B. Simulation setup
The simulated structure employs a 3-layer board where all
the layers are RT/duroid 6002 which has a relative permittivity
of 2.94 and the thicknesses are 5-10-10 mils from top to
bottom. Total thickness of antenna substrate has been a
compromise between the large bandwidth and high radiation
efficiency requirement. To take every effect into account the
bonding films between the layers, the IC output pads, the wire
bonds, the silicon substrate and the thermal epoxy under the
chip are all included in the simulation.
The amplifiers are designed to give maximum power when
they see differential 100 ohm at the reference plane right before
the output pads so the antennas are designed accordingly. The
signal from the chips to the antennas is transmitted through
wire bonds and the ground connection is provided by the wire
bonds and thru-hole vias on the PCB. The grooves on the
antenna have an effect on both matching and resonance
frequency.