摘要:
A timing circuit that can function as an accurate persistent node in an RFID tag includes a power capture circuit for capturing power from a power source, and a counter circuit that provides a count representing a progression of time. The count can then be compared to a reference value representing a time constant of the circuit.
摘要:
A device for generating a seedless pseudo-random number, according to one embodiment, includes a first register containing a secret code; a second register containing a first random number generated locally and a second random number generated at a remote device; and an exclusive OR (XOR) circuit receiving output from the first and second registers and applying an XOR function to the outputs, a result of the XOR function being fed into the second register in a subsequent cycle.
摘要:
A device for generating a seedless pseudo-random number, according to one embodiment, includes a first register containing a secret code; a second register containing a first random number generated locally and a second random number generated at a remote device; and an exclusive OR (XOR) circuit receiving output from the first and second registers and applying an XOR function to the outputs, a result of the XOR function being fed into the second register in a subsequent cycle.
摘要:
A first embodiment provides a process and system for simple, secure exchange of random numbers between two devices by combining a random number and a secret code (e.g., password) to generate a first challenge code, extracting the random number using the password at the second device, combining the first random number with a second random number, and returning the combination to the first device, which extracts the second random number from the second challenge code using its first random number. A CRC can be added to authenticate the sender. Another embodiment provides a system and method for generating a seedless pseudo-random number. The Yet another embodiment provides a system and method for generating data encryption coding with variable clocking.
摘要:
A timing circuit that can function as an accurate persistent node in an RFID tag includes a power capture circuit for capturing power from a power source, and a counter circuit that provides a count representing a progression of time. The count can then be compared to a reference value representing a time constant of the circuit.
摘要:
A circuit tracks the total amount of time that a host device has spent in its high power “activated” state (an optionally idle and hibernate states) and thereby can estimate the total power consumed by the tag. A remote device can query the state of a counter storing a value representing this time to accurately determine how much of the energy has been consumed by the host device and how much time is left and/or how many more operations can be performed before the host device's battery is exhausted.
摘要:
Systems and methods for activating devices such as RFID tags includes activating a device if an activate command matches a value stored on the device. The activate command can also define which mode of operation or state the device will initiation in, and whether an additional function or functions is to be performed upon activation. Activate commands can also be dynamically assigned to devices in order to increase overall efficiency.
摘要:
A concentrator having a first surface, a second surface, and a concentrating surface disposed between the first surface and the second surface, the concentrating surface having a first profile which effects concentration of incident radiation at the first surface on to the second surface.
摘要:
In an active matrix electroluminescent display, a pixel containing a grounded conductive electric field shield between an EL cell and the switching electronics for the EL cell. In a method of fabricating the pixel, first, an EL cell switching circuit is formed, then an insulating layer is formed over the switching circuit and a conductive layer (the field shield) is formed over the insulating layer. A through hole is provided in the field shield such that an electrical connection can be made between the switching circuit and an EL cell. The EL cell is then conventionally formed on top of the shield layer. Consequently, the shield isolates the switching circuit from the EL cell and ensures that any electric fields produced in the EL cell do not interfere with the operation of the switching electronics. Furthermore, the switching circuitry for each cell contains two transistors; a low voltage MOS transistor and a high voltage MOS transistor. The low voltage transistor is controlled by signals on a data and a select line. When activated, the low voltage transistor activates the high voltage transistor by charging the gate of the high voltage transistor. This gate charge is stored between the gate electrode of the high voltage transistor and the electric field shield. Additionally, to improve the breakdown voltage of the high voltage transistor, a capacitive divider network is fabricated proximate the drift region of that transistor. As such, the network uniformly distributes an electric field over the drift region.
摘要:
An active storage or memory cell includes first and second high input impedance inverters cross coupled to form a flip-flop. The output impedance of the second inverter is significantly lower than the output impedance of the first inverter. Input signals are applied at, and information is read out from, a single input-output point common to the output of the second inverter and the input of the first inverter via a gating means connected between said input-output point and an input-output line which is turned on more slowly than it is turned off.