Granted Patent B2

US 12,425,105 · App. 18/043,925 · Granted Sep 23, 2025

Inventors: Yasuhiko Nakanishi (Musashino, JP); Shigeru Kanazawa (Musashino, JP); Toshihide Yoshimatsu (Musashino, JP); Atsushi Kanda (Musashino, JP)

Assignee: Nippon Telegraph and Telephone Corporation

H04B10/508H04B10/505

Abstract

Claims (85)

1. An optical burst transmitter including a control circuit configured to output a data signal and a burst control signal and a semiconductor optical amplifier configured to output an optical data signal modulated using the data signal as an optical burst data signal controlled using the burst control signal, the optical burst transmitter comprising:

an electric line configured to connect the control circuit and the semiconductor optical amplifier and transmit the burst control signal; and

an impedance matching circuit configured to impedance-match a characteristic impedance of the electric line and the semiconductor optical amplifier with each other,

wherein the impedance matching circuit has a resistance value of Z0 in parallel with the semiconductor optical amplifier when a characteristic impedance of the electric line is Z0.

2. The optical burst transmitter according to claim 1 , wherein the impedance matching circuit has a resistance value of Z0-Rf in series with the semiconductor optical amplifier when a resistance value in a forward direction of the semiconductor optical amplifier is Rf and a characteristic impedance of the electric line is Z0.

3. The optical burst transmitter according to claim 1 , wherein the impedance matching circuit includes a first resistor having a resistance value of RP1 in parallel with the semiconductor optical amplifier and a second resistor having a resistance value of RS1 in series with the semiconductor optical amplifier and is set so that

Math

.

1

RP

⁢

1

×

RS

⁢

1

+

Rf

RS

⁢

1

+

RP

⁢

1

+

Rf

=

Z

⁢

0

is satisfied when a resistance value in a forward direction of the semiconductor optical amplifier is Rf and a characteristic impedance of the electric line is Z0.

4. The optical burst transmitter according to claim 1 , wherein the impedance matching circuit includes a first resistor having a resistance value of RP1 in parallel with the semiconductor optical amplifier and a second resistor having a resistance value of RS1 in series with the semiconductor optical amplifier and is set so that RP1=Z0 is satisfied when a resistance value in a forward direction of the semiconductor optical amplifier is Rf and a characteristic impedance of the electric line is Z0.

5. The optical burst transmitter according to claim 1 , wherein the impedance matching circuit includes a first resistor having a resistance value of RP2 in parallel with the semiconductor optical amplifier and a second resistor having a resistance value of RS2 in series with the parallel circuit composed of the semiconductor optical amplifier and the first resistor and is set so that

Math

.

2

0.82

×

Z

⁢

0

<

Rf

×

RP

⁢

2

Rf

+

RP

⁢

2

+

RS

⁢

2

<

1.22

×

Z

⁢

0

0.82

×

Z

⁢

0

<

RS

⁢

2

+

RP

⁢

2

<

1.22

×

Z

⁢

0

is satisfied when a resistance value in a forward direction of the semiconductor optical amplifier is Rf and a characteristic impedance of the electric line is Z0.

6. The optical burst transmitter according to claim 1 , wherein the impedance matching circuit includes a diode inserted in a reverse direction in parallel with the semiconductor optical amplifier and a resistor having a resistance value of Z0-Rf in series with the parallel circuit including the semiconductor optical amplifier and the diode, and the diode has the same resistance in forward and reverse directions as the resistance value of the semiconductor optical amplifier, when a resistance value in a forward direction of the semiconductor optical amplifier is Rf and a characteristic impedance of the electric line is Z0.

7. The optical burst transmitter according to claim 1 , wherein the impedance matching circuit includes: a first resistor having a resistance value of Z0-Rf in series with the semiconductor optical amplifier; and a series circuit composed of a diode inserted in a reverse direction in parallel with the semiconductor optical amplifier and a second resistor having a resistance value of Z0-Rf, and the diode has the same resistance in a forward direction and the reverse direction as the resistance value of the semiconductor optical amplifier, when a resistance value in a forward direction of the semiconductor optical amplifier is Rf and a characteristic impedance of the electric line is Z0.

Assignments (2)

Continuity (1)

References Cited (13)