Patent ID: 8693965

Claim:
A communication system for non-motorized carts, the system comprising: a transmitter configured to transmit a radio-frequency control signal to a region, the transmitter comprising: a housing; a solar panel disposed in a solar panel housing portion of the housing, the solar panel housing portion comprising an optical element that is substantially transparent to visible light and configured to transmit the visible light to the solar panel; a rechargeable power storage medium disposed in the housing, the rechargeable power storage medium configured to be recharged by the solar panel; a directional antenna disposed in the housing, the directional antenna configured to be at least partially rotatable; and a radio-frequency transmitter disposed in the housing, the radio-frequency transmitter electrically coupled to the directional antenna to transmit the radio frequency control signal, the radio frequency control signal producing a control field that defines a control region; a transceiver configured to be disposed on a non-motorized cart that is movable relative to the transmitter, the transceiver configured to detect the control signal when the transceiver is in the control field and to transmit a radio tracking signal in response to the control signal; and a controller configured to monitor an aspect of the non-motorized cart at least partly based on the tracking signal.