CN103354468A - L-band upconverter and upconversion method in bandwidth of 1.2GHz - Google Patents
L-band upconverter and upconversion method in bandwidth of 1.2GHz Download PDFInfo
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- CN103354468A CN103354468A CN2013102927864A CN201310292786A CN103354468A CN 103354468 A CN103354468 A CN 103354468A CN 2013102927864 A CN2013102927864 A CN 2013102927864A CN 201310292786 A CN201310292786 A CN 201310292786A CN 103354468 A CN103354468 A CN 103354468A
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Abstract
The invention relates to an L-band upconverter in the bandwidth of 1.2GHz, comprising an input interface, an emitter end, an intermediate-frequency bandwidth selection module, a first mixer, a filter, a second mixer, a radio frequency amplifier, a first local oscillator connected with the first mixer and a second local oscillator connected with the second mixer, wherein the intermediate-frequency bandwidth selection module, the first mixer, the filter, the second mixer and the radio frequency amplifier are successively connected in series. The invention also relates to an L-band upconversion method in the bandwidth of 1.2GHz. According to the L-band upconverter and upconversion method in the bandwidth of 1.2GHz of the invention, 70MHz modulation signals in the bandwidth of 36MHz and 140MHz modulation signals in the bandwidth of 72MHz are compatible, so that emission covers the whole frequency range from 950MHz to 2150MHz which is commonly used in satellite communication, thereby enabling a system to be strongly compatible, and reducing the cost.
Description
Technical field
The invention belongs to satellite communication field, relate to L-band upconverter and the up-conversion implementation method of a kind of bandwidth 1.2GHz.
Background technology
In satellite communication, the modulation signal that modulator in the satellite ground emission system produces is the emission that signal frequency or signal strength signal intensity all are not suitable for satellite antenna, need the satellite upconverter that the modulation signal that modulator produces is processed, the radiofrequency signal of the L-band frequency of the suitable emission that is converted to, and the radiofrequency signal of this frequency range amplified processing, to reach the frequency converter input requirements of final-stage power amplifier or other frequency ranges, then be emitted to satellite repeater through satellite antenna.
L-band is 950-2150 mhz frequency section, at present, the satellite upconverter of most of L-bands all can only cover the bandwidth of hundreds of million in 950MHz～2150MHz, general only carry out single processing for the modulation signal of 70MHz or 140MHz, cause modulation is connected with multiple satellite reception headend equipment inconvenient, system compatibility is poor, the cost increase.
Summary of the invention
Narrow for overcoming in the prior art upconverter bandwidth range, as can only to process single modulation signal technological deficiency, the present invention discloses L-band upconverter and the up-conversion implementation method of a kind of bandwidth 1.2GHz.
The L-band upconverter of bandwidth 1.2GHz of the present invention, comprise input interface and transmitting terminal, and be connected to emission of radio frequency signals path between input interface and the transmitting terminal, it is characterized in that, described emission of radio frequency signals path comprises intermediate-frequency bandwidth selection module, the first frequency mixer, filter, the second frequency mixer and the radio frequency amplifier of successively series connection; Also comprise the first local oscillator that is connected with the first frequency mixer, the second local oscillator that is connected with the second frequency mixer;
The output frequency of described the first local oscillator and the second local oscillator can be selected to regulate, and described intermediate-frequency bandwidth selects module to be used for input signal is carried out the subchannel gating.
Preferably, also be connected with the radio-frequency channel between described radio frequency amplifier and the transmitting terminal and select module, described radio-frequency channel selects module that input signal is carried out segmentation output amplification.
Preferably, described radio-frequency channel selects module to comprise the output channel that three passband start-stop frequencies are connected continuously, each output channel bandwidth 400 megahertz.
Further, described radio-frequency channel is selected also to be connected with the program control attenuation module of the radio frequency amplifier output signal being carried out amplitude adjusted between module and the radio frequency amplifier output.
Preferably, again output after the output one of selected in module, the first frequency mixer at least of described intermediate-frequency bandwidth also is connected with amplifier output signal is amplified.
