System study and technical development on the Solar Power Satellite with concentrators and transmitters in the sandwich structure

太阳能发电卫星（SPS）是一种独特而有希望的发电站，可以满足地面不断增长的能源需求，而不会破坏我们的地球母亲的环境。然而，由于美国能源部/美国宇航局设计的参考系统过于庞大和昂贵，因此必须在SPS上进行新的突破。我们已经提出了一个新的概念的SPS，它包括一个发生器/发射器的三明治结构和大型收集器。我们正在研制一种新型的高功率微波发射机，它具有夹层结构的反向天线，以实现我们的SPS新概念。对新型微波发射机进行了如下改进：1）提高发射频率可以减小发射机体积;微波的频率为4.8 GHz，以使发射器的直径减半。2）半频（2.4GHz）的微波作为反向天线的导频信号，使RF电路非常简单和精确。发射天线直接与放大器相连，减少了电缆损耗，减轻了天线重量。使用反向天线进行精确波束控制的演示。

The Solar Power Satellite (SPS) is one of the unique and hopeful electric power stations to satisfy ever-increasing energy demand on the ground without destroying the environment of our mother planet Earth. However, new breakthroughs must be investigated on the SPS, because the reference system designed by DOE/NASA is too huge and too expensive for the realization. We have already proposed a new concept of the SPS, which consists of a generator/transmitter of a sandwich structure and large collectors. We are developing a new high power microwave transmitter with a retrodirective antenna in the sandwich structure in order to realize our new concept of the SPS. The new microwave transmitter has successfully been improved as follows :1)Higher frequency can make the transmitter smaller. The frequency of the microwave is 4.8 GHz to make the diameter of the transmitter half.2)Half frequency (2.4 GHz) of the microwaves is used as a pilot signal of the retrodirective antenna to make RF circuit very simple and accurate.4)The transmitting antenna is directly connected to the amplifiers to reduce the loss of cables and the weight of the antenna.We successfully carried out a Microwave Power Transmission demonstration using the retrodirective antenna for the accurate beam control.