longitudinal slots on substrate integrated waveguide

The proposed antenna array was fabricated and tested. The proposed antenna operates in the X-band for the frequency range around the 10 to 11 GHz with resonances at 10.4 and 10.8 GHz frequencies. The electromagnetic energy is coupled to the air through 3 × 3 slot array etched on top metallic layer. The proposed antenna array, excited in its TE 33 higher mode, incorporates a grounded coplanar-waveguide (CPW) CPW-feeding excitation mechanism. This short communication presents a substrate integrated waveguide planar cavity slotted antenna array.

Index Terms-Mutual coupling, ridged substrate integrated waveguide (RSIW), slotted SIW array antenna. Simulation results show good agreement with measurement results of the fabricated proposed antenna.

Since the array antenna is composed of collinear elements, it demonstrates a better cross polarization and isolation in comparison with conventional slot array antennas. Using this graph, the widths of the ridges and length of the slot can be revised in a way that the mutual coupling effect is taken into account. A 2-D graph is presented which contains the real and imaginary parts of the equivalent admittance of a slot based on the changes in the widths of the ridges and length of the slot. In this design, internal and external mutual coupling effects are taken into account through calculating the active admittance for each slot of the array. An eight-element longitudinal slot array antenna on the broad wall of the RSIW is designed based on Elliot's design procedure.

The admittance of a single slot in the proposed structure is obtained regarding the different values of the main parameters of the structure. Also, the asymmetric field distributions on both sides of each slot, which are required for making radiation possible, are realized through using ridges close to the narrow walls of the SIW. The slots in the proposed structure are placed on the centerline of the broad wall of the substrate integrated waveguide (SIW), in order to reduce cross polarization. A novel shunt longitudinal slot planar array antenna based on a ridged substrate integrated waveguide (RSIW) with a good cross polarization and isolation is designed and fabricated.

Longitudinal slots on substrate integrated waveguide