Abstract: The present invention provides a digital circuit comprising an inverter gate delay line and a delay adjustment circuit. The inverter gate delay line comprises a series of a plurality of inverter gates that receives a serial data.

Abstract: The present invention relates to a parameterization method for a converter (1, 2) of the speed controller type, the said converter (1, 2) being connected to an electrical load (3) by means of an electrical cable (4) comprising at least two conductors, the method consisting in: generating common-mode current on the electrical cable (4) starting from a pulsed voltage comprising a first voltage edge (11, 13) and a second voltage edge (12, 14) delayed by a delay time (T) with respect to the first voltage edge (11, 13), measuring the common-mode current generated, making the delay time (T) between the two voltage edges (11, 12, 13, 14) generated vary, and determining an optimal delay time (T2) starting from a quantity (Ipeak, Ieff) representative of the common-mode current measured for the various values of the delay time (T).

Abstract: The pulse generator comprises: a delay line arranged to receive a digital input signal and to produce a plurality of delay line output signals; first and second pulse generator blocks comprising logic circuitry arranged to generate a plurality of successive first output pulses in response to said different delay line output signals; and pulse combiner circuitry arranged to combine said first output pulses to produce second output pulses. The first pulse generator block is arranged to be responsive to rising edges of said input signal, and the second pulse generator blocks is responsive to falling edges of said input signal. Thus, both rising and falling edges of said input signal are used to create pulses. The device can be used in impulse radio transmitters and receivers.

Abstract: In a second system that generates a clock signal that is synchronized with a first system, a control voltage value that controls the second oscillator such that the second system is synchronized with the first system is monitored according to the phase difference between a reference signal that is generated using the output of a first oscillator in the first system and the output of a second oscillator, whereby frequency fluctuation that occurs due to age deterioration of the first oscillator is detected.

Abstract: An internal clock generator that modulates a high-frequency clock signal to a low-frequency signal to transmit the low-frequency signal if a transmission line for transmitting the high-frequency clock signal is long, and then restores the transmitted low-frequency signal to the high-frequency signal. The internal clock generator includes a first signal generation unit for receiving a first signal having a first frequency and generating a second signal having a second frequency that is lower than the first frequency, and a second signal generation unit for receiving the second signal and generating a third signal having a frequency equal to the first frequency. Here, the third signal is used as a signal for controlling an operating time point of an internal circuit of a synchronous memory device.

Abstract: A QKD system that includes a dual-mode pulse generator capable of operating as both a clock-based pulse generator and a delay-based pulse generator while minimizing the limitations of these two types of pulse generators is disclosed. When the pulse generator operates in “delay mode,” the smallest output pulse width possible corresponds to the minimum set point delay between the two delay circuits. The largest possible output pulse width corresponds to the difference between the maximum and minimum of the delay circuits. The delay mode is used to send relatively narrow optical pulses between the QKD stations to establish a quantum key. When the dual-mode pulse generator operates in “clock mode,” the output of one of the delay circuits is blocked so that the output of the gate depends solely on the output of other delay circuit. This limits the lower pulse width interval to that of the retimer clock, but allows for arbitrarily long (wide) optical pulses.

Abstract: Provided is a voltage level shift circuit including: a first voltage level shift circuit formed of a P-channel enhancement type transistor (M1) and an N-channel depletion type MOS transistor (M3); and a second voltage level shift circuit formed of a P-channel enhancement type transistor (M2) and an N-channel depletion type MOS transistor (M4). In the voltage lever shift circuit, a cascode circuit using an N-channel depletion type transistor (M5) is serially connected to the first voltage level shift circuit, a cascode circuit using an N-channel depletion type transistor (M6) is serially connected to the second voltage level shift circuit, and a unit for complementarily controlling bias voltages of the respective cascode circuits. As a result, an output signal of the voltage level shift circuit connected to an input of a differential amplifier circuit, for expanding an input voltage range of a signal, is not affected by fluctuations in power supply voltage.

