Apparatus and methods are described, including a stent configured to be placed in a lumen. The stent includes a generally cylindrical stent body comprising a plurality of struts, and a plurality of antenna posts protruding longitudinally from an end of the stent body. Each of the antenna posts includes a proximal and distal portions, each of which is configured to be generally straight in the absence of any force being applied to the antenna post, and a compliant junction disposed between the proximal and distal portions, the proximal and distal portions being configured to flex with respect to one another about the compliant junction. An antenna is disposed annularly on the distal portions of the antenna posts, such that the antenna posts separate the antenna from the end of the stent body. Other applications are also described.