An active diversity antenna apparatus and methods of tuning and utilizing the same. In one embodiment, the active diversity antenna is used within a handheld mobile device (e.g., cellular telephone or smartphone), and enables device operation in several low frequency bands (LBs). The exemplary implementation of the active LB diversity antenna comprises a directly fed radiator portion and a grounded (coupled fed) radiator portion. The directly fed portion is fed via a feed element connected to an antenna feed. The coupled fed portion of the LB antenna is grounded, forming a resonating part of the low frequency band. A gap between the two antenna portions is used to adjust antenna Q-value. Resonant frequency tuning is achieved by changing the length of the grounded element. The LB feed element is disposed proximate the feed element of a high band diversity antenna, thus reducing transmission losses and improving diplexer operation.