CN102721955B - Balanced type photoelectric detector in 2mu m coherent laser wind-finding radar system - Google Patents
Balanced type photoelectric detector in 2mu m coherent laser wind-finding radar system Download PDFInfo
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- CN102721955B CN102721955B CN201210202640.1A CN201210202640A CN102721955B CN 102721955 B CN102721955 B CN 102721955B CN 201210202640 A CN201210202640 A CN 201210202640A CN 102721955 B CN102721955 B CN 102721955B
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Abstract
The invention discloses a balanced type photoelectric detector in a 2mu m coherent laser wind-finding radar system, which aims at solving the problems that in the 2mu m coherent laser wind-finding radar system, analog devices of the balanced type heterodyne photoelectric detector are multiple, so that no only is the cost high, but also heat noise is caused. Two PIN photoelectric diodes with almost completely same parameters are manufactured on one detection unit simultaneously. Incident signal light and local light are divided into two beams respectively through a beam splitter, are respectively guided into two reverse PIN tubes with matched parameters so as to carry out optical frequency mixing on light sensitive surfaces of two PIN photoelectric detectors, then generating heterodyne signals respectively, and outputting the balanced heterodyne intermediate-frequency signal by a two-stage amplifier after passing through a differentiator, wherein a capacitor C1, a capacitor C2 and a capacitor C3 play a role in filtering. The balanced type photoelectric detector disclosed by the invention is used for converting optical signals into electric signals.
Description
Technical field
The present invention relates to a kind of photodetector, particularly balanced type photodetector in a kind of 2 mu m coherent laser windfinding radar systems.
Background technology
Adopt at present balanced type heterodyne detection technology, overcome the impact of local oscillator light shot noise on heterodyne detection signal to noise ratio (S/N ratio) in 2-m coherent laser windfinding radar system, by the output that there is the photodiode of same alike result by two, carry out difference and just can eliminate local oscillator optical noise, improve the signal to noise ratio (S/N ratio) of heterodyne signal, its principle of work as shown in Figure 1, balanced type heterodyne reception unit is comprised of two detectors in parallel, and every detector has independently photodiode (PIN), low-noise preamplifier, main amplifier and bandpass filter.Flashlight and local oscillator light are divided into upper and lower two-way through beam splitter respectively.Flashlight and local oscillator Guang Xia road project on photodiode below in the lump, and flashlight is set out on a journey and the local oscillator light of 180 ° of phase shifts projects on photodiode above in the lump.The output signal of two-way detector (single spin-echo) together enters compositor and exports intermediate-freuqncy signal again.
According to photoelectric effect, the output terminal on two detectors obtains photocurrent (loading generation photovoltage), wherein η
1, η
2the quantum efficiency that represents respectively two detectors, ε and (1-ε) are the splitting ratio of single-mode polarization maintaining fiber beam splitter, S
2and L
2the distribution of light intensity that represents flashlight and reference light, has following formula:
Carrier To Noise Power Density N in two detectors
1and N
2, can be expressed as respectively:
If suppose that the filter function in two-way is A
1, so just on photocurrent and not impact of noise.In order to shift the signal to noise ratio (S/N ratio) density of this system onto, the gain factor of first hypothesis gain 2 is A
1, by changing gain A
1gain factor, analyze signal to noise ratio (S/N ratio) power density.At this moment the difference electric current of intermediate frequency of system and differential noise power are respectively:
Thereby can obtain signal to noise ratio (S/N ratio), be:
At this moment, if the signal to noise ratio (S/N ratio) that independent derivation detector 1 or detector 2 work independently only need allow gain A
1for infinitely great or be zero, obtain:
Because single-element detector is the special circumstances of balanced type detector, but be not optimum, therefore, clearly the detection performance of both-end detector is minimum identical with single-element detector.
2 μ m balanced type heterodyne photodetectors are used for the beat frequency of settling signal light and local oscillator light, and the intermediate-freuqncy signal after beat frequency are amplified to meet the requirement of digital information processing system.
At present, the analog device of balanced type heterodyne photodetector is more, and not only cost is high, and analog device also brings thermonoise.
Summary of the invention
The object of the invention is in order to solve in 2 mu m coherent laser windfinding radar systems, the analog device of balanced type heterodyne photodetector is more, not only cost is high, analog device also brings thermonoise problem, the invention provides balanced type photodetector in a kind of 2 mu m coherent laser windfinding radar systems.
Balanced type photodetector in 2 mu m coherent laser windfinding radar systems, it comprises the first PIN photodiode, the second PIN photodiode, resistance R 1, resistance R 2, resistance R 3, capacitor C 1, capacitor C 2, capacitor C 3, one-level amplifier, two-stage amplifier, a FC/APC port and the 2nd FC/APC port, the flashlight output port of the one FC/APC port is connected with the light signal receiving end of the first PIN photodiode, one end of the negative electrode connecting resistance R1 of the first PIN photodiode, the positive pole of another termination power supply of described resistance R 1, the local oscillator optical output port of the 2nd FC/APC port is connected with the light signal receiving end of the second PIN photodiode, one end of the anode connecting resistance R2 of the second PIN photodiode, the negative pole of another termination power supply of described resistance R 2, the anode of the first PIN photodiode, the negative electrode of the second PIN photodiode, one end of resistance R 3 is connected with one end of capacitor C 1 simultaneously, another termination power ground of described resistance R3, the other end of described capacitor C 1 is connected with the amplifying signal input end of one-level amplifier, the amplifying signal output terminal of one-level amplifier is connected with one end of capacitor C 2, the other end of capacitor C 2 is connected with the amplifying signal input end of two-stage amplifier, the amplifying signal output terminal of two-stage amplifier is connected with one end of capacitor C 3, the other end of capacitor C 3 is the intermediate-freuqncy signal output terminal of balanced type photodetector in 2 mu m coherent laser windfinding radar systems.
Advantage of the present invention is: according to balance heterodyne detection principle, 2 μ m balanced type photodetectors of band optical fiber input FC/APC port of the present invention can be collected atmospheric backscatter flashlight and the local oscillator light by 50/50 single-mode polarization maintaining fiber beam splitter, can eliminate the amplitude noise that local oscillator light produces simultaneously, for existing balanced type heterodyne photodetector, some analog devices have been reduced, reduce cost, also reduced the thermonoise that analog device brings.
Accompanying drawing explanation
Fig. 1 is the structural representation of existing balanced type heterodyne detector.
Fig. 2 is the structural representation of balanced type photodetector in 2 mu m coherent laser windfinding radar systems of the present invention.
Fig. 3 is the experimental circuit schematic diagram of the effect of balanced type photodetector in checking 2 mu m coherent laser windfinding radar systems of the present invention.
Fig. 4 be in 2 mu m coherent laser windfinding radar systems of the present invention balanced type photodetector when operating voltage is 5.0V, the time-domain signal schematic diagram of the first PIN photodiode.Horizontal ordinate represents the time, and ordinate represents the output voltage of the first PIN photodiode.
Fig. 5 be in 2 mu m coherent laser windfinding radar systems of the present invention balanced type photodetector when operating voltage is 5.0V, the time-domain signal schematic diagram of the second PIN photodiode.Horizontal ordinate represents the time, and ordinate represents the output voltage of the second PIN photodiode.
Fig. 6 be the present invention when operating voltage is 5.0V, the time-domain signal schematic diagram of the intermediate-freuqncy signal of balanced type photodetector output in 2 mu m coherent laser windfinding radar systems of the present invention.Horizontal ordinate represents the time, and ordinate represents output voltage of the present invention.
Fig. 7 be the present invention when operating voltage is 5.0V, the frequency-region signal schematic diagram of the intermediate-freuqncy signal of balanced type photodetector output in 2 mu m coherent laser windfinding radar systems of the present invention.Horizontal ordinate represents frequency, and ordinate represents output amplitude of the present invention.
Embodiment
Embodiment one: present embodiment is described below in conjunction with Fig. 2 to Fig. 7, balanced type photodetector in 2 mu m coherent laser windfinding radar systems, it comprises the first PIN photodiode 1, the second PIN photodiode 2, resistance R 1, resistance R 2, resistance R 3, capacitor C 1, capacitor C 2, capacitor C 3, one-level amplifier 3, two-stage amplifier 4, a FC/APC port 5 and the 2nd FC/APC port 6, the flashlight output port of the one FC/APC port 5 is connected with the light signal receiving end of the first PIN photodiode 1, one end of the negative electrode connecting resistance R1 of the first PIN photodiode 1, the positive pole of another termination power supply of described resistance R 1, the local oscillator optical output port of the 2nd FC/APC port 6 is connected with the light signal receiving end of the second PIN photodiode 2, one end of the anode connecting resistance R2 of the second PIN photodiode 2, the negative pole of another termination power supply of described resistance R 2, the anode of the first PIN photodiode 1, the negative electrode of the second PIN photodiode 2, one end of resistance R 3 is connected with one end of capacitor C 1 simultaneously, another termination power ground of described resistance R3, the other end of described capacitor C 1 is connected with the amplifying signal input end of one-level amplifier 3, the amplifying signal output terminal of one-level amplifier 3 is connected with one end of capacitor C 2, the other end of capacitor C 2 is connected with the amplifying signal input end of two-stage amplifier 4, the amplifying signal output terminal of two-stage amplifier 4 is connected with one end of capacitor C 3, the other end of capacitor C 3 is the intermediate-freuqncy signal output terminal of balanced type photodetector in 2 mu m coherent laser windfinding radar systems.
On a probe unit, make two PIN photodiode that parameter is almost completely identical simultaneously.Incoming signal light and local oscillator light are divided into two bundles through beam splitter respectively, import to respectively on two reverse PIN pipes of parameter matching and carry out optical mixing on two PIN photodetector photosurfaces, produce separately heterodyne signal, after difference engine, by two-stage amplifier, export balance heterodyne intermediate-freuqncy signal.Capacitor C 1, capacitor C 2 and capacitor C 3 strobe, and the capacitance of capacitor C 1, capacitor C 2 and capacitor C 3 is 5pF simultaneously, and the resistance of resistance R 1 and resistance R 2 is 50 Ω, and the resistance of R3 is 1 * 10
4Ω, the first PIN photodiode 1 and the 2nd PI photodiode 2 models are GH150-2; One-level amplifier 3 models are that LT1012 and two-stage amplifier 4 models are MAX494.
The first PIN photodiode 1 and the second PIN photodiode 2 are in the same way time, and a road adds 180 ° of phase shifters therein.
In 2 mu m coherent laser windfinding radar systems of the present invention, the technical indicator of balanced type photodetector is as shown in table 1.
Table 1 technical indicator of the present invention
| Characterisitic parameter | Symbol | Representative value | Unit | |
| Spectral response range | λ | 2050 | nm | |
| Sensitivity | ρ | 1 | A/W | |
| Noise | NEP | 20 | pA/(Hz) 1/2 | |
| Quantum efficiency | η | 0.7 | - | |
| | G | 20 | dB | |
| -three | BW | 150 | MHz | |
| | R | B | 50 | Ω |
| Operating voltage | V B | 5 | V | |
| Input port | - | FC/APC | - | |
| Damage threshold | - | 3 | dBm |
Under the experimental circuit schematic diagram shown in Fig. 3,
The maximum polarization light output power of the continuous wave laser of 2 μ m single-mode polarization maintaining fibers is 100mW, the FC/APC output terminal of the continuous wave laser of 2 μ m single-mode polarization maintaining fibers is connected with the FC/APC input end of the 100MHz acousto-optic frequency shifters of 2 mu m all-fibers, after online adjustable attenuator, the bundling device by 2 μ m single-mode polarization maintaining fibers closes bundle to its 0 grade of light with 1 grade of light, the splitting ratio of bundling device is 50/50, the luminous power of then closing after bundle is equally divided into two parts, be injected into respectively on two photosurfaces of balanced type photodetector in 2 mu m coherent laser windfinding radar systems of the present invention, in 2 mu m coherent laser windfinding radar systems of the present invention, the balance external difference signal of balanced type photodetector output is received on oscillograph through intermediate frequency amplifier, on oscillograph, just can observe the heterodyne signal of 100MHz.Because the characteristic of two photodiodes of balanced type photodetector is identical, therefore in order to observe the impact of best local oscillator luminous power on heterodyne signal signal to noise ratio (S/N ratio) on oscillograph, detector of the present invention any one input end signal wherein can be removed, so just obtain the heterodyne signal of single-element detector.
On the basis of the experimental circuit principle shown in Fig. 3, verify the feasibility of balanced type photodetector in 2 mu m coherent laser windfinding radar systems of the present invention.Still continuous wave laser output power is fixed on to 1.4mW, utilizing the local oscillator luminous power of two FC/APC input ends of balanced type photodetector in luminous power instrumentation 2 mu m coherent laser windfinding radar systems of the present invention by an additional online adjustable attenuator in light path, to make the injected optical power of two FC/APC input ends identical respectively, is all 0.40mW.Then remove local oscillator light, the size of testing the first PIN photodiode input end signal luminous power is 0.90mW, and the second PIN photodiode signal light power is 0.89mW.Still by oscillograph, observe respectively signal and the balanced type differential output signal of the photodiode output of each unit.
As can be seen from Figure 4 and Figure 5, the signal phase that two unit light electric diodes are exported separately differs 180 °, meet the designing requirement of balanced type photo-detector circuit, but there is amplitude fluctuation in the signal time-domain curve that two cell diodes are exported separately, and the jagged appearance of the curve at crest and trough place, illustrates that two detectors all exist the amplitude noise of local oscillator light.
From Fig. 6 and Fig. 7, can see, there is a peak that amplitude is very strong in frequency-region signal, the intermediate-freuqncy signal of the 100MHz that Here it is will measure, the amplitude of the intermediate-freuqncy signal in time domain is compared obvious increase with the amplitude of single-element detector output signal, and compare time-domain curve smoother with Fig. 5 with Fig. 4, amplitude does not have the appearance of wave phenomenon, illustrates that noise has significantly reduced.
Simultaneously, in experimentation, the signal to noise ratio (S/N ratio) that has obtained respectively the heterodyne signal of the first PIN photodiode output of balanced type photodetector in the 2 mu m coherent laser windfinding radar systems of the present invention at best local oscillator luminous power place by binary data corresponding to the heterodyne signal collecting being carried out to digital signal processing is 82.15dB, the signal to noise ratio (S/N ratio) of the heterodyne signal of the second PIN photodiode output is 82.10dB, in 2 mu m coherent laser windfinding radar systems of the present invention, the signal to noise ratio (S/N ratio) of the heterodyne signal of balanced type photodetector output is respectively 87.38dB, by measurement result, can see, in 2 mu m coherent laser windfinding radar systems of the present invention, the signal to noise ratio (S/N ratio) of balanced type photodetector is compared and is exceeded 5dB with the signal to noise ratio (S/N ratio) of the detector of 2 μ m unit, the signal to noise ratio (S/N ratio) that 2 μ m balanced type detectors are described has obviously been improved, be more suitable for the detection of faint atmospheric backscatter echoed signal.Can meet the needs of 2 mu m coherent laser windfinding radar Heterodyne Detection Systems.
Embodiment two: present embodiment is that the first PIN photodiode 1, the second PIN photodiode 2, resistance R 1, resistance R 2, resistance R 3, capacitor C 1, capacitor C 2, capacitor C 3, one-level amplifier 3 and two-stage amplifier 4 are integrated in microelectronics Packaging to the further illustrating of balanced type photodetector in 2 mu m coherent laser windfinding radar systems described in embodiment one.
The advantage of this encapsulation is to reduce stray capacitance, increases the reception bandwidth of photodetector.
Embodiment three: present embodiment is to the further illustrating of balanced type photodetector in 2 mu m coherent laser windfinding radar systems described in embodiment one, described balanced type photodetector adopts InGaAs material to realize.
