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The electro-optic modulation technique based on the crystal electro-optic effect of the physical basis of light corresponding parameter modulation technology, mainly used in the field of optical communications, lithography and laser radar. Generally used in space optical communication, laser as a means of information transmission, high-power, high-rate electro-optic modulation technique is an important research of space optical communication field, has become one of the bottlenecks restricting the research and development of China's space optical communication. At present, the world's scientific and technological power attaches great importance to the special military value of space optical communication, has launched a space optical communication and its key technology research, and promote it to a higher strategic position. Optical communication can be divided into two major categories of optical fiber communication and space optical communication, both on the principle of electro-optic modulator, methods, parameters, indicators are not the same. At present, high-speed electro-optic modulation technique has earlier and widely used in the field of optical fiber communication, developing very rapidly. High rate of electro-optic modulator for 1550nm band laser the integrated waveguide modulation, modulation bandwidth up to 160GHz, the communication rate of 40Gbps optical fiber communication system has been commercialized. In free space, near space, waited in vain for deep-link space laser communication, China's high-power electro-optic modulator technology research is lagging behind. Space optical communication using a laser of 800nm ??band, this band laser in atmospheric channel transmission having a \Space laser communication link distance is very far, laser transmission loss in the atmospheric channel, so in need of electro-optic modulator output optical power in the order of magnitude of a few hundred mW or W, which is a high-speed electro-optic modulator in optical fiber communication The device can not be achieved. In order to ensure the needs of the large volume of information transmission, the space laser communication electro-optic modulator must be a tradeoff between power and rate indicators, the modulation rate generally require hundreds of Mbps to Gbps. At present, the research group carried out a total of two methods. One method is the use of high-power, high-speed direct modulation rate of electro-optic modulation technique to meet the space laser communication needs electro-optic modulator, 800nm ??band, consider this band more optical devices, the technology is relatively mature and atmospheric low loss characteristics, work in this area and this thesis has been made in the \used in space laser communication experiment. Method is the use of the existing high-speed optical fiber communication rate modulation technique for low-loss optical fiber 1550nm band, to carry out follow-up study of the optical amplification technology, and strive developed to meet the distance near space or deep-space laser communication needs of large power, high-speed integrated laser transmitter module, research in this area is expected to be able to make a breakthrough in the \This thesis is based on research methods, the seven issues to be addressed: (1) how to improve the optical power output and modulation rate; (2) how to reduce the half-wave voltage; (3) how to design and production of electrodes; (4) modulator drive signal; (5) how to achieve automatic control of the quiescent operating point; (6) how to design engineering prototype; (7) how to carry out testing and application experiments. In order to solve the above problems, the main research work is broken down into the following aspects: (1) in-depth research of the research status, analyze and summarize the existing research results; (2) to improve the output optical power of electro-optic modulator, a pulse encoder modulation, intensity modulation, lateral modulation and body modulation modulation scheme, relative to the integrated waveguide modulation scheme is relatively easy to achieve, does not require very demanding waveguide design process; (3) in order to improve the electro-optic modulation of the output light power, consider a crystal anti- photodamage ability to consider a compromise crystal size, aspect ratio and aperture, the design of efficient optical structure, the design of long-path self-focusing lens, collimator and efficient fiber coupling; (4) increase modulation rate and reduce the half-wave voltage, a detailed analysis of the structure and characteristics of the lithium niobate crystal, double-crystal series combination of modulation and transverse traveling wave modulation; (5) to carry out the design of the traveling wave electrode, production technology and processes; (6) electro-optical modulator drive signal has a frequency band, carried out based on the existing radio frequency integrated amplifier two pieces of negative feedback amplifier technology for this purpose; (7) In order to overcome the temperature, refraction rate changes and other effects, to carry out the quiescent operating point automatic control, temperature control, frequency stability and other studies; (8) in the engineering prototype design: to carry out the crystal size, from the polarizer and analyzer parameters, self-focusing lens, the optical path structure electrode, the mechanical structure, miniaturization, etc.; (9) in the room: mainly carried out wavelength, optical power and modulation bandwidth test, and to carry a digital signal transmission experiment; (10) carried out the optical power in the wild: budget, power loss, communication rate, and bit error rate and other research and testing, analysis of the effect of experimental verification. The paper to carry out a high-power, high-rate theoretical analysis of the electro-optical modulation techniques, simulation studies, engineering prototype design and application of experimental studies, the experimental data has good support and validation of theoretical research. With the planning and development of China's \High-power, high-speed electro-optic modulation technology research and findings will play a certain role in promoting the use and development of space optical communication in the future.
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