Abstract: A logarithmic type of aerial array is formed of a plurality of similar broadband active aerial elements linearly arranged with logarithmic spacings, each aerial element being connected to a frequency-sensitive filter. The filters have progressive frequency-sensitive characteristics along the array such as to tend to pass higher frequencies where the elements are more closely spaced and lower frequencies where the elements are more widely spaced. The aerial elements are preferably each in the form of a loop, the impedance around the loop being increased in a region on the opposite side of the loop from the loop termination.