Broadband Digital Doherty Amplifiers for Sub-6 GHz 5G wireless Applications

功率放大器（PA）是无线通信基站中最大的能源消耗者，其消耗的能量约占基站总能量的65%。因此，寻找新的解决方案来提高射频发射机系统的效率一直是射频发射机系统设计中的一个重要课题。在提高效率的技术中，Doherty PA （DPA）以其良好的性能和简单的结构在商用基站应用中得到了广泛的应用。但是，传统的DPA带宽较窄，不适合5G等宽带通信标准。为了克服窄带宽问题，卡尔加里大学无线电实验室的Darraji和Ghannouchi提出了数字多尔蒂功率放大器（DDPA）架构。发表的结果表明，与传统模拟DPA相比，在满足4G标准的同时，更宽带宽下的功率效率有了实质性的提高。此次由三星AI中心（加拿大）赞助的合作研究计划与卡尔加里大学无线电实验室正在进行的研究活动是一致的。本研究计划的目标是开发用于sub- 6ghz 5G通信的DDPA，以提高无线发射机的性能并降低系统运行能量成本。本方案以400MHz的更宽射频带宽为目标，解决硬件和软件两方面的内存效应问题，同时实现高效率和良好的线性度。这种数字多尔蒂功率放大器的开发对5G无线网络具有重要意义。预计三星AI中心（加拿大）将进一步投资和支持后续的研究和开发活动，以便将预期的研究成果整合并用于未来在加拿大和其他地方的基站基础设施

The power amplifier (PA) is the largest energy consumer in the base station for wireless communications, which consumes around 65% of the total energy of the base station. Therefore, the search for novel solutions to enhance the efficiency of the PA is always a critical topic in the RF transmitter system design. Among the efficiency-enhancing techniques, the Doherty PA (DPA) has been widely used in commercial base station applications due to its good performance and simple structure. However, the conventional DPA is of narrower bandwidth, which is not suitable for wideband communication standards such as 5G. To overcome the narrow bandwidth issue, Digital Doherty Power Amplifier (DDPA) architecture was proposed by Darraji and Ghannouchi at the iRadio lab of the University of Calgary. The published results demonstrated a substantial improvement of the power efficiency over wider bandwidth while meeting 4G standards in comparison with conventional analog DPA.This collaborative research proposal sponsored by Samsung AI Center (Canada) is in line with the research activities being conducted in the iRadio lab of the University of Calgary. This research proposal targets the development of DDPA for sub-6-GHz 5G communications to boost the performance of the wireless transmitter and reduce the system running energy cost. This proposal is targeting a wider RF bandwidth of 400MHz and solving the memory effects issue at both hardwire and software sides to achieve high efficiency and good linearity at the same time.The development of such Digital Doherty Power Amplifier is of great importance to 5G wireless networks. It is anticipated that Samsung AI Center (Canada) would further invest and support follow-up research and development activities to integrate and use the expected research results for their future base station infrastructure in Canada and elsewhere