Abstract: A system for detecting the depth of an antenna embedded in the card body of a smart card includes a milling device for forming a cavity in the card body, a test device disposed in close proximity to the card body, a vector network analyzer (VNA) for measuring a linear characteristic of the test device, and a control device for regulating operation of the milling device in view of data collected by the VNA. In use, the VNA generates a test signal and measures the degree of signal reflection from the test device. Under normal conditions, the VNA observes a spike in forward return loss at the natural resonant frequency of the open antenna circuit. However, at the instant that the milling device contacts the antenna, a notable variance in the degree of signal reflection is observed which indicates that the proper antenna depth has been reached.

Abstract: An integrated circuit (IC) module for a dual-interface smart card includes a planar, non-conductive module tape that is plated on its top surface to define a plurality of conductive contact pads. An IC chip is mounted on the bottom surface of the module tape and is electrically connected to each of the contact pads by a wire, the underside of each contact pad being exposed for bonding with the wire by punching a hole through the tape. The IC chip and wires are protected by an encapsulant. A pair of the contact pads, which are not required to transmit signals through direct contact, is designated as antenna contact pads. Accordingly, a hole is punched through the module tape in alignment with each antenna contact pad outside the region of the encapsulant, thereby rendering the underside of the antenna pads available for connection to an antenna by a conductive element.