Policies for fault-tolerance through mixed space- and time-redundancy in semi-systolic FFT arrays

Fault-tolerance in semisystolic FFT (fast Fourier transform) arrays is considered, with the primary aim of obtaining either end-of-production restructuring or offline reconfiguration at run-time. A mixed-mode solution is proposed, limiting the amount of structure redundancy, keeping intact nominal processing speed, more complex fault distributions require use of time-redundancy, whereby nominal speed decreases but processing power is kept unchanged. The modified architecture granting such performances is presented, and the percentage of survival to faults thus achieved is evaluated. Reliability is assessed by evaluation of the weighted probability of survival for the fault-tolerant structure related to the number of present faults.<>