CN103549941B - AWG (arrayed waveguide grating) wavelength demodulation system with temperature compensation function, heartbeat detection device and application - Google Patents

Abstract

The invention discloses an AWG (arrayed waveguide grating)-based fiber bragg grating wavelength demodulation system with a real-time temperature compensation function, a heartbeat detection device and application, and belongs to the field of photoelectric detection. The wavelength demodulation system consists of an ASE (amplified spontaneous emission) broadband light source, an optical isolator, a 3dB coupler, an AWG, a temperature compensation grating, an optical detector array and a signal processing unit for implementing a wavelength demodulation algorithm, and can be used for demodulating the reflection wavelength of a fiber bragg grating. Compared with other AWG-based wavelength demodulation systems, the system has functions of automatically selecting a demodulation channel and compensating temperature in real time. The heartbeat detection device consists of the wavelength demodulation system and a fiber bragg grating heartbeat sensor, and can be used for monitoring human heartbeat signals in real time. The wavelength demodulation system has the characteristics of simple structure, small size, low cost, high detection accuracy, high demodulation speed and the like. The demodulation-system-based human heartbeat detection device can be applied to the development of optical fiber sensing smart clothing to realize the real-time and long-term monitoring of the human heartbeat signals, and is significant for the discovery and treatment of diseases such as cardiovascular diseases.

Description

There is the AWG Wavelength demodulation system of temperature-compensating and checkout gear aroused in interest and application

Technical field

The present invention relates to fiber grating sensing technology field, especially based on the Wavelength demodulation system of array waveguide grating (AWG) and checkout gear aroused in interest and application.

Background technology

Intelligent clothing refers to carry out perception to human external environment or internal state change, and by feedback mechanism, can in real time to the clothing that this change is made a response.Utilize inner integrated sensor, intelligent clothing can carry out Real-Time Monitoring to the multiple physiological parameter of human body, and does not affect the normal activity of wearer, is desirable portable physiological parameter monitoring platform.Intelligent clothing technology has broad application prospects in fields such as health supervision, tele-medicine, military sports, Aero-Space.

Intelligent clothing correlation theory and technology have become important research topic abroad, known from related data, the Main way of current research concentrates on novel physiological parameter measurement method, miniaturization and microminiaturized sensor design method, sensor and processing unit thereof and inweaves the aspects such as clothing method, and representative intelligent clothing prototype has VTAM, WEALTHY, MagIC, MyHeart prototype in Europe and the LifeShirt prototype of the U.S..China is at the early-stage in the research in health supervision type intelligent clothing field, mainly utilizes electric sensor human body physiological parameter, make in sensor design, in clothing methods implanted by sensor etc. with still have certain gap abroad.

Fiber grating (FBG) has that volume is little, lightweight, highly sensitive, electromagnetism interference, be easy to the advantages such as networking, and therefore, fiber grating is one of sensing element of most advantage and potential in intelligent clothing.Fiber grating is a kind of Fibre Optical Sensor of wavelength-modulated type, when ambient temperature or axial strain change, also will there is linear drift in the reflection kernel wavelength of fiber grating, can be realized the detection of physical quantity to external world by the change of detection of reflected wavelength thereupon.The equipment of detection fiber optical grating reflection wavelength can be called wavelength demodulation device or Wavelength demodulation system, for realizing the detection based on the human body physiological parameter of fiber grating in intelligent clothing, the research of Wavelength demodulation system is most important.

Compared with other demodulating system, based on the Wavelength demodulation system of AWG, have that volume is little, structure is simple, demodulation speed is fast, can realize the features such as distributed measurement, be applicable to being applied to the demodulation carrying out fiber grating reflection wavelength in intelligent clothing, realize the detection to human body physiological parameter.But the output characteristics of AWG is subject to the impact of temperature, there is temperature drift phenomenon in the centre wavelength of each passage output spectra, causes demodulation result to produce comparatively big error, affect certainty of measurement.Therefore how carrying out temperature-compensating is the key that AWG Wavelength demodulation system realizes high-acruracy survey.The method of the relevant AWG temperature-compensating of report both at home and abroad has at present: input waveguide position compensation, negative thermo-optical coeffecient waveguide material temperature-compensating etc. are moved in waveguide embedding compensation, bimetal leaf stress compensation, thermal expansion, but these methods are realized by the design on AWG chip structure mostly, and cost is higher.

