Abstract: An apparatus includes a housing having a printed circuit board having a top surface and a bottom surface. The top surface of the printed circuit board forms an outer surface of the housing. The apparatus further includes a bottom-port microphone sensor mounted on the bottom surface of the printed circuit board. The printed circuit board has a port opening formed therein to provide an acoustic path from outside of the housing to the microphone sensor. A method of detecting ultrasonic signals includes receiving ultrasonic signals within a port opening of a printed circuit board forming part of a surface of a housing, and directing ultrasonic signals to a microphone sensor secured to a printed circuit board through the port of the printed circuit board.

Abstract: Methods and apparatus for recording and analyzing echolocation calls using zero crossing and/or digital sampling (full spectrum analysis) techniques, and for optimizing trigger thresholds used to activate recording in response to detection of an echolocation call.

Abstract: An apparatus includes a housing having a horn with a mouth and a throat. The mouth of the horn is larger in cross section than the throat of the horn. The housing further includes a waveguide providing communication from the throat of the horn. The apparatus further includes a printed circuit board supported by the housing and a microphone sensor. The microphone sensor is mounted to a printed circuit board. The waveguide provides communication from the throat of the horn to the microphone sensor. The apparatus may be configured to include a housing having a waveguide providing communication to an interior of the housing, a printed circuit board supported by the housing within the interior of the housing, and a microphone sensor.

Abstract: An apparatus includes acoustic equipment and an enