scale in DFT16 as per normal scaling sqrt(16) = 4

openair1/PHY/TOOLS/oai_dfts.c

@@ -1268,17 +1268,16 @@ __attribute__((always_inline)) static inline void dft16_simd256(int16_t *x, int1
 
   x02t    = simde_mm256_adds_epi16(xtmp0,xtmp2);
   x13t    = simde_mm256_adds_epi16(xtmp1,xtmp3);
-  ytmp0   = simde_mm256_adds_epi16(x02t,x13t);
-  ytmp2   = simde_mm256_subs_epi16(x02t,x13t);
+  ytmp0 = simde_mm256_srai_epi16(simde_mm256_adds_epi16(x02t, x13t), 2);
+  ytmp2 = simde_mm256_srai_epi16(simde_mm256_subs_epi16(x02t, x13t), 2);
   x1_flip = simde_mm256_sign_epi16(xtmp1, *(simde__m256i *)conjugatedft);
   x1_flip = simde_mm256_shuffle_epi8(x1_flip,complex_shuffle);
   x3_flip = simde_mm256_sign_epi16(xtmp3, *(simde__m256i *)conjugatedft);
   x3_flip = simde_mm256_shuffle_epi8(x3_flip,complex_shuffle);
   x02t    = simde_mm256_subs_epi16(xtmp0,xtmp2);
   x13t    = simde_mm256_subs_epi16(x1_flip,x3_flip);
-  ytmp1   = simde_mm256_adds_epi16(x02t,x13t);  // x0 + x1f - x2 - x3f
-  ytmp3   = simde_mm256_subs_epi16(x02t,x13t);  // x0 - x1f - x2 + x3f
- 
+  ytmp1 = simde_mm256_srai_epi16(simde_mm256_adds_epi16(x02t, x13t), 2); // x0 + x1f - x2 - x3f
+  ytmp3 = simde_mm256_srai_epi16(simde_mm256_subs_epi16(x02t, x13t), 2); // x0 - x1f - x2 + x3f
 
   // [y0  y1  y2  y3  y16 y17 y18 y19]
   // [y4  y5  y6  y7  y20 y21 y22 y23]
@@ -1652,14 +1651,14 @@ void dft64(int16_t *x,int16_t *y,unsigned char scale)
 
 
   if (scale>0) {
-    y256[0]  = shiftright_int16_simd256(y256[0],3);
-    y256[1]  = shiftright_int16_simd256(y256[1],3);
-    y256[2]  = shiftright_int16_simd256(y256[2],3);
-    y256[3]  = shiftright_int16_simd256(y256[3],3);
-    y256[4]  = shiftright_int16_simd256(y256[4],3);
-    y256[5]  = shiftright_int16_simd256(y256[5],3);
-    y256[6]  = shiftright_int16_simd256(y256[6],3);
-    y256[7]  = shiftright_int16_simd256(y256[7],3);
+    y256[0] = shiftright_int16_simd256(y256[0], 1);
+    y256[1] = shiftright_int16_simd256(y256[1], 1);
+    y256[2] = shiftright_int16_simd256(y256[2], 1);
+    y256[3] = shiftright_int16_simd256(y256[3], 1);
+    y256[4] = shiftright_int16_simd256(y256[4], 1);
+    y256[5] = shiftright_int16_simd256(y256[5], 1);
+    y256[6] = shiftright_int16_simd256(y256[6], 1);
+    y256[7] = shiftright_int16_simd256(y256[7], 1);
   }
 
   simde_mm_empty();