The present invention proposes a kind of AWG Wavelength demodulation method with real-time temperature compensation function, traditional AWG Wavelength demodulation system structure is improved, by increasing temperature-compensating grating, realizing the real-time temperature compensation to sensing grating Wavelength demodulation result, improve Wavelength demodulation precision.The Wavelength demodulation system that utilization proposes and fiber grating sensor aroused in interest form human body checkout gear aroused in interest, this device can be selected automatically to the demodulation passage corresponding to fiber grating sensor aroused in interest, avoids because of the excessive problem causing demodulation method to lose efficacy of the initial wavelength variation range of fiber grating sensor aroused in interest.This checkout gear aroused in interest can be applicable to Fibre Optical Sensor intelligent clothing, realizes the Real-Time Monitoring of human body signal aroused in interest.

Summary of the invention

Technical problem to be solved by this invention is to provide a kind of AWG Wavelength demodulation system with temperature-compensating.

Another technical problem to be solved by this invention is to provide a kind of checkout gear aroused in interest applying above-mentioned Wavelength demodulation system.

Another technical problem to be solved by this invention is the application providing above-mentioned checkout gear aroused in interest.

For solving the problems of the technologies described above, technical scheme of the present invention is:

As shown in Figure 1, a kind of Wavelength demodulation system, by ASE wideband light source, optoisolator, three-dB coupler, array waveguide grating, temperature-compensating grating, photodetector array and the signal processing unit composition for realizing Wavelength demodulation algorithm, wherein ASE wideband light source successively with optoisolator, first port of three-dB coupler is connected, the 3rd of described bonder, four ports respectively sensor aroused in interest with fiber grating are connected with temperature-compensating grating, second port of described bonder successively with array waveguide grating, photodetector array and signal processing unit input port connection, described temperature-compensating grating and array waveguide grating are in same temperature field.

Preferably, above-mentioned Wavelength demodulation system, described signal processing unit is made up of I/V translation circuit, amplifying circuit, MCU chip, wherein I/V translation circuit successively with the analog/digital conversion input port connection of amplifying circuit and MCU chip, described MCU chip exports restituted signal by D/A switch output port and serial communication interface.

Preferably, above-mentioned Wavelength demodulation system, described I/V translation circuit and amplifying circuit form signal conditioning circuit jointly, and operational amplifier model selected by this signal conditioning circuit is OPA129, OPA4227 or OPA2227.

Preferably, above-mentioned wavelength mediation system, described MCU chip model is STM32F103ZET6.

Preferably, above-mentioned wavelength mediation system, described signal processing unit realizes Wavelength demodulation by following method: the reflected light of fiber grating through coupler transfer to AWG, the demodulation passage (the AWG passage adjacent with fiber bragg grating center wavelength) of AWG exports light and imports photo-detector into, photo-detector enters modulate circuit after light intensity signal is converted to current signal, modulate circuit output voltage signal is undertaken sampling by MCU chip and performs the AWG Wavelength demodulation algorithm with temperature compensation function, calculates the centre wavelength of tested grating.

Preferably, above-mentioned Wavelength demodulation system, by a bare optical fibers and bare optical gratings as temperature-compensating grating, be affixed on AWG surface to make it to be in same temperature field with AWG, this null grating is utilized to obtain the temperature of AWG, temperature according to AWG is revised the correlation coefficient in Wavelength demodulation formula, thus eliminates because the variations in temperature of AWG is on the impact of demodulation result, improves the accuracy of wavelength detecting.

Preferably, above-mentioned wavelength mediation system, realizes temperature-compensating by following method:

The demodulation formula of sensing grating centre wavelength is:

λ _B=M·ρ+N(T) (1)

Wherein, λ _bfor sensing grating centre wavelength, ρ is the natural logrithm value of the adjacent output channel of sensing grating corresponding A WG (i.e. demodulation passage) output intensity ratio, T is the temperature of AWG, M is constant, relevant with device parameters, N is penalty coefficient, its value is relevant with the temperature of AWG, the reflected light of null grating is through bonder, AWG and modulate circuit export signal processing unit to, calculate the natural logrithm value ρ ' of the AWG two adjacency channel output intensity ratio corresponding to null grating, the relational expression of ρ ' being brought into T and the ρ obtained by experiment ' obtains the temperature of current AWG, the computing formula of again T being brought into N (T) obtains the N value in formula (1), thus the real-time temperature compensation realized demodulation result.

Apply a checkout gear aroused in interest for above-mentioned wavelength mediation system, this device can realize the automatic selection of sensing grating demodulation passage, realizes the Real-Time Monitoring to human body signal aroused in interest.

