Hello jie yu,
Regarding your inquiry about installing the MPC toolbox for Matlab 2013 version, I would like to provide you with some guidance. You can refer to the documentation available at the following link: https://www.control.lth.se/research/tools-and-software/mpctools/. This documentation should outline the procedure for installing the MPC toolbox separately.
However, I would like to inform you that instead of downloading the MPC toolbox separately, it is recommended to consider upgrading to a newer version of MATLAB that includes the integrated MPC functionality. By doing so, you can benefit from the latest features and improvements in the MPC toolbox.
Hope this helps!