Schematic diagram of a duplexer. ... In the absence of the transmitter pulse both tubes act as open circuits. ... The gas tube across the receiver line causes the impedance looking toward the receiver from the junction to be zero, so all the echo power from the antenna is channeled to the receiver. ... Passive radar has some similarity to both passive infrared systems and active (radiating) radar systems.
|Title||:||Reader's Guide to the McGraw-Hill Encyclopedia of Science and Technology|