CN103684610A - Remote high-frequency microwave oscillating source in optical millimeter wave system - Google Patents
Remote high-frequency microwave oscillating source in optical millimeter wave system Download PDFInfo
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- CN103684610A CN103684610A CN201310447350.8A CN201310447350A CN103684610A CN 103684610 A CN103684610 A CN 103684610A CN 201310447350 A CN201310447350 A CN 201310447350A CN 103684610 A CN103684610 A CN 103684610A
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Abstract
The invention provides a remote high-frequency microwave oscillating source in an optical millimeter wave system. 90% of laser generated by a DFB (Distributed Feed Back) laser is input into a 40G modulator via a polarization controller, 10Gbit/s NRZ (Non Return to Zero) data is amplified by an SHF803P and then input into the 40G modulator, and data intensity modulation is implemented on the laser to generate high-speed broadband modulated light; the light is amplified by an erbium doped fiber amplifier, then input into an XTM50, and filtered to obtain a multiplex clock spectrum, and the spectrum is combined with 10% DFB laser to obtain a spectrum of the high-frequency microwave oscillating source; and the spectrum of the high-frequency microwave oscillating source is amplified via a KPS erbium doped fiber amplifier, input to a near dispersion flattened fiber set, and transmitted to a remote base station to form the high-frequency microwave oscillating source, and electrical signals after beat frequency can replace an electric local oscillator source in a millimeter wave uplink system. Backward Raman amplification is employed; and an AQ6319 and an E4440A respectively measure the spectral and electrographic characteristics of signals. The method for generating the remote high-frequency microwave oscillating source can be used as significant reference in researching the optical millimeter wave system in a high bit rate, and can be widely applied to the fields including microwave photonics and fiber communication.
Description
Affiliated technical field
The present invention relates to a kind of remote high-frequency microwave generating source in optical millimeter wave system, can be applicable to the fields such as Microwave photonics, optical fiber communication, wireless optical fiber access.
Background technology
In recent years, the miscellaneous services such as large data, mobile traffic, broadband streaming media constantly increase severely, and High rate and large capacity wireless communication needs increases day by day.In order to realize wireless broadband communication, must improve its operating frequency.Yet, most of wireless traffics both domestic and external all concentrate on below 3GHz at present, and existing low-frequency range frequency resource is nearly all occupied, for the less commercial system that is applied to frequency resource more than 3GHz (as 40GHz, 60GHz), be mostly applied to experimental study.If can make full use of this frequency range window business telecommunication, not only can make full use of existing frequency spectrum resource, but also can realize the wireless access of ultra broadband.But, raising along with wireless broadband communication operating frequency, the complicated geographical environment such as high-rise, high mountain in electromagnetic reflection and shielding action and atmosphere because absorb and loss that reflection causes etc. increases gradually, and make the networking of wireless broadband network become complicated.For addressing the above problem, the optical millimeter wave communication technology Radio-over-Fiber (RoF) that Fibre Optical Communication Technology and high frequency wireless access are merged should need and give birth to.At present, optical millimeter wave generation, transmission and reception technique have become the study hotspot of realizing ultra broadband access as a kind of emerging communication technology growing up.
The generation of optical millimeter wave, transmission and reception technique are the important technologies of realizing high performance communication.Yet, in the up subsystem of optical millimeter wave, conventionally all have to introduce an expensive electric high-frequency local oscillation source (as 40GHz, 60GHz), if can adopt an effective measure, substituting electric high-frequency local oscillation source will be the progress that this system is very large.In view of optical millimeter wave system requires harshness to device performance parameter, Fiber-optic parameter etc., optical millimeter wave produces in experimental technique at present, mostly adopts data compared with low rate situation, as 5Gbit/s and following.Yet China is vast in territory, populous, information communication demand rapid growth, it is day by day urgent that the communication requirement of high rate optical millimeter wave becomes.As can be seen here, solve innovatively the substitution problem in electric high-frequency local oscillation source and realize the key point that two-forty is optical millimeter wave research.
