Bøger af Jianjun Zhang

LASER INTER-SATELLITE LINKS TECHNOLOGY State of the art resource covering key technologies and related theories of inter-satellite links Laser Inter-Satellite Links Technology explores satellite networking as a growing topic in the field of communication technology, introducing the definition, types, and working frequency bands of inter-satellite links, discussing the number of orbital elements of the spacecraft motion state under two-body motion and their conversion relationship, and establishing the basic demand model for inter-satellite link network, chain topology model, and transmission protocol model. The book focuses on the analysis and introduction of the principles and error sources of microwave and laser inter-satellite ranging, including the basic composition, workflow, and constraints of the laser inter-satellite link, and related design principles of the inter-satellite laser transmitter and receivers. Later chapters also discuss theories and methods of acquisition, alignment, and tracking, the impact of alignment errors on performance, and inter-satellite link modulation and its implementation. Specific sample topics covered in Laser Inter-Satellite Links Technology include: Pulse position modulation (PPM), differential pulse position modulation (DPPM), digital pulse interval modulation (DPIM), and double-head pulse interval modulation (DH-PIM) Basic demand model of inter-satellite link network application, including basic configuration of constellations and inter-satellite transmission networks Inter-satellite ranging accuracy, principles of microwave inter-satellite ranging, and analysis of microwave ranging error sources Effect of tracking error on the beam distribution at the receiving end and influence of tracking and pointing error on communication error rate Laser Inter-Satellite Links Technology serves a completely comprehensive resource on the subject and is a must-have reference for experts and scholars in aerospace, along with graduates and senior undergraduates in related programs of study.

This book helps to solve the problems and challenges of satellite sensing in the current environment of increasing communications bandwidths and multiplicity of electromagnetic signals. It presents technology that makes full use of the broadband low-loss advantages of optoelectronic technology and research into new broadband radio-frequency channelization and receiving technology based on photoelectric sensing.The methods presented allow improvements in system performance in terms of receiving bandwidth, frequency-sensing accuracy, channel equalization, adjacent channel crosstalk, dynamic range, and complexity of the system structure. In addressing the difficulty of satellite spectrum control, including the issue of high-precision and real-time wide-spectrum sensing not being able to be obtained simultaneously, the book solves the problem of accurate and parallel-decomposition sensing technology using the dual-phase optical frequency comb. This method avoids the involvement of fine filtering and does not require fine alignment between the source and the filter but achieves high perceptual accuracy.Satellite Photoelectric Sensing Technology explores the research background, significance, and current challenges associated with the technology, making it relevant and interesting to academics, practitioners, and postgraduate students in this field.