Nearly Optimal Binary Index Tree in Mobile Real Time Environment

Indexing technology is hardly studied when data access is skew in real time system. On one hand indexing considers the probability of data accessed, on the other hand indexing needs to satisfy data real-time constraints, and meanwhile, the time complexity of arithmetic computing for indexing must be low. The nearly optimal binary index tree NOBIT is based on the idea of static optimal search tree. We introduce real-time weight when it deals with nodes probabilities weight so as to quickly construct a binary index tree with nearly optimal performance. The search process of NOBIT is similar to binary search, and its average time complexity is O(logN). The NOBIT considers the probability of accessed data and data which are accessed frequently are put into the front part of broadcast sequence so that average tuning time is shortened. Meanwhile, the NOBIT takes the real-time constraints of accessed data into account and data with rigid time constraints also are put into the front part of broadcast sequence so that success rate of data requested is improved.