基于包络脉宽和相位差分调制的低功耗数字型发送前级研究

项目名称： 基于包络脉宽和相位差分调制的低功耗数字型发送前级研究

项目编号： No.61306037

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 周波

作者单位： 北京理工大学

项目金额： 25万元

中文摘要： 便携式无线移动终端所需的发送前级在设计上要兼顾高效率和高线性度，并支持多模多帯操作，在实现该目标的众多技术中，极座标是个不错的选择。本项目基于极座标发射机的已有架构及其发展趋势，从数字型包络调制、全差分相位调制、高鲁棒性通路延时匹配等创新点入手，致力于为低功耗、低成本、高能效、高线性、多模多带发送前级提供可行的系统方案。 相位通路采用delta-sigma差分调制双通路压控振荡器，实现基频数字相位到射频恒包络相位的搬移；引入调谐增益数字预补偿技术确保调制线性度，使用亚连续、双模式校正环路维持载波频率。包络通路利用数字型脉冲宽度调制器驱动功率级反相器及LC滤波器，实现数字包络到模拟包络的转换并为开关型功放提供大电流驱动；基于简易的锁频环，通过匹配设计，确保延时模块的可配置与精准性。在包络通路引入简易的、零点可配置的高通数字补偿滤波器，鲁棒性地匹配相位和包络通路的简单传输函数以确保延时同步。

中文关键词： 极坐标发射机；双通路压控振荡器；自动载频校正；脉冲宽度调制；

英文摘要： Transmitters, applied in portable wireless terminals, need good tradeoff between high efficiency and high linearity, and support multi-mode multi-band operations simultaneously. Polar modulation is a good choice among many techniques to archive such a goal. Based on favorite innovations of digitized envelope modulation, full-differential phase modulation and path delay alignment with high robustness, this project is aimed to provide a feasible system solution to low-power, low-complexity, high-efficiency, high-linearity, multi-mode and multi-band transmitters, by studying existing polar architectures and the developing trend. Phase path employs a differential delta-sigma modulated dual-path voltage-controlled oscillator, to implement the conversion from baseband-frequency digital phase to radio-frequency constant-envelope one. Digital pre-compensation technique for tuning gain curve correction ensures modulation linearity, and a quasi-continuous dual-mode calibration loop stabilizes the carrier frequency. Envelope path uses a digital pulse-width modulator to drive a power inverter followed by an LC filter, implementing the conversion from digital envelope to analog one and enabling large-current driver capability at the power supply of the switched-mode power amplifier. By match design and consideration, a s

英文关键词： Polar Transmitter；Dual-path VCO；AFC；PWM；