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Signal retransmission method for OFDM system based on HARQ technology

A signal and retransmission technology, which is applied in the field of signal retransmission based on HARQ technology, can solve the problems of large resources, large delay, and failure to improve the reliability of the sending end, so as to save time and resources, reduce the number of retransmissions, and ensure reliability effect

Inactive Publication Date: 2009-02-25
ZTE CORP
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] However, using the existing HARQ scheme, the technology provided is receiving and combining, which does not improve the reliability of the sending end in the retransmission process.
Especially in the TDD system, due to the use of time division multiplexing, the delay of multiple retransmissions is particularly large, and the resources occupied by multiple retransmissions are also relatively large. In order to reduce the number of retransmissions, only the reliability of retransmissions should be enhanced.

Method used

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  • Signal retransmission method for OFDM system based on HARQ technology
  • Signal retransmission method for OFDM system based on HARQ technology
  • Signal retransmission method for OFDM system based on HARQ technology

Examples

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Effect test

Embodiment 1

[0032] Embodiment 1, a signal retransmission method based on HARQ technology in an OFDM system, such as figure 1 shown, including the following steps:

[0033] A. The receiving end fails to decode, and sends a retransmission message (NACK) to the sending end.

[0034] This step specifically includes:

[0035] A1. At the sending end, the signal generated by the source is channel coded, interleaved, and modulated.

[0036] A2. The coded and modulated signal is first stored in the memory of the sending end, and then mapped to a time-frequency resource block. After passing through IFFT (inverse Fourier transform), it is sent to the receiving end through the antenna.

[0037] A1 and A2 are the same as the prior art.

[0038] A3, the receiving end stores the received signal superimposed with noise in the receiving end memory, and the decoder starts to decode; if the decoding is successful, then proceed according to the prior art, which is not within the scope of the present inven...

Embodiment 2

[0050] Embodiment 2 provides a process of hybrid automatic request for retransmission in an OFDM system, such as figure 2 shown, including the following steps:

[0051] Step 201: generating a signal of a TB interface;

[0052] Step 202: performing CRC (cyclic redundancy check) and channel coding modulation on the signal;

[0053] Step 203: store the coded and modulated signal in the memory of the sending end;

[0054] Step 204: Carry out subcarrier mapping, insert pilot, IFFT, add CP (cyclic prefix) to the signal;

[0055] Step 205: Send to the receiving end memory through the channel;

[0056] Step 206: The receiving end removes the CP of the signal, and performs FFT (Fourier transform) and channel estimation;

[0057] Step 207: The receiver uses a detection algorithm to detect the signal;

[0058] Step 208: The receiving end demodulates, decodes and checks the signal with CRC;

[0059] Step 209: The receiving end judges whether the CRC of the received signal is correc...

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Abstract

The invention discloses a signal retransmission method based on the hybrid automatic repeat request (HARQ) technique in an orthogonal frequency division multiplexing (OFDM) system, which belongs to the field of wireless communication systems. The method comprises the following steps: firstly a transmitting terminal receives the re-transmission information from a receiving terminal, and then the transmitting terminal increases the density or intensity of a pilot signal in a transmission-side memorizer and then retransmits the signal. The signal retransmission method increases the signal transmission quality and the retransmission reliability of the broadband wireless communication system during the retransmission process, thereby reducing the retransmission frequency of the wireless communication system and saving time resources.

Description

technical field [0001] The invention belongs to the field of wireless communication systems, and in particular relates to a signal retransmission method based on HARQ (Hybrid Automatic Repeat Request) technology in an OFDM (Orthogonal Frequency Division Multiplexing) system. Background technique [0002] With the rapid development of high-speed and reliable service requirements, HARQ technology has become one of the key technologies of the B3G mobile communication system. HARQ technology, also known as hybrid automatic repeat request, is an error control technology, which is the basis of high-speed data transmission. The purpose is to improve the transmission quality of signals and ensure the reliability of information. Correction) technology and automatic retransmission request ARQ technology. In HARQ, the sender will send data with certain redundant information, and the receiver will first perform FEC decoding. If it still cannot be demodulated correctly, the sender will b...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H04L1/18H04L1/16H04L1/00
Inventor 王文焕王衍文魏巍
Owner ZTE CORP
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