In one embodiment, a passive transponder comprising a first circuit comprising a first attenuator, the first circuit configured to receive a first signal from at least one base station and coupled to a first node, a first rectifier coupled to the first node, the first rectifier configured in a forward direction to charge a first capacitor, and the first capacitor coupled to the first rectifier, the first capacitor configured to receive a charge from the attenuator sufficient for powering the passive transponder.

A wirelessly charging electronic lock device includes an electronic key and a electronic lock, a key code and a pre-stored matching code are pre-stored in the electronic key, an electronic lock code is pre-stored in the electronic lock, the electronic key includes a wireless charging device and a first wireless signal device, the wireless charging device charges the electronic device by wireless transmission, the electronic lock includes a wireless charging receiving device, a second wireless signal device, and a processing unit, the processing unit is configured to figure out a current matching code, the current matching code is compared with the pre-stored matching code, which is validated as to whether the electronic key matches with the electronic lock.

A utility cart includes a cabinet with a latch and strike lock, which is unlocked in the presence of a passive near field RFID key device and held open by a latch controller for sufficient time to allow the user to open the unlocked cabinet door. The latch is biased to its locking position, to which it returns when released by the controller. The latch includes a ramp surface which is engaged by the leading edge of the strike as the cabinet door is closed. In this way, the strike pushes the latch out of the way as it passes over the end of the latch, and the biased latch then returns to its locking position engaging a keeper in the strike as the keeper passes into position opposite the latch.

A method for accessing a vehicle includes determining a charge level of a battery of a first vehicle access device. The method also includes creating a permission scheme for a second vehicle access device. The method further includes communicating the permission scheme to a vehicle and accessing the vehicle with the second vehicle access device.