Claims (3)
- Balanced type photodetector in 1.2 mu m coherent laser windfinding radar systems, it is characterized in that, it comprises the first PIN photodiode (1), the second PIN photodiode (2), resistance R 1, resistance R 2, resistance R 3, capacitor C 1, capacitor C 2, capacitor C 3, one-level amplifier (3), two-stage amplifier (4), a FC/APC port (5) and the 2nd FC/APC port (6), the flashlight output port of the one FC/APC port (5) is connected with the light signal receiving end of the first PIN photodiode (1), one end of the negative electrode connecting resistance R1 of the first PIN photodiode (1), the positive pole of another termination power supply of described resistance R 1, the local oscillator optical output port of the 2nd FC/APC port (6) is connected with the light signal receiving end of the second PIN photodiode (2), one end of the anode connecting resistance R2 of the second PIN photodiode (2), the negative pole of another termination power supply of described resistance R 2, the anode of the first PIN photodiode (1), the negative electrode of the second PIN photodiode (2), one end of resistance R 3 is connected with one end of capacitor C 1 simultaneously, another termination power ground of described resistance R 3, the other end of described capacitor C 1 is connected with the amplifying signal input end of one-level amplifier (3), the amplifying signal output terminal of one-level amplifier (3) is connected with one end of capacitor C 2, the other end of capacitor C 2 is connected with the amplifying signal input end of two-stage amplifier (4), the amplifying signal output terminal of two-stage amplifier (4) is connected with one end of capacitor C 3, the other end of capacitor C 3 is the intermediate-freuqncy signal output terminal of balanced type photodetector in 2 mu m coherent laser windfinding radar systems.
- 2. balanced type photodetector in 2 mu m coherent laser windfinding radar systems according to claim 1, it is characterized in that, the first PIN photodiode (1), the second PIN photodiode (2), resistance R 1, resistance R 2, resistance R 3, capacitor C 1, capacitor C 2, capacitor C 3, one-level amplifier (3) and two-stage amplifier (4) are integrated in microelectronics Packaging.
- 3. balanced type photodetector in 2 mu m coherent laser windfinding radar systems according to claim 2, is characterized in that, described balanced type photodetector adopts InGaAs material to realize.
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| CN102914366A (en) * | 2012-10-12 | 2013-02-06 | 中山大学 | Photoelectric differential detector with high common-mode rejection ratio (CMRR) |
| CN103115635B (en) * | 2013-02-05 | 2015-03-25 | 天津大学 | Double-channel frequency division photoelectric signal detection circuit |
| CN105355704B (en) * | 2015-12-01 | 2017-06-16 | 天津飞讯伟业科技有限公司 | Symmetric double PIN balances photodetector |
| CN105652100B (en) * | 2016-02-18 | 2018-07-10 | 北京工业大学 | Photoelectric tube pulsewidth controllable measuring device and its application method |
| CN106597563B (en) * | 2017-01-10 | 2018-11-23 | 武汉大学 | A kind of Space Coupling shell-type adjustment of balance photodetector |
| CN111525898A (en) * | 2020-04-23 | 2020-08-11 | 太原理工大学 | High-gain broadband balance homodyne detector |
| CN111917485A (en) * | 2020-08-10 | 2020-11-10 | 武汉普赛斯电子技术有限公司 | Intensity modulation optical signal eye pattern measuring device and method based on linear light sampling |
| CN113740878B (en) * | 2021-09-09 | 2023-09-22 | 南京牧镭激光科技股份有限公司 | Balance detector circuit for wind-finding radar |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2241900Y (en) * | 1995-01-26 | 1996-12-04 | 邮电部广州通信设备厂 | Fireproof photoelectric detector |
| CN101825713A (en) * | 2009-12-24 | 2010-09-08 | 哈尔滨工业大学 | 2 mu m all-fiber coherent laser Doppler wind finding radar system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008526003A (en) * | 2004-12-24 | 2008-07-17 | ピレリ・アンド・チ・ソチエタ・ペル・アツィオーニ | Germanium-on-silicon photodetector |
| US20090284746A1 (en) * | 2006-07-20 | 2009-11-19 | Koninklijke Philips Electronics N.V. | Radiation detectors using evanescent field excitation |
-
2012
- 2012-06-19 CN CN201210202640.1A patent/CN102721955B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2241900Y (en) * | 1995-01-26 | 1996-12-04 | 邮电部广州通信设备厂 | Fireproof photoelectric detector |
| CN101825713A (en) * | 2009-12-24 | 2010-09-08 | 哈尔滨工业大学 | 2 mu m all-fiber coherent laser Doppler wind finding radar system |
Non-Patent Citations (1)
| Title |
|---|
| 王春晖 等.光束分束比对２μｍ平衡式相干探测***信噪比影响的实验研究.《光学学报》.2011,第31卷(第11期),第1104002-1-1104002-6页. * |
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