[0069] FIG. 13A is a schematic illustration of an image of the back of a sensor node integrated with a custom wireless energy harvesting unit, according to embodiments of the present disclosure; [0070] FIG. 13B is a schematic illustration of an image of the sensor node placed on the wrist of a user, while the second sensor node is placed on the shoulder of the user, according to embodiments of the present disclosure; and [0071] FIG. 13C is a schematic illustration of a screenshot of a smartphone application displaying data received from wireless sensor nodes on the shoulder and wrist (shown as nodes 4 and 5 respectively on the application) via propagation of Bluetooth signals along the metamaterial textile, according to embodiments of the present disclosure. [0072] The foregoing will be apparent from the following more particular description of example embodiments of the disclosure, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale; emphasis instead being placed upon illustrating embodiments of the present disclosure. DETAILED DESCRIPTION [0073] Electromagnetic waves at optical frequencies can be confined on metallic surfaces in localized excitations called surface plasmons. Because these modes propagate conformally along the surface of the metallic material and interact strongly with nearby objects through an evanescent field, they are widely used as interconnection elements in photonic devices. Although surface plasmons do not feature in bulk materials at radio-frequencies, concepts in metamaterials may enable these modes to be engineered by structuring conductive surfaces. [0074] According to embodiments of the present disclosure, clothing structured with conductive textiles may support surface plasmon-like modes at radio communication frequencies and thereby provide a platform to mold the propagation of radio-waves around the body of a user. By physically localizing wireless signals onto the body of a user, such metamaterial textiles may enable personal networks of wireless sensors and devices that are highly efficient, immune to interference, and inherently secure. [0075] Existing metamaterial designs, however, have not been designed for use on the human body, whose complex electromagnetic environment poses challenges in tissue losses and interactions with nearby wireless devices. [0076] According to the present disclosure, these challenges are overcome to enable efficient and secure interconnection of sensor networks with radio surface plasmons. In contrast with conventional