Method and device for reporting channel quality indicator cqi

Abstract

The invention discloses a method and device for reporting a CQI (channel quality index). The method comprises the steps: determining the reporting of the CQI to a base station according to the power request adjustment volume in a first time period and signal-to-noise ratio change volume of a pilot channel, wherein the power request adjustment volume in the first time period is the sum of the adjustment volume of transmitting power, requested by the base station, of user equipment (UE) in the first time period; reporting the CQI to the base station. The method and device can enable the UE to report the CQI according to the actual dynamic condition of the pilot channel, can prevent redundant expenditure caused by a shorter CQI reporting period, and also can enable the base station to keep more accurate CQI prediction, thereby saving system resources, improving the accuracy of CQI prediction of the base station, and improving the system performance and user experience.

Description

technical field [0001] Embodiments of the present invention relate to the communication field, and more specifically, relate to a method and device for reporting a channel quality indicator (CQI). Background technique [0002] The user equipment (User Equipment, referred to as "UE") determines the channel quality indicator (Channel Quality Indicator, referred to as "CQI") based on the value of the signal-to-interference ratio (Signal-to-Interference Ratio, referred to as "SIR") of the downlink signal, And periodically report the CQI to the base station to indicate the channel quality received by the UE, so that the base station can perform scheduling according to the channel quality. The CQI reporting period can be configured. A smaller CQI period can enable the base station to obtain the channel quality information of the UE in a timely manner, but it will generate a larger uplink signaling load; increasing the period can reduce the uplink signaling load. However, it will ...

AI Technical Summary

Problems solved by technology

However, the above-mentioned existing technologies have the following defects: First, in some cases, there may be differences between the change of the transmission power of the DPCCH and the actual change of the CQI. For example, the base station has adjusted the transmission power of the DPCCH to the upper or lower limit of the transmission power, even if the UE If the channel status changes and the UE sends a TPC command to the base station, the power of the base station to send the DPCCH to the UE will not change. If the CQI is estimated, there will be a large error with the actual CQI; secondly, different UEs may use different noise-related parameter values ​​when determining the SIR and CQI of the DPCCH, for example, the noise power spectral density N 0 , the resulting power spectral density Nt after removing the orthogonalized interference, etc. In this way, the change of the transmit power of the DPCCH may not accurately reflect the change of the CQI, and the base station does not consider this factor, so the CQI compensation coefficient determined by the base station Inaccurate, making the CQI preset by the base station based on the CQI compensation coefficient less accurate

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