Abstract: In one embodiment, a noise cancellation circuit includes: a window generator to generate a window having a first set of samples; a band splitter to split the window into pairs of symmetric frequency components; a processing circuit, for each of the pairs, to: compare a first magnitude of a first symmetric frequency component to a second magnitude of a second symmetric frequency component and modify one of the components based at least in part on the comparison; an integrator to integrate the pairs output from the processing circuit; and a second window generator to generate a second window having a second set of samples.

Abstract: A radio frequency (RF) signal is received in a receiver, and various counts based on information from the signal can be obtained. Counts of a number of samples of the RF signal exceeding first and second thresholds can be accumulated during an accumulation window. From the first of these counts, it can be determined if the count exceeds a first metric corresponding to a first predetermined count value, and if so, a gain of an RF gain element can be reduced. From the second of these counts it can be determined if this count exceeds a second metric corresponding to a second predetermined count value, and if not, the gain can be increased.

Abstract: A system and method for demodulating signals are disclosed. In a particular embodiment, the method includes receiving a signal at an input and determining a first noise estimate of the signal. The method also includes providing a first output indicating a second noise estimate of the signal at a primary carrier frequency and providing a second output indicating a third noise estimate of the signal at a secondary carrier frequency.

Abstract: A radio frequency (RF) signal is received in a receiver, and various counts based on information from the signal can be obtained. Counts of a number of samples of the RF signal exceeding first and second thresholds can be accumulated during an accumulation window. From the first of these counts, it can be determined if the count exceeds a first metric corresponding to a first predetermined count value, and if so, a gain of an RF gain element can be reduced. From the second of these counts it can be determined if this count exceeds a second metric corresponding to a second predetermined count value, and if not, the gain can be increased.

Abstract: A wireless handset includes a long range wireless transceiver for selectively providing an inbound communication and an outbound communication through a wireless telephone network. A battery monitor module monitors a remaining power of a battery and produces a control signal when the remaining power compares unfavorably to a reserve power threshold. A processing module allows an outbound communication to an allowed recipient when the control signal is asserted, and prohibits an outbound communication to a disallowed recipient when the control signal is asserted.

Abstract: A stereo decoder includes a first digital filter for producing a first filtered composite audio signal and a second digital filter for producing a second filtered composite audio signal. A sum/difference network produces a left channel signal and a right channel signal. A processor executes operational instructions that calculate a first corner frequency of a first digital filter based on a signal quality of the FM signal, calculate a first set of filter coefficients for the first digital filter based on the first corner frequency and an approximation of a filter transform, calculate a second corner frequency of a second digital filter based on the signal quality, and calculate a second set of filter coefficients for the second digital filter, based on the second corner frequency and the approximation of the filter transform.

Abstract: A receiver includes a mixing module for mixing an input signal by at least one mixing sequence to produce a mixed signal. The mixed signal is filtered to produce a first filtered signal. A first downsampler downsamples the first filtered signal to produce a first decimated signal, wherein the decimation period is not a multiple of the mixing period.

Abstract: A method for enabling at least a portion of a multiple function handheld device begins by enabling at least a portion of a digital audio functionality in response to a first mode selection. The method continues by disabling wireless communication functionality in response to the first mode selection.

Abstract: A method for reducing adjacent channel interference begins by determining a desired channel of a radio frequency (RF) signal. The method continues by determining a plurality of potential local oscillations for the desired channel. The method continues by determining a proximal power level of an image frequency of each of the plurality of potential local oscillations to produce a plurality of proximal power levels. The method continues by selecting one of the plurality of potential local oscillations for down converting the desired channel based on the plurality of proximal power levels.

Abstract: A system and method for demodulating signals are disclosed. In a particular embodiment, the method includes receiving a signal at an input and determining a first noise estimate of the signal. The method also includes providing a first output indicating a second noise estimate of the signal at a primary carrier frequency and providing a second output indicating a third noise estimate of the signal at a secondary carrier frequency.

Abstract: A radio receiver, optionally used in conjunction with a handheld audio system, includes a radio stage for processing a received radio signal into an audio signal. An audio stage produces an audio output, based on the audio signal. An overload monitor detects an overload condition in the radio stage and generates an overload signal in response to the detected overload condition. A controller controls the audio output in response to the overload signal.

Abstract: Method for operating and testing a sensor assembly (210). The sensor assembly (210) preferably includes accelerometers with axes of sensitivity orthogonal to each other. The method preferably includes determining sensor tilt angle, determining the position of the sensor, and synchronizing the operation of the sensor.

Abstract: A plurality of seismic sensors calibration method (100) includes: an assembling so that sensors are coupled with each sensor positioned with its axis of sensitivity in a different spatial direction calibration system step (105), a rotating sensors step (110), a measuring sensors output signals step (115), a sensor output signal processing step (120) and a storing calibration coefficient(s) step (125).

Abstract: A method and an apparatus are provided for matching the response of hydrophones 22 to the response of geophones 24 and significantly reducing response variations between hydrophones caused by inherent characteristics. The method includes the steps of determining a capacitance 66 for each of the hydrophones 22 in an operating environment, configuring a filter 36 based on the capacitance 66, and modifying a response of a channel of the hydrophone 22 using the filter 36. The apparatus includes an acquisition unit 20 having a geophone 24 and a hydrophone 22, a recording unit 30, a processing unit 31 and a filter 36 for correcting for variation between hydrophones 22 and changing a first order low frequency response of the hydrophone 22 to appear like a second order response like that of the geophone 24.