Method and apparatus for implementing symmetry of channel in broadband orthogonal frequency division multiplexing system

An orthogonal frequency division and symmetry technology, applied in the field of broadband OFDM systems, can solve problems such as channel symmetry that does not have uplink and downlink, and achieve the effect of achieving symmetry

Active Publication Date: 2007-05-30
SHANGHAI ULTIMATE POWER COMM TECH
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  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

[0006] What the present invention aims to solve is the problem that the TDD broadband OFDM system in the prior art does not have the channel symmetry of uplink and downlink

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  • Method and apparatus for implementing symmetry of channel in broadband orthogonal frequency division multiplexing system
  • Method and apparatus for implementing symmetry of channel in broadband orthogonal frequency division multiplexing system
  • Method and apparatus for implementing symmetry of channel in broadband orthogonal frequency division multiplexing system

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Embodiment Construction

[0040] In a wideband OFDM system, a mapping relationship between transmission information and subcarriers needs to be established before information transmission. Generally, there are two mapping methods as follows: one is localized mapping (LocalizedMapping), that is, multiple consecutive subcarriers are used; the other is distributed mapping (DistributdMapping), that is, multiple non-contiguous subcarriers are used. If the dotted line represents the subcarriers not used for this information transmission, and the solid line represents the subcarriers used for this transmission, then the subcarriers used by the localized mapping are shown in Figure 1, while the subcarriers used by the distributed mapping The subcarriers of are shown in Figure 2.

[0041] The main advantage of partial mapping is that it can take advantage of the frequency selectivity of the broadband OFDM system to select a suitable subcarrier group for information transmission. , to adapt to the channel chara...

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Abstract

This invention discloses one method to realize signal channel symmetric property based on wide band division, which comprises the following steps: communication point gets information transmission distribution molecule load wave channel estimation in receiving information; according to the values and through plug value computation point using sub load wave signal estimation value; computing signal channel estimation values for information send process.

Description

technical field [0001] The present invention relates to a broadband OFDM (Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing) system of time division duplexing, in particular to a method and a device for realizing channel symmetry in the broadband OFDM system. Background technique [0002] OFDM is a high-speed transmission technology in a wireless environment. It divides a given channel in the frequency domain into many orthogonal sub-channels, uses a sub-carrier for modulation on each sub-channel, and transforms the high-speed serial signal into Multiple parallel low-rate signals are transmitted through the above-mentioned orthogonal sub-channels. Since the sub-carriers are orthogonal to each other, the spectrum after spread spectrum modulation can overlap each other, thereby reducing the mutual interference between the sub-carriers and improving the utilization rate of the spectrum. [0003] The traditional TDD (Time Division Duplex) sy...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H04L25/03H04L25/02H04L27/26
Inventor 索士强王映民
Owner SHANGHAI ULTIMATE POWER COMM TECH
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