Antenna Concepts and Technologies for Future 5G
Satellites
引言引言
数字化是进一步经济增长的关键。但是,如果有合适的电信基础架构,那么数字化只能提供所需的改进。5G将提供此基础
架构。 公开讨论主要是由诸如传感器和大数据,工业4.0,自动驾驶,智能轨道等想法推动的。当然,工件与铣床之间的通信
不需要卫星。同样,对于自动驾驶或对时延要求苛刻的其他应用,也不能使用对地静止卫星。但是,将来的大部分应用程序仅
需要高数据吞吐量。 当前,约60%的移动数据量是由视频流引起的。 在接下来的5年中,预计将增加到74%[1]。 视频流是对
地静止卫星的核心业务。
其他重要方面是要克服数字鸿沟和现代工作模式的推动力。 地面基础设施的现代化将需要大量资源。因此,它将主要发生
在城市和大都市地区。 存在已经存在的数字鸿沟将增大的风险。 迁入城市将增加生活成本,而农村人口外流将导致农村地区
生活质量进一步下降。 例如在德国,许多高度创新的中小企业都位于农村地区。 他们的贡献对于经济增长至关重要。 对于农
业数字化而言,这也是未来成功的关键动力。
卫星可以补充地面电信基础设施。 在没有或没有现代地面基础设施的地区,卫星通信至少可以用于不需要低延迟的应用。
典型示例包括视频流,用于制造的数字模型交换,软件维护和更新,远程教学和社交网络。 视当地情况而定,在地面基础设
施可用之前,卫星通信可以是一种桥接技术,也可以是地面解决方案过于昂贵的地区的永久解决方案。 该卫星将用于5G网络
的回程。 不管回程是通过有线,地面无线还是通过卫星实现,用户侧都是相同的
II. requirements and concepts for future high throughput satellites
A. Antenna scenarios
High throughput satellites cover the service area with small high gain spot beams. For their antennas usually the single feed
per beam (SFB) or multiple feeds per beam (MFB) principle are used [2] [3]. The feed systems are complex assemblies of
waveguide components manufactured by milling, turning, spark erosion or other traditional technologies [4]
高通量卫星以小的高增益点波束覆盖了服务区域。 对于它们的天线,通常使用单波束每馈电(SFB)或多波束每波束
(MFB)的原理[2] [3]。 馈送系统是通过铣削,车削,电火花腐蚀或其他传统技术制造的波导组件的复杂组件[4]
Key parameter for satellite providers are the costs per bit. Eutelsat-KaSat, one of the currently largest satellites serving
Europe, has a capacity of about 90 Gbps, spread over 82 beams [2]. Such satellites inclusive launch and ground segment
needn typical Capex of 300-500 Me. Target value for the cost of future high throughput satellites are 1 Me/Gbps and below
[5]. This means a massive cost reduction is required or a significant increase of capacity without additional costs.
卫星提供商的关键参数是每比特成本。 Eutelsat-KaSat是目前服务于欧洲的最大卫星之一,容量约90 Gbps,分布在82束波束
上[2]。 包括发射和地面部分在内的此类卫星通常需要300-500 Me的资本支出。 未来高吞吐量卫星成本的目标值为1 Me /
Gbps或更低[5]。 这意味着需要大量降低成本,或显着增加容量而无需额外成本。
A promising way to increase capacity significantly, is a higher frequency re-use factor. This can be achieved, if the same
coverage is served by more but smaller beams. If the beam diameter is reduced by a factor of 2, the area is reduced by a
factor of 4 and so frequency re-use factor and capacity increase by a factor of 4. This increase is achieved without an
increase of RF power. This means there are no additional costs for power amplifiers or thermal hardware.
显着提高容量的一种有前途的方式是更高的频率复用系数。如果相同的覆盖范围由更多但更小的波束提供服务,则可以实现此
目的。如果将光束直径减小2倍,则将面积减小4倍,因此频率重用因子和容量增加4倍。在不增加RF功率的情况下实现了这种
增加。这意味着功率放大器或热硬件没有额外的成本。
Larger reflectors enable smaller beams, but the number of beams and so the number of feeds has to be increased. As the
available space for the accommodation of the feed clusters does not increase, the feeds have to become smaller. For the
same reason also a lower mass is required. Our heritage polariser for single feed per beam antennas was designed for a
beam spacing of 60 mm and has a mass of 300 g [6]. In order to increase the number of feed by a factor of 4 without an
increase of required room or mass, a new small and lightweight polariser has been developed in the frame of the Artes C&G
programme Ka-band User Feed (KaUF). The new polariser (Fig. 1) enables a horn spacing of 30 mm and has a mass of
only 70 g. Compared to our heritage polariser four times more polarisers can be accommodated without an increase of total
mass or space. Further savings are possible by the use of waveguide panels instead of single waveguide runs. Within a
panel, waveguides can share side walls. Additionally to the distribution of the RF power, the waveguide panel can also be
used as structural support for the feed systems.