Content of the patent
In the day by day urgent situation of optical millimeter wave two-forty demand, for the problem in above-mentioned optical millimeter wave research, in 40GHz, 10Gbit/s high rate optical millimeter-wave systems, the present invention proposes a kind of remote high-frequency microwave generating source, to substitute the electric high-frequency local oscillation source in high rate optical millimeter wave up-link.
The technical solution adopted for the present invention to solve the technical problems is:
For 40GHz, 10Gbit/s high rate optical millimeter-wave systems, the present invention proposes a kind of remote high-frequency microwave generating source method and apparatus, intend the technical scheme adopting: the laser that narrow linewidth Distributed Feedback Laser produces is after the shunt of 10:90 splitter, wherein 90% laser enters 40G high-speed wideband modulator through optical polarization controller, the 10Gbit/s two-forty NRZ pseudo-random pulse data sequence signal of Agilent 43Gbit/s Error Detector 81250 outputs enters 40G high-speed wideband modulator after amplifying via broadband electric amplifier SHF803P simultaneously, narrow-linewidth laser is produced two-forty wide-band modulation light by intensity data modulation, here the two-forty wide-band modulation light producing can be along separate routes produce optical millimeter wave and microwave generating source as the part of descending optical millimeter wave signal simultaneously, but only discuss the microwave generating source situation that produces here, two-forty wide-band modulation light is amplified into optical filter XTM50 through 17dBm erbium-doped fiber amplifier, after filtering, obtain many times of clock spectrum of 40GHz, 10% the laser spectroscopy that this clock spectrum and splitter separate obtains high-frequency microwave oscillation source signal spectrum after 1:99 mixer closes road, and wherein clock spectrum enters mixer by 99% port, the spectrum of high-frequency microwave oscillation source is amplified into 70GHz photodetector beat frequency through KPS erbium-doped fiber amplifier and obtains electric high-frequency microwave oscillation source signal, this microwave oscillation source signal is amplified into frequency mixer 11970U through broadband electric amplifier SHF806E and carries out mixing, finally by electric spectrometer E4440A Measurement and analysis electricity spectrality energy, wherein, KPS erbium-doped fiber amplifier and light path link thereof can be used spectroanalysis instrument AQ6319 to measure the spectrum property of signal.
High-frequency microwave oscillation source signal spectrum after KPS erbium-doped fiber amplifier amplifies enters nearly Dispersion Flattened Fiber group transmission 84.7km and arrive remote base stations formation remote high-frequency microwave generating source, the electric high-frequency local oscillation source in the alternative high rate optical millimeter wave of the signal of telecommunication up-link forming after remote base stations beat frequency; In order to guarantee signal transmission quality, the pump light that raman pump source produces enters optical fiber group through wavelength division multiplexer high-frequency microwave oscillation source signal is carried out to backward Raman amplification; Afterwards, remote high-frequency microwave oscillation source signal enters electric spectrality energy measurement links.
The invention has the beneficial effects as follows:
In 40GHz, 10Gbit/s high rate optical millimeter-wave systems, the present invention proposes a kind of remote high-frequency microwave generating source; Adopt same DFB LASER Light Source to produce high rate optical millimeter wave and remote high-frequency microwave generating source, can effectively suppress phase noise; The DFB laser adopting has narrow linewidth, high side mode suppression ratio characteristic, effectively inhibition strength noise; Adopt the 10Gbit/s high data rate of Error Detector 81250 outputs to go intensity modulated DFB narrow-linewidth laser can improve data rate by a wideband modulator.With adopt radio frequency and baseband signal respectively phase modulation and intensity two kinds produce optical millimeter wave methods and compare, the present invention can produce high rate optical millimeter wave and remote high-frequency microwave generating source simultaneously, and optical millimeter wave system medium-long range high-frequency microwave oscillation source produces scheme novelty, simple possible, can effectively suppress noise.This patent method and apparatus can be used as the important references of exploratory development high bit rate optical millimeter wave system, can be applicable to the fields such as Microwave photonics, optical fiber communication.
