Multilayer substrate

A multilayer substrate comprising:

• a multilayer body;
• a radiation conductor layer;
• one or more first ground conductor layers;
• a signal conductor layer;
• a first branch conductor layer;
• and
• a second branch conductor layer, wherein
• the multilayer body has a structure in which a plurality of insulator layers are laminated along a Z-axis,
• the radiation conductor layer is provided at the multilayer body,
• the one or more first ground conductor layers are provided at the multilayer body, overlap the radiation conductor layer assuming viewed in a negative direction of the Z-axis, and are located on a negative side of the Z-axis relative to the radiation conductor layer,
• the signal conductor layer is provided at the multilayer body, overlaps the radiation conductor layer and the one or more first ground conductor layers assuming viewed in the negative direction of the Z-axis, is located on the negative side of the Z-axis relative to the radiation conductor layer and the one or more first ground conductor layers, and is not electrically connected to the radiation conductor layer,
• a ground conductor layer non-forming region in which the one or more first ground conductor layers are not provided is present in a radiation conductor layer region in which the radiation conductor layer is provided assuming viewed in the negative direction of the Z-axis,
• the signal conductor layer includes an overlapping portion overlapping the ground conductor layer non-forming region assuming viewed in the negative direction of the Z-axis,
• in the ground conductor layer non-forming region, a conductor entirely covering the ground conductor layer non-forming region is not present on a positive side of the Z-axis relative to the signal conductor layer, except for the radiation conductor layer,
• the first branch conductor layer and the second branch conductor layer are provided at the multilayer body and are electrically connected to the signal conductor layer,
• assuming viewed in the negative direction of the Z-axis, a virtual line that passes through the overlapping portion and at which the first branch conductor layer and the second branch conductor layer are line-symmetrical to each other is present, and
• the connection point between the first branch conductor layer and the second branch conductor layer, assuming viewed in the negative direction of the Z-axis, does not overlap with the ground conductor layer non-forming region.