Preferably, above-mentioned checkout gear aroused in interest, the 3 port connecting fiber grating sensor aroused in interest of the three-dB coupler in accompanying drawing 1, realizes the detection of human body signal aroused in interest by the wavelength change of detection fiber grating sensor aroused in interest.

Preferably, above-mentioned checkout gear aroused in interest, described signal processing unit realizes the automatic selection of sensing grating demodulation passage by following method: be chosen at may be crossing with fiber grating center sensor aroused in interest wavelength in testing process aroused in interest three AWG output channels, signal processing unit is sampled to this three paths output intensity at every turn, the adjacent two paths selecting wherein light intensity larger is as sensing grating Wavelength demodulation passage, the centre wavelength of fiber grating sensor aroused in interest is calculated according to Wavelength demodulation formula and temperature compensation algorithm, obtain human body information aroused in interest, thus avoid because the excessive demodulating algorithm that causes of the initial wavelength variation range of fiber grating sensor aroused in interest lost efficacy.

The application of above-mentioned checkout gear aroused in interest in intelligent clothing.

Beneficial effect of the present invention: Wavelength demodulation system structure of the present invention is simple, volume is little, demodulation speed is fast, has real-time temperature compensation function, avoids AWG variations in temperature on the impact of demodulation result, improves wavelength detecting precision.The checkout gear aroused in interest applying above-mentioned wavelength mediation system can realize the detection of human body signal aroused in interest, automatically can select the demodulation passage of AWG according to the wavelength change of fiber grating sensor aroused in interest, there is the features such as volume is little, cost is low, detection sensitivity is high, practical; The intelligent clothing applying above-mentioned checkout gear aroused in interest can carry out Real-Time Monitoring to human body signal aroused in interest, realize the early discovery to cardiovascular disease, thus patient is given treatment in time, reduce mortality risk, have great importance in clinical treatment and house health supervision etc.In addition, above-mentioned intelligent clothing can also be applied to the fields such as military and space flight, amusement and communication, safety and defendance, has higher economic benefit.

Accompanying drawing explanation

Fig. 1 is Wavelength demodulation system theory diagram;

Fig. 2 is the composition frame chart of signal processing unit;

Fig. 3 is checkout gear aroused in interest actual measurement human body signal waveforms aroused in interest.

Detailed description of the invention

Below in conjunction with specific embodiment, technical scheme of the present invention is further described.

Embodiment 1

As shown in Figure 1, a kind of Wavelength demodulation system, by ASE wideband light source, optoisolator, three-dB coupler, array waveguide grating, temperature-compensating grating, photodetector array and the signal processing unit composition for realizing Wavelength demodulation algorithm, wherein ASE wideband light source successively with optoisolator, first port of three-dB coupler is connected, the 3rd of described bonder, four ports respectively sensor aroused in interest with fiber grating are connected with temperature-compensating grating, second port of described bonder successively with array waveguide grating, photodetector array and signal processing unit input port connection, as shown in Figure 2, photodetector output signal enters I/V translation circuit, I/V translation circuit successively with amplifying circuit and MCU chip inner analog/digital conversion module input mouth connection, the inner D/A switch module of described MCU chip and buffer circuit connection, restituted signal is exported with analog voltage form, the inner serial port module of described MCU chip and level shifting circuit connection, export restituted signal in digital form.

The operation principle of described Wavelength demodulation system is as follows:

AWG Wavelength demodulation algorithm requires that the change of sensing grating centre wavelength is between the centre wavelength of adjacent two channel transfer spectrum of AWG.By calculating the intensity signal of adjacent two AWG output channels, obtain the centre wavelength of corresponding sensing grating.

Specific algorithm is as follows:

The reflectance spectrum function of sensing grating is:

R _FBG(λ)=R ₀exp[-4(ln2)×(λ-λ _B) ²/Δλ _B ²] (2)

Wherein, R ₀for sensing grating reflectance, λ _bfor sensing grating centre wavelength, Δ λ _bfor sensing grating half-peak band width (FWHM).

AWG two output channel adjacent with sensing grating centre wavelength is set to passage i and i+1, and the transmission spectrum function of passage i is:

T _AWG(i，λ)=T _iexp[-4(ln2)×(λ-λ _i) ²/Δλ _i ²] (3)

Wherein, T _ifor the max transmissive coefficient of passage i, λ _ifor the centre wavelength of passage i, Δ λ _ifor the half-peak band width of passage i.If channel spacing Δ λ=Δ λ _i+1-Δ λ _i, and equal.

