A method for improving the spatial reuse of a wireless network, comprising selecting a medium access slot type for scheduling concurrent transmissions in the wireless network ; assigning reservations to the selected MAS ; and applying the selected MAS to source nodes and sink nodes of the wireless network. The stent includes a coated primary unit having a hollow cylindrical body fabricated by knitting a shape-memory alloy wire to make a net structure, with both an enlarged diameter part and a coat layer. The device may be provided with the capability for adjustment of both the voltage level and frequency of the current as well as the capability to enable operation of the device only upon payment to a service provider of a fee.