How to load multiple signals in signal builder using single .mat file ?

I have a case where .mat file contains many sets of data in array format. How can I load that file in to signal builder ? I am facing the following error while trying to import to signal builder "File 'XXXX.mat' format does not comply with Signal Builder required format.There is no 'time' parameter defined." Can anybody help me in solving this issue ?

for example I have one set of data as mentioned below var.time = [0 1 1 5 5 8 8 10]; var.signals.values = [0 0 2 2 2 3 3 3]'; var.signals.dimensions = 1; var.signals.label = 'var'; save var.mat var

How to add another different set of data var1 to same var ?