Finding the total capacity of two communication channels I have the transition matrices of two communication channels. I am able to find the capacity of each by performing an optimization calculation, however I need the total capacity of the two channels. The channels are not weakly symmetric so I don't think I am able to simply add the two capacities. I think what I need to do is perform the optimization calculation over the combined channels but I'm not sure how to do this. I think I need to construct a transition probability matrix but I'm not sure how to go about this. If anyone can give some advice on this I'd be grateful.

Thanks
If the channels are not coupled (i.e., their effect on the input is independent of each other) then their combined capacity is the sum of their individual capacities. See for example Wyner, Capacity of Product of Channels, who also considers the converse.