Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

System and method for coherent detection with digital signal procession

Inactive Publication Date: 2017-02-09
ZTE (USA) INC
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

This patent is about using optical orthogonal frequency division multiplexing (O-OFDM) to transmit signals over long distances with high efficiency. It involves generating a multicarrier signal, separating it into separate subcarrier signals, modulating them with phase and QPSK modulators, and then recombining them to create a multiplexed signal that can be transmitted. The technical effect is to improve the spectral efficiency of signals transmitted over long distances.

Problems solved by technology

However, an ADC with these specifications may not be commercially available.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • System and method for coherent detection with digital signal procession
  • System and method for coherent detection with digital signal procession
  • System and method for coherent detection with digital signal procession

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0007]Aspects of the present invention employ optical orthogonal frequency division multiplexing (O-OFDM) to transmit signals realizing high-spectral efficiency over long distances.

[0008]FIG. 1 illustrates a schematic diagram of a transmitter and receiver according to aspects of the present invention. A laser 101 generates a continuous lightwave. The laser 101 may be a distributed feedback type laser diode (DFB-LD), which may have a wide line width. For a 100 Gbit / s QPSK for example, a line width smaller than 2 MHz may be used, although in embodiments line widths greater than 2 MHz may also be sufficient. Alternatively, the laser source 101 may be a tunable external laser with a narrow line width and low phase noise which may be preferred for high level modulation format signals. A multicarrier generator 102 receives the lightwave and generates a multicarrier signal. This multicarrier signal may be generated by a few different schemes, such as cascaded phase and intensity modulators...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

Methods and apparatus to realize high spectral efficiency in optical signals transmitted over long distances.

Description

FIELD OF THE INVENTION[0001]The present invention relates to communication systems, and particularly, coherent detection with digital signal processing.BACKGROUND[0002]Increasing bandwidth demand has been driving communication systems to higher capacities. Therefore, there is a strong motivation to enhance spectral efficiency to increase the total capacity. Employing optical orthogonal frequency division multiplexing (O-OFDM) modulation to transmit signals can realize high-spectral efficiency and long distance transmission. To achieve high receiver sensitivity with coherent detection based on digital signal processing, the bandwidth of the analog to digital converter (ADC) and the sample rate may be high. Usually, the ADC bandwidth may have two times of the bit rate of the signal, and the sampling rate may be four times of the bit rate. For example, if each subcarrier of the OFDM signal is 25 Gbaud Quadrature Phase Shift Keyed (QPSK), the ADC bandwidth should be 50 GHz and the sampl...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H04B10/2513H04L27/26H04B10/61H04B10/516H04J14/02H04J14/06H04B10/50H04L5/00
CPCH04B10/2513H04B10/503H04L27/2601H04L5/0007H04B10/6161H04J14/02H04J14/06H04B10/614H04B10/5161H04L27/2637H04L27/2697H04B10/548H04B10/5561H04B10/613
Inventor YU, JIANJUNLI, JIANQIANGCHIEN, HUNG-CHANGJIA, ZHENSHENG
Owner ZTE (USA) INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com