We present the latest developments in the physical layer evolution for the transmission of Multimedia Broadcast Multicast Service (MBMS) over fifth generation (5G) cellular networks. We first provide an overview of how the MBMS physical layer has evolved during the initial releases of the Third Generation Partnership Project (3GPP) specifications and provide motivations and insights for key developments that have helped mature MBMS into a competitive broadcasting solution. We provide an overview of dedicated MBMS carriers for Multimedia Broadcast multicast service Single Frequency Network (MBSFN) transmission as well as Orthogonal Frequency Division Multiplexing (OFDM) numerologies with longer cyclic prefixes to support MBSFN transmission over large geographical areas with large distances between cooperating cell sites. Next, we describe the most recent enhancements to the MBMS physical layer, addressing advanced use cases in the recently completed release of the 3GPP specifications (Release 16). First, we describe the physical layer design for enabling MBSFN-based MBMS services for rooftop receivers with inter-site distances between cooperating cell sites as large as 125 km. In this realm, we demonstrate the need for an OFDM numerology with a 300-microsecond cyclic prefix to communicate effectively over channels with very large delay spreads. Next, we explain how support for high mobility up to 250 kmph was added to the standards by using an OFDM numerology that gracefully trades off inter-symbol interference due to large delay spreads and inter-carrier interference due to large doppler spreads to achieve better performance than existing numerologies at high speeds. Finally, we describe the enhancements that were made to the Cell Acquisition Subframe (CAS)—specifically, the introduction of larger aggregation levels for the Physical Downlink Control Channel (PDCCH) and the support of Physical Broadcast Channel (PBCH) repetitions—that significantly increase the coverage for the control and system information associated with MBMS that are carried by these subframes.

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蜂窝地面广播--从3GPP Release 9到Release 16的物理层演进

我们介绍了在第五代 (5G) 蜂窝网络上传输多媒体广播组播服务 (MBMS) 的物理层演进的最新进展。我们首先概述了 MBMS 物理层在第三代合作伙伴计划 (3GPP) 规范的初始版本期间是如何演变的，并为帮助 MBMS 成熟为具有竞争力的广播解决方案的关键发展提供动力和见解。我们概述了用于多媒体广播多播服务单频网络 (MBSFN) 传输的专用 MBMS 载波以及具有更长循环前缀的正交频分复用 (OFDM) 参数集，以支持在合作小区站点之间距离较远的大型地理区域上进行 MBSFN 传输. 下一个，我们描述了 MBMS 物理层的最新增强，解决了最近完成的 3GPP 规范（第 16 版）发布中的高级用例。首先，我们描述了物理层设计，用于为协作蜂窝站点之间的站点间距离高达 125 公里的屋顶接收器启用基于 MBSFN 的 MBMS 服务。在这个领域，我们证明了需要具有 300 微秒循环前缀的 OFDM 命理学，以便在具有非常大的延迟扩展的信道上进行有效通信。接下来，我们解释了如何通过使用 OFDM 数字学将高达 250 公里/小时的高移动性支持添加到标准中，该数字学优雅地权衡由于大延迟扩展引起的符号间干扰和由于大多普勒扩展引起的载波间干扰，以实现更好的性能比现有的数字学高速。