Model 310B-33456 offers reliable intrusion detection in the presence of flammable,combustible or easily ignitable materials. The sensor is specifically designed to operate at oil refineries, chemical and petrochemical plants, petroleum or chemical storage facilities and other sites where hazardous materials are handled, processed or stored. Each 310B-33456 transmitter and receiver is packaged in a weatherproof, explosionproof enclosure with front access to controls and test points. The 310B-33456 operates at K-band (24.125Ghz) frequency, achieving performance not possible with X-band microwave links (10.5Ghz). Because antenna beam width is approximately 7.5 degrees in both the horizontal and vertical planes, the sensor will operate within very narrow corridors. Because K-band frequency is 2.5 times higher than X-Band, the multipath signal generated by an intruder is also 2.5 times higher and detection of slow-moving intruders is correspondingly better. With its superb beam control and higher multipath frequency, Model 310B-33456 provides unmatched detection performance. Phased Locked Loop (PLL) signal processing in the receiver increases detection probability by alarming on partial or complete beam interruption, increase or decrease in signal level or jamming by other transmitters. Its Automatic Gain Control (AGC) circuit permits the receiver to compensate for varying site conditions or changes in the weather. Operating at K-band frequency, Model 310B-33456 is inherently less susceptible to interference from airport landing systems, aircraft radar or other microwave intrusion systems. Four field-selectable modulation channels with narrow band PLL filters allow several Model 310B-33456 links to be used together without mutual interference.