Journal of Electrical and Computer Engineering / 2012 / Article / Tab 2 / Research Article
Iterative Signal Processing for Mitigation of Analog-to-Digital Converter Clipping Distortion in Multiband OFDMA Receivers Table 2 Rough estimate for computational complexity of the clipping compensation per data symbol expressed with real addition and real multiplication operations.
Operation Additions Multiplications Scaling with
1
/
𝛼
1
0 2 Channel estimation (Receiver A)
1
3
𝑀
+
1
7
2
0
+
𝑀
Channel estimation (Receiver B) 14 16 Channel equalization 0 4 Soft symbol demapping
2
7
𝑀
⋅
2
𝑀
3
𝑀
⋅
2
𝑀
Turbo decoding
2
1
3
0
𝑀
𝑅
0 Apply channel estimate to symbol estimate
(
𝐻
𝑘
𝑋
𝑘
)
0 4 IFFT
(
2
𝑁
l
o
g
2
𝑁
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
(
𝑁
l
o
g
2
𝑁
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
Clipping
(
2
𝑁
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
0 Scaling with
𝛼
1
0 2 FFT
(
2
𝑁
l
o
g
2
𝑁
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
(
𝑁
l
o
g
2
𝑁
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
Calculating
𝑍
𝑘
and subtracting it from
𝑌
𝑘
4 0 Estimating
𝛼
1
(
3
𝑁
−
1
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
(
𝑁
+
7
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
Total (Receiver A)
[
(
(
5
+
4
l
o
g
2
𝑁
)
𝑁
−
1
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
+
(
2
7
⋅
2
𝑀
+
2
1
3
0
𝑅
+
1
3
)
𝑀
+
2
1
]
𝐼
[
(
(
1
+
2
l
o
g
2
𝑁
)
𝑁
+
7
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
+
(
1
+
3
⋅
2
𝑀
)
𝑀
+
3
2
]
𝐼
Total (Receiver B)
[
(
(
5
+
4
l
o
g
2
𝑁
)
𝑁
−
1
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
+
1
8
]
𝐼
+
(
2
7
⋅
2
𝑀
+
2
1
3
0
𝑅
)
𝑀
[
(
(
1
+
2
l
o
g
2
𝑁
)
𝑁
+
7
)
/
(
(
1
−
1
/
𝐿
)
𝑁
𝐴
)
+
2
8
]
𝐼
+
3
𝑀
⋅
2
𝑀