Preferably, described the first local oscillator and/or the second local oscillator are fractional phase locked loop formula frequency synthesis oscillator.
Preferably, the output frequency of described the first local oscillator is set and is made the output signal frequency of the first frequency mixer greater than 2150MHz.
Preferably, described the first local oscillator and the second local oscillator are positioned at central authorities, and all the other module distribution are in the first local oscillator and the second local oscillator periphery
The L-band up-conversion implementation method of bandwidth 1.2GHz comprises the steps:
Step 1. pair input signal carries out the subchannel gating.
Step 2. pair gating signal and First vibration frequency carry out the mixing first time and obtain the first mixed frequency signal;
Step 3. pair the first mixed frequency signal carries out filtering, and filtered signal and the second local frequency are carried out the mixing second time and obtained the second mixed frequency signal;
Carry out segmentation after step 4. the second mixed frequency signal amplifies and export the transmitting terminal emission to.
Preferably, in the described step 2 the first mixed frequency signal frequency greater than 2150 megahertzes.
Adopt L-band upconverter and the up-conversion implementation method of bandwidth 1.2GHz of the present invention, the modulation signal of compatible 70MHz and two kinds of 36MHz of 140MHz and 72MHz bandwidth, so that modulator can be preferably and the use that is connected of multiple satellite launch headend equipment, the decision design of adopting the radio-frequency channel to select, can make the emission covering frequence comprise the whole frequency range of L-band 950MHz～2150MHz commonly used in the satellite communication, so that there is very strong compatibility in system, reduce cost.
Description of drawings
Fig. 1 illustrates a kind of embodiment schematic diagram of L-band upconverter of bandwidth 1.2GHz of the present invention;
Fig. 2 illustrates a kind of module placement mode of L-band upconverter schematic diagram of bandwidth 1.2GHz of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in further detail.
The L-band upconverter of bandwidth 1.2GHz, comprise input interface and transmitting terminal, and be connected to emission of radio frequency signals path between input interface and the transmitting terminal, and it is characterized in that, described emission of radio frequency signals path comprises that the intermediate-frequency bandwidth of successively series connection selects module, the first frequency mixer.Filter, the second frequency mixer and radio frequency amplifier; Also comprise the first local oscillator that is connected with the first frequency mixer, the second local oscillator that is connected with the second frequency mixer;
The output frequency of described the first local oscillator and the second local oscillator can be selected to regulate, and described intermediate-frequency bandwidth selects module to be used for input signal is carried out the subchannel gating.
Take satellite communication frequency band commonly used at present as example, external modulator is 70MHz or 140MHz with frequency, occupied bandwidth is respectively 36MHz or the 72MHz modulation signal is input to intermediate-frequency bandwidth selection module by input interface, and intermediate-frequency bandwidth selects module to set corresponding bandwidth channel and receive modulation signal for it according to signal frequency.It is starting point adjustable filter all of a bandwidth that intermediate-frequency bandwidth selects module actual, by changing starting point and the terminal point of pass band width, changes centre frequency and the width of bandwidth, to adapt to different modulation signals.
Upconverter is the equipment that the frequency of modulation signal is risen to signal frequency by the up-conversion mode radio frequency band emission, and the basic principle of up-conversion is to utilize frequency mixer that signal is carried out frequency conversion.Among the present invention, adopt two-stage mixing mode to realize to the up-conversion of modulation signal.
Select 70 or 140MHz intermediate-freuqncy signal of module input at first to enter the first frequency mixer from intermediate-frequency bandwidth, the first local oscillator and intermediate-freuqncy signal mixing realize the frequency addition, the intermediate-freuqncy signal frequency is risen, realize for the first time mixing, the first mixed frequency signal that obtains after the mixing for the first time enters the second frequency mixer by filter after with clutter attenuation, the second local oscillator and filtered the first mixed frequency signal mixing, obtain the second mixed frequency signal, the frequency of the second mixed frequency signal is determined by the frequency of the second local oscillator and the first mixed frequency signal.By setting the frequency of first, second local oscillator, can obtain the second mixed frequency signal frequency that needs.The second mixed frequency signal can directly be launched by transmitting terminal after through radio frequency amplifier signal being amplified.
