Method for pilot frequency insertion and diversity emission of space-frequency encoding cascade cycle detention diversity

A cascading loop and space-frequency coding technology, which is applied in the field of wireless communication, can solve the problems of CDD characteristic distortion, affecting the performance of wireless communication system, and CDD performance can not be fully exerted, etc., and achieve the effect of simple and reasonable transmission structure

Inactive Publication Date: 2008-10-29
ZTE CORP
View PDF0 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This raises a question: how to insert the pilot designed for the four-antenna MIMO-OFDM system into the two data streams encoded by SFBC in the SFBC+CDD diversity mode?
The direct consequence of this is the distortion of the CDD characteristics: the second transmit antenna signal is no longer the cyclic delay of one transmit antenna signal, and the fourth transmit antenna signal is no longer the cyclic delay of the three transmit antenna signals
This will make the performance of CDD not fully utilized, thereby affecting the performance of the entire wireless communication system

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
  • Method for pilot frequency insertion and diversity emission of space-frequency encoding cascade cycle detention diversity
  • Method for pilot frequency insertion and diversity emission of space-frequency encoding cascade cycle detention diversity
  • Method for pilot frequency insertion and diversity emission of space-frequency encoding cascade cycle detention diversity

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0022] Considering the characteristics of SFBC and CDD, according to the corresponding relationship between time and frequency domains, the delay in the time domain is equivalent to the phase shift in the frequency domain, and the cyclic delay processing of signals in the time domain is equivalent to the phase shift processing in the frequency domain. Available:

[0023] ψ ( kδ ) = e - j 2 π N kδ

[0024] Among them, δ is the delay amount selected by CDD, N is the number of points of the inverse Fourier transform (IFFT), and k is the serial number of the data.

[0025] The CDD processing result on the signal can be equivalent to its influence on the channel. CDD increases the frequency selectivity of the channel, because CDD multipl...

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 discloses a pilot frequency inserting method for a space-frequency encoding cascade cyclic delay diversity, which is applied to a multi-input multi-output orthogonal frequency division multiplexing (MIMO-OFDM) system. After a data stream to be sent is encoded by an SFBC in a frequency domain, pilot frequencies are respectively inserted into each path of data stream on the basis of the number of the encoded data stream in the frequency domain. The invention further discloses a method for transmitting the diversity of the space-frequency encoding cascade cyclic delay diversity, which includes the steps that the data stream to be sent is encoded by the SFBC in the frequency domain and then pilot frequencies are respectively inserted into each path of data stream on the basis ofthe number of the encoded data stream in the frequency domain; the data stream inserted with the pilot frequencies is transformed to a time domain by Fourier transformation. After CDD is encoded, thedata is respectively sent to a transmitting antenna. The method of the invention overcomes the defect that the transmission performance of an SFBC plus CDD diversity mode is interfered due to unreasonable pilot insertion in the existing diversity transmitting method of the MIMO-OFDM system, thus improving the reliability of the whole communication system.

Description

technical field [0001] The invention relates to the field of wireless communication, in particular to a method for pilot insertion and diversity transmission in the space-frequency coding (SFBC) concatenated cyclic delay diversity (CDD) mode of an Orthogonal Frequency Division Multiplexing (OFDM) system. Background technique [0002] The next generation of wireless communication systems will provide better voice quality and faster data transfer rates. However, the time-varying multi-path transmission environment, limited bandwidth resources and users' demands on services make it very difficult to realize the above requirements. An effective method to solve these problems is to use diversity technology. SFBC+CDD is considered by the 3rd Generation Partnership Project (3GPP) as its long-term evolution plan (Long Term Evolution Plan) because it combines the characteristics of space-frequency coding and cyclic delay diversity and has no requirement for the number of antennas at ...

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
Patent Type & Authority Applications(China)
IPC IPC(8): H04B7/06H04L1/06H04L27/26H04J11/00H03M13/29
Inventor 赵琼
Owner ZTE CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products