Accompanying drawing explanation
Fig. 1 is that a kind of remote high-frequency microwave generating source in 40GHz, 10Gbit/s high rate optical millimeter-wave systems produces and survey map.In Fig. 1, the 1st, narrow linewidth Distributed Feedback Laser, the 2nd, 10:90 splitter, the 3rd, optical polarization controller, the 4th, 40G high-speed wideband modulator, the 5th, Agilent 43Gbit/s Error Detector 81250,6th, broadband electric amplifier SHF803P, the 7th, 17dBm erbium-doped fiber amplifier, the 8th, optical filter XTM50, the 9th, 1:99 mixer, the 10th, KPS erbium-doped fiber amplifier, the 11st, 70GHz photodetector, the 12nd, broadband electric amplifier SHF806E, the 13rd, frequency mixer 11970U, the 14th, electric spectrometer E4440A, the 15th, spectroanalysis instrument AQ6319; Electricity spectrometer E4440A measuring-signal electricity spectrality energy; Spectroanalysis instrument AQ6319 measures the spectrum property of signal, can adopt optical patchcord directly to access.
Fig. 2 is high-frequency microwave oscillation source remote transmission and survey map thereof, and (10), (11) in Fig. 2, (12), (13), (14), (15) are consistent with each device in Fig. 1, are connected with Fig. 1.In Fig. 2,16 is nearly Dispersion Flattened Fiber group (first G655 optical fiber, then connect Dispersion Flattened Fiber), the 17th, and raman pump source, the 18th, wavelength division multiplexer.
Fig. 3 is the high-frequency microwave oscillation source spectrum after KPS erbium-doped fiber amplifier amplifies.
Fig. 4 is that the high-frequency microwave oscillation source spectrum after KPS erbium-doped fiber amplifier amplifies transmits the spectrum after amplifying with Raman through the nearly Dispersion Flattened Fiber group of 84.7km.
Fig. 5 is the high-frequency microwave oscillation source electricity spectrum corresponding with Fig. 3 spectrum.
Fig. 6 is the high-frequency microwave oscillation source electricity spectrum corresponding with Fig. 4 spectrum.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further described with enforcement.
Shown in Fig. 1, the laser that narrow linewidth Distributed Feedback Laser (1) produces is after 10:90 splitter (2) shunt, wherein 90% laser enters 40G high-speed wideband modulator (4) through optical polarization controller (3), the 10Gbit/s two-forty NRZ pseudo-random pulse data sequence signal of Agilent 43Gbit/s Error Detector 81250 (5) outputs enters 40G high-speed wideband modulator (4) after amplifying via broadband electric amplifier SHF803P (6) simultaneously, narrow-linewidth laser is produced two-forty wide-band modulation light by intensity data modulation, here the two-forty wide-band modulation light producing can be along separate routes produce optical millimeter wave and microwave generating source as the part of descending optical millimeter wave signal simultaneously, but only discuss the microwave generating source situation that produces here, two-forty wide-band modulation light is amplified into optical filter XTM50 (8) through 17dBm erbium-doped fiber amplifier (7), after filtering, obtain many times of clock spectrum of 40GHz, 10% the laser spectroscopy that this clock spectrum and splitter separate obtains high-frequency microwave oscillation source signal spectrum after 1:99 mixer (9) closes road, and wherein clock spectrum enters mixer by 99% port, the spectrum of high-frequency microwave oscillation source is amplified into 70GHz photodetector (11) beat frequency through KPS erbium-doped fiber amplifier (10) and obtains electric high-frequency microwave oscillation source signal, this microwave oscillation source signal is amplified into frequency mixer 11970U (13) through broadband electric amplifier SHF806E (12) and carries out mixing, after by the electric spectrality energy before electric spectrometer E4440A (14) Measurement and analysis high-frequency microwave oscillation source signal spectral transmissions, wherein, KPS erbium-doped fiber amplifier (10) and light path link thereof can directly adopt optical patchcord connection spectroanalysis instrument AQ6319 (15) to measure the spectrum property of signal.
