Table 3: Comparison of the resources for the different algorithms using the Altera FFT for the L5, E5a, E5b, and E1 signals, considering time multiplexing.

Implementation Logic usage Memory usage Multipliers usage
(ALM) (M20K) (DSP blocks)

3-FFT solution (Figure 5(a))
 Total8760182438

5-FFT solution (Figure 6)
 Total827479238
 Difference with 3-FFT solution−486
(−5.5%)
−1032
(−56.6%)
0

Proposed 9-FFT solution (Figure 7)
 Total 8805 484 46
 Difference with 3-FFT solution+45
(+0.5%)
−1340
(−73.5%)
+8
(+21.1%)
 Difference with 5-FFT solution+531
(+6.4%)
−308
(−38.9%)
+8
(+21.1%)

Proposed 15-FFT solution
 Total864528652
 Difference with 3-FFT solution−115
(−1.3%)
−1538
(−84.3%)
+14
(+36.8%)
 Difference with 5-FFT solution+371
(+4.5%)
−506
(−63.9%)
+14
(+36.8%)