A single focus wide-angle lens module includes a fixed aperture diaphragm, a first lens, a second lens, a third lens and a fourth lens arranged from an object side to an image side in a sequence of: the first lens, the diaphragm, the second lens, the third lens and the fourth lens. The method includes receiving a sequence of received symbols over the channel whose quality is to be measured. Each of the extension members include a guide member slidably positioned thereon. When a user query is received that includes one of the entities, query suggestions are returned to the user based on indexed relationships corresponding to the entity named in the user query. The ribs are configured to provide an interference fit engagement between the sidewall of the base member and the sidewall of the lid when the lid is attached to the base member. The system implements a communication protocol in which the external communication device interrogates any implantable medical devices within range to establish one-to-one communication links for purposes of exchanging data andor programming the medical devices.