A constraining sheath for use around an endoprosthesis, which may be a balloon expandable endoprosthesis but more preferably is a self-expanding prosthesis. The slide mechanism includes a slide member having a plurality of extensions that are biased toward the support rod. The present invention has excellent detection performance by receiving data with full order of diversity, which is multiple of the number of receiving antennas and the number of multipath, without complicated operation such as a decision feed equalizer.