CN101359962A - Filter feedback multiplexed millimeter wave subcarrier optical controlled microwave beam forming network - Google Patents
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Abstract
The invention relates to a filter feedback reusable millimeter wave subcarrier light controlled microwave beam forming network, which belongs to the technical field of millimeter wave subcarrier optical controlled microwave beam forming, and is characterized in that a wavelength selecting reusable module transforms wide-spectrum light output by wide-spectrum light source to a comb-like spectrum; the comb-like spectrum is modulated by microwave signals which need to be transmitted, and the comb-like spectrum most energy of which is concentrated in the peak wavelength is formed after dispersive delay and amplification; then an adjustable filter in the wavelength selecting reusable module is utilized for inverse filtering to obtain each required signal; amplification efficiency of an erbium-doped optical fibre amplifier is greatly enhanced, and then the power level of useful spectra of the entire link is enhanced; and compared with that traditional wide-spectrum light passes through the light controlled microwave beam forming network, the invention enhances energy utilization.
Description
Technical field
It is a kind of signal processing system of millimeter wave subcarrier being done true time-delay that the light-operated microwave beam of filter feedback multiplexed millimeter wave subcarrier forms network, belong to optical communication and microwave in conjunction with the field, particularly relate to the light-operated phased array radar in broadband, optical control beam forms fields such as smart antenna.
Background technology
It is the important research direction that microwave photon is learned the field that light-operated microwave beam forms network (OBFN), it is to utilize lightwave technology that the wide-band microwave signal is carried out power division, phase control, and power is synthetic, thus realize control to the microwave signal spatial distribution.Wave beam the earliest forms and is mainly used in the middle of the phased array radar, mainly is to use phase shifter to realize beam position.But when needing to carry out a plurality of targets simultaneously function such as high-precision detection, tracking, location when radar, this just needs higher bandwidth and frequency, will produce the wave beam skewness based on the beam-forming network of phase shifter when the wideband operation, then can overcome wave beam deflection problem in the broadband system based on the beam-forming network of true time-delay (TTD).Early stage TTD module all constitutes with electric equipment such as coaxial cables, and when phased array antenna array element was a lot, wave beam formation partial volume was huge, and weight is big, and loss is big, and is subjected to electromagnetic interference easily.In the early 1980s, the wide bandwidth of optical treatment technology, low-loss, volume are little, in light weight etc., and advantage attracts people's Application Optics means to carry out the design that wave beam forms, and Here it is, and light-operated microwave beam forms network.Along with the increase of development of fiber technology and wide band multi-business wireless communication needs, light-operated microwave beam forms network and has become hot research in recent years, has presented tempting application prospect in fields such as military affairs, radio communication, economy, scientific researches.
At present, forming network based on the light-operated microwave beam of wide spectrum light source is the important implementation that current microwave beam forms network, and it has the delay precision height, good stability, anti-crosstalk and multipath effective, time-delay can be adjustable continuously etc. advantage.Problems such as it is lower that but it also faces the energy of light source application efficiency, and array scale autgmentability is not strong.
The present invention is in order to solve above-mentioned technical problem, proposed a kind ofly novel to form network based on the light-operated microwave beam of the multiplexing wide spectrum light source of filter, can effectively improve the energy utilization efficiency of system, easily expanding system array scale.
Summary of the invention
The objective of the invention is to: it is lower to solve the present light-operated microwave beam formation energy of light source application efficiency that network faced based on wide spectrum light source, problems such as array scale autgmentability is not strong, propose a kind ofly novel to form network based on the light-operated microwave beam of the multiplexing wide spectrum light source of filter, the energy utilization efficiency of effective raising system, expanding system array scale easily.