The satellite L-band is contained the 1.2G bandwidth from 950MHz to 2150MHz, the people in Amplifier Design field knows, the bandwidth that the optimum range that amplifier amplifies signal covers is limited, even so-called wide-band amplifier, best amplification performance also can only be embodied in tens to up to a hundred million bandwidth range, and at the extraneous signal of amplifier bandwidth, or multiplication factor is low, introduce signal to noise ratio and increase, all cause amplification performance to can not show a candle to the interior signal of bandwidth range.
Wide for solving satellite L-band coverage, signal is difficult to the technical problem that full bandwidth amplifies, the present invention has preferably increased the radio-frequency channel and has selected module between radio frequency amplifier and transmitting terminal, the radio-frequency channel selects module that input signal is carried out segmentation output amplification, and so-called segmentation refers to that the frequency according to input signal is divided into the frequency band of several linkings.
1.2G bandwidth take 950MHz to 2150MHz is example, the radio-frequency channel selects module that the filter that 950-1350MHz, 1350-1750MHz, three bandwidth of 1750-2150MHz are 400MHz can be set, each filter is to there being an amplifier, the best input signal of amplifier amplifies bandwidth and overlaps with the pass band width of filter or comprise the filter passband bandwidth, for example to the filter of 950-1350MHz, the best input signal of the amplifier that its output connects amplifies bandwidth should comprise this frequency range of 950-1350MHz.The bandwidth trisection is provided with is beneficial to design of filter, and reduce follow-up segmentation Amplifier Design difficulty, make each amplifier in the 400MHz bandwidth, realize preferably enlarging function.
Preferably can select to increase between the module program control attenuation module at radio frequency amplifier and radio-frequency channel, program control attenuation module is amplitude regulating circuit, output signal to radio frequency amplifier is regulated, make signal level after overregulating satisfy the level demand of subsequent conditioning circuit, program control attenuation module can be operational amplifier or level shifting circuit etc.For example the radio frequency amplifier output signal level is-15 to 30V, and the voltage range that follow-up circuit can be accepted is between-10 to 10V, then program control attenuator circuit is adjusted to-10 to 10V with the signal level of input from-15 to 30V, and the frequency of signal itself, waveforms etc. do not change.
Intermediate-frequency bandwidth selects the output of the modules such as module, the first frequency mixer can connect amplifier, with after output signal is amplified in advance to subsequent module, to overcome because decay and distortion that cable run distance or interference bring.The first and second local oscillators can adopt fractional phase locked loop formula frequency synthesis mode (PLL-phase Locked Loop), make the frequency of oscillation of local oscillator and amplitude precision high, and good stability also can be realized less frequency step.
The effect of the first frequency mixer and the second frequency mixer is that modulation signal is carried out secondary mixing, and wherein the carrier signal of the first local oscillator generation and the modulation signal after the amplification carry out the mixing first time and form the first mixed frequency signal.Among the present invention, the first mixed frequency signal preferably is set to greater than 2150MHz, with the first mixed frequency signal set of frequency outside the scope of output bandwidth 950-2150MHz, can guarantee preferably to export like this performance of frequency range 950MHz～2150MHz, this frequency should not be too high, it is 2250MHz that the first mixed frequency signal frequency for example can be set, and namely can not cause the interference in the signalling channel, has reduced again the design difficulty of the first local oscillator.For example to the modulation signal of 70 MHz, be 2320 MHz with the set of frequency of the first local oscillator, the frequency of the first mixed frequency signal that then obtains is 2320-70=2250 MHz.
