TOAD-Based Frequency-Encoded All Optical …
183
T 1 forces the data signal of frequency υ 2 transmitted through the port 1 of the TOAD
T 1 and output of the TOAD T 1 is υ 2 and B, a signal at υ 2, there is no signal goes
to TOAD T 3 , hence the data signal of frequency υ 2 comes out of the port 2 of the
TOAD making final output of the gate is at frequency υ 2 , i.e., ‘HIGH’ (Fig. 4).
Case (3): Similarly, when A is at frequency υ 2, the signal through the υ 2 pass
filter makes the control input of the TOAD T 2 is υ 2. In this condition, the control
signal of the TOAD T 2 forces the data signal of frequency υ 1 transmitted through
the port 1 of the TOAD T 2 and output of the TOAD T 2 is υ 1 and input B is at υ 1,
the small portion of signals through the υ 1 pass filter makes the control input of the
TOAD T 3 is υ 1 and other portion of the signal divided at the beam splitter makes
output of TOAD T 3 is signal of frequency υ 1. At this condition, all signal are absent
at port 2 in TOAD T 3 . Thus, the output of the TOAD T 3 is at frequency υ 1 .
Case (4): When A is at frequency υ 2, the signal through the υ 2 pass filter makes
the control input of the TOAD T 2 is υ 2. In this condition, the control signal of the
TOAD T 2 forces the data signal of frequency υ 1 transmitted through the port 1 of
the TOAD T 2 and output of the TOAD T 2 is υ 1, the small portion of signals through
the υ 1 pass filter makes the control input of the TOAD T 3 is υ 1 and other portion
of the signal divided at beam splitter makes the output of the TOAD T 3 is signal of
frequency υ 1 and input B is at υ 2 , and the final output is at frequency υ 1 , i.e., ‘LOW’
(Table 2).
td
SOA
∆X
υ2
Dccw
Dcw
Filter
υ1 pass
passFilter
∆X
A
td
Control
SOA
Data Signal
υ2
Dccw
Dcw
Filter
td
Control
SOA
∆X
Data Signal υ1
Dccw
Dcw
Filter
Filter
υ1 pass filter
υ2 pass filter
B
Borrow
Fig. 4 Frequency-encoded BORROW generation
183
T 1 forces the data signal of frequency υ 2 transmitted through the port 1 of the TOAD
T 1 and output of the TOAD T 1 is υ 2 and B, a signal at υ 2, there is no signal goes
to TOAD T 3 , hence the data signal of frequency υ 2 comes out of the port 2 of the
TOAD making final output of the gate is at frequency υ 2 , i.e., ‘HIGH’ (Fig. 4).
Case (3): Similarly, when A is at frequency υ 2, the signal through the υ 2 pass
filter makes the control input of the TOAD T 2 is υ 2. In this condition, the control
signal of the TOAD T 2 forces the data signal of frequency υ 1 transmitted through
the port 1 of the TOAD T 2 and output of the TOAD T 2 is υ 1 and input B is at υ 1,
the small portion of signals through the υ 1 pass filter makes the control input of the
TOAD T 3 is υ 1 and other portion of the signal divided at the beam splitter makes
output of TOAD T 3 is signal of frequency υ 1. At this condition, all signal are absent
at port 2 in TOAD T 3 . Thus, the output of the TOAD T 3 is at frequency υ 1 .
Case (4): When A is at frequency υ 2, the signal through the υ 2 pass filter makes
the control input of the TOAD T 2 is υ 2. In this condition, the control signal of the
TOAD T 2 forces the data signal of frequency υ 1 transmitted through the port 1 of
the TOAD T 2 and output of the TOAD T 2 is υ 1, the small portion of signals through
the υ 1 pass filter makes the control input of the TOAD T 3 is υ 1 and other portion
of the signal divided at beam splitter makes the output of the TOAD T 3 is signal of
frequency υ 1 and input B is at υ 2 , and the final output is at frequency υ 1 , i.e., ‘LOW’
(Table 2).
td
SOA
∆X
υ2
Dccw
Dcw
Filter
υ1 pass
passFilter
∆X
A
td
Control
SOA
Data Signal
υ2
Dccw
Dcw
Filter
td
Control
SOA
∆X
Data Signal υ1
Dccw
Dcw
Filter
Filter
υ1 pass filter
υ2 pass filter
B
Borrow
Fig. 4 Frequency-encoded BORROW generation