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Sub-carrier activation and deactivation for reducing PAPR

A technology for deactivating and reserving sub-carriers, which is used in modulation carrier systems, link quality-based transmission modification, and digital transmission systems.

Inactive Publication Date: 2009-09-16
TELEFON AB LM ERICSSON (PUBL)
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This approach doesn't bring any flexibility to the network as it needs to use the same schema

Method used

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  • Sub-carrier activation and deactivation for reducing PAPR
  • Sub-carrier activation and deactivation for reducing PAPR
  • Sub-carrier activation and deactivation for reducing PAPR

Examples

Experimental program
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Embodiment Construction

[0044] The dynamic activation of reserved subcarriers according to the present invention will be described below. image 3 One embodiment of the present invention is illustrated by a flowchart illustrating a method performed by a base station. According to step 300, the base station broadcasts on the BCH information related to one or more reserved subcarrier patterns used in the cell. User equipment needs to know the pattern of reserved subcarriers in advance in order to be able to demodulate the downlink channel. Another possibility is to standardize the patterns, but since standardizing the patterns is not a very flexible approach, preferably the patterns will be sent on the BCH as suggested in step 10. A user equipment in idle mode reads the BCH channel at least after cell reselection. Thus after cell reselection, the user equipment will obtain information about the reserved subcarrier patterns used in the cell and including all possible patterns of reserved subcarriers t...

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Abstract

The present invention relates to a method for sending reserved sub-carriers to a UE for the purpose of reducing peak to average power ratio (PAPR) of the transmitted signal to ensure sufficient quality of the modulated signal to achieve high data rate, including the steps of sending the information related to dynamic activation and deactivation of reserved sub-carriers on a common channel, which is readable for all UEs in idle and in connected mode; dynamically activating the transmission of the reserved sub- carriers in a cell when high modulation quality is to be maintained; dynamically deactivating the transmission of the reserved sub-carriers in a cell when high modulation quality is not required. The invention furthermore relates to a radio base station and a UE relating to said method.

Description

technical field [0001] The present invention relates to reducing the high Peak-to-Average Power Ratio (PAPR) in OFDM-based telecommunication systems. Background technique [0002] In E-UTRAN, OFDMA technology is used for downlink transmission (refer to 3GPP TR25.814, "Physical Layer Aspects for Evolved UTRA"). OFDM waveforms typically have a high peak-to-average power ratio (PAPR) (refer to 3GPP TR 25.814, "Physical Layer Aspects for Evolved UTRA" and R4-060853, Ericsson, Reserved sub-carriers for LTE). A very high PAPR results in an inefficient radio implementation since radio frequency (RF) components (eg, power amplifiers) must be oversized to handle rarely occurring peak (or maximum) transmit power levels. Therefore, there is a need for a technique to reduce the very high peak-to-average power ratio (PAPR). [0003] In the following, various technical aspects, requirements and limitations related to high bit rate transmission in E-UTRAN systems are described. [0004]...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H04L27/26
CPCH04L1/0003H04L27/2618
Inventor 穆哈姆德·卡兹米罗伯特·巴尔德麦尔安德斯·富鲁斯卡尔克拉斯·谢尔林法尔施德·加瑟姆扎德
Owner TELEFON AB LM ERICSSON (PUBL)