Microwave power transmission system with phase and amplitude controlled magnetrons

Since the first proposal of a Space Solar Power System (SSPS) in Space in 1968, many different types of the SSPS have been proposed. The SSPS reference system, the SPS2000, the Sun Tower and Recent Japanese Models are among them. Some of them are designed with microwave power transmission (MPT) technology based on a microwave power transmitter with microwave tubes. The electronic tubes such as Klystron or magnetron have high efficiency (> 70%) and high power output (over kW). The other MPT system is a microwave power transmitter with semiconductor amplifiers. However, the efficiency of the semiconductor amplifier is still below 40% and still much more expensive compared with the microwave tubes. A power-weight-ratio of the semi-conductor amplifier is over 50g/W and heavier than that of a microwave tube (below 30g/W). The higher the efficiency, the less launching weight and size can be attained. In this paper, we show a new concept of a microwave power transition system with phase and amplitude controlled magnetrons (PACM) with high efficiency and we propose a new phased array system with PACMs for the SSPS.