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

OFDM (orthogonal frequency division multiplexing)-based WDM (wavelength division multiplexing)-PON (positive optical network) system and downlink data transmission method

A WDM-PON, downlink data technology, applied in the field of communication, can solve problems such as affecting the quality of data transmission and aggravating the FWM effect

Inactive Publication Date: 2011-11-09
UNIV OF ELECTRONICS SCI & TECH OF CHINA
View PDF3 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In uplink transmission, if you want to make the transmission distance longer, you need to increase the optical power of the fiber, but this will aggravate the FWM effect and affect the quality of data transmission

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
  • OFDM (orthogonal frequency division multiplexing)-based WDM (wavelength division multiplexing)-PON (positive optical network) system and downlink data transmission method
  • OFDM (orthogonal frequency division multiplexing)-based WDM (wavelength division multiplexing)-PON (positive optical network) system and downlink data transmission method
  • OFDM (orthogonal frequency division multiplexing)-based WDM (wavelength division multiplexing)-PON (positive optical network) system and downlink data transmission method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0051] system such as figure 1 It is the same as that shown, including N ONUs are respectively connected to the remote node, and the OLT is connected to the remote node. The remote node is an optical multiplexer / demultiplexer.

[0052] The OLT includes an optical multiplexer / demultiplexer and N groups of downlink sending modules and uplink receiving modules corresponding to the number of ONUs; each ONU unit includes N groups of downlink receiving modules and uplink sending modules.

[0053] like Figure 4 As shown, the i-th group (i=1,...,N) downlink sending module and uplink receiving module in the OLT correspond to 0NU i .

[0054] The downlink sending module includes a downlink laser, an optical modulator, and an OFDM modulator. The downlink data generates OFDM data after passing through the OFDM modulation module. The OFDM data is input to the optical modulator as a modulation signal. The laser (downlink optical laser) in the downlink transmission module of the OLT inp...

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

The invention provides an OFDM (orthogonal frequency division multiplexing)-based downlink data transmission method of a WDM (wavelength division multiplexing)-PON (passive optical network), and a system for implementing the method, wherein the method has longer transmission range and can effectively restrain an FWM (four wave mixing) effect. Each downlink sending module of an optical line terminal performs OFDM modulation on a downlink data stream, and converts generated base band OFDM signals up to an optical domain so as to form downlink optical signals; the downlink optical signals output by the downlink sending module of the optical line terminal have different wavelengths, an optical multiplexer / demultiplexer multiplexes the downlink optical signals output by each downlink sending module into one path of optical signals; and the downlink sending module keeps subcarriers at the central part of an OFDM frequency band vacant while performing the OFDM modulation. The downlink sending module keeps a central frequency band with serious FWM component vacant while performing the OFDM modulation, and the central frequency band is no longer used for carrying valid data, so that the downlink data transmission is less influenced by the FWM effect, and power for generating component of the FWM is greatly reduced.

Description

technical field [0001] The invention belongs to the technical field of communication, and in particular relates to the transmission performance of a wavelength division multiplexing passive optical network. Background technique [0002] PON (PON: Passive Optical Network, passive optical network) includes optical line terminal (OLT: Optical Line Terminal) and optical network unit (ONU: Optical Network Units). The OLT is located in the central office (CO: Central Office), and the connection between the OLT and the ONU is passive and does not need to provide any power. [0003] In passive optical networks, time division multiplexing PON (TDM-PON) and wavelength division multiplexing PON (WDM-PON) systems are common. Compared with TDM-PON, WDM-PON has more advantages in realizing long-distance and large-coverage transmission. When upgrading the PON to support more users, the insertion loss in TDM-PON increases while WDM-PON remains unchanged. Therefore, when WDM-PON upgrades ...

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): H04L27/26H04J14/02
Inventor 易兴文张洪波张静邓明亮邱昆
Owner UNIV OF ELECTRONICS SCI & TECH OF CHINA
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