratio is extremely low.It is made of components such as modulator, demodulator, intermediate frequency amplifier, auxiliary multiplexer, auxiliary coupler, rubidium clock units.The present invention uses the channel decoding technology based on CCSDS standard, so that wireless communication system is suitable for the scatter channel environment of Arctic ice area, guarantees the high reliability transport of business.The present invention additionally uses the demodulation method of secondary spread spectrum plus pilot tone, guarantees the low threshold level of equipment, realizes equipment is synchronous under big frequency deviation state quick foundation and holding.Especially suitable under Rayleigh deep fade channel condition, the high quality of business, high reliability transport on long distance scatter communication link.
Description
Technical field
The present invention relates to one of communications fields to be suitable for the modem that overlength distance scatters link, especially suitable for
It solves the problems, such as that overlength distance scatter communication link path loss is big, frequency deviation is serious, signal-to-noise ratio is extremely low, resists by bringing at a distance
Channel condition deteriorate, promoted communication reliability.
Background technique
Existing scatter modem commonly scatters modulator when working under overlength distance scattering link condition
High performance coding mode is not used, is not effective against communication path loss；Demodulator mostly uses greatly differential ference spiral, resists
Deviation capability is strong, but demodulation performance is poor, especially in the case where scattering variable-parameter channel overlength distance link, due to channel SNRs pole
Low, demodulator synchronizing capacity is poor, and usually step-out even chain rupture, seriously affects communication efficiency and reliability.Only by increase day
The hardware costs such as line mouth face and power amplifier transmission power cause overhead seriously to increase to complete communication.
Summary of the invention
It is proposed present invention aims at the shortcoming avoided in above-mentioned background technique a kind of scattered suitable for overlength distance
Penetrate the modem of link.The present invention uses the channel decoding technology based on CCSDS standard, the 1/4Turb of low bit- rate
Code is applied to scatter communication system, enables a system to the scatter channel environment suitable for Arctic ice area, guarantees that the height of business can
By property transmission.The present invention additionally uses the demodulation method of secondary spread spectrum plus pilot tone, effectively to solve overlength distance scattering link frequency
Partially serious problem guarantees that equipment realizes that the synchronous of quick high accuracy is established and kept under severe channel conditions.It is particularly suitable
In under Rayleigh deep fade channel condition, the high quality of business, high reliability transport on long distance scatter communication link.
The object of the present invention is achieved like this:
It is a kind of suitable for overlength distance scattering link modem, it include auxiliary multiplexer 3, auxiliary coupler 4, in
Audio amplifier 5, rubidium clock unit 6 further include modulator 1 and demodulator 2；
In transmitting terminal: auxiliary multiplexer 3 receives the business datum and business clock of external business terminal input, carries out business
Multiple connection, and by after multiple connection information code current and symbol clock be sent into modulator 1；Modulator 1 is using symbol clock to information code current
Base-Band Processing is carried out, and carries out carrier modulation, exports modulated medium frequency signal；
In receiving end: intermediate frequency amplifier 5 receives the demodulation intermediate-freuqncy signal of external radio frequency unit input, to demodulation intermediate-freuqncy signal
Intermediate frequency amplification is carried out, and amplified demodulation intermediate-freuqncy signal is sent into demodulator 2；Demodulator 2 is to the amplified solution received
It adjusts intermediate-freuqncy signal to carry out A/D transformation, carries out demodulation process after being converted into digital signal, and the signal feeding after demodulation process is auxiliary
Help coupler 4；Auxiliary coupler 4 by the signal after the demodulation process received carry out business tap to obtain service data information and
Business clock, and the service data information tapped out and business clock are sent respectively to external output port；Rubidium clock unit 6 is used for
High-precision clock reference signal is provided to modulator 1, demodulator 2, auxiliary multiplexer 3 and auxiliary coupler 4.