The invention is characterized in: contain: wide spectrum light source, wavelength are selected Multiplexing module, feedback multiplexed circulator, first erbium-doped fiber amplifier, M-Z modulator, second erbium-doped fiber amplifier, dispersion element and the 3rd erbium-doped fiber amplifier, wherein:
Wide spectrum light source, wavelength are 1534nm-1560nm, error ± 1dB, and gross power is 100mW;
Wavelength is selected Multiplexing module, selects the mixer of a multiplexing branch road and a N:1 to constitute in succession successively by beam splitter, the N bar wavelength of a 1:N, wherein:
The beam splitter of 1:N, input are the wide range light that described wide spectrum light source sends, and are output as the N spectrum light of having a lot of social connections;
N bar wavelength is selected multiplexing branch road, each bar wavelength selects branch road circulator of multiplexing route and a branch road tunable optic filter series connection to constitute, described branch road circulator receives a branch of wide range light by described 1:N beam splitter output, and described branch road tunable optic filter output is corresponding to the signal spectrum of this branch road;
The N:1 mixer is the coupler of a N:1, selects N signal spectrum of multiplexing branch road output to be combined into pectination spectrum described N bar wavelength, selects the output of Multiplexing module as described wavelength;
Feedback multiplexed circulator receives from the pectination spectrum of described N:1 mixer output and outputs to the amplification of first erbium-doped fiber amplifier again;
First erbium-doped fiber amplifier outputs to a M-Z modulator amplifying back pectination spectrum;
The M-Z modulator is modulated to the microwave signal of a needs transmission on the described pectination spectrum, and its microwave signal that need transmit is imported by a microwave source;
Second erbium-doped fiber amplifier receives the pectination spectrum after the described microwave signal modulation that needs transmission of being subjected to by the output of M-Z modulator, and is amplified, and outputs to described dispersion element again;
Dispersion element is a chirped fiber grating, the described pectination spectrum that receives is carried out chromatic dispersion time-delay after, output to described the 3rd erbium-doped fiber amplifier again and amplify;
The 3rd erbium-doped fiber amplifier, modulating through the described microwave signal of transmission that needs earlier, the pectination spectrum of chromatic dispersion time-delay amplifies again, after feeding back to described feedback multiplexed circulator again, again by this feedback multiplexed circulator reverse feedback to described N:1 mixer, the energy of the described feedback multiplexed circulator output that mixer will be received all concentrates on the spectrum at each peak wavelength place in the pectination spectrum, be divided into N bundle spectrum and oppositely be input to described N bar wavelength and select the feedback input end mouth of each tunable optic filter in the multiplexing branch road to carry out feedback filtering, filtered spectrum enters into described each wavelength, and to select output N road behind the reverse input end mouth of circulator of multiplexing branch road to have a signal of different delayed time used for the automated power equilibrium.
Invention effect: among the present invention, select Multiplexing module by the wavelength that filter and circulator are formed, can reduce unwanted light spectral component in the light path, the system amplified energy of making all concentrates on above the light signal of useful wavelength, can improve the utilization ratio of system capacity greatly, raising enters the optical signal level before the PD, thereby obtains better signal to noise ratio.Through experiment confirm, can improve PD front end luminous power and reach 8dB.Improve signal to noise ratio 16dB.In addition because the system capacity utilization ratio improves, and the system of same scale can support bigger array scale, make the system extension enhancing.
Description of drawings
The filter feedback multiplexed light-operated microwave beam of millimeter wave subcarrier of Fig. 1 forms the basic structure of network.
Embodiment
Basic principle of the present invention is: multiplexing by to the filter both forward and reverse directions, make the wide spectrum light source spectral pattern in the beam-forming network obtain shaping optimization, its amplification efficient in EDFA is greatly improved, and then improve in the whole link the effectively power level of spectrum, reach the raising energy utilization efficiency, new departure can effectively improve signal to noise ratio under identical system power, can support than the more massive array of common time delay network.The basic structure of this beam-forming network as shown in Figure 1.
