Side-Channel Analysis (SCA) is an increasingly well-known method for non-invasively extracting information from unintended “side-channel” emissions given off by electronic devices. The common method for extracting side-channel information is via a near-field antenna probe placed in the vicinity (i.e., millimeters) of the target device. The antenna detects and amplifies the radio-frequency (RF) emissions given off by the device and transmits the information for analysis and testing. Side-channel attacks are most known for their utility in cryptanalytics; however, they can also be used to fingerprint devices or even determine the digital state of the system. In this work, characterization studies on a 1- GHz antenna using Riscure’s RF probe station are performed. For RF-SCA, the ultimate limits of signal sensitivity and frequency response are determined by the antenna characteristics. In addition, the effective source-receiver distance (SRD), cross-talk and spatial signal averaging at various SRDs have to be characterized for signal attenuation and normalization. From our testing, it appears that the Riscure probe has a peak frequency response at about 200 MHz. For example, the 418MHz antenna had multiple peaks at 130 MHz, 172 MHz, 213 MHz, and 370 MHz, as well as multiple less significant protrusions at higher frequencies. The BeeHive100C probe peaked at exactly 200 MHz but had a couple of side-lobes in the 600-800 MHz range. The Pharad 30-512 MHz antenna peaked at a slightly lower 193MHz, although, some response was observed in the 600-800 MHz range as in the other antennas. The Pharad 225-6000MHz antenna exhibited a similar peak but lesser roll-off and an elevated response at increased frequencies than its predecessor.