With the problem of small field of view, high precision and difficulty in alignment for portable laser communication, the method and device based on measuring field of view in portable laser communication are designed and proposed. By calculating the link energy under the specified communication distance, the energy range of extensible field of view can be obtained. A high precision measuring device is designed. The actual test was carried out. The result shows that the receiving field of view for portable laser communication is 0.63mard under the condition of 1km communication distance and the sensitivity of detector -30dBm. The field of view for portable laser communication can be accurately measured by the test method and device. The test device can extend the measuring range of small field of view in different fields.
The influence of the alignment error in laser communication is analyzed. The link energy model with the position deviation at the image surface is established, and on the basis of this model, the spot deviation and the receiving optical axis deviation caused by the angular deviation of the optical axis are discussed and analyzed. Under the conditions of initial transceiver parameters, the link energy and the allowable maximum angle deviation with the distance of 0~2km are further calculated. The model formula of alignment error can be applied to analysis and discussion under the father distance. It has a theoretical guiding significance for the field laser communication test.
Demanding for the closed communication among urban buildings, a solution for close range laser communication is proposed. The functional composition of the system is demonstrated and analyzed and the parameters of the system are reasonably allocated. The system design is used with independent optical aperture. The energy model under the inherent error of transceiver is analyzed and calculated. On the basis, the actual communication test was carried out, the specific test operation process is given and the measured data are obtained. The deviation between the average data and the theory is not more than 0.58dB. The correctness of the theoretical energy model is verified. The energy model can be used to guide the design of remote distance communication terminal. At the same time, the successfully development and communication test can be effectively accelerated the application of civil communication for urban buildings.
In order to analysis and design the Czerny-Turner structure spectrometer with the high resolution and high energy reception, various astigmatism methods of the Czerny-Turner structure are reported. According to the location of plane grating, the astigmatism correction methods are divided into two categories, one is the plane grating in divergent illumination, another is the plane grating in parallel illumination. Basing on the different methods, the anastigmatic principle and methods are analyzed, the merits and demerits of the above methods are summarized and evaluated. The theoretical foundation for design of broadband eliminating astigmatism Czerny-Turner spectrometer and the reference value for the further design work are laid by the summary and analyzing in this paper.
In order to break through the laser communication technology of one point to multipoint, which is the difficult problems for laser communication. The networking solutions of the antenna structure of three concentric spheres are proposed. Being with the advantages of simple structure, small size and light weight, the antenna structure of three concentric spheres can be applied to short-distance space laser communication. The feasibility of the system can be realized from two aspects, the analysis of link and the analysis of the precision index. On this basis, the whole optical system can be determined by the corresponding optical system design. Under the condition of permitting of link energy, the optical system of antenna structure of three concentric spheres with mobile field azimuth angle of 120°and the pitching angle of 20°is completed. The parameters can meet the requirements in the subsystem of the communication receiving optical path, the communication transmitting optical path and the communication tracking optical system. The results indicate that the antenna structure of three concentric spheres can be applied to the laser communication networking under the short-distance space.
Thermal properties of diffractive optical element and method of design athermal hybrid infrared optical system are introduced. Athermal LWIR hybrid infrared optical system for no cooled staring detector is designed. The system consists of three lenses, the effective focal length is 100mm，the relative aperture is 1:1,the wavelength spectrum is 8~11μm, the field view is 14° and the total optical length is just 140mm. The result shows that the modulation transformation function at 17lp/mm is greater than 0.6 between -40-60°C，which prove that the system can work correctly at a large temperature range.
A Brillouin-Erbium multi-wavelength tunable fiber laser at C-band is demostrated. A 10 km long singlemode
fiber(SMF), a 6 m long Erbium-doped fiber, two couplers, a wavelength division multiplexer, a isolator, an
optical circulator, a 980nm pump laser and a narrow linewidth tunable laser are included in the structure. A segment
of 10 km-long single-mode fiber (SMF) between the two ports of a 1×2 coupler is used as Brillouin gain. Ebiumdoped
fiber amplifier（EDFA） consists of a segment of 6m er-doped fiber pumped by 980nm laser dioder . A
narrow linewidth tunable laser from 1527 to 1607 nm as Brillouin bump, At the Brillouin pump power of 8mW and
the 980 nm pump power of 400 mw, 16 output channels with 0.08 nm spacing and tuning range of 40 nm from 1527
nm to 1567 nm are achieved. We realize the tunable output of wavelength by adjusting the 980 nm pump power and
the Brillouin pump wavelength. Stability of the multiwavelength fiber laser is also observed.
A tunable multi-wavelength Brillouin fiber laser with double Brillouin frequency
spacing based on a four-port circulator is experimentally demonstrated. The fiber laser
configuration formed by four-port circulator isolates the odd-order Brillouin stokes signal to
circulate within the cavity only. In addition, it also allows propagation of the incoming Brillouin
pump and even-order Stokes signals from four-port circulator to output coupler .A L-band erbiumdoped
fiber (EDF) with 1480nm pump is used to amplify Stokes signals and to get more output
channels. At the Brillouin pump power of 8dBm and the 1480 nm pump power of 200mw, 5
output channels with double Brillouin frequency spacing and tuning range of 20 nm from 1568nm
to 1588nm are achieved.