The wide range light that sends by wide spectrum light source among Fig. 1, at first enter wavelength and select Multiplexing module, this module selects the mixer of a multiplexing branch road and a N:1 to constitute in succession successively by beam splitter, the N bar wavelength of a 1:N, wide range light is divided into N branch road by the 1:N beam splitter, each branch road all enters 1 port of this branch road circulator, enter filter by the 2 ports output from circulator behind the circulator, obtain the signal spectrum on this road, then the mixer of the signal spectrum on each road by N:1 is combined into a rood and behind pectination spectrum, selects Multiplexing module output by wavelength.2 ports of a circulator of output back pectination spectrum input.Enter EDFA after the 3 ports output of pectination spectrum through circulator and amplify, the spectrum after the amplification is through a modulated microwave signal that goes up of M-Z modulator.Pectination spectrum after this modulation is by behind the dispersion element, and different spectrum peaks has obtained different chromatic dispersion group delays.Again by after the EDFA amplification, enter 1 port of circulator by the pectination spectrum behind the dispersion element, select Multiplexing module by being input to wavelength again again after the output of 2 ports.Pectination spectrum is assigned to inverse filtering on each filter in wavelength selection Multiplexing module, enter into 2 ports of branch road circulator by the remaining spectrum in back, export power equalizer to by 3 ports, balanced each road luminous power makes the luminous power that arrives photodetector equate.Through the detection of photo-detector, the light microwave signal is reduced to microwave signal and the emission of process aerial array after the time-delay.
The wide spectrum light source that we adopt be 1530nm to 1560nm, gross power is 100mW, wavelength rises and falls and is not more than 1dB.Such wide range light enters wavelength and selects Multiplexing module, is divided into the N road by the 1:N coupler.Because the effect of circulator and tunable optic filter, a part of spectrum of wide range is filtered off and enters the N:1 coupler and close the road in each road.Closing spectrum behind the road and become the pectination of N the peak value that we need composes.N=4 during experiment, 4 peak wavelengths of the pectination spectrum that obtains are respectively 1553.1nm, 1555.2nm, 1557.3nm and 1559.4nm, the power fluctuation between each wavelength is not more than 1dB.
After selecting Multiplexing module by wavelength, pectination spectrum is amplified into an electrooptic modulator by EDFA, is required the microwave signal modulation of transmission.The pectination spectrum of having modulated microwave signal is admitted to dispersion element, and different spectral components obtains different chromatic dispersion group delays.Here the chromatic dispersion device can be high chromatic dispersion chirped fiber grating, multiple high dispersion waveguide such as high-dispersive photonic crystal fiber.The pectination spectrum that has obtained different chromatic dispersion time-delays enters EDFA once more and is exaggerated.Here EDFA is a power amplification EDFA, and it selects Multiplexing module that enough energy are provided for the pectination spectrum reenters wavelength.Because what EDFA amplified is pectination spectrum, its amplified energy all concentrates on each peak wavelength place in the pectination spectrum.Because what EDFA amplified in the light-operated microwave beam formation of the traditional wide spectrum light source network is even spectrum, what all energy were all average is assigned to above the whole wave band, the overwhelming majority can be gone filtering by back filtering, compare with traditional scheme, the energy of EDFA has all concentrated on the useful peak wavelength in new departure, the energy of overwhelming majority EDFA all has been used to amplify the using light signal in the filter band, their overwhelming majority in once more by filter all can be retained down, makes the system capacity utilization ratio improve greatly.N=4 during experiment, because the non-flatness of EDFA gain spectral pattern, the power that the 3rd EDFA amplifies back each spectral components of pectination spectrum is no longer equal, need level come balanced with the automated power equalizer after system.
Spectrum enters wavelength once more select Multiplexing module after, the coupling pectination spectrum by 1:N is divided into the N road, each road enters filter filtering once more.Obtain the needed spectral components in each road after the filtering.This component is fed to that equilibrium is a constant power value in the light power equalization module.Light signal after the equilibrium is admitted among the PD to be surveyed, and is reduced into the microwave signal after our time-delay, and experiment has obtained eye pattern clearly.
Our system is array extending quantity easily also, only need add that new wavelength selects Multiplexing module just can finish.The light-operated microwave beam of the filter feedback multiplexed millimeter wave subcarrier that has been extended to N=8 successful in the experiment forms network, and has obtained before the EDFA amplification and the spectrogram after the 3rd EDFA amplification.
