Density enhancement of a neural network using FPGAs and run-time reconfiguration

Run-time reconfiguration is a way of more fully exploiting the flexbility of reconfigurable FPGAs. The run-time reconfiguration artificial neural network (RRANN) uses ran-time reconfiguration to increase the hardware density of FPGAs. The RRANN architecture also allows large amounts of parallelism to be used and is very scalable. RRANN divides the back-propagation algorithm into three sequential executed stages and configures the FPGAs to execute only one stage at a time. The FPGAs are reconfigured as part of normal execution in order to change stages. Using reconfigurability in this way increases the number of hardware neurons a single Xilinx XC3090 can implement by 500%. Performance is effected by reconfiguration overhead, but this overhead becomes insignificant in large networks. This overhead is made even more insignificant with improved configuration methods. Run-time reconfiguration is a flexible realization of the time/space trade-off. The RRANN architecture has been designed and built using commercially available hardware, and its performance has been measured