Unformatted text preview: (3) removes all the subcarriers at once. Thus the total number of allocated subcarriers may drop much below N and leave some empty subcarriers. The algorithm uses a greedy approach in Box (5). It finds the user who has the most power drop G k when he or she is allocated one more subcarrier. This ensures the achievement of the minimum power goal of the MA approach. The function f in the G k formula is the power-rate function. This power-rate function is convex and uniformly increasing. This function is approximated as f(r) = 0.6 * r 3 and is shown in Figure 13. Figure 13. SNR vs. Transmission Rate for P e = 10-6 ...
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- Spring '09
- Monotonic function, Convex function, BABS algorithm