Abstract: The voltage generation circuit that have a standard voltage generation circuit that generates a reference voltage; a minimum voltage setting circuit that sets a minimum voltage; a voltage setting circuit that has a plurality of resistive elements and a plurality of gate transistors connected to a plurality of the resistive elements, and gradually sets voltage by switching a plurality of the gate transistors to switch a combination of a plurality of the resistive elements; a differential amplifier that has two input terminals and one output node, one input terminal is connected to the reference voltage that is generated by the standard voltage generation circuit, another input terminal is connected to the minimum voltage setting circuit and the voltage setting circuit that has a plurality of resistive elements and a plurality of gate transistors connected to a plurality of the resistive elements, and the output node shows the result of the difference voltage of these two inputs; a pump control circuit that out

Abstract: Protection methods and protection systems for semiconductor devices with diode junctions. The protection methods and protection systems detect the anomalies in the behavior of the junction and protect the device from damage.

Abstract: An apparatus, method and system are described for providing a low power replica biased regulated supply voltage without the size requirements of using a large resistor coupled between the source of a master transistor and ground. Instead, a source of a replica transistor diode may be biased with a bias voltage, and the gate and drain of the diode may be biased with a current bias. Additional descriptions provide the supply voltage without the size requirements of a resistor coupled between a source of one or more pass transistors and ground. Instead, the source of the pass transistor(s) may be biased with a “leaker” current.

Abstract: Provided is a band gap constant-voltage circuit capable of achieving a quick startup time to thereby preventing an output voltage from being stabilized at 0 V due to noise or the like even under the normal condition. The band gap constant-voltage circuit according to the present invention includes: an output voltage detecting circuit for monitoring a voltage at an output terminal; and a current source which has a current value controlled through an output of the output voltage detecting circuit, in which the current source supplies a bipolar transistor constituting a level shifter circuit with a current when the voltage at the output terminal is lower than a predetermined voltage.

Abstract: A power gating circuit of a signal processing system includes a low dropout linear regulator, a control circuit, and an output circuit. The low dropout linear regulator includes a first transistor, an operational amplifier, a first resistor, a second resistor, and an output end. The output circuit includes a fourth transistor and a step-down circuit. The control circuit controls output voltage of the output circuit according to a control signal.

Abstract: The present invention discloses a fast switching current mirror circuit and method for generating fast switching current. The circuit and method for fast switching of a current mirror with large MOSFET size will save space and current consumption.

Abstract: An apparatus for biasing a transistor, comprising: a controllable bias generator; a test circuit; a digital Mth order differentiator responsive to an output of the test circuit; and a controller responsive to the digital Mth order differentiator for controlling the controllable bias generator; wherein the test circuit is configured to calculate an Lth order derivative of the transistor's performance.

Abstract: An operational amplifier including: a differential pair of transistors coupled to a pair of input signals; and a pair of floating-gate transistors coupled to the differential pair of transistors, wherein the pair of floating-gate transistors are operable for reducing an offset voltage of the operational amplifier.

Abstract: The present invention introduces methods and systems to amplify digital audio signals for driving speakers. First, digital audio signals are converted to PWM audio signals by a liner PWM modulator that is open-loop. Then, PWM audio signals are amplified by a Class D audio amplifier that has at least one feedback loop.

Abstract: A medical apparatus includes an extracorporeal power source that transmits electrical power via a radio frequency signal to a medical device implanted inside an animal. The extracorporeal power source has a Class-E amplifier with a choke and a semiconductor switch connected in series between a source of a supply voltage and circuit ground. An output node of the amplifier is formed between choke and the switch and connected to a transmitter antenna. A shunt capacitor couples the amplifier's output node to the circuit ground. Controlled operation of the switch produces bursts of the radio frequency signal that are pulse width modulated to control the amount of energy being sent to the implanted medical device.

Abstract: A multi-channel amplifier has inputs via which input signals can be fed to the multi-channel amplifier. The input signals are amplified into output signals by amplifier channels of an amplification stage of the multi-channel amplifier and then are emitted via outputs of the multi-channel amplifier. An adjustment device is associated with the amplification device that allows dynamic adjustment of a limit power, up to which the respective output signal can be amplified, for each output. The limit power can be set to a maximum value for each output. The multi-channel amplifier is fashioned such that the sum of the limit powers of all outputs can always be simultaneously emitted independent of the current setting of the limit powers, but such that the sum of the limit powers is always smaller than the sum of the maximum values of all outputs. Such a multi-channel amplifier is particularly suitable for use in a transmission arrangement for radio-frequency signals.

