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

A frequency domain channel estimation method for OFDM multiplex system

An orthogonal frequency division and frequency domain channel technology, which is applied in the field of frequency domain channel estimation and can solve the problems of sensitivity, pilot subcarrier position sensitivity, and large computational load.

Inactive Publication Date: 2008-09-17
UNIV OF ELECTRONICS SCI & TECH OF CHINA
View PDF0 Cites 59 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] Among them, the implementation complexity of method (1) is small, but the noise is not suppressed, and the performance is relatively poor
Method (2) can effectively suppress the influence of noise and interference through time-domain filtering. The algorithm has low complexity and is suitable for hardware implementation. However, the algorithm is very sensitive to the position of the pilot subcarrier, and the change of the position of the pilot subcarrier will cause Rapid deterioration of channel estimation performance
Method (3) is to solve the problem that method (2) is sensitive to the position of pilot subcarriers. First, the initial values ​​of channel estimation on all subcarriers are obtained by pre-interpolation in the frequency domain, and then noise suppression is performed by time domain filtering. The performance of this scheme It depends on the accuracy of the selected interpolation algorithm and the number of pilots, and requires a large amount of calculation, but none of these methods have studied the influence of the pilot subcarrier position offset on the accuracy of channel estimation in domain channel estimation. eliminate

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
  • A frequency domain channel estimation method for OFDM multiplex system
  • A frequency domain channel estimation method for OFDM multiplex system
  • A frequency domain channel estimation method for OFDM multiplex system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0028] The specific implementation examples of the present invention are given below. It should be noted that the parameters in the examples do not affect the generality of this patent.

[0029] 1. Transmitter and receiver

[0030] The binary information bits are digitally modulated according to figure 1 Subcarrier allocation is performed, IDFT is performed, cyclic prefix (CP) is added, and transmission is performed from the transmitter.

[0031] The receiving antenna receives the signal, completes the removal of the cyclic prefix, DFT transformation, separates the data of the pilot subcarrier and the data subcarrier, and recovers the information bits sent by the transmitter after demodulation through channel estimation and equalization.

[0032] Two, examples

[0033] Assuming an OFDM system, the total number of subcarriers is N=1024, the serial number of subcarriers is 0~1023, and the length of the cyclic prefix is ​​selected as L cp =216, the signal modulation method is Q...

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 a frequency domain channel estimation method for an orthogonal frequency division multiplexing system, characterized in that a pilot frequency sub-carrier phase is compensated at a receiving terminal. According to the invention, the effect of pilot frequency sub-carrier position offset to channel estimation accuracy is eliminated, which exists DFT interpolating estimating algorithm with noise suppression function and frequency domain channel estimating algorithm for the OFDM system, and the implementing complexity is low, making the method suitable for hardware implementation.

Description

technical field [0001] The invention belongs to the field of mobile communication, and mainly relates to frequency-domain channel estimation technology of an Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Division Multiplexing) system. Background technique [0002] Orthogonal Frequency Division Multiplexing is a special multi-carrier transmission scheme. It divides a wideband channel into a plurality of mutually orthogonal narrowband flat fading sub-channels to transmit data simultaneously, which is beneficial to overcome the frequency selective fading of wireless channels. In practical applications, OFDM system demodulation can be divided into coherent demodulation and differential demodulation. When using differential demodulation, the receiver does not need to perform channel estimation, which can simplify the complexity of the receiver, but compared with coherent demodulation, the performance of differential demodulation is 3dB worse. For cohere...

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): H04L27/26H04J11/00H04L1/00
Inventor 雷霞王晨唐万斌李少谦
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