The L-band upconverter of bandwidth 1.2GHz of the present invention when layout, preferably is arranged in the pcb board middle position with described the first local oscillator and the second local oscillator, and all the other module distribution are in the first local oscillator and the second local oscillator periphery.The first local oscillator and the second local oscillator belong to nucleus module of the present invention, all have multiple signals mutual with modules, therefore with its preferred arrangements in the centre position, make things convenient for signal lead.
Corresponding said apparatus the invention discloses the L-band up-conversion implementation method of a kind of bandwidth 1.2GHz, comprises the steps:
Step 1. pair input signal carries out the subchannel gating.
Step 2. pair gating signal and First vibration frequency carry out the mixing first time and obtain the first mixed frequency signal;
Step 3. pair the first mixed frequency signal carries out filtering, and filtered signal and the second local frequency are carried out the mixing second time and obtained the second mixed frequency signal;
Carry out segmentation after step 4. the second mixed frequency signal amplifies and export the transmitting terminal emission to.
Preferably, the signal frequency in the described step 2 after for the first time mixing is greater than the upper limit of L-band, namely greater than 2150 megahertzes.To reduce the first mixed frequency signal input L-band signal is disturbed.
Adopt L-band upconverter and the up-conversion implementation method of bandwidth 1.2GHz of the present invention, the modulation signal of compatible 70MHz and two kinds of 36MHz of 140MHz and 72MHz bandwidth, so that modulator can be preferably and the use that is connected of multiple satellite launch headend equipment, the decision design of adopting the radio-frequency channel to select, can make the emission covering frequence comprise the whole frequency range of L-band 950MHz～2150MHz commonly used in the satellite communication, so that there is very strong compatibility in system, reduce cost.
The software module that the method that the disclosed embodiments are described among the present invention or the step of algorithm can directly use hardware, processor to carry out, perhaps the combination of the two is implemented.Software module can place the storage medium of any other form known in random asccess memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable ROM, register, hard disk, moveable magnetic disc, CD-ROM or the technical field.
Previously described is each preferred embodiment of the present invention; preferred implementation in each preferred embodiment is if not obviously contradictory or take a certain preferred implementation as prerequisite; each preferred implementation arbitrarily stack combinations is used; design parameter among described embodiment and the embodiment only is the invention proof procedure for clear statement inventor; be not to limit scope of patent protection of the present invention; scope of patent protection of the present invention still is as the criterion with its claims; the equivalent structure that every utilization specification of the present invention and accompanying drawing content are done changes, and in like manner all should be included in protection scope of the present invention.
Claims (10)
1. the L-band upconverter of bandwidth 2GHz, comprise input interface and transmitting terminal, and be connected to emission of radio frequency signals path between input interface and the transmitting terminal, it is characterized in that, described emission of radio frequency signals path comprises intermediate-frequency bandwidth selection module, the first frequency mixer, filter, the second frequency mixer and the radio frequency amplifier of successively series connection; Also comprise the first local oscillator that is connected with the first frequency mixer, the second local oscillator that is connected with the second frequency mixer;
The output frequency of described the first local oscillator and the second local oscillator can be selected to regulate, and described intermediate-frequency bandwidth selects module to be used for input signal is carried out the subchannel gating.
2. the L-band upconverter of bandwidth 1.2GHz as claimed in claim 1 is characterized in that, also is connected with the radio-frequency channel between described radio frequency amplifier and the transmitting terminal and selects module, and described radio-frequency channel selects module that input signal is carried out segmentation output amplification.
3. the L-band upconverter of bandwidth 1.2GHz as claimed in claim 2 is characterized in that, described radio-frequency channel selects module to comprise the output channel that three passband start-stop frequencies are connected continuously, each output channel bandwidth 400 megahertz.
4. the L-band upconverter of bandwidth 1.2GHz as claimed in claim 2 is characterized in that, described radio-frequency channel is selected also to be connected with the program control attenuation module of the radio frequency amplifier output signal being carried out amplitude adjusted between module and the radio frequency amplifier output.
5. the L-band upconverter of bandwidth 1.2GHz as claimed in claim 1 is characterized in that, again output after the output that described intermediate-frequency bandwidth one of is selected in module, the first frequency mixer at least also is connected with amplifier output signal is amplified.
