“Exploration of FPGA Interconnect for the Design of Unconventional Antennas”, 2011-02-27 ():
The programmable interconnection resources are one aspect that distinguishes FPGAs from other devices. The abundance of these resources in modern devices almost always assures us that the most complex design can be routed. This underutilized resource can be used for other unintended purposes. One such use, explored here, is to concatenate large networks together to form pseudo-equipotential geometric shapes. These shapes can then be evaluated in terms of their ability to radiate (modulated) energy off the chip to a nearby receiver.
In this paper, an unconventional method of building such transmitters on an FPGA is proposed. Arbitrary shaped antennas are created using a unique flow involving an experimental router and binary images.
An experiment setup is used to measure the performance of the antennas created.
[Keywords: antenna design, geometric routing, embedded transceivers, hidden transmitter]
[Presumably one could evolve more efficient antenna designs, or hide them in apparently-innocuous circuit layouts, and use them them to exfiltrate data across even air gaps. But the paper does not discuss whether one could build a receiver as well.]