The then output intensity P of passage i _ican be expressed as:

$\begin{array}{c}{P}_i=(1-L_i){\∫}_0^{+\∞}S\left(\mathrm{\λ}\right)T_{\mathrm{AWG}}(i,\mathrm{\λ})R_{\mathrm{FBG}}\left(\mathrm{\λ}\right)\mathrm{d\λ}\\ =(1-L_i)S_0{R}_0{T}_i\mathrm{\Δ}{\mathrm{\λ}}_B\mathrm{\Δ}{\mathrm{\λ}}_i\sqrt{\mathrm{\π}/4\left(\ln 2\right)(\mathrm{\Δ}{{\mathrm{\λ}}_B}^2+\mathrm{\Δ}{{\mathrm{\λ}}_i}^2)}\\ \×\exp [-4\left(\ln 2\right)\×{({\mathrm{\λ}}_B-{\mathrm{\λ}}_i)}^2/(\mathrm{\Δ}{{\mathrm{\λ}}_B}^2+\mathrm{\Δ}{{\mathrm{\λ}}_i}^2)\end{array}---\left(4\right)$

Wherein, S (λ) is light source output power spectrum, supposes that output is constant S in AWG bandwidth ₀, L _ifor attenuation coefficient.

In like manner, the output intensity P of passage i+1 _i+1can be expressed as:

$\begin{array}{c}{P}_{i+1}=(1-L_{i+1}){\∫}_0^{+\∞}S\left(\mathrm{\λ}\right)T_{\mathrm{AWG}}(i+1,\mathrm{\λ})R_{\mathrm{FBG}}\left(\mathrm{\λ}\right)\mathrm{d\λ}\\ =(1-L_{i+1})S_0{R}_0{T}_{i+1}\mathrm{\Δ}{\mathrm{\λ}}_B\mathrm{\Δ}{\mathrm{\λ}}_{i+1}\sqrt{\mathrm{\π}/4\left(\ln 2\right)(\mathrm{\Δ}{{\mathrm{\λ}}_B}^2+\mathrm{\Δ}{{\mathrm{\λ}}_{i+1}}^2)}\\ \×\exp [-4\left(\ln 2\right)\×{({\mathrm{\λ}}_B-{\mathrm{\λ}}_{i+1})}^2/(\mathrm{\Δ}{{\mathrm{\λ}}_B}^2+\mathrm{\Δ}{{\mathrm{\λ}}_{i+1}}^2)\end{array}---\left(5\right)$

Suppose Δ λ _i+1-Δ λ _i< < Δ λ _b, AWG each channel transfer coefficient, half-peak band width are all equal, then the natural logrithm ρ of passage i+1 and passage i output intensity ratio can be expressed as:

$\mathrm{\&rho;}=\ln \left(\frac{P_{i+1}}{P_i}\right)=\frac{8\left(\ln 2\right)\mathrm{\&Delta;\&lambda;}}{\mathrm{\&Delta;}{{\mathrm{\&lambda;}}_i}^2+\mathrm{\&Delta;}{{\mathrm{\&lambda;}}_B}^2}{\mathrm{\&lambda;}}_B-\frac{4\left(\ln 2\right)({{\mathrm{\&lambda;}}_{i+1}}^2-{{\mathrm{\&lambda;}}_i}^2)}{\mathrm{\&Delta;}{{\mathrm{\&lambda;}}_i}^2+\mathrm{\&Delta;}{{\mathrm{\&lambda;}}_B}^2}---\left(6\right)$

Visible, ρ and sensing grating reflection wavelength linear, the reflection wavelength of sensing grating can be gone out by backstepping by calculating ρ.Through arranging, AWG Wavelength demodulation formula is:

$\begin{array}{c}{\mathrm{\&lambda;}}_B=\frac{\mathrm{\&Delta;}{{\mathrm{\&lambda;}}_i}^2+\mathrm{\&Delta;}{{\mathrm{\&lambda;}}_B}^2}{8\left(\ln 2\right)\mathrm{\&Delta;\&lambda;}}\&CenterDot;\mathrm{\&rho;}+\frac{{\mathrm{\&lambda;}}_{i+1}+{\mathrm{\&lambda;}}_i}{2}\\ =M\&CenterDot;\mathrm{\&rho;}+N\end{array}---\left(7\right)$

Wherein, M is constant, composes half-peak band width, AWG channel spacing is relevant with AWG output spectra and tested optical grating reflection.N is relevant with the centre wavelength of tested grating demodulation passage, and change due to the change of AWG output channel center wavelength with temperature, therefore N changes with the temperature T of AWG.In temperature compensation algorithm of the present invention, N is called penalty coefficient, according to the real-time regulating parameter N of the temperature of AWG, thus realizes temperature-compensating.

