Antenna/MMIC packaging techniques for commercial applications

Summary form only given. The author examined low-cost techniques that can be used to insert a MMIC (monolithic microwave integrated circuit) between a cost-effective antenna and the rest of the system. Injection molded plastic parts are cost effective. The loss of a microstrip line made on injection molded polyetherimide (PEI) is less than 1.0 dB/in through X-band. This is acceptable for many systems such as Altair where line loss can be overcome with the gain of the MMICs. Injection molded, metalized PEI housings are also compatible with automated die bonding and wire bonding techniques if the thickness of the PEI is greater than 0.025 in. Thin sections of PEI are not consistently flat enough for high yield wire bonding techniques. Motorola has developed an injection molded, metalized waveguide to microstrip transition that operates in Ku-band. With this technique, the transition between an MMIC and a low-cost waveguide antenna is nearly cost-free.<>