A multiplying slot array

In search of a high power millimeter wave source this paper describes a novel multiplying slot array with space combining capability. This device distributes the power of a fundamental oscillator to an array of slots that are resonant at the second harmonic. The second harmonic is produced at the diode on each of the slots and is then radiated and power combined in free-space. The feasibility of adequate single element conversion efficiency and the use of high density slot elements has been successfully demonstrated. Single slot conversion loss measured for X and Ka-band models produced encouraging results. An 8-element multiplying array exhibited better than -12 dB side lobe level at 70 GHz. The simplicity of construction of such a device makes it useful at millimeter wave frequencies. The possibility of monolithic design is very feasible due to the simplicity of the structure.