An energy-efficient, wide-band, and compact wireless sensor reader remotely interrogates an implanted wireless inductive-capacitive (LC) sensor in order to measure a physiologic parameter of interest within a human body. The wireless sensor reader generates an instantaneous, spike-shaped, high-amplitude, low-energy pulse to excite the wireless LC sensor, causing it to emit a ring-down signal. The wireless sensor reader subsequently receives, amplifies, and filters the ring-down signal. Next, the wireless sensor reader digitizes the ring-down signal and transfers the digitized ring-down signal to a processing unit. The processing unit computes a Fast Fourier Transform (FFT) of the digitized ring-down signal and then locates the resonant frequency of the LC sensor using a threshold peak detection technique.