Abstract: A signal amplifier includes a discrete-variable-gain amplifying unit, a gain of which takes a discrete value and changes stepwise, a linear-variable-gain amplifying unit connected in series to the discrete-variable-gain amplifying unit, a gain of which changes continuously, control-signal outputting means for detecting a level of an output signal from a series connection circuit of the discrete-variable-gain amplifying unit and the linear-variable-gain amplifying unit and outputting a control signal corresponding to a difference between the level of the output signal and a reference voltage set as a comparative level to control the gain of the linear-variable-gain amplifying unit, and gain-switching control means for controlling to switch the gain of the discrete-variable-gain amplifying unit when the control signal deviates from a setting range for the control signal that is set according to a variable gain range of the discrete-variable-gain amplifying unit.

Abstract: The invention is a power converter that coverts audio signal energy into a regulated DC power. The invention uses the audio output sources available on most modern transportation systems such as airplanes, trains and busses and converts the electrical output of those sources to an electrical output that can be used to recharge or allow extended use of various portable electronic devices. The main components of the invention include a rectifier section which is designed to rectify and amplify input AC signal energy. This is followed by a current storage section which accumulates the input energy and determines if the stored energy is sufficient to be output to the regulator component. The regulator component converts stored energy component signal into regulated DC output.

Abstract: A technique is provided for achieving reduction in size of an electronic device with a power amplifier circuit, while enhancing the performance of the electronic device. An RF power module for a mobile communication device includes first and second semiconductor chips, a passive component, and first and second integrated passive components, which are mounted over a wiring board. In the first semiconductor chip, MISFET elements constituting power amplifier circuits for the GSM 900 and for the DCS 1800 are formed, and a control circuit is also formed. In the first integrated passive component, a low pass filter circuit for the GSM 900 is formed, and in the second integrated passive component, a low pass filter circuit for the DCS 1800 is formed. In the second semiconductor chip, antenna switch circuits for the GSM 900 and DCS 1800 are formed. Over the upper surface of the wiring board, the second semiconductor chip is disposed next to the first semiconductor chip between the integrated passive components.

Abstract: A Class-E power amplifier includes a choke and a switch connected in series between a source of a supply voltage and circuit ground and connected to an inductively coupled coil. An output node of the amplifier is formed between choke and the switch and connected to a transmitter antenna. A shunt capacitor couples the amplifier's output node to the circuit ground. A feedback signal, indicating an intensity if the signal at the amplifier output node is used to vary the input signal to the Class-E power amplifier and thereby control operation of the switch.

Abstract: In a differential output circuit, a second amplifier has a positive terminal connected to a second fixed potential and a negative terminal to a fifth switch at a first terminal. First and second switches are connected at a point connected to the fifth switch at a second terminal and to a first load. Third and fourth switches are connected at a point connected to the fifth switch at a third terminal and to a second load. The second terminal is connected to the first terminal when the second and third switches turn on. The third terminal is connected to the first terminal when the first and fourth switches turn on.

Abstract: Disclosed is a differential amplifying circuit including an amplifying circuit, wherein 1) a drain of a sixth transistor is connected to a drain of an eighth transistor, and a drain of a tenth transistor is connected to a drain of a fourth transistor, and 2) a ratio between a total of gate widths of the fourth (or eighth) and tenth (or sixth) transistors (converted per unit gate length, and gate widths that follow are the same)and a gate width of a fifth (or ninth) transistor is nearly proportional to a current ratio between a first (or third) and second (or fourth) current source circuits, the gate width of the fourth (or eighth) transistor being equal to or more than that of the tenth (or sixth) transistor.

Abstract: A transconductance stage providing gain control includes an input stage to convert a first differential input voltage and a second differential input voltage to a first intermediate current and a second intermediate current, respectively. An output stage generates a first output current signal and a second output current signal based on the first and second intermediate currents, respectively. The output stage includes a first plurality of output transistors coupled to a first plurality of corresponding switch resistors and a second plurality of output transistors coupled to a second plurality of corresponding switch resistors. The number of activated switch resistors of the first plurality of switch resistors determines a gain of the first output current signal and a number of activated switch resistors of the second plurality of switch resistors determines a gain of the second output current signal.

Abstract: The present invention relates to an amplifier and, more particularly, to an adaptive linear amplifier with low power consumption and a high linearity. The adaptive linear amplifier according to the present invention comprises amplification means and a bias controller. The amplification means comprises a main transistor and an auxiliary transistor unit. The main transistor and the auxiliary transistor unit are coupled to each other. The bias controller controls a bias voltage applied to the main transistor and the auxiliary transistor unit.

