Wireless Localization Method Based on AHP-WKNN and Amendatory AKF

Pseudocode 1

The pseudocode of the proposed algorithm.

Input: measured RSS matrix at test point and fingerprint database

Output: the optimal position estimation

1. Initializing the amendatory AKF and AHP, and setting the first column of as the initial value for the in amendatory AKF;

2. ;

3. the number of iterations of the amendatory AKF;

4. whiledo:

 5. setting the threshold based on Equations (21) and (22)

 6. reducing noises of in the tth column of based on Equations (12), (14) and (16) and getting the output ;

 7. calculating the covariance of Equation (18);

 8. comparing with . If , fix to get based on Equations (23) and (24), and use for the next iteration. Otherwise, use instead;

 9. updating Equation (13), (17), (19) and (20);

 ;

11. end while

12. Calculating the Euclidean distances between and each fingerprint in the database. Sorting these distances and choose nearest fingerprints’ coordinates;

13. Based on and fingerprints, using AHP to build hierarchical model and judgment matrices;

14. Examining the consistency of each judgment matrix and determining the weight vector of each judgment matrix based on Equation (7) and (8);

15. Getting the weights of fingerprints’ coordinates that are needed to realize localization based on Equation (9);

16. Based on the coordinates and their corresponding weights, using Equation (6) to estimate the optimal position ;

17. return.