Method for determining down initial transmitting power

Abstract

The method comprises: considering the path losses and the time slot interference when calculating the downlink initial transmitted power in order to figure out the size of downlink initial transmitted power reasonably and to avoid the influence caused by oversized transmitted power or undersized transmitted power. During the process of just establishing the physical layer or re-allocating the channel or inter-cell switchover, even if there isn't the destination time slot interference measured value reported by UE, the invention can also figure out the downlink time slot interference, and use the downlink power control to calculate the downlink initial transmitted power so as either to ensure the success ratio of access and the Quos requirement or to avoid the heavy interference to other UEs.

Description

technical field [0001] The present invention relates to a communication system, in particular to a method for determining downlink initial transmission power. Background technique [0002] Code Division Multiple Access (CDMA) is a modulation and multiple access technology based on spread spectrum communication. In a CDMA communication system, since the base station and the mobile station use the same wireless frequency band, the base station will transmit signals to a certain mobile station. Cause interference to mobile stations in this cell and neighboring cells. Since the CDMA mobile communication system is a self-interference system with limited interference and has near-far characteristics, in order to maximize the system capacity and coverage and ensure the quality of service communication, the base station (Node B) needs to allocate reasonable downlink power. [0003] In Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) system, according to the divisi...

AI Technical Summary

Problems solved by technology

[0007]The existing downlink initial power allocation method does not consider the downlink path loss and downlink time slot interference, so the allocated downlink initial transmit power is very inaccurate

If the UE is relatively close to the base station, the path loss is relatively small at this time, and the interference to the UE from the surrounding adjacent cells will be relatively small. If the downlink power allocated according to the current average is much greater than the appropriate initial downlink transmit power, it is Other UEs cause a large burst of interference impact, which will cause the quality of other UEs to deteriorate suddenly or even call drop, and will reduce the coverage and capacity of the cell

If the UE is far away from the base station, the path loss will be relatively large at this time, and the interference to the UE from the surrounding adjacent cells will also be relatively large. According to the current average distribution of downlink power, the size of the downlink initial transmission power will be less than the appropriate initial downlink transmission power, resulting in the UE Initial access failure or UE handover failure

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