Shown in Fig. 2, (10), (11) in figure, (12), (13), (14) are consistent with each device in Fig. 1, are connected with Fig. 1.High-frequency microwave oscillation source signal spectrum after KPS erbium-doped fiber amplifier (10) amplifies enters nearly Dispersion Flattened Fiber group (16) transmission 84.7km and arrive remote base stations formation remote high-frequency microwave generating source, the electric high-frequency local oscillation source in the alternative high rate optical millimeter wave of the signal of telecommunication up-link forming after remote base stations beat frequency; In order to guarantee signal transmission quality, the pump light that raman pump source (17) produces enters optical fiber group through wavelength division multiplexer (18) high-frequency microwave oscillation source signal is carried out to backward Raman amplification; Afterwards, remote high-frequency microwave oscillation source signal enters electric spectrality energy measurement links (11-14).
Fig. 3 is the high-frequency microwave oscillation source spectrum after KPS erbium-doped fiber amplifier amplifies.The light wave of these two wavelength is produced by same laser, can effectively suppress phase noise; The clock spectrum centre wavelength 1949.608nm visible in figure, filtering obtains, clock is composed up to 29dB, and spectral line is more smooth, about clock spectrum center, has good symmetry.Spectrum after the laser shunt that narrow linewidth Distributed Feedback Laser produces still keeps primary characteristic, than the slightly high 12.7dB of clock spectrum.
Fig. 4 is that the high-frequency microwave oscillation source spectrum after KPS erbium-doped fiber amplifier amplifies amplifies the spectrum after 25dBm through the nearly Dispersion Flattened Fiber group transmission of 84.7km with Raman.Although after high-frequency microwave oscillation source spectral transmissions, luminous power reduces to some extent, still has good spectral characteristic.
Fig. 5 is the high-frequency microwave oscillation source electricity spectrum corresponding with Fig. 3 spectrum.Visible in figure, oscillation source electricity spectrum is stable, clear, can reach 28.52dB; Electricity spectrum single-frequency performance is good, its-ratio of three dB bandwidth and electric spectral frequency is 2.353 * 10
-5.
Fig. 6 is the high-frequency microwave oscillation source electricity spectrum corresponding with Fig. 4 spectrum.After transmission, oscillation source electricity spectrum still has good single-frequency, and stable, clear, amplitude can reach 18.3dB, and suitably amplification can reach higher amplitude.
The associated arguments being measured from Fig. 3-Fig. 6, this patent method can provide a kind of remote high-frequency microwave generating source in 40GHz, 10Gbit/s high rate optical millimeter-wave systems, to substitute the electric high-frequency local oscillation source in high rate optical millimeter wave up-link.
Claims (1)
1.40GHz, a kind of remote high-frequency microwave oscillation source generating method and device in 10Gbit/s high rate optical millimeter-wave systems, it is characterized in that: the laser that narrow linewidth Distributed Feedback Laser (1) produces is after 10:90 splitter (2) shunt, wherein 90% laser enters 40G high-speed wideband modulator (4) through optical polarization controller (3), the 10Gbit/s two-forty NRZ pseudo-random pulse data sequence signal of Agilent 43Gbit/s Error Detector 81250 (5) outputs enters 40G high-speed wideband modulator (4) after amplifying via broadband electric amplifier SHF803P (6) simultaneously, narrow-linewidth laser is produced two-forty wide-band modulation light by Data Modulation, here the two-forty wide-band modulation light producing can be along separate routes as the part of descending optical millimeter wave signal, but only discuss the microwave generating source situation that produces here, two-forty wide-band modulation light is amplified into optical filter XTM50 (8) through 17dBm erbium-doped fiber amplifier (7), after filtering, obtain many times of clock spectrum, 10% the laser spectroscopy that this clock spectrum and splitter separate obtains high-frequency microwave oscillation source signal spectrum after 1:99 mixer (9) closes road, and wherein clock spectrum enters