Wherein, the modulator 1 includes coding framing module 7, two-stage spread spectrum module 8, molding modulation module 9, D/A change
Change the mold block 10, mixing and filtering module 11 and local oscillator generation module 12；Framing module 7 is encoded by the information code after the multiple connection received
Coding framing fluently is carried out with symbol clock, the information code current for encoding framing is exported to two-stage spread spectrum module 8；Two-stage spread spectrum mould
Block 8 will spread the information code current for encoding framing, and the information code current after spread spectrum is exported to molding modulation module 9；Pattern
The Turbo code for being 1784 for 1/4 code rate, weaving length based on CCSDS standard；Communication performance is influenced for confrontation frequency deviation, is adopted
It is connected to save FPGA hardware resource using two-stage spread spectrum with spread spectrum system, coded signal is spread to 16384 times, is sent
To molding modulation module 9；It forms modulation module 9 and the information code current after spread spectrum is subjected to square wave base band shaping, and carry out BPSK tune
System forms digital baseband signal, is sent into D/A conversion module 10；Digital baseband signal is converted into simulation letter by D/A conversion module 10
Number, and it is sent into mixing and filtering module 11；Local oscillator generation module 12 generates 70M using the clock reference signal that rubidium clock unit 6 provides
Intercarrier signal, and it is sent into mixing and filtering module 11；Mixing and filtering module 11 believes the baseband signal of input and IF carrier
It number is mixed, after bandpass filtering, exports modulated medium frequency signal.
Wherein, demodulator 2 is mentioned including Digital Down Converter Module 13, two-stage despreading module 14, flywheel synchronization module 15, pilot tone
Carry module 16, product module 17, frame synchronization module 18 and decoding judging module 19；
Digital Down Converter Module 13 receives amplified demodulation intermediate-freuqncy signal and clock reference signal, to amplified demodulation
Intermediate-freuqncy signal carries out Digital Down Convert, is converted to baseband digital signal, and is sent into two-stage despreading module 14；Two-stage de-spreads module 14
Concatenated two-stage is carried out to the baseband digital signal of input and despreads signal of the processing generation containing bit synchronization information, and is sent respectively
Enter flywheel synchronization module 15 and product module 17；Flywheel synchronization module 15 extracts optimum sampling value using " flywheel " synchronized algorithm,
Optimum sampling value feeding pilot tone is mentioned and carries module 16；So-called " flywheel " synchronized algorithm is exactly by the maximum position of relevant peaks come really
The phase for the chip clock that fixed high clock divides；Pilot tone, which mentions, carries module 16 using bit synchronization information, is mentioned by identification pilot tone
Carrier wave is taken, carrier synchronization is completed, recovers carrier signal, carrier signal is sent into product module 17；Product module 17 will contain
The signal of bit synchronization information is multiplied with carrier signal, recovers figure information, and be sent into frame synchronization module 18；Frame synchronization module 18
" information frame " that has synchronized is sent into decoding judging module 19 by the frame synchronization that signal is completed according to eye figure information；Decoding judgement mould
Block 19 carries out Turbo code Max-Log-Map iterative decoding to " information frame " to be decoded, and makes decisions to the information after decoding
Output.
The present invention has the following advantages over the background art:
1. the modulator 1 that the present invention uses, using the coding mode and two of the low bit- rate Turbo based on CCSDS standard
The technology that grade spread spectrum combines, wherein the improvement of relatively existing scatter communication modulator coding mode is so that the reception of system is clever
Sensitivity and channel gain improve, and the reception ability of small-signal are enhanced, so that scattering system is in the case where signal-to-noise ratio is extremely low
It can complete the crucial reliable transmission for accusing information；Using spread spectrum so that the anti-deviation capability of this modem is strong, second level spread spectrum
Under identical spread spectrum multiple, opposite single is spread, and logical resource used in saving-algorithm, hardware realization is simple, second level spread spectrum
Technical system overcomes signal under the conditions of Arctic ice area and receives the problem for synchronizing difficulty.
2. the demodulator 2 that the present invention uses, the carrier extract scheme combined using two-stage despreading and flywheel synchronization, flywheel
It is synchronous with respect to the background art used in directly filter synchronization scheme, synchronous to establish fast, synchronization accuracy is high, logical with existing scattering
The reception scheme of letter demodulator is compared, and the program is able to solve asking under overlength distance scatter channel out of frame even chain rupture
Topic.
Detailed description of the invention
Fig. 1 is electrical schematic block diagram of the present invention.
Fig. 2 is the electrical schematic diagram of 1 embodiment of modulator of the present invention.