Claims (1)
1. the light-operated microwave beam of filter feedback multiplexed millimeter wave subcarrier forms network, it is characterized in that, contain: wide spectrum light source, wavelength are selected Multiplexing module, feedback multiplexed circulator, first erbium-doped fiber amplifier, M-Z modulator, second erbium-doped fiber amplifier, dispersion element and the 3rd erbium-doped fiber amplifier, wherein:
Wide spectrum light source, wavelength are 1534nm-1560nm, error ± 1dB, and gross power is 100mW,
Wavelength is selected Multiplexing module, selects the mixer of a multiplexing branch road and a N:1 to constitute in succession successively by beam splitter, the N bar wavelength of a 1:N, wherein:
The beam splitter of 1:N, input are the wide range light that described wide spectrum light source sends, and are output as the N spectrum light of having a lot of social connections,
N bar wavelength is selected multiplexing branch road, each bar wavelength selects branch road circulator of multiplexing route and a branch road tunable optic filter series connection to constitute, described branch road circulator receives a branch of wide range light by described 1:N beam splitter output, described branch road tunable optic filter output is corresponding to the signal spectrum of this branch road
The N:1 mixer is the coupler of a N:1, selects N signal spectrum of multiplexing branch road output to be combined into pectination spectrum described N bar wavelength, as the output of described wavelength selection Multiplexing module,
Feedback multiplexed circulator receives from the pectination spectrum of described N:1 mixer output and outputs to the amplification of first erbium-doped fiber amplifier again,
First erbium-doped fiber amplifier outputs to a M-Z modulator amplifying back pectination spectrum,
The M-Z modulator is modulated to the microwave signal of a needs transmission on the described pectination spectrum, and its microwave signal that need transmit is imported by a microwave source,
Second erbium-doped fiber amplifier receives the pectination spectrum after the described microwave signal modulation that needs transmission of being subjected to by the output of M-Z modulator, and is amplified, and outputs to described dispersion element again,
Dispersion element is a chirped fiber grating, the described pectination spectrum that receives is carried out chromatic dispersion time-delay after, output to described the 3rd erbium-doped fiber amplifier again and amplify,
The 3rd erbium-doped fiber amplifier, modulating through the described microwave signal of transmission that needs earlier, the pectination spectrum of chromatic dispersion time-delay amplifies again, after feeding back to described feedback multiplexed circulator again, again by this feedback multiplexed circulator reverse feedback to described N:1 mixer, the energy of the described feedback multiplexed circulator output that mixer will be received all concentrates on the spectrum at each peak wavelength place in the pectination spectrum, be divided into N bundle spectrum and oppositely be input to described N bar wavelength and select the feedback input end mouth of each tunable optic filter in the multiplexing branch road to carry out feedback filtering, filtered spectrum enters into described each wavelength, and to select output N road behind the reverse input end mouth of circulator of multiplexing branch road to have a signal of different delayed time used for the automated power equilibrium.
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| CN102147634B (en) * | 2010-11-24 | 2014-05-07 | 中国科学院半导体研究所 | Optical vector-matrix multiplier based on single-waveguide coupling micro-ring resonant cavity |
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| CN103532604A (en) * | 2013-09-30 | 2014-01-22 | 上海交通大学 | Programmable beam forming network on basis of optical wavelength division multiplexing technology |
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| CN108710174B (en) * | 2018-05-28 | 2020-03-27 | 天津大学 | UDWDM-PON transmitter based on wavelength automatic locking and tracking technology |
| CN111142089A (en) * | 2020-01-10 | 2020-05-12 | 清华大学 | OBFN and PADC function integrated broadband radar signal receiving device and method |
| CN111142089B (en) * | 2020-01-10 | 2021-09-21 | 清华大学 | OBFN and PADC function integrated broadband radar signal receiving device and method |
| CN111740786A (en) * | 2020-06-10 | 2020-10-02 | 电子科技大学 | Integrated optical waveguide beam forming device |
| CN111694162A (en) * | 2020-06-22 | 2020-09-22 | 中国科学院西安光学精密机械研究所 | Spectrum synthesis method and device |
| CN113872697A (en) * | 2020-06-30 | 2021-12-31 | 华为技术有限公司 | Optical transmitter and optical modulation method |
| CN113872697B (en) * | 2020-06-30 | 2023-09-12 | 华为技术有限公司 | Optical transmitter and optical modulation method |
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| CN115967445A (en) * | 2022-06-29 | 2023-04-14 | 中兴通讯股份有限公司 | Method, equipment and system for generating optical network topology |
| CN115967445B (en) * | 2022-06-29 | 2024-03-19 | 中兴通讯股份有限公司 | Method, equipment and system for generating optical network topology |
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