Emergency vehicles carry a transponder that transmits a radio signal to change the traffic lights to green for them.
In a double conversion transponder , the signal received from the ground station is converted into IF , then the signal is filtered & amplified . Finally the IF signal is again upconverted to desired frequency and transmitted downwards.
Radio wave signal a transponder.
*"An automatic device that transmits a predetermined message in response to a predefined received signal. * A receiver-transmitter that will generate a reply signal upon proper electronic interrogation. " *Excerpted from Wikipedia ; see related link .
The word transponder is a combination of transmitter and responder. It is generally defined as a device which transmits a signal upon receiving a signal. It may be used as a beacon, as a signal repeater, an identification device, or any of numerous other uses.Please see the Wikipedia for an overview of the concept.
stop... A police officer assuming control of that intersection will have precedence over a traffic signal. If their signals are contrary to the traffic signal, you'll follow their signal.
The transponder, by sending a signal to the pit wall, is used to identify individual cars on the track, provide accurate lap timing and overall position in the race.
There is a transponder in every plane which gives signal where the plane is going.
Stop light is another name for a traffic signal.
traffic signal.
A signal light that is not working.
we control traffic by follows the signal