3D maximum likelihood estimation positioning algorithm based on RSSI ranging

Based on the analysis of 3D maximum likelihood estimation positioning algorithm, RSSI ranging error directly affects the overall positioning accuracy of the algorithm, so weighted maximum likelihood estimation positioning algorithm is put forward. It is inversely proportional to the square of distance and positioning accuracy of the algorithm through theoretical derivation, thus diagonal weight matrix of the distance's inverse square is introduced to traditional maximum likelihood estimation algorithm. The experimental results show that with the same error range, the weight matrix's positioning algorithm reduces positioning error by 0.45-1.87 m and improves the precision of positioning.