An automatic barrier operator system for operating a gate or upward acting
garage door, for example, includes a controller for operating a
reversible motor, a base radio frequency transmitter and a base radio
frequency receiver. One or more remote control units include a radio
frequency remote receiver and remote transmitter. The controller is
operable to automatically close or open the barrier in response to a
query signal sent from the base transmitter to the remote receiver and
when the remote receiver is within range, returning a signal to effect
operation of the barrier. The system is operable to effect operation or
maintain the status quo of the barrier depending on the state of the
barrier and a particular signal or lack of signal received by the
controller from an authorized remote control unit or units. The system
provides essentially hands-free automatic operation of opening and
closing a garage door and the like.