Microstrip antenna device with slot-line-fed antenna arrays

A microstrip antenna device, comprising:

• a substrate having a top surface and a bottom surface,
• a two-dimensional first conductive structure and a two-dimensional second conductive structure arranged adjacent to each other on the top surface of the substrate, and
• a two-dimensional third conductive structure arranged on the bottom surface of the substrate and providing an electric ground plane,
• wherein the first conductive structure comprises a first array of antennas and a first feed network, each respective antenna in the first array of antennas being connected to the first feed network,
• wherein the second conductive structure comprises a second array of antennas and a second feed network, each respective antenna in the second array of antennas being connected to the second feed network,
• wherein a slot line is formed in the third conductive structure for feeding a signal to both the first feed network and the second feed network,
• wherein the first feed network comprises a primary feed line and a plurality of secondary feed lines, the primary feed line passing through a central region of the first array of antennas, and the secondary feed lines branching off from the primary feed line at different branch-off points, and
• wherein the second feed network comprises a primary feed line and a plurality of secondary feed lines, the primary feed line passing through a central region of the second array of antennas, and the secondary feed lines branching off from the primary feed line at different branch-off points.

A method for producing a microstrip antenna device, the method comprising:

• forming a two-dimensional first conductive structure and a two-dimensional second conductive structure adjacent to each other on a top surface of a substrate, the first conductive structure comprising a first array of antennas and a first feed network, the second conductive structure comprising a second array of antennas and a second feed network, each respective antenna in the first array of antennas being connected to the first feed network, each respective antenna in the second array of antennas being connected to the second feed network, and
• forming a two-dimensional third conductive structure on a bottom surface of the substrate in order to provide an electric ground plane, wherein forming the two-dimensional third conductive structure comprises:
• forming a conductive layer on the bottom surface of the substrate, and
• forming a slot line in the conductive layer, the slot line being suitable for feeding a signal to the first feed network and to the second feed network,
• wherein the first feed network comprises a primary feed line and a plurality of secondary feed lines, the primary feed line passing through a central region of the first array of antennas, and the secondary feed lines branching off from the primary feed line at different branch-off points, and
• wherein the second feed network comprises a primary feed line and a plurality of secondary feed lines, the primary feed line passing through a central region of the second array of antennas, and the secondary feed lines branching off from the primary feed line at different branch-off points.