A multibeam antenna for satellite communication

The development of a multibeam antenna (MBA) for a multiple access data relay satellite system is discussed. The MBA is an array-type antenna having 19 elements; it transmits at 2.1 GHz and receives at 2.3 GHz. The receiving system makes use of an MBA of 19 beams, and the transmitting system uses a single-beam phased array. A printed slot array antenna is selected as the radiating element. A phase shifter with low loss, a wide band, and light weight will be used for transmitting beam control in the phased array antenna. A description is given of a beam-forming network for 19 elements and 19 beams that can greatly reduce the number of nodes by using the symmetry of the elements and beam arrangements.