Digital interference in monolithic integrated antennas

The development of wireless sensor systems for various applications requires miniaturization of the sensor transceivers. The antenna is among the bulkiest components. One option for reducing its size is to integrate the antenna on-chip. This can be efficiently achieved by sharing the available chip metallic structures between the digital circuitry and the antenna. In this case the source of the MOS transistors are directly connected to the antenna and their switching currents induce power at the antenna port, which can be treated as noise. This paper evaluates the resulting interference power, which is needed for the budgeting of wireless links using on-chip antennas.