OPTICAL POWER SYSTEM FOR DIGITAL-TO-ANALOG LINK

• US 20160204878A1
• Filed: 01/13/2015
• Published: 07/14/2016
• Est. Priority Date: 01/13/2015
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Goodwill, Dominic John
• Granted Patent: US 9,490,902 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 10/25758 between a central unit and a single remote unit by means of an optical fibre
• CPC Class Codes: H04B 10/25759 Details of the reception of RF signal or the optical conversion before the optical fibre
• CPC Class Codes: H04B 10/5053 using a parallel, i.e. shunt, combination of modulators
• CPC Class Codes: H04B 10/506 Multiwavelength transmitters
• CPC Class Codes: H04B 10/516 Details of coding or modulation
• CPC Class Codes: H04J 14/02 Wavelength-division multiplex systems

Abstract

An optical power supply includes a plurality of lasers each providing an output at a respective optical wavelength and optical power and a plurality of optical splitter groups, each comprising an input associated with a respective one of the plurality of lasers and splitting the input into a plurality of outputs each having an output power approximated by

${\mathrm{Power}}_n=\frac{1}{x^n}{\mathrm{Power}}_{\mathrm{input}},$

where: x is an integer greater than 1; n is a number of the outputs of the optical splitter group and n=1 . . . m; m is a total number of outputs of the optical splitter group; Power_n is the output power of the n^th output; and Power_input is the optical power of the output of the laser received at the input of the optical splitter group.

Claims

1. An optical power supply comprising:

a plurality of lasers each providing an output at a respective optical wavelength and optical power; and

a plurality of optical splitter groups, each comprising an input associated with a respective one of the plurality of lasers and splitting the input into a plurality of outputs each having an output power approximated by;

2. The optical power supply of claim 1, wherein at least one of the plurality of optical splitter groups comprises an asymmetrically arranged tree of individual optical splitters each splitting an input into approximately equal outputs.

3. The optical power supply of claim 2, wherein each of the individual optical splitters split power of the input unequally so that an output connected to additional individual optical splitters receives additional power.

4. The optical power supply of claim 3, wherein the additional power accounts for optical power loss resulting from individual optical splitters so that the outputs of the respective optical splitter group are a binary sequence of fractional power.

5. The optical power supply of claim 1, wherein x=2.

6. The optical power supply of claim 1, wherein the respective optical wavelengths of each of the plurality of lasers are separated by a distance sufficient to prevent generation of beat frequencies when the respective optical wavelengths are combined.

7. The optical power supply of claim 1, further comprising a plurality of optical modulator groups each comprising a plurality of modulator inputs and associated modulator outputs, each of the plurality of modulator inputs of a respective optical modulator group connected to a respective output from different optical splitting groups such that, for each modulator group, data bit data_i modulates the optical input having the (w−

i)^th highest optical power of the optical modulator group where

data_i is the i^th bit in the data signal and i=0 . . . w−

1, where data_w-1 is the most significant bit; and

w is the number of bits in the data signal.

8. An optical system comprising:

an optical splitting section comprising a plurality of optical splitter groups, each comprising an input and splitting the input into a plurality of outputs each having an output power approximated by;

9. The optical system of claim 8, wherein at least one of the plurality of optical splitter groups comprises an asymmetrically arranged tree of individual optical splitters each splitting an input into approximately equal outputs.

10. The optical system of claim 9, wherein each of the individual optical splitters split power of the input unequally so that an output connected to additional individual optical splitters receives additional power.

11. The optical system of claim 10, wherein the additional power accounts for optical power loss resulting from individual optical splitters so that the outputs of the respective optical splitter group are a binary sequence of fractional power.

12. The optical system of claim 8, wherein x=2.

13. The optical system of claim 8, further comprising a plurality of lasers each providing an output at a respective optical wavelength and optical power, each of the lasers connected to the input of a respective one of the optical splitter groups.

14. The optical power supply of claim 13, wherein the respective optical wavelengths of each of the plurality of lasers are separated by a distance sufficient to prevent generation of beat frequencies when the respective optical wavelengths are combined.

15. The optical power supply of claim 8, further comprising a plurality of optical multiplexers each multiplexing a multi-wavelength signal of modulated outputs from a respective one of the optical modulation groups into a single analog optical signal.