Abstract: A voltage reference forces a constant voltage at the inputs to an amplifier, thereby negating a need for a dummy detector on the non-active input of the amplifier.

Abstract: A method and an apparatus are provided for impedance matching using an analog circuit. The method comprises providing the analog circuit to substantially match a start impedance to an end impedance and tuning a performance parameter of an associated circuit using the analog circuit operating at a high power level. The analog circuit may transform the start impedance to the end impedance using a characteristic impedance in a range above the start impedance and the end impedance. By reconfiguring the analog circuit, the associated circuit may operate at one of a first, second, or higher order frequency bands. By using a matching transformation process, reconfigurable matching circuits for medium and/or high power applications may be provided by using available lower power reconfiguration elements. In the matching transformation process, the intermediate impedance at which the reconfiguration is performed is higher than the matching processes used for lower power reconfiguration elements.

Abstract: A resonator pattern made of superconductive material is disposed over a first surface of a base substrate made of dielectric. An adjustment substrate made of dielectric is disposed facing the first surface at a distance from the first surface. The adjustment substrate is supported by a support mechanism for supporting the adjustment substrate in such a manner capable of changing an angle between the first surface and a surface of the adjustment substrate facing the base substrate. A superconductive filter is provided which can shift a center frequency of a filter band and suppress disturbance of a waveform of a filter characteristic, with a simple method.

Abstract: A piezoelectric plate electric connection structure aims to receive an input voltage from a voltage source and goes through a polarization process to deliver an output voltage. It has an input electrode on a piezoelectric plate to receive input from the voltage source and an output electrode to deliver the output voltage that are located on two surfaces normal to the polarization direction. One surface has an independent electrode. Another surface has two separated electrodes. The input electrode and output electrode are respectively the independent electrode and one of the separated electrodes. The input and output electrodes are spaced by the piezoelectric plate which is dielectric and pressure-resistant. Thus discharge phenomenon can be prevented between the input electrode and the output electrode.

Abstract: An FBAR filter added with a balance-unbalance conversion function is provided. The FBAR filter includes: an FBAR filter device having two unbalanced terminals, and which performs filtering of a signal between such terminals; and a balance-unbalance converter having one unbalanced terminal and one pair of balanced terminals, and which performs balance-unbalance conversion of the signal. The unbalanced terminal and the unbalanced terminal are connected, and filtering and balance-unbalance conversion of the signal is performed between the unbalanced terminal and the balanced terminals. The characteristics of the FBAR filter device are brought forth in the filtering of the signal.

Abstract: An object of the present invention is to provide a piezoelectric thin film device including a single or a plurality of film bulk acoustic resonators wherein a frequency impedance characteristic is unsusceptible to spuriousness. In a film bulk acoustic resonator, a piezoelectric thin film is supported by a support substrate via an adhesive layer. An upper electrode and a lower electrode each having predetermined pattern are formed on upper and lower surfaces of the piezoelectric thin film. Further, on the upper surface of the piezoelectric thin film, an additional film for adding a mass to an outside of an excitation region is formed as superposed on the upper electrode.

Abstract: There is provided a piezoelectric thin film device with its frequency impedance characteristic unsusceptible to spuriousness. A film bulk acoustic resonator has a configuration where an adhesive layer, a lower electrode, a piezoelectric thin film, and an upper electrode are laminated in this order on a support substrate. A drive section of the upper electrode and a drive section of the lower electrode are opposed to each other with the piezoelectric thin film interposed therebetween. The respective drive section has a slender two-dimensional shape, with magnitude in its longitudinal direction being not less than twice, more desirably four times, and further desirably ten times, as large as magnitude in its widthwise direction.

Abstract: An acoustic resonator includes a first electrode, a second electrode, and a barium strontium titanate (BST) dielectric layer disposed between the first electrode and the second electrode, where the acoustic resonator is switched on as a resonator with a resonant frequency if a DC (direct current) bias voltage is applied across the BST dielectric layer. The acoustic resonator is also switched off in no DC bias voltage is applied across the BST dielectric layer. Furthermore, the resonant frequency of the acoustic resonator can be tuned based on a level of the DC bias voltage, with the resonant frequency increasing as the level of the DC bias voltage applied to the BST acoustic resonator increases.

