Atmospheric gravity waves (GWs) excited by air disturbances in the troposphere transfer momentum and energy from the lower to the upper atmosphere, which plays a key role in the dynamics of the middle atmosphere. However, small-scale GWs are difficult to characterize due to the lack of high-vertical resolution atmospheric measurements. With the advent of Global Navigation Satellite Systems (GNSS) radio occultation (ROs) technique, vertical temperature profiles become available in the upper troposphere‒lower stratosphere (UTLS) region with high vertical resolution (<0.1km) and high accuracy (<0.5K). The retrieved temperature profiles can be used to capture and study the small-scale GWs. In this study, we present an analysis of small-scale GWs generated by hurricanes in the UTLS region, aiming to understand the GW characteristics and their variations with respect to the hurricane intensity and horizontal background wind regime. The wave-induced temperature perturbations are extracted from the RO temperature retrievals and analyzed using least squares spectral and wavelet analyses methods. We obtain GW spectra from which we estimate their wavelength and power that heuristically provide observational evidence to certain GW-generation theories, such as the pure thermal forcing mechanism and the overshooting convection. We also obtain two-dimensional spectrograms that further demonstrate the GW wavelength variation with respect to height, and visually illustrate the background wind filtering theory for the first time. Based on comparisons of GWs from different hurricanes, we consider a two-layer convection model to simulate the hurricane convection that innovatively connects the wave generation and dissipation mechanisms with the ambient background atmosphere.