Portable IMSI

Portable IMSI catchers are compact, field-deployable cellular interception platforms that simulate a legitimate mobile network base station, causing target handsets within range to register onto the monitoring device rather than the actual network operator infrastructure. Law enforcement and intelligence units use these systems to identify mobile devices present in a target area, intercept communications, and collect subscriber identity data without requiring network operator cooperation or fixed installation infrastructure at the surveillance location.

The system transmits a spoofed base station signal across 2G GSM, 3G UMTS, and 4G LTE frequency bands, broadcasting at sufficient power to dominate the legitimate network signal within the target coverage radius. Mobile devices in the coverage area perform a normal network registration procedure with the IMSI catcher, transmitting their International Mobile Subscriber Identity and International Mobile Equipment Identity numbers during the handshake sequence. The system logs these identifiers for all devices that register, building a presence database of handsets in the monitored area. Additionally, targeted interception directs specific IMSI or IMEI numbers toward downgraded 2G connections where voice call encryption is weaker, allowing call audio capture on identified target devices within the coverage zone.

Coverage radius on portable units runs between 500 meters and 2 kilometers in urban environments, with directional antenna configurations extending effective range in open terrain conditions. Furthermore, direction-finding antenna arrays on advanced portable configurations triangulate target handset position within the coverage area, narrowing physical location to within 10 to 50 meters for close-target follow operations. System weight on backpack-portable configurations runs between 5 and 15 kilograms including battery pack, antenna assembly, and processing unit.

Battery runtime supports between 4 and 8 hours of continuous operation per charge, with vehicle power connection extending operational duration for static surveillance deployments. Moreover, encrypted data storage on the processing unit logs all captured IMSI, IMEI, and call data with timestamp and GPS coordinate records for chain-of-custody documentation.