The Multi-Zonal Remote Radiomonitoring System ST 152 is designed to detect the sources of electromagnetic radiation from devices intended for the unauthorized obtaining of information (eavesdropping devices), such as:
- radio microphones
- telephone radio transmitters
- hidden video cameras equipped with a radio channel for transmitting information
- unauthorized radio stations, wireless phones, and phones with wireless extensions
- unauthorized use of GSM and DECT cellular phones
The ST 152 comprises remote modules (hereafter, “M”) that are placed in locations where the use of unauthorized radio transmission devices is suspected. A single M covers a local zone and monitors the electromagnetic situation within in. The receiver of M consists of two blocks: a high-speed scanning receiver with a frequency range of 70–1200 MHz and a wideband field detector with a frequency range of 900–6000 MHz. Via a radio channel, data from M is transmitted to a base transceiver station connected to a PC.
The maximum number of simultaneously operating Ms is 32. Generally, this number is determined by the ability of the monitor to display the necessary information and scanning intervals of M (see Timing of data transmission between M and the base station). The specialized software allows controlling the system and displays information from M on a computer monitor.
The following information can be displayed: alarm signal, signal level, data transfer protocols (GSM, DECT, Bluethooth, WLAN), and spectrogram (with a frequency range of 70–1200 MHz). In addition, the system logs the events to a log file. *A local zone is space limited by the sensitivity of the scanning receiver and field detector of Mand interference in the zone of monitoring. *This number may vary in a wide range depending on the structure of the building, interference, and transmission frequency