Gilbert A. Morin

Laminated waveguide as radiating element for array applications

This paper reports on the study of a new antenna as well as a five-element array prototype developed for communications in K-band and suitable for low temperature co-fired ceramic technology. The radiating element is an open waveguide realized in laminated technology. A special coaxial-to-waveguide transition has also been designed as feed port for measuring the prototypes. The element exhibits a 1 GHz bandwidth centered at 20.7 GHz and a 2.7 dBi gain. In an array configuration, mutual coupling between the elements is lower than -18 dB across the bandwidth. The simulated boresight radiation pattern of a five-element array is stable over the bandwidth and the gain reaches 9.2 dBi at 20.7 GHz. The measurements of the radiation pattern for a 20-degree scan angle, as well as the simulation, demonstrate the scanning capability of this array

Laminated waveguide as radiating element for phased array with brick architecture

This paper presents the study of a five-element array antenna prototype developed for communications in K-band. The radiating elements are radiating waveguides realised in laminated technology. The element exhibits a 1 GHz bandwidth around a 20.7 GHz centre frequency. The radiation patterns indicate a gain of 2.7 dBi. In an array configuration the input impedance of each radiating element is slightly perturbed by the proximity of the other antennas. The coupling between the elements, however, remains below −18 dB across the bandwidth. The simulated boresight radiation pattern of a five-element array is stable over the bandwidth and the gain reaches 9.2 dBi at 20.7 GHz. The scanned radiation patterns obtained by simulation show a good behaviour of this array for scan angles up to 50°.

Tunable filters with a constant bandwidth

Todays microwave systems can benefit greatly from the use of tunable filters, which have some distinct advantages over traditional microwave filters and are continuously being improved. This paper presents an approach for designing tunable filters with a minimum number of tuning elements. While the majority of published work in this area uses synchronous tuning, the proposed approach is based on non-synchronous tuning.

A novel electromagnetic bandgap groundplane design

This paper describes a novel groundplane that could be classified as a defected groundplane; however, instead of introducing holes (defects), the groundplane is grooved. A gridwork of grooves works with a dielectric layer above it to create regions of alternate high and low permittivity that form a periodic pattern, similar to designs with dielectric posts. A deep and wide bandgap can be obtained by optimizing the geometric dimensions. There is a trade-off for manufacturing since the design does not require any vias but does require machining of the groundplane.