Keyless vehicle entry system employing portable transceiver having low power consumption
AssigneeTRW Inc.
InventorGeorge P. Lambropoulos
Life of this patent
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Abstract
A portable transceiver is provided for use with a remote keyless entry system for controlling the locking-unlocking functions of a motor vehicle door lock and causing performance of a vehicle function. The transceiver includes a signal receiver for, when turned on, receiving an interrogation signal and responding thereto by transmitting a coded reply signal requesting performance of a vehicle function. A power supply is carried by the portable transceiver for purposes of supplying operating power for use by the signal receiver. A timer and controller are arranged to turn-on transceiver operation for a predetermined period of time when an interrogation signal and timed power pulse are received concurrently.
Claims8
A portable transceiver for use in a remote keyless entry system for controlling the locking-unlocking functions of a motor vehicle door lock and wherein said system includes a vehicle transceiver for periodically transmitting an interrogation signal and receiving a coded reply signal and responding thereto for causing performance of a vehicle function, said portable transceiver comprising:
- transmitter/receiver means for, when turned on, receiving a said interrogation signal and responding thereto by transmitting a said coded reply signal requesting performance of a vehicle function;
- power supply means carried by said portable transceiver for supplying operating power for use by said transmitter/receiver;
- timer means for receiving said operating power and having a first mode of operation for periodically supplying power pulses for each turning on said transmitter/receiver means for a given period of time corresponding with that of a said power pulse;
- said timer means having a second mode of operation for providing continuous power to said transmitter/receiver means;
- and
- control means for controllably switching said timer means between said first and second modes of operation;
- said control means including means for switching said timer means from said first mode of operation to said second mode of operation for a predetermined period of time when said transmitter/receiver means concurrently receives a said interrogation signal and a said power pulse so that said transmitter/receiver means is then turned on for said predetermined period of time and wherein said predetermined period of time is of a duration corresponding with that for said transmitter/receiver means to receive said interrogation signal and for transmitting a said coded reply signal.
Dependencies are inferred from the claim text.