mixer by 99% port, the spectrum of high-frequency microwave oscillation source is amplified into 70GHz photodetector (11) beat frequency through KPS erbium-doped fiber amplifier (10) and obtains electric high-frequency microwave oscillation source signal, this microwave oscillation source signal is amplified into frequency mixer 11970U (13) through broadband electric amplifier SHF806E (12) and carries out mixing, afterwards by the electric spectrality energy before electric spectrometer E4440A (14) Measurement and analysis high-frequency microwave oscillation source signal spectral transmissions, wherein, KPS erbium-doped fiber amplifier (10) and light path link thereof can be used spectroanalysis instrument AQ6319 (15) to measure the spectrum property of signal, during transmission, high-frequency microwave oscillation source signal spectrum after KPS erbium-doped fiber amplifier (10) amplifies enters nearly Dispersion Flattened Fiber group (16) transmission 84.7km and arrive remote base stations formation remote high-frequency microwave generating source, the electric high-frequency local oscillation source in the alternative high rate optical millimeter wave of the signal of telecommunication up-link forming after remote base stations beat frequency, in order to guarantee signal transmission quality, the pump light that raman pump source (17) produces enters optical fiber group through wavelength division multiplexer (18) high-frequency microwave oscillation source signal is carried out to backward Raman amplification, afterwards, remote high-frequency microwave oscillation source signal enters electric spectrality energy measurement links (11-14).
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105099566A (en) * | 2015-06-30 | 2015-11-25 | 西安电子科技大学 | Device for generating millimeter wave signals by using double independent tunable fiber lasers |
| CN112217566A (en) * | 2020-10-22 | 2021-01-12 | 聊城大学 | Remote high-frequency microwave oscillation source system based on single-stage nonlinear spectrum expansion |
| CN112272059A (en) * | 2020-10-29 | 2021-01-26 | 聊城大学 | Remote high-frequency microwave oscillation source system based on two-stage nonlinear spectrum expansion |
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| JP3570927B2 (en) * | 1999-07-21 | 2004-09-29 | 日本電信電話株式会社 | Optical fiber communication system using Raman amplification. |
| CN101951294A (en) * | 2010-08-05 | 2011-01-19 | 暨南大学 | Microwave/millimeter wave signal generating device with continuously tunable broadband |
| CN102629887A (en) * | 2012-05-09 | 2012-08-08 | 电子科技大学 | Full-duplex radio-over-fiber (RoF) access device |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3570927B2 (en) * | 1999-07-21 | 2004-09-29 | 日本電信電話株式会社 | Optical fiber communication system using Raman amplification. |
| CN101951294A (en) * | 2010-08-05 | 2011-01-19 | 暨南大学 | Microwave/millimeter wave signal generating device with continuously tunable broadband |
| CN102629887A (en) * | 2012-05-09 | 2012-08-08 | 电子科技大学 | Full-duplex radio-over-fiber (RoF) access device |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105099566A (en) * | 2015-06-30 | 2015-11-25 | 西安电子科技大学 | Device for generating millimeter wave signals by using double independent tunable fiber lasers |
| CN112217566A (en) * | 2020-10-22 | 2021-01-12 | 聊城大学 | Remote high-frequency microwave oscillation source system based on single-stage nonlinear spectrum expansion |
| CN112217566B (en) * | 2020-10-22 | 2023-09-08 | 聊城大学 | Remote high-frequency microwave oscillation source system based on single-stage nonlinear spectrum expansion |
| CN112272059A (en) * | 2020-10-29 | 2021-01-26 | 聊城大学 | Remote high-frequency microwave oscillation source system based on two-stage nonlinear spectrum expansion |
| CN112272059B (en) * | 2020-10-29 | 2023-09-29 | 聊城大学 | Remote high-frequency microwave oscillation source system based on two-stage nonlinear spread spectrum |
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Effective date of registration: 20170627 Address after: 252059 No. 34, Wenhua Road, Shandong, Liaocheng Patentee after: Liaocheng University high and New Technology Industry Corp. Address before: 252059 No. 34, Wenhua Road, Shandong, Liaocheng Patentee before: Liaocheng University |
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