Packaging for wireless communications

The key packaging problems which remain to be addressed for wireless communication adapters are: 1) packaging technologies supporting very low-profile card design, such as direct chip attach for 5-mm thick PCMCIA applications; 2) packaging for filter and discrete passive components; 3) integration of antennas into the enclosure, using printed planar antenna approaches; 4) low-cost RF packaging technology reducing the parasitic effects of single-chip packaging; and 5) techniques providing shielding between subsystems and between the sensitive transceiver and the computer system emissions. Good EMI suppression is also essential since FCC qualification has been a problem for a number of wireless PCMCIA products. In the future wireless communication adapters for the mobile PC market will use standard packaging technology for low-cost. PC board materials will be selected for low dielectric losses, but wherever possible, standard single-chip packaging will be preferred over hybrids or MCMs. There are unique aspects to wireless transceiver design, however, which require new design tools for layout, field calculations, and noise coupling analysis. Discrete components and filters are used extensively in RF designs, and they will remain the most challenging problem from a packaging perspective, with considerable opportunity for cost and size reduction