Abstract: A system and method of carrier less modulation is described in this disclosure that uses SAW filters as a modulator in addition to their conventional use as filters for band limiting an UWB system. This system and method is primarily designed to be used with any integer cycle, ultra-wide band or impulse type modulation and more particularly is designed to work with a method of modulation named xMax. This technique exploits the impulse response of the SAW filter producing a carrier less impulse radio system with limited bandwidth, low average power, but high peak power.

Abstract: A band-pass filter (10) includes a first resonator (140), a second resonator (160), a third resonator (180), an input part (100), and an output part (120). The input part is for receiving electromagnetic signals. The first resonator is electronically connected to the input part. The second resonator is parallel to the first resonator. The output part electronically connected to the second resonator, for transmitting the electromagnetic signals from the second resonator. The third resonator is disposed between the first resonator and the second resonator, and parallel to and offset from the first resonator and the second resonator. Each of the first resonator, the second resonator, and the third resonator has an asymmetrical shape. This structure of the band-pass filter not only has a smaller profile, but also provides a wide frequency range.

Abstract: There is disclosed an ortho-mode transducer fabricated as a single piece. The ortho-mode transducer may include a first surface having an aperture defining a common port, a second surface having an aperture defining a vertical port, and a third surface having an aperture defining a horizontal port. The second and third surfaces may be essentially parallel and normal to the first surface. A common waveguide may coupled to the common port, the common waveguide supporting orthogonal vertical and horizontal modes. A vertical branching waveguide may couple the vertical mode between the vertical port and the common waveguide while rejecting the horizontal mode. A horizontal branching waveguide may couple the horizontal mode between the horizontal port and the common waveguide while rejecting the vertical mode.

Abstract: A substrate including strip conductors with a wiring pattern that connects contact areas to one another. The strip conductors have a small strip conductor width. The contact areas and/or the strip conductors form a narrow connection pitch and include electrically conductive carbon nanotubes.

Abstract: An electromagnet having at least one access port oriented perpendicularly to the electromagnet's central axis. The magnet has a conventional helical winding along its central axis. However, at some point along the length of the axis, the pitch of the helical winding is greatly increased in order to create a region with a comparatively low turn density. One or more ports are provided in this region. These ports provide access from the magnet's central bore to the magnet's exterior. A sample can be placed in the central bore near the ports. A beam traveling down the central bore, or through one of the radial ports, will strike the sample and be scattered in all directions. The ports allow access for instrumentation which is used to evaluate the scattered beam.

Abstract: A circuit breaker for a double-break mechanism includes a current interrupting section having a contact mechanism. The contact mechanism includes first and second fixed contactors arranged in parallel and having fixed contacts, and a bridging movable contactor having an arm with movable contacts opposing the fixed contacts. A magnetic plate may be interposed in a middle region between two pairs of the fixed and movable contacts extending along a path of switching movement of the movable contactor. Partition walls formed of organic polymer material may be provided to stand along the path of the movable contactor. The partition walls sandwich each pair of the fixed contact and the movable contact to form a narrow gap arc extinguishing space between the partition walls.

Abstract: An apparatus and method in which three or more permanent or electromagnets are mounted in a support structure on rotatable axes in spaced relationship to each other such that the magnetic lines of force of the same magnetic polarity continuously repel each other to generate a field in “opolarity.” The magnets are focused to a generally central spherical shell-like space and upon continuous synchronous rotation generate a magnetic vortex. Magnetic materials or materials that can be made susceptible to the effects of a magnetic field are placed in a material processing portion of a material containment vessel that is positioned in the magnetic vortex where upon continuous synchronous rotation of the magnets, the material is subjected to the quantum and wave mechanical effects of the magnetic vortex so as to be compacted, aggregated, separated, reaggregated, manipulated, tumbled, and levitated and in the process the physical, chemical, and magnetic properties and chemical composition of the material is changed.

Abstract: A transformer (10), coupled to a circuit board (20) defining a receiving hole (210), includes a base (110) having a first end portion (110a) and an oppositely disposed second end portion (110b), a bobbin assembly (120) disposed between the first end portion and the second end portion, and a post (140) disposed on the base. The post is received in the receiving hole for positioning the transformer on the circuit board.

