How is it calculated? Two different numbers are quoted in different material (10,94 kHz or 11,16071429 kHz). The acronym SOFDMA is not mentioned in
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I don't see any relevant discussion there.WiMAX 802.16e Scalable OFDMA (SOFDMA) subcarrier frequency?
Jan 09, 2008
1 Replies
OK, I figured it out. This was pretty tricky!
It all depends on the samplinjg factor. The e standard above says that for OFDMA sampling factor n and "for channel bandwidths that are a multiple of 1.75 MHz then n = 8/7 else for channel bandwidths that are a multiple of any of 1.25, 1.5, 2 or 2.75 MHz then n = 28/25 else for channel bandwidths not otherwise specified then n = 8/7"
The bandwidths that should be used are not specified there, but in
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Combining these two documents: sampling factor 28/25 is used for bandwidth in MHz and subcarrier number combinations of 1,25/128,
5/512, 10/1024 and 20/2048. So for all these (for example (28/25)*10*10MHz / 1024)) we have 10,9375 KHz as the subcarrier spacing.
Now the other subcarrier spacing mentioned (11,16071429 kHZ actully) would result when calculating (8/7)*10*10MHz / 1024). But it should not be used for these bandwidths. So I wonder, if there are any SOFDMA implementations using sampling of 8/7?
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