6. the L-band upconverter of bandwidth 1.2GHz as claimed in claim 1 is characterized in that, described the first local oscillator and/or the second local oscillator are fractional phase locked loop formula frequency synthesis oscillator.
7. the L-band upconverter of bandwidth 1.2GHz as claimed in claim 1 is characterized in that, the output frequency of described the first local oscillator is set and made the output signal frequency of the first frequency mixer greater than 2150MHz.
8. the L-band upconverter of bandwidth 1.2GHz as claimed in claim 1 is characterized in that, described the first local oscillator and the second local oscillator are positioned at central authorities, and all the other module distribution are in the first local oscillator and the second local oscillator periphery.
9. the L-band up-conversion implementation method of bandwidth 1.2GHz is characterized in that, comprises the steps:
Step 1. pair input signal carries out the subchannel gating.
Step 2. pair gating signal and First vibration frequency carry out the mixing first time and obtain the first mixed frequency signal;
Step 3. pair the first mixed frequency signal carries out filtering, and filtered signal and the second local frequency are carried out the mixing second time and obtained the second mixed frequency signal;
Carry out segmentation after step 4. the second mixed frequency signal amplifies and export the transmitting terminal emission to.
10. the L-band up-conversion implementation method of bandwidth 1.2GHz as claimed in claim 8 is characterized in that, the first mixed frequency signal frequency is greater than 2150 megahertzes in the described step 2.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105554422A (en) * | 2014-10-28 | 2016-05-04 | 江苏绿扬电子仪器集团有限公司 | System for terrestrial digital television frequency mixing and programmable attenuator |
| CN107135030A (en) * | 2017-06-28 | 2017-09-05 | 刘铭 | Ku band satellite uplink test instrument and its method of work |
| CN107526011A (en) * | 2017-08-28 | 2017-12-29 | 湖南时变通讯科技有限公司 | A kind of high-power micro discharge power loading system |
| CN108540097A (en) * | 2018-03-06 | 2018-09-14 | 北京理工大学 | A kind of broadband low spurious frequency conversion equipment |
| CN111638490A (en) * | 2020-06-22 | 2020-09-08 | 西安石油大学 | FMCW (frequency modulated continuous wave) transmitting circuit and method with bandwidth unchanged and center frequency capable of being continuously changed |
| CN111683027A (en) * | 2020-03-19 | 2020-09-18 | 广州润芯信息技术有限公司 | Satellite up-converter based on intermediate frequency analog predistortion |
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| US5390346A (en) * | 1994-01-21 | 1995-02-14 | General Instrument Corporation Of Delaware | Small frequency step up or down converters using large frequency step synthesizers |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105554422A (en) * | 2014-10-28 | 2016-05-04 | 江苏绿扬电子仪器集团有限公司 | System for terrestrial digital television frequency mixing and programmable attenuator |
| CN107135030A (en) * | 2017-06-28 | 2017-09-05 | 刘铭 | Ku band satellite uplink test instrument and its method of work |
| CN107526011A (en) * | 2017-08-28 | 2017-12-29 | 湖南时变通讯科技有限公司 | A kind of high-power micro discharge power loading system |
| CN108540097A (en) * | 2018-03-06 | 2018-09-14 | 北京理工大学 | A kind of broadband low spurious frequency conversion equipment |
| CN111683027A (en) * | 2020-03-19 | 2020-09-18 | 广州润芯信息技术有限公司 | Satellite up-converter based on intermediate frequency analog predistortion |
| CN111638490A (en) * | 2020-06-22 | 2020-09-08 | 西安石油大学 | FMCW (frequency modulated continuous wave) transmitting circuit and method with bandwidth unchanged and center frequency capable of being continuously changed |
| CN111638490B (en) * | 2020-06-22 | 2023-06-02 | 西安石油大学 | FMCW transmitting circuit and method with invariable bandwidth center frequency capable of continuously changing |
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Application publication date: 20131016 |