Embodiment 2

As shown in Figure 1, described Wavelength demodulation system utilizes temperature-compensating grating to realize temperature-compensating, avoids AWG variations in temperature on the impact of sensing grating demodulation result.Temperature-compensating grating is affixed on AWG surface, and the natural logrithm value ρ ' of the AWG adjacency channel beam intensity ratio of being answered by temperature-compensating grating pair can calculate the temperature T of AWG, and experimental result shows that T and ρ ' meets following relational expression:

T=a ₁+a ₂ρ′+a ₃ρ′ ²(8)

Wherein, a ₁, a ₂, a ₃relevant with device parameters, obtain by experiment.Coefficient N and T in formula (7) is linear relationship, and its expression formula is:

N=b ₁+b ₂T (9)

Wherein, b ₁, b ₂value obtains by experiment.T is brought into formula (9) and the current penalty coefficient N of demodulation formula (7) can be calculated, natural logrithm value ρ and the penalty coefficient N of the AWG adjacency channel beam intensity ratio of then being answered by tested grating pair bring formula (7) into, calculate the centre wavelength of tested grating, realize real-Time Compensation AWG variations in temperature being caused to wavelength measurement error, improve accuracy of detection.

Embodiment 3

For verifying the correctness of the temperature compensation algorithm proposed, the centre wavelength of above-mentioned Wavelength demodulation system to fiber-optic grating sensor is utilized to detect, change AWG temperature and tested raster center wavelength, record adds backoff algorithm and does not add the demodulation result of compensation, experimental result is as shown in table 1 (wherein, FBG is the exact value of tested grating wavelength, FBG ₁for not adding demodulation result during temperature compensation algorithm, FBG ₂for adding demodulation result during temperature compensation algorithm, error 1 is demodulating error when not adding backoff algorithm, and error 2 is for adding the demodulating error after backoff algorithm).In this experimental result, the demodulation result mean error not adding temperature compensation algorithm is 11.1pm, adding the demodulation result mean error after temperature compensation algorithm is 2.7pm, thus demonstrate the accuracy of detection that proposed temperature compensation algorithm can improve AWG Wavelength demodulation system effectively, reduce the wavelength error due to the introducing of AWG variations in temperature.

Table 1 temperature compensation algorithm confirmatory experiment measurement data

FBG(nm)	FBG 1(nm)	FBG 2(nm)	Error 1 (pm)	Error 2 (pm)
					1548.1233	1548.1197	1548.1249	3.6	1.6
1548.2449	1548.2413	1548.2419	3.6	3
					1548.2909	1548.2764	1548.2877	14.5	3.2
1548.2934	1548.2790	1548.2926	14.4	0.8
					1548.3074	1548.2934	1548.3028	14	4.6
1548.3125	1548.3011	1548.3093	11.4	3.2
					1548.3346	1548.3186	1548.3321	16	2.5

Application examples

Utilize above-mentioned checkout gear aroused in interest to carry out human body signal actual measurement aroused in interest, and carry out wavelet noise process to the signal aroused in interest demodulated, the signal aroused in interest finally obtained as shown in Figure 3.Experimental result shows: described fiber grating checkout gear aroused in interest can realize the correct collection of human body signal aroused in interest, Wavelength demodulation signal can obtain the good signal aroused in interest of signal to noise ratio after wavelet Based on Denoising Algorithm process, thus realizes the real-time detection to human body signal aroused in interest.

Above-mentioned have to this detailed description that AWG Wavelength demodulation system of temperature-compensating and checkout gear aroused in interest and application carry out with reference to embodiment; illustrative instead of determinate; several embodiments can be listed according to institute's limited range; therefore in the change do not departed under general plotting of the present invention and amendment, should belong within protection scope of the present invention.

Claims (10)

1. a Wavelength demodulation system, it is characterized in that: by ASE wideband light source, optoisolator, three-dB coupler, array waveguide grating, temperature-compensating grating, photodetector array and the signal processing unit composition for realizing Wavelength demodulation algorithm, wherein ASE wideband light source successively with optoisolator, first port of three-dB coupler is connected, the 3rd of described bonder, four ports respectively sensor aroused in interest with fiber grating are connected with temperature-compensating grating, second port of described bonder successively with array waveguide grating, photodetector array and signal processing unit input port connection, described temperature-compensating grating and array waveguide grating are in same temperature field.

