Abstract: A system and method of generating electrode stimulation signals for an implanted multi-channel electrode array of a cochlear implant includes processing an acoustic audio signal with a bank of filters. Each filter in the bank of filters is associated with at least one channel having an electrode. The bank of filters includes a first band pass filter that produces a broadband signal b(t) with frequencies that substantially cover at least one of a pitch frequency range of 100 Hz to 400 Hz and a first format range of 400 Hz-1000 Hz. At least one electrode associated with the first band pass filter is activated with electrode stimulation signals based, at least in part, on the broadband signal b(t). The filter bank may include at least one electrode associated with one or more filters other than the first band pass filter, the one or more filters producing signals having only higher frequencies than broadband signal b(t).

Abstract: An implant includes a humidity sensor for generating a signal indicative of humidity within the implant. A controller within the implant receives the signal indicative of humidity, and controls the implant based on the signal indicative of humidity.

Abstract: A method, system and computer product for simultaneously activating at least two electrodes in a multichannel electrode array is presented. The method includes calculating pulse amplitudes of the electrodes in the multichannel array by taking into account parameters of spatial channel interaction reflecting geometric overlapping of electrical fields from each electrode. Calculating is based, at least in part, on place-independent impulse responses characterized by a first exponential decay constant ? at a first side of the electrode and a second exponential decay constant ? at a second side of the electrode, such that the first exponential decay constant ? is the same for each electrode in the array, and the second exponential decay constant ? is the same for each electrode in the array.

Abstract: An implantable electronic system is described. An implantable power supply includes multiple power input ports for receiving an externally generated power supply signal, and multiple power output ports for developing a detected power signal. An implantable prosthetic processing module includes multiple prosthetic processing input ports connected by wire to the power output ports for receiving the detected power signal, and multiple prosthetic processing output ports for developing a prosthetic stimulation signal output for electrically stimulating target neural tissue. Each of the multiple ports is adapted to operate without developing a dc potential.

Abstract: A method, system and computer product for simultaneously activating at least two electrodes in a multichannel electrode array is presented. The method includes calculating pulse amplitudes of the electrodes in the multichannel array by taking into account parameters of spatial channel interaction reflecting geometric overlapping of electrical fields from each electrode. Calculating is based, at least in part, on place-independent impulse responses characterized by a first exponential decay constant ? at a first side of the electrode and a second exponential decay constant ? at a second side of the electrode, such that the first exponential decay constant ? is the same for each electrode in the array, and the second exponential decay constant ? is the same for each electrode in the array.

Abstract: A system and method of generating electrode stimulation signals for an implanted multi-channel electrode array of a cochlear implant includes processing an acoustic audio signal with a bank of filters. Each filter in the bank of filters is associated with at least one channel having an electrode. The bank of filters includes a first band pass filter that produces a broadband signal b(t) with frequencies that substantially cover at least one of a pitch frequency range of 100 Hz to 400 Hz and a first format range of 400 Hz-1000 Hz. At least one electrode associated with the first band pass filter is activated with electrode stimulation signals based, at least in part, on the broadband signal b(t). The filter bank may include at least one electrode associated with one or more filters other than the first band pass filter, the one or more filters producing signals having only higher frequencies than broadband signal b(t).

Abstract: An implant includes a humidity sensor for generating a signal indicative of humidity within the implant. A controller within the implant receives the signal indicative of humidity, and controls the implant based on the signal indicative of humidity.

Abstract: A cochlear implant system has an implantable portion that includes a stimulator module for producing for the auditory system of a user an electrical stimulation signal representative of an acoustic signal. The implantable portion further includes a battery for supplying power to the stimulator module, a receiver module for receiving an electrical power signal across the skin of a user, and a recharge module that uses the electrical power signal to recharge the battery. The recharge module recharges the battery at less than the maximum recharge rate.

Abstract: An implant system includes an external portion adapted for placement external to a user, and an implantable portion adapted for placement internal the user. One of the internal portion and the external portion includes a first password for transmitting to the other one of the internal portion and the external portion. The other one of the internal portion and the external portion includes a second password. A match between the first password and the second password causes a first mode of operation.

Abstract: An implantable electronic system is described. An implantable power supply includes multiple power input ports for receiving an externally generated power supply signal, and multiple power output ports for developing a detected power signal. An implantable prosthetic processing module includes multiple prosthetic processing input ports connected by wire to the power output ports for receiving the detected power signal, and multiple prosthetic processing output ports for developing a prosthetic stimulation signal output for electrically stimulating target neural tissue. Each of the multiple ports is adapted to operate without developing a dc potential.

Abstract: A method of activating at least two electrodes in a multichannel electrode array using channel specific sampling sequences is presented. A channel specific sampling sequence is defined for each electrode, the sequence having a particular duration, pulse amplitude distribution, and number of pulses. A weighting factor is applied to the channel specific sampling sequence. Each electrode in the multichannel electrode array is then simultaneously activated using sign-correlated pulses, the sign-correlated pulses based on parameters of spatial channel interaction reflecting geometric overlapping of electrical fields from each electrode, non-linear compression, and each electrode's weighted channel specific sampling sequence.

