WCDMA系統之手機協助/通道預測型功率控制機制

Abstract

在本論文中，提出了一種手機協助/通道預測型功率控制的機制。它由兩種方法所組成。在基地台端，使用了一種通道預測型功率控制方式，和其他傳統預測型功率控制機制比較起來，它能夠比較準確的預測訊號雜訊比。在手機端，使用了一種手機協助的功率控制方法。除了根據收到的功率控制指令以外，又參考通道增益的斜率才調整傳送訊號功率，所以這個方法不但能消除錯誤的功率控制指令的影響，又能減輕預測誤差的影響。模擬結果展現了手機協助/通道預測型功率控制機制有最低的錯誤機率。在容易發生錯誤的情況下，手機協助/通道預測型功率控制機制一比訊號雜訊比預測型以及鏈路增益預測型功率控制機制還多出了52.9%和116.6%的系統使用人數。而手機協助/通道預測型功率控制機制二比訊號雜訊比預測型以及鏈路增益預測型功率控制機制還多出了70.5%和141.6%的系統使用人數

The thesis proposes a mobile-assisted and channel-fading-prediction-based (MA-CFP) power control (PC) scheme for WCDMA systems with error-prone channels. There are two PC methods used in the MA-CFP PC scheme. The first one, which is used at the base station, is channel-fading-prediction-based PC method and it can reduce the prediction error. The second one, which is applied at the mobile-station, is the mobile-assisted PC method and it can mitigate the effect of the PC command error due to noisy channel, and prediction error. Simulation results show that the MA-CFP PC scheme 1 can achieves lower outage probability and higher system capacity than conventional link-gain and SIR prediction-based PC schemes by an amount of 52.9% and 116.6%, respectively. The MA-CFP PC scheme 2 can further increase the system capacity by the amount of 70.5% and 141.6% than link-gain and SIR prediction-based PC scheme, respectively, in error-prone channel.