Link self adaptation method based on self adaptation coded modulation and automatic retransmission request

A technology of automatic retransmission request and link adaptation, applied in unequal/adaptive error prevention, error detection by signal space coding, radio/induction link selection arrangement, etc. The influence of the maximum number of retransmissions on link performance, the overall performance of AMC and HARQ is not optimal, etc., to achieve the effect of improving transmission quality, improving link adaptability, and improving system transmission performance

CN1213557CInactive Publication Date: 2005-08-03HUAWEI TECH CO LTD
0 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Publication Date
2005-08-03
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

This invention discloses a link adaptive method based on adaptive code modulation and automatic retransmission request which is to select proper channel code modulation scheme and maximum retransmission times under said channel by determining downstream channel transmission conditions then to transmit the data packet to make judgement if the said data packet needs to be retransmitted according to the mentioned information after receiving confirmation of the said data packet, if so, to judge if its retransmission times surpass the allowable maximum value at the present channel condition, if so to stop the operation, or reselect proper channel code modulation scheme and the maximum retransmission times, then to continue to transmit the data packet.
Need to check novelty before this filing date? Find Prior Art

Description

Technical field:

[0001] The invention relates to downlink adaptive technology in WCDMA system, especially the link adaptive method based on adaptive coding modulation and automatic repeat request. Background technique:

[0002] In the WCDMA high-speed data packet access system, AMC (Adaptive Coding and Modulation) and HARQ (Hybrid Automatic Repeat Request) are two very important link adaptation methods, which are used to solve the problem of data packet transmission caused by the deterioration of channel conditions. error problem. If the AMC method is adopted, when the channel condition changes, the system will select the most suitable coding and modulation scheme to adapt to the condition change of the channel according to the channel condition at that time, such as adding redundant information to eliminate the transmission error of the data packet as much as possible; if using In the HARQ method, the user terminal checks the data received in each TTI (Transmission Time In...

Examples

Embodiment Construction

[0013] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0014] AMC and HARQ are the basic link adaptive technology of high-speed data packet access system, therefore, how to improve these two methods and improve the overall performance of AMC and HARQ is the key to improve the throughput of HSDPA (High Speed ​​Data Packet Access) Means, accurately select the maximum number of retransmissions of MCS and HARQ, can improve the link adaptive performance of AMC and HARQ.

[0015] In a high-speed data access system, when the retransmission method is fixed, the choice of MCS and the maximum number of retransmissions N becomes the determining factor of the link performance of the physical layer. Therefore, the dual adaptive method of MCS and the maximum number of retransmissions not only adjusts the MCS as the channel conditions change, but also adjusts the maximum number of retransmissions adaptively with the channel con...