Multiple Beam Effects As the number of beams is increased, there is a very small decrease in overall rectenna efficiency. The efficiency curves in Fig. 7 indicate a 0.1% decrease when the number of beams is increased; however, as the number of rectennas is increased, the power per rectenna decreases since the transmit antenna is operating at its thermal limit. The cost of electricity increases as the expense of additional rectennas are included in the total system costs. The main problem with additional beams is thermal limitations in the antennas. It is expected that the waste heat rejection systems for removing heat due to d.c. to RF conversion losses in the power tubes can be designed to accommodate sufficient power for approximately four beams.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==