| PHS(Personal Handy System),which is also called Xiao Ling tong, originated from Japan in 1990s and subsequently extended to the other countries and regions rapidly.According to statistics,the user number of PHS has got 91.12 million till Dec.30,2006 in china.Following which,the value-added service of PHS especially the traffic of SMS is skipping up.Facing the growth momentum of SMS,the short message service center system of UT expands the capacity widely.We find that PHS has distinct technology characteristics during operation that the improvement of the processing ability of SMS center system doesn't equal to the linear growth of the whole system's processing ability.The characteristics of the wireless technology of PHS lead to the bottleneck of processing ability of SMS. This research just aims at developing the transmitting ability of SMS without changing current basic mechanism of PHS.Firstly,the best point of flow control is determined based on the analysis of the different performance of the traffic of SMS between the GSM system and PHS system combining the characteristics of PHS's wireless technology and flow control theory.Secondly,in SMS center,the flow control is realized aiming at PA combining with the strategy of slow growth and rapid reduction by setting unified initial threshold;The flow control of PG is also realized according to the restriction of the PG queue and the conditions of transmission;The performance of group sending of SMS is optimized by judging the user state,according to the division method of PG.The SMS system of PHS is improved and optimized by combining the effective setting of the priority of QOS,which improves the processing ability greatly. Finally,after a lot of field tests, the adaptive flow control measures is proved to be effective,and the processing speed also reached the expected effect. |
