Co-optimization of FFT and FIR in a delayless acoustic echo canceller implementation

In application specific implementation of digital signal processing algorithms optimization is important for a low power solution, not only on block level but also between blocks. This paper presents a co-optimization of a fast Fourier transform and a finite impulse response filter in a silicon implementation of an acoustic echo. The optimization gain can be measured in the number of operations and memory accesses performed per second, and therefore processing power. The optimization can also be applied to other algorithms with a similar constellation of Fourier transforms and finite impulse response filters.