Objective: In the field of computer vision, the technology for the automatic recognition of coded pattern plays an important basic role in the camera calibration process of intrinsic and extrinsic parameters, the binocular image matching process and the three-dimensional reconstruction process. Therefore, in the measurement processing, the successive rate for the automatic recognition of coded pattern must be guaranteed. Method: According to analyzing the geometric information of the coded pattern (the mixed type) and basing on the existing recognition method, a new automatic recognition method is proposed, which is the effective method to solve the multi-points recognition in single image by taking the multi-feature information of the coded pattern as the recognition criteria. Result: Both the new recognition method and the old recognition method are used in identifying the one hundred coded pattern which have been actually collected. The experimental result shows that, not only the new recognition method can achieve accurate identification of coded pattern with the recognition accuracy rate of 100%, but also its processing speed is 2.38 times faster than that in the old recognition method. Conclusion: It is obvious that there are many advantages in the new automatic recognition method, including the high effective recognition, the faster executive speed and independent on the auxiliary decoding process information. The new recognition method of multi-criteria combination can provide a strong guarantee for the realization of every aspect in the work of photogrammetry.
In order to provide a set of field test equipment for the infrared system of modern weapon equipments and other optics instruments, a set of large-scale resistance-type infrared target system was designed. First, the large-scale infrared target was designed in modular construction. It was decomposed into several independent and controllable units. Then the working principle of the system was introduced. Three modes of thermal exchange (conduction, convection and radiation) and the computing methods for each mode were given under thermal equilibrium conditions through modeling and simulating. Periphery electro-circuit and control software were carried out as well. Finally, the performance of the system was tested. Meanwhile novel ways of temperature compensation to improve the uniformity of the surface temperature of the target was introduced. The experimental results show that the infrared target could meet test requirements for infrared imaging weaponry which wavelengths from 8 μm to 14 μm. The temperature control precision can reach 0.5ms. In conclusion, the infrared target system can satisfy requirements of reliability, high precision, as well as strong anti-jamming and stabilization.
The intelligent control of simulation target with infrared imaging target in the indoor and outdoor
environment can effectively and quantitatively evaluated the parameters such as the minimum resolution
temperature difference（MRTD）and spatial resolution of airborne forward looking infrared, infrared detection
and tracking, infrared alarm, and etc.
This paper focused on introducing the working principles of the intelligent control simulation target of
Infrared imaging target, studying the thermal radiation characteristics of the infrared target surface material,
analyzing the influences of the infrared radiation energy distribution, and developing the intelligent control
simulation target with IR imaging target for hardware-in-the-loop simulation test. The intelligent control
simulation target which area was 5 ㎡ and concluded 44 infrared targets including two kinds of infrared
targets ,0.25ｍ×0.25ｍ, and 0.25m×0.5m, achieved 1℃～10℃ temperature simulation of target and the
background, and temperature control precision better than 0.5℃. Field test requirements were achieved by
Ultraviolet (UV) scattering communication is a broadcast communication mode of information transmission by particles
in the atmosphere scattering effect on the blind band ultraviolet light, there are many advantages such as unaffected by
electromagnetic radiation, good confidentiality, non-line-of sight communication. This type communication mainly used
in a short distance, secure communication, which was superior to no line communication in aspect of anti-jamming and
secrecy. Firstly the military requirement of UV scattering communication is analyzed in this paper, The development
trend is introduced, then the composition and working principle of ultraviolet scattering communication system are also
discussed, The key influential factors of UV communication system path transmission loss effects on parameters such as
receiver, transmitter and received beam divergence angle, pitch angle and the communication distance were analyzed.
Attenuation was quantitatively simulated under different atmospheres, communication patterns and structure parameters.
The results show that: transmission distance increases with increasing beam divergence angle and decreasing field angle.
And the received view angle of influence on the communication distance is far greater than the emission beam
divergence angle; transmission distance increases with increasing beam divergence angle and decreasing field and field
angle effects on communication distance is greater than beam divergence angle.
The Hardware-in-the-loop(HWIL) simulation test is one of the important parts for the development and performance
testing of semi-active laser-guided weapons. In order to obtain accurate results, the confidence level of the target
environment should be provided for a high-seeker during the HWIL simulation test of semi-active laser-guided weapons, and one of the important simulation parameters is the laser energy characteristic. In this paper, based on the semi-active laser-guided weapon guidance principles, an important parameter of simulation of confidence which affects energy characteristics in performance test of HWIL simulation was analyzed. According to the principle of receiving the same energy by using HWIL simulation and in practical application, HWIL energy characteristics simulation systems with the crystal absorption structure was designed. And on this basis, the problems of optimal design of the optical system were also analyzed. The measured results show that the dynamic attenuation range of the system energy is greater than 50dB, the dynamic attenuation stability is less than 5%, and the maximum energy changing rate driven by the servo motor is greater than 20dB/s.
A dual-band infrared optical system adopting an uncooled LW infrared detector and a cooled MW infrared detector is
designed and manufactured, based on the athermal ability and special diffractive properties of harmonic diffractive
elements. The design shows in the MW IR band the F/# is 2 and the focal length is 72 mm, for the temperature range -40
°C ~ 70°C the MTF value is over 0.4 at 20 lp/mm; while in the LW IR band the F/# is 1 and the focal length is 114 mm,
for the temperature range -40° ~ 70° the MTF value is over 0.5 at 10 lp/mm. Finite element method is applied to the
opto-mechanic structure of the system for thermal analysis, which confirms the imaging ability of the system in a wide