MICROWAVE_DOPPLER_INTRUSION_ALARM

Published:2009/6/30 2:41:00 Author:May | From:SeekIC

Mullard CL8960 X-band Doppler radar module detects movement of remote target by monitoring Doppler shift in microwave radiation reflected from target. Module consists of Gunn oscillator cavity producing energy to be radiated, mounted alongside mixer cavity that combines reflected energy with sample of oscillator signal. Transmitted frequency is 10.7 GHz. Doppler change is about 31 Hz for relative velocity of 0.45 m/s (1 mph) of relative velocity between object and module, giving AF output for velocities up to 400 mph. Filtered AF is applied through diode pump to trigger of silicon controlled switch TR3 that makes contacts of reed relay open for about 1 s.Relay action is repeated as long as intruder is in monitored area. Report covers circuit operation in detail.-J.E.Saw, Microwave Doppler Intruder Alarms. Mullard, London, 1976, Technical Information 36, TP1570, p 6.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Control_Circuit/Alarm_Control/MICROWAVE_DOPPLER_INTRUSION_ALARM.html

Print this Page | Comments | Reading(3)