Microstrip series-fed array based on the strip-slot element

A novel series array, based on the use of the broadband complementary strip-slot radiating element loading a microstrip line, is presented. The main advantage of this proposal is that, by using this broadly-matched slot radiator, the design of such a slot planar array is simplified, since it is not required to make any effort to match the structure. An array with five elements has been manufactured and measurements of the reflection response are presented. In addition, the scanning capabilities of the array are analysed by applying the spatial harmonic expansion and proven by electromagnetic simulations. The proposed structure is able to scan from backward to forward beam directions within two radiating bands (around 6.3GHz and 14.1GHz).