Abstract: A rectifier circuit includes first and second input terminals for receiving a rectangular wave input voltage, and first and second output terminals for providing a rectified dc output voltage. A first switch is coupled between the first input terminal and a first node, the first node being coupled to the first output terminal. A second switch is coupled between the second input terminal and the first node. A third switch is coupled between the first input terminal and a second node, the second node being coupled to the second output terminal. A fourth switch is coupled between the second input terminal and to the second node. The first switch and fourth switch are gated on when the input voltage is of a first polarity; and the second switch and the third switch are gated on when the input voltage is of a second polarity opposite the first polarity so as to provide an output voltage having a magnitude substantially equal to the magnitude of the input voltage.

Abstract: A system and method for adaptive sigma-delta modulation. The system includes a input stage that produces a difference signal representing the difference between an analog input signal x(n) and a analog feedback signal z(n), the amplitude of the analog input signal x(n) within a first range [?a, +a]. An accumulator stage produces a accumulated signal that is a function of an accumulation of the difference signal, the accumulator stage transforming the accumulation of the difference signal so as to increase average magnitude while ensuring instantaneous magnitude does not exceed a predetermined value. A quantization stage produces a quantized digital signal y0(n) representing the accumulated signal. Based on the quantized digital signal y0(n), a adaptation stage produces a digital output signal z0(n), which is converted to the analog feedback signal z(n) by a digital-to-analog converter stage.

Abstract: A stimulation system including a stimulator having a multi-channel electrode array utilizing a monopolar electrode configuration. A processor is operatively coupled to the stimulator. The processor is configured to determine a channel interaction (CI) sequence using simultaneous, sign-correlated pulses and channel interaction compensation. The CI sequence has a CI pulse rate and a CI mean pulse amplitude, and produces resulting potentials that are substantially equal to desired potentials at given positions relative to the multi-channel array. The CI sequence may include temporal gaps between pulses, wherein the processor may be configured to increase the CI pulse rate, such that the temporal gap between pulses is decreased. Furthermore, the processor may be configured to reduce the pulse amplitude of the CI sequence while increasing pulse phase duration, such that charge per pulse remains substantially unchanged and the temporal gap between pulses is decreased.

Abstract: In accordance with one embodiment of the invention, a method of activating electrodes in a multichannel electrode array is provided. Each channel is associated with a different electrode in the array. At least two groups of channels in the multichannel electrode array are selected, wherein at least one of the selected groups includes a plurality of channels. One or more channels in each selected group is selected, and the electrodes associated with each selected channel are activated. The steps of selecting at least one channel in each selected group, and activating the electrodes associated with each selected channel are repeated, such that the selected channels in at least one selected group varies.

Abstract: A system and method for adaptive sigma-delta modulation. The system includes a input stage that produces a difference signal representing the difference between an analog input signal x(n) and a analog feedback signal z(n), the amplitude of the analog input signal x(n) within a first range [?a, +a]. An accumulator stage produces a accumulated signal that is a function of an accumulation of the difference signal, the accumulator stage transforming the accumulation of the difference signal so as to increase average magnitude while ensuring instantaneous magnitude does not exceed a predetermined value. A quantization stage produces a quantized digital signal y0(n) representing the accumulated signal. Based on the quantized digital signal y0(n), a adaptation stage produces a digital output signal z0(n), which is converted to the analog feedback signal z(n) by a digital-to-analog converter stage.

Abstract: A digital finite impulse response bandpass filter is described. Analog to digital conversion (A/D) of an input signal uses a Sigma-Delta (&Sgr;-&Dgr;) converter, resulting in a digital sequence representation of the input signal. A low-pass FIR filter convolves the binary sequence to produce a low-pass vector, and a digital comb filter defined by at least one set of weighted and time-shifted unit impulses convolves the low-pass vector with the comb filter weights. An envelope detector detects a bandpass envelope of the digital FIR bandpass filter. Also described is a filter bank of a plurality of such digital FIR filters arranged in parallel. A square root of a sum of squares of the convolution products of the low-pass vector with the comb filter weights is calculated to estimate the bandpass envelope.

Abstract: A digital finite impulse response bandpass filter is described. Analog to digital conversion (A/D) of an input signal uses a Sigma-Delta (.SIGMA.-.DELTA.) converter, resulting in a digital sequence representation of the input signal. A low-pass FIR filter convolves the binary sequence to produce a low-pass vector, and a digital comb filter defined by at least one set of weighted and time-shifted unit impulses convolves the low-pass vector with the comb filter weights. An envelope detector detects a bandpass envelope of the digital FIR bandpass filter. Also described is a filter bank of a plurality of such digital FIR filters arranged in parallel.A square root of a sum of squares of the convolution products of the low-pass vector with the comb filter weights is calculated to estimate the bandpass envelope.