Abstract:
Power control is one of the most important mechanisms
influencing on the maximum capacity and performance of
Wideband Code Division Multiple Access (WCDMA)
systems. Power control algorithms used in Universal
Mobile Telecommunication System (UMTS) are based on
fixed step size algorithms. The algorithms adjust their
transmitted power based on Transmit Power Control
(TPC) commands. In this paper, we show that there is a
significant correlation between TPC sequences and user
mobility. We then introduce a new parameter called
Consecutive TPC Ratio (CTR), which will be varied by
user speeds. A new adaptive power control algorithm is
also proposed. This new power control algorithm uses
CTRs to adjust power control step sizes. The result shows
that the proposed algorithm outperforms fixed step power
control.
