A monopole exciter antenna installed in the hinge slot region of a slim laptop with metal covers is presented. The exciter antenna comprises a feeding strip and a matching strip that form a two-branched monopole structure. A small antenna size of 35 × 8 mm2 enables installation in the hinge slot region between the upper metal cover and the base metal cover of a slim laptop. The proposed exciter antenna can be integrated with the metal surroundings (metal covers and metal hinges) to enhance the operating bandwidth and thus cover the long-term evolution/wireless wide area network band with high radiation efficiency. The antenna efficiency is approximately 68–88% in the lower band and 52–78% in the upper band.