Fig. 3 is the electrical schematic diagram of 2 embodiment of demodulator of the present invention.
Specific embodiment
Referring to figs. 1 to Fig. 3, the present invention is amplified by modulator 1, demodulator 2, auxiliary multiplexer 3, auxiliary coupler 4, intermediate frequency
Device 5 and rubidium clock unit 6 form.Fig. 1 is electrical schematic block diagram of the invention, and embodiment presses Fig. 1 connection line.
Referring to Fig.1, in transmitting terminal: auxiliary multiplexer 3 receives the business datum and business clock of external business terminal input,
Carry out business multiple connection, and by after multiple connection information code current and symbol clock be sent into modulator 1；Modulator 1 utilizes symbol clock pair
Information code current carries out Base-Band Processing, and carries out carrier modulation, exports modulated medium frequency signal E.In receiving end: intermediate frequency amplifier 5 connects
The demodulation intermediate-freuqncy signal F for receiving the input of external radio frequency unit carries out intermediate frequency amplification to signal F, and amplified intermediate-freuqncy signal is sent
Enter demodulator 2；Demodulator 2 carries out A/D transformation to the intermediate-freuqncy signal received, carries out demodulation process after being converted into digital signal,
And signal is sent into auxiliary coupler 4 by treated；It assists coupler 4 that the signal received is carried out business tap, and will divide
The service data information D and business clock C picked out is sent to external output port；Rubidium clock unit 6 is to modulator 1, demodulator 2, auxiliary
Multiplexer 3, auxiliary coupler 4 is helped to provide high-precision 10M clock reference signal.
Fig. 2 is the electrical schematic diagram of 1 embodiment of modulator of the present invention, referring to Fig. 2, modulator 1 include coding framing module 7,
Two-stage spread spectrum module 8, molding modulation module 9, D/A conversion module 10, mixing and filtering module 11 and local oscillator generation module 12；Coding
Information code current after received multiple connection is carried out coding framing by framing module 7, and pattern is 1/4 yard based on CCSDS standard
Rate, the Turbo code that weaving length is 1784；Communication performance is influenced for confrontation frequency deviation, using spread spectrum system, in order to save FPGA
Hardware resource, two-stage spread spectrum module 8 are connected using two-stage spread spectrum, coded signal are spread to 16384 times, are sent to molding and are modulated
Module 9；It forms modulation module 9 and code stream after spread spectrum is subjected to square wave base band shaping, and carry out BPSK modulation；Modulated number base
Band signal passes through D/A conversion module 10, is converted into analog signal by digital signal, and be sent into mixing and filtering module 11；Local oscillator is raw
70M intercarrier signal is generated using the high precision clock reference signal that rubidium clock unit provides at module 12, and is sent into mixing filter
Wave module 11；The two paths of signals of input is mixed by mixing and filtering module 11, and after bandpass filtering, output modulated medium frequency is defeated
Signal E out.
Fig. 3 is the electrical schematic diagram of 2 embodiment of demodulator of the present invention, and referring to Fig. 3, the demodulator 2, which includes that number is lower, to be become
Frequency module 13, two-stage despreading module 14, flywheel synchronization module 15, pilot tone mention and carry module 16, product module 17, frame synchronization module 18
With decoding judging module 19；The input of Digital Down Converter Module 13 is that the amplified received IF signal of intermediate frequency and reference clock are believed
Number, Digital Down Convert is carried out to 70M received IF signal, is translated the signals into as baseband digital signal, and is sent into two-stage despreading
Module 14；Two-stage despreading module 14 inputs the concatenated two-stage of progress to it and despreads processing, and output is contained bit synchronization information
Signal be respectively fed to flywheel synchronization module 15 and product module 17；Flywheel synchronization module 15 is mentioned using " flywheel " synchronized algorithm
Optimum sampling value is taken, so-called " flywheel " synchronized algorithm is exactly the code for determining high clock by the maximum position of relevant peaks and dividing
The phase of first clock；Pilot tone, which mentions, carries module 16 using the optimum sampling value of flywheel synchronization module output, is mentioned by identification pilot tone
Carrier wave is taken, carrier synchronization is completed, recovers carrier signal；Product module 17 two-stage is de-spread after signal and extraction carrier wave letter
Number be multiplied, recover figure information, and be sent into frame synchronization module；Frame synchronization module 18 is same using the frame that eye figure information completes signal
" information frame " that has synchronized then is sent into decoding judging module 19 by step；Decoding judging module 19 treats decoding information progress
Turbo code Max-Log-Map iterative decoding, and output is made decisions to the information after decoding.
