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COMMON: fix ssb_offset_point_a calculation

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Even though the NR ARFCN uses a 15 kHz raster until 24250 MHz,
the ssb_offset_point_a is still scaled by 60 kHz for FR2.

So we need two different scaling factors.
This commit is contained in:
Thomas Schlichter
2026-03-09 11:50:30 +01:00
committed by Raghavendra Dinavahi
parent 1f3faac18f
commit f6c04c2672
1 changed files with 3 additions and 2 deletions
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common/utils/nr/nr_common.c
+3 -2
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@@ -1043,9 +1043,10 @@ uint32_t get_ssb_offset_to_pointA(uint32_t absoluteFrequencySSB,
const int scaling = (absoluteFrequencyPointA >= 2016667) ? 1 << (ssbSubcarrierSpacing - 2) : 1 << ssbSubcarrierSpacing;
const int scaled_abs_diff = absolute_diff / (scaling_5khz * scaling);
// absoluteFrequencySSB is the central frequency of SSB which is made by 20RBs in total
const int ssb_offset_point_a = ((scaled_abs_diff / 12) - 10) * scaling;
const int ssb_offset_scaling = (frequency_range == FR2) ? 1 << (ssbSubcarrierSpacing - 2) : 1 << ssbSubcarrierSpacing;
const int ssb_offset_point_a = ((scaled_abs_diff / 12) - 10) * ssb_offset_scaling;
// Offset to point A needs to be divisible by scaling
AssertFatal(ssb_offset_point_a % scaling == 0, "PRB offset %d not valid for scs %d\n", ssb_offset_point_a, ssbSubcarrierSpacing);
AssertFatal(ssb_offset_point_a % ssb_offset_scaling == 0, "PRB offset %d not valid for scs %d\n", ssb_offset_point_a, ssbSubcarrierSpacing);
AssertFatal(ssb_offset_point_a >= 0, "ssb offset is negative %d for scs %d\n", ssb_offset_point_a, ssbSubcarrierSpacing);
return ssb_offset_point_a;
}