低截获混合扩频发射机的设计与实现-空间信息科学技术专业论文.docxVIP

万方数据 万方数据 摘要 基于直接序列扩频、多进制扩频以及跳频的混合扩频系统具有较强的抗截获 和抗干扰能力，本文完成了低截获混合扩频系统发射机的方案设计、硬件平台设 计以及相关模块的 FPGA 实现，主要内容如下： 1、介绍了混合扩频系统的原理，对结合 RS 纠错编码的多进制扩频系统进行 仿真，利用多相滤波器技术实现了高速信号的滤波，利用正交调制技术和直接数 字频率合成(DDS)技术实现了基带信号的宽带、高速跳频。 2、给出了系统的实现方案及硬件平台设计，完成了器件的选择以及发射机的 电路调试。 3、完成了相关模块的 FPGA 实现，包括信息组帧、多进制扩频、多相滤波器、 数字正交调制和跳频、FPGA 与外围芯片的通信接口等模块，并对相关模块进行验 证。 4、完成了发射机的软硬件联调和功能测试，结果表明发射机的性能可以达到 设计指标。 关键词：混合扩频 RS 纠错编码 多相滤波器 FPGA 实现 Abstract Hybrid spread spectrum system that consists of direct sequence spread spectrum, M-ary spread spectrum and frequency hopping can achieve strong resistance to interception and interference. This thesis completes scheme and hardware platform design of the low-interception hybrid spread spectrum transmitter, as well as FPGA implementation of related modules. The main contents are as follows: Principle of hybrid spread spectrum system is introduced in detail; simulation of the M-ary spread spectrum system with RS error-correction coding is given. The realization of high-speed signal filtering using polyphase filter technique is presented. Approach to realization of broadband, high-speed baseband frequency hopping based on orthogonal modulation technique and direct digital frequency synthesis (DDS) technique is proposed. The thesis presents implementation scheme and hardware platform design of the whole system. Relevant devices are selected carefully and circuitry debugging is completed. Related modules are implemented by FPGA, including data framing, M-ary spread spectrum, polyphase filter, digital orthogonal modulation, frequency hopping and communication interface between FPGA and peripheral chips. Verification of proposed modules is carried out. The thesis completes joint debugging of software and hardware, as well as function testing of the transmitter, the results show that the performance of transmitter can reach the design targets. Keywords: Hybrid spread spectrum RS error-correction coding Polyphase filter FPGA implementation 目录 HYPERLINK \l _bookmark0 第一章