A method for verification of a vector execution unit design. Furthermore, the top and bottom boards are pivoted to the main board via the first and second connecting portions, so that the top and bottom boards can be folded to further save transportation space. A matrix H of dimension M\xd7N representative of the multi-antenna propagation channel is estimated and the data are sent according to a mode of transmission selected from among at least two multi-antenna modes. Meanwhile, a second processor wishes to obtain ownership of the cache line and sends a read request to a memory directory associated with the home memory of the cache line.