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Emission Measurements of a Contraband Wireless Device Jammer at a State Prison

Report ID
Technical Report TR-19-541
September 01, 2019
Frank H. Sanders; Geoffrey A. Sanders; John E. Carroll

This report describes emission spectrum measurements of a wireless jammer device operated temporarily inside a South Carolina state prison maximum security housing block. The measurements were intended to demonstrate the operation of the jammer in four commercial mobile radio service (CMRS) bands between 730 MHz to 2.155 GHz. Spectrum measurements of the jammer emissions were performed indoors and outdoors with two measurement bandwidths. Measurements at each location were performed with the jammer on versus off, so as to show the relative power levels of the jamming and ambient CMRS signals at each location. This report’s data can be applied in future electromagnetic compatibility (EMC) analyses. However, the data provide no information as to whether a CMRS wireless device can or cannot perform its intended communications function in the presence of a competing signal of specified strength. Only thorough theoretical analysis, well-engineered simulation and modeling, plus selected measurements in controlled (laboratory) environments can objectively quantify the impact of interfering transmissions on CMRS wireless devices.

Keywords: electromagnetic compatibility (EMC); harmful interference; denial-of-service jamming; radio jamming; commercial mobile radio service (CMRS) jamming; communications jamming; micro-jammer; wireless device jamming