Abstract: An ignition coil includes a coil portion that has a primary coil, a secondary coil, and an outer core. The outer core is arranged on a radially outer side of both the primary coil and the secondary coil. A fitting member, which is in a substantially cylindrical shape, has an inner periphery via which the fitting member is fitted to the outer core. A connector case has a fit hole via which the connector case is fitted to an outer periphery of the fitting member. The connector case connects with an axial end of the coil portion via the fitting member. The fitting member includes an embedded member that is at least partially embedded in the fitting member. The embedded member is formed of a material that is different in Young's modulus from a material constructing the fitting member.

Abstract: An inductive power supply system for providing power to one or more inductively powered devices. The system includes a mechanism for varying the physical distance or the respective orientation between the primary coil and secondary coil to control the amount of power supplied to the inductively powered device. In another aspect, the present invention is directed to an inductive power supply system having a primary coil and a receptacle disposed within the magnetic field generated by the primary coil. One or more inductively powered devices are placed randomly within the receptacle to receive power inductively from the primary coil. The power supply circuit includes circuitry for adjusting the power supplied to the primary coil to optimize operation based on the position and cumulative characteristics of the inductively powered device(s) disposed within the receptacle.

Abstract: An electronic fuse for an integrated circuit and a method of fabrication thereof are presented. The electronic fuse has a first terminal portion and a second terminal portion interconnected by a fuse element. The fuse element has a convex upper surface and a lower surface with a radius of curvature at a smallest surface area of curvature less than or equal to 100 nanometers. Fabricating the electronic fuse includes forming an at least partially freestanding dielectric spacer above a supporting structure, and then conformably forming the fuse element of the fuse over at least a portion of the freestanding dielectric spacer, with the fuse element characterized as noted above. The dielectric spacer may remain in place as a thermally insulating layer underneath the fuse element, or may be removed to form a void underneath the fuse element.

Abstract: A retention arrangement for a circuit interrupter to ensure that ensures the retention of the circuit interrupter in its mounting. The retention arrangement cooperates with a latch member of the mounting for the circuit interrupter. Accordingly, the circuit interrupter is retained in its mounting even where the dimensions of the circuit interrupter may vary from the nominal specified dimensions.

Abstract: A temperature sensitive switching module for mounting against an outer surface of a container to control operation of a heater heating contents of the container, the switching module including: a temperature sensitive element arranged to deform in dependence upon its temperature to operate a switch; the temperature sensitive element being arranged within the module such that when the module is mounted on the surface of the container, the temperature sensitive element is disposed adjacent the surface of the container with one surface of the element exposed to the surface of the container so as to provide for direct radiated or conducted heat transfer from the container to the element over substantially the whole of the facing surface of the element.

Abstract: The present invention provides an overheat protection device which is capable of effectively preventing a secondary battery from overheating. In the overheat protection device (20), a variable resistive element(s) (11) of which resistance varies depending on a temperature is located on and thermally combined with a certain position(s) of an electrical system (1), and a switching element (15) for controlling a current depending on an applied voltage thereto is arranged so as to control the current flowing through the electrical system (1). When the certain position of the electrical system (1) comes to be under a high temperature condition, the variable resistive element (11) interrupts the current flowing through the electrical system (1) by changing the applied voltage to the switching element (15).

Abstract: Disclosed are a subscriber station authentication method, a protocol configuration method, and a device thereof in a wireless portable Internet system. In the subscriber station authentication method, an authentication mode between a subscriber station (10) and a base station (20) is negotiated, and the authentication mode is negotiated by the base station (20) according to the authentication mode negotiation. The authentication modes include an authentication mode based on the IEEE 802.16 privacy standard protocol and an authentication mode based on the standardized authentication protocol of the upper layer. Authentication is performed by the base station (10) in the case of the authentication mode based on the IEEE 802.16 privacy standard protocol, and the authentication is performed through message transmission using a diameter protocol between a base station (10) and an authentication server (40) in the case of the authentication mode based on the standardized authentication protocol of the upper layer.

Abstract: Automatic recognition apparatus (100, 700) includes multiple automatic recognition subsystems (102, 104, 106) that are cable of producing estimates of the probability that a subject matches a particular identity, a probability estimate combiner (108) that receives estimates from the multiple automatic recognition subsystems (102, 104, 106) and produces a combined estimate, and a decayer that (111) that decreases the certainty of the combined estimate over time while avoiding changing estimates to values that would suggest strong information contrary to the initial values of the combined estimates.