2. Wavelength demodulation system according to claim 1, it is characterized in that: described signal processing unit is made up of I/V translation circuit, amplifying circuit, MCU chip, wherein I/V translation circuit successively with the analog/digital conversion input port connection of amplifying circuit and MCU chip, described MCU chip exports restituted signal by D/A switch output port and serial communication interface.

3. Wavelength demodulation system according to claim 2, is characterized in that: described I/V translation circuit and amplifying circuit form signal conditioning circuit jointly, and operational amplifier model selected by this signal conditioning circuit is OPA129, OPA4227 or OPA2227.

4. Wavelength demodulation system according to claim 2, is characterized in that: described MCU chip model is STM32F103ZET6.

5. according to the Wavelength demodulation system one of claim 1-4 Suo Shu, it is characterized in that: described signal processing unit realizes Wavelength demodulation by following method: the reflected light of fiber grating through coupler transfer to AWG, the AWG passage adjacent with fiber bragg grating center wavelength exports light and imports photo-detector into, photo-detector enters modulate circuit after light intensity signal is converted to current signal, modulate circuit output voltage signal is undertaken sampling by MCU chip and performs the AWG Wavelength demodulation algorithm with temperature compensation function, calculates the centre wavelength of tested grating.

6. according to the Wavelength demodulation system one of claim 1-4 Suo Shu, it is characterized in that: by a bare optical fibers and bare optical gratings as temperature-compensating grating, be affixed on AWG surface to make it to be in same temperature field with AWG, this null grating is utilized to obtain the temperature of AWG, temperature according to AWG is revised the correlation coefficient in Wavelength demodulation formula, thus eliminate because the variations in temperature of AWG is on the impact of demodulation result, improve the accuracy of wavelength detecting.

7. according to the Wavelength demodulation system one of claim 1-4 Suo Shu, it is characterized in that: described Wavelength demodulation system realizes temperature-compensating by following method:

Sensing grating centre wavelength demodulation formula is:

λ _B＝M·ρ+N(T) (1)

Wherein, λ _bfor sensing grating centre wavelength, ρ is the natural logrithm value of the adjacent output channel output intensity ratio of sensing grating corresponding A WG, T is the temperature of AWG, M is constant, relevant with device parameters, N is penalty coefficient, its value is relevant with the temperature of AWG, the reflected light of null grating is through bonder, AWG and modulate circuit export signal processing unit to, calculate the natural logrithm value ρ ' of the AWG two passage output intensity ratio corresponding to null grating, the relational expression of ρ ' being brought into T and the ρ obtained by experiment ' obtains the temperature of current AWG, the computing formula of again T being brought into N (T) obtains the N value in formula (1), thus the real-time temperature compensation realized demodulation result,

The relational expression of described T and ρ ' is:

T＝a ₁+a ₂ρ′+a ₃ρ ¹²

Wherein, a ₁, a ₂, a ₃relevant with device parameters, obtain by experiment;

The computing formula of described N (T) is:

N＝b ₁+b ₂T

Wherein, b ₁, b ₂value obtains by experiment.

8. the human body checkout gear aroused in interest of the described Wavelength demodulation system of one of application rights requirement 1-7, it is characterized in that: the 3 port connecting fiber grating sensor aroused in interest of three-dB coupler, sensor aroused in interest for fiber grating is placed on human body detection position aroused in interest, is realized the detection of human body signal aroused in interest by the change of detection fiber grating sensor aroused in interest output wavelength.

9. human body according to claim 8 checkout gear aroused in interest, it is characterized in that: described signal processing unit realizes the automatic selection of sensing grating demodulation passage by following method: be chosen at may be crossing with fiber grating center sensor aroused in interest wavelength in testing process aroused in interest three AWG output channels, signal processing unit is sampled to this three paths output intensity at every turn, the adjacent two paths selecting wherein light intensity larger is as sensing grating Wavelength demodulation passage, the centre wavelength of fiber grating sensor aroused in interest is calculated according to Wavelength demodulation formula and temperature compensation algorithm, obtain human body information aroused in interest, thus avoid because the excessive demodulating algorithm that causes of the initial wavelength variation range of fiber grating sensor aroused in interest lost efficacy.

10. the application of human body checkout gear aroused in interest in intelligent clothing that one of claim 8-9 is described.