FUNDAMENTAL OF DIGITAL MODULAFUNDAMENTAL OF DIGITAL MODULATIONTION
from 2PSK modulation to 128QAM modulationfrom 2PSK modulation to 128QAM modulation
NEC INTERNATIONAL TRAINING, LTD.NEC INTERNATIONAL TRAINING, LTD.RADIO DIVISIONRADIO DIVISIONYOKOHAMA TRAINING CENTERYOKOHAMA TRAINING CENTER
RING MODULATOR-1RING MODULATOR-1
IDEA OF 2PSK MODULATOR (0 -IDEA OF 2PSK MODULATOR (0 -π MOD)π MOD)
RINGMODULATOR
vco
MODOUTPUT
LOCALINPUT
DATAINPUT
1 0
70MHz
RING MODULATOR-2RING MODULATOR-2
+ 1
0 +
LOCALINPUT
MODOUTPUT
DATAINPUT
RING MODULATOR-2RING MODULATOR-2
+ 1 -
+
+
-
-
LOCALINPUT
MODOUTPUT
DATAINPUT
RING MODULATOR-3RING MODULATOR-3
0 +
+
LOCALINPUT
MODOUTPUT
DATAINPUT
+
RING MODULATOR-4RING MODULATOR-4
RINGMODULATOR
vco
MODOUTPUT
LOCALINPUT
DATAINPUT
1 0
70MHz
0180 (π)
[1][0]VECTOR DIAGRAM OF MODULATOR OUTPUT
4PSK MODULATOR-14PSK MODULATOR-1
0 -πMOD
0 -πMOD
φ
VCO
DATA-1
DATA-20 1 1 0
0 0 1 1
0 1 2 3
70MHz
P-ch
Q-ch
P-ch
Q-ch
(0)(1)
(0)
(1)
(0,0)
MODOUT
4PSK MODULATOR-24PSK MODULATOR-2
0 -πMOD
0 -πMOD
φ
VCO
DATA-1
DATA-20 1 1 0
0 0 1 1
0 1 2 3
70MHz
P-ch
Q-ch
P-ch
Q-ch
(0)(1)
(0)
(1)(0,1)
MODOUT
4PSK MODULATOR-34PSK MODULATOR-3
0 -πMOD
0 -πMOD
φ
VCO
DATA-1
DATA-20 1 1 0
0 0 1 1
0 1 2 3
70MHz
P-ch
Q-ch
P-ch
Q-ch
(0)(1)
(0)
(1)(1,1)
MODOUT
4PSK MODULATOR-44PSK MODULATOR-4
0 -πMOD
0 -πMOD
φ
VCO
DATA-1
DATA-20 1 1 0
0 0 1 1
0 1 2 3
70MHz
P-ch
Q-ch
P-ch
Q-ch
(0)(1)
(0)
(1)
(1,1)
MODOUT
4PSK MODULATOR-54PSK MODULATOR-5
0 -πMOD
0 -πMOD
φ
VCO
DATA-1
DATA-20 1 1 0
0 0 1 1
0 1 2 3
70MHz
P-ch
Q-ch
P-ch
Q-ch
(0)(1)
(0)
(1)
(1,0)
MODOUT
(1,1) (0,1)
(0,0)
16QAM MODULATOR16QAM MODULATOR
0 -πMOD
0 -πMOD
φ
VCO
DATA-1DATA-2
DATA-3DATA-4
0 0 0 0 - - - 1
0 0 0 0 - - - 1
0 1 2 3 - - - 16
70MHz
P-ch
Q-ch
P-ch
Q-ch
MODOUT
0 1 0 1 - - - 1
0 0 1 1 - - - 1
D/ACONV
D/ACONV
+3L
+L
-L
-3L
+3L
+L
-L
-3L
+3L
+L
-L
-3L
+3L +L -L -3L
64QAM MODULATOR64QAM MODULATOR
0 -πMOD
0 -πMOD
φ
VCO
DATA-1DATA-2DATA-3
DATA-4DATA-5DATA-6
0 0 0 0 - - - 1
0 0 0 0 - - - 1
0 1 2 3 - - - 64
70MHz
P-ch
Q-ch
P-ch
Q-ch
MODOUT
0 0 1 1 - - - 1
D/ACONV
D/ACONV
0 0 0 0 - - - 1
0 0 1 1 - - - 1
0 0 1 1 - - - 1
+3L
+L
-L
-3L
+5L
+7L
-5L-7L
+3L
+L
-L
-3L
+5L
+7L
-5L-7L
-L
-3L
-5L
-7L
+3L
+L
+5L
+7L
+7L +5L +3L +L -L -3L -5L -7L
8 levels
8 levels
128QAM MODULATOR128QAM MODULATOR(SDH/MLC)(SDH/MLC)
0 -πMOD
0 -πMOD
φ
VCO
data-1
data-2
data-3
data-4
data-5
data-6
data-7
data-8
70 MHz
P-ch
Q-ch
MODOUT
D/ACONV
D/ACONV
12 levels
19 Mb/s8 streams
24 Mb/s7 streams
SPEED & 8 -7CONV
MAPP-ING
+3L+L-L-3L
+5L+7L
-5L-7L
+11L
+9L
-11L-9L
12 levels
+3L+L-L-3L
+5L+7L
-5L-7L
+11L
+9L
-11L-9L
RFCOHINS
MLCENCOD
24 Mb/s8 streams
MODULATION TYPE DIFFERENCESMODULATION TYPE DIFFERENCES
2PSK 4PSK 8PSK
16 QAM 64 QAM
128 QAM 256 QAM
1 stream(100 Mb/s)
2 streams(50 Mb/s)
3 streams(33Mb/s)
4 streams(25Mb/s)
6 streams(16.7Mb/s)
7 streams(14.3Mb/s)
8 streams(12.5 Mb/s)
32 QAM
5 streams(20 Mb/s)
2 status 4 status 8 status
16 status 32 status 64 status
128 status 256 status
128QAM CONSTELLATION128QAM CONSTELLATION
12 LE
VE
LS
12 LEVELS
P-ch
Q-ch
MODULATION & BANDWIDTHMODULATION & BANDWIDTH
MODULATOR
128QAM64QAM16QAM8PSK4PSK2PSK
F0 +10 +20 +30 +40 +50-10-20-30-40-50 FREQUENCY (MHz)
100MB/s
supposed that100Mb/s data is carried by different levelof the modulator