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4. Writing Pulse Wave Form of DVD+R
For different speed ranges, different write strategies can be used. This document specifies 2 options:
- a pulsed write strategy, where each single mark is created by a number of subsequent separated short
pulses.
- a blocked write strategy, where each single mark is created by one continuous pulse.
1) 1
st
Method : Using Pulsed Write Strategy
* 3T :
NRZI
T = 3
2Tw
T
top
dT
top
dT
le
P
b
top
top
le
P
p
Channel bits
N = 3 : only the top pulse(T ),
first pulse lead-time dT , dT
NRZI
T > 4
2Tw
Tw
T
top
T
mp
T
mp
T
lp
dT
top
dT
le
P
b
top
top
le
lp
mp
P
p
Channel bits
N > 4 : the top pulse (T ), multi-pulse (T ) and last pulse (T ),
first pulse lead-time dT , dT
Pp : Actual write power
Pb : Bias Power
* > 4T :