All digital signal processings of the present invention are carried out in the fpga chip EP3SE80F1152I4N of altera corp
Hardware realization.It is 280mm, width 110mm that the present invention, which is integrated in a block length, highly in the printed board of 10mm.
Claims (2)
1. it is a kind of suitable for overlength distance scattering link modem, it include auxiliary multiplexer (3), auxiliary coupler (4),
Intermediate frequency amplifier (5), rubidium clock unit (6), it is characterised in that: further include modulator (1) and demodulator (2)；
Transmitting terminal: auxiliary multiplexer (3) receives the business datum and business clock of external business terminal input, and it is multiple to carry out business
Connect, and by after multiple connection information code current and symbol clock be sent into modulator (1)；Modulator (1) is using symbol clock to information code
Stream carries out Base-Band Processing, and carries out carrier modulation, exports modulated medium frequency signal；
Receiving end: intermediate frequency amplifier (5) receives the demodulation intermediate-freuqncy signal of external radio frequency unit input, carries out to demodulation intermediate-freuqncy signal
Intermediate frequency amplification, and amplified demodulation intermediate-freuqncy signal is sent into demodulator (2)；Demodulator (2) is to the amplified solution received
It adjusts intermediate-freuqncy signal to carry out A/D transformation, carries out demodulation process after being converted into digital signal, and the signal feeding after demodulation process is auxiliary
Help coupler (4)；Signal after the demodulation process received is carried out business and taps to obtain business datum letter by auxiliary coupler (4)
Breath and business clock, and the service data information tapped out and business clock are sent respectively to external output port；Rubidium clock unit
(6) for providing high-precision clock reference to modulator (1), demodulator (2), auxiliary multiplexer (3) and auxiliary coupler (4)
Signal；
Wherein, demodulator (2) includes Digital Down Converter Module (13), two-stage despreading module (14), flywheel synchronization module (15), leads
Frequency, which mentions, carries module (16), product module (17), frame synchronization module (18) and decoding judging module (19)；
Digital Down Converter Module (13) receives amplified demodulation intermediate-freuqncy signal and clock reference signal, in amplified demodulation
Frequency signal carries out Digital Down Convert, is converted to baseband digital signal, and is sent into two-stage despreading module (14)；Two-stage de-spreads module
(14) concatenated two-stage is carried out to the baseband digital signal of input and despreads signal of the processing generation containing bit synchronization information, and divided
It Song Ru not flywheel synchronization module (15) and product module (17)；Flywheel synchronization module (15) extracts position using " flywheel " synchronized algorithm
Optimum sampling value feeding pilot tone is mentioned and carries module (16) by optimum sampling value；Pilot tone, which mentions, carries module (16) using optimum sampling value, leads to
Identification pilot tone is crossed to extract carrier wave, carrier synchronization is completed, recovers carrier signal, carrier signal is sent into product module (17)；
Signal containing bit synchronization information is multiplied by product module (17) with carrier signal, recovers figure information, and be sent into frame synchronization
Module (18)；Frame synchronization module (18) completes the frame synchronization of signal according to eye figure information, and " information frame " that has synchronized feeding is translated
Code judging module (19)；Decoding judging module (19) carries out Turbo code Max-Log-Map iteration to " information frame " to be decoded and translates
Code, and output is made decisions to the information after decoding.
2. a kind of modem suitable for overlength distance scattering link according to claim 1, it is characterised in that described
Modulator (1) include coding framing module (7), two-stage spread spectrum module (8), molding modulation module (9), D/A conversion module
(10), mixing and filtering module (11) and local oscillator generation module (12)；Framing module (7) are encoded by the information after the multiple connection received
Code stream carries out coding framing using symbol clock, and the information code current for encoding framing is exported to two-stage spread spectrum module (8)；Two-stage expands
Frequency module (8) will spread the information code current for encoding framing, and the information code current after spread spectrum is exported to molding modulation module
(9)；It forms modulation module (9) and the information code current after spread spectrum is subjected to square wave base band shaping, and carry out BPSK and modulate to form number
Baseband signal is sent into D/A conversion module (10)；Digital baseband signal is converted into analog signal by D/A conversion module (10), and is sent
Enter mixing and filtering module (11)；Local oscillator generation module (12) generates intermediate frequency using the clock reference signal that rubidium clock unit (6) provide
Carrier signal, and it is sent into mixing and filtering module (11)；Mixing and filtering module (11) believes the baseband signal of input and IF carrier
It number is mixed, after bandpass filtering, exports modulated medium frequency signal.
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| CN201710627692.6A CN107359900B (en) | 2017-07-28 | 2017-07-28 | A kind of modem suitable for overlength distance scattering link |
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| CN108736958B (en) * | 2018-05-21 | 2021-03-30 | 电子科技大学 | UAT receiving system suitable for satellite-borne environment |
| CN109412632B (en) * | 2018-11-27 | 2019-10-29 | 中国电子科技集团公司第五十四研究所 | A kind of high-speed frequency-hopping transmitting-receiving communication device based on distortion adaptive |
| CN110602018B (en) * | 2019-09-19 | 2022-02-22 | 中国电子科技集团公司第五十四研究所 | Digital frequency correcting device of compatible ultra-low speed scattering communication system |
| CN110971557B (en) * | 2019-11-26 | 2023-05-26 | 阳光电源股份有限公司 | Carrier synchronization method and system for parallel operation of multiple converters |
| CN111060868B (en) * | 2020-03-16 | 2020-07-03 | 南京万自联电子科技有限公司 | Broadband wireless communication and distance measurement system and method thereof |
| CN111313895B (en) * | 2020-03-30 | 2023-03-28 | 中国电子科技集团公司第五十四研究所 | System multi-reference-source multi-clock accurate time-frequency synthesis method |
| CN113541728B (en) * | 2021-06-29 | 2022-06-17 | 中国人民解放军国防科技大学 | Method, system and medium for guided acquisition of short code signal to long code signal |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101789810A (en) * | 2010-02-01 | 2010-07-28 | 北京大学 | Minimum mean-square error two-stage spread spectrum OFDM self-adaptive code distribution method and system |
| CN202261372U (en) * | 2011-09-29 | 2012-05-30 | 中国电子科技集团公司第五十四研究所 | Es layer and meteor trail mixed mode communication modem |
| CN103888166A (en) * | 2013-11-20 | 2014-06-25 | 中国电子科技集团公司第五十四研究所 | Co-spectrum transmission modulation and demodulation device for scatter communication |
| CN104378323A (en) * | 2014-12-03 | 2015-02-25 | 中国电子科技集团公司第五十四研究所 | Low-speed modem on basis of FFT (fast Fourier transform) frequency adjustment algorithm |
| CN106357325A (en) * | 2016-11-04 | 2017-01-25 | 中国电子科技集团公司第五十四研究所 | High-order multi-dimensional spread spectrum modulator, high-order multi-dimensional dispreading demodulator and spectrum spreading device |
-
2017
- 2017-07-28 CN CN201710627692.6A patent/CN107359900B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101789810A (en) * | 2010-02-01 | 2010-07-28 | 北京大学 | Minimum mean-square error two-stage spread spectrum OFDM self-adaptive code distribution method and system |
| CN202261372U (en) * | 2011-09-29 | 2012-05-30 | 中国电子科技集团公司第五十四研究所 | Es layer and meteor trail mixed mode communication modem |
| CN103888166A (en) * | 2013-11-20 | 2014-06-25 | 中国电子科技集团公司第五十四研究所 | Co-spectrum transmission modulation and demodulation device for scatter communication |
| CN104378323A (en) * | 2014-12-03 | 2015-02-25 | 中国电子科技集团公司第五十四研究所 | Low-speed modem on basis of FFT (fast Fourier transform) frequency adjustment algorithm |
| CN106357325A (en) * | 2016-11-04 | 2017-01-25 | 中国电子科技集团公司第五十四研究所 | High-order multi-dimensional spread spectrum modulator, high-order multi-dimensional dispreading demodulator and spectrum spreading device |
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