Optical transmitter with integrated amplifier and pre-distortion circuit

• US 20060182449A1
• Filed: 02/16/2005
• Published: 08/17/2006
• Est. Priority Date: 02/16/2005
• Status: Abandoned Application

• Current Assignee: Emcore Corporation
• Original Assignee: Emcore Corporation
• Inventors: Lu, Albert, Iannelli, John
• Application Number:
  US11/059,790
• Publication Number:
  US 20060182449A1
• Time in Patent Office: Days
• US Class Current: 398/186
• CPC Class Codes: H04B 10/58 Compensation for non-linear transmitter output

Abstract

An optical transmitter including a housing containing an electrical input disposed in said housing for receiving an information signal; an amplifier for electronically amplifying the input signal; and a laser connected to the output of the amplifier for generating a modulated light beam corresponding to the information signal that is emitted externally from said housing.

Claims

1. An optical transmitter module comprising:

a housing including an electrical input for receiving a communications signal;

an amplifier disposed in said housing connected to the electrical input for electronically amplifying the communications signal; and

a laser disposed in said housing and connected to said amplifier for generating a modulated light beam that is emitted externally from said housing corresponding to said communications signal.

2. A transmitter as defined in claim 1, wherein the laser is amplitude modulated by the electrical communications signal.

3. A transmitter as defined in claim 1, wherein the housing is hermetically sealed.

4. A transmitter as defined in claim 1, wherein the amplifier includes a bipolar transistor configured as a common collector amplifier.

5. A transmitter as defined in claim 1, wherein the amplifier includes a FET configured as a common drain amplifier.

6. A transmitter as defined in claim 1, wherein said communications signal is an analog radio frequency signal.

8. An optical transmitter module comprising:

a housing, including an electrical input for receiving a communications signal;

a pre-distortion circuit disposed in said housing connected to the electrical input for electronically modifying the communications signal; and

a laser disposed in said housing and connected to said circuit for generating a modulated light beam that is emitted externally from said housing corresponding to said communications signal.

a transmitter as defined in claim 1, wherein the laser is amplitude modulated by the electrical communications signal.

9. A transmitter as defined in claim 8, wherein the housing is hermetically sealed.

10. A transmitter as defined in claim 8, wherein said communications signal is an analog radio frequency signal.

7. A transmitter as defined in claim 7, further comprising a pre-distortion circuit connected to the amplifier and disposed in said housing.

11. An optical transmitter for converting and coupling an information-containing electrical signal with an optical fiber comprising;

a housing including an electrical input for coupling the transmitter with an external printed circuit board and for receiving an information-containing electrical communications signal, and an optical signal output adapted for coupling with an external optical fiber for transmitting an optical communications signal;

at least one semiconductor laser in the housing for converting between an information-containing electrical signal and a modulated optical signal corresponding to the electrical signal; and

a processing circuit in the housing for processing the communications signal into a modulating electrical signal;

12. An optical transmitter comprising;

a driver circuit for receiving an input information signal and for producing a modulated current output; and

a packaged laser module, including an intermediate circuit connected to the driver circuit, and a semiconductor laser connected to the intermediate circuit for producing a modulated light beam representative of the input information signal, and a temperature control element for controlling the ambient temperature of the intermediate circuit and the laser.

13. A transmitter as defined in claim 12 wherein the packaged module is hermetically sealed.

14. A transmitter as defined in claim 12 wherein the intermediate circuit is a pre-distortion circuit.

15. The optical transmitter as defined in claim 12 wherein the amplifier comprises a source follower amplifier and wherein the laser is coupled to a source of an amplifier transistor.

16. The optical transmitter as defined in claim 12 wherein the amplifier comprises a cascode amplifier and wherein the laser is coupled between a cascode transistor and a transconductance transistor.

17. The optical transmitter as defined in claim 12, wherein the amplifier comprises a common source amplifier and wherein the laser is coupled to drain of an amplifier transistor.

18. The optical transmitter as defined in claim 12, further comprising a DC blocking capacitor coupled to the first electrode of the between the amplifier and the predistorted analog input signal.

19. The optical transmitter as defined in claim 12, further comprising an inductor coupled between the laser diode and a laser bias control signal, wherein the inductor provides a DC current path to the laser diode.

20. The optical transmitter as defined in claim 12, further comprising an impedance matching resistor coupled between the first electrode of the amplifier and ground.

21. The optical transmitter as defined in claim 12, further comprising a predistortion circuit coupled to first electrode of the amplifier, wherein the predistortion circuit generates a predistortion signal that is substantially equal in magnitude and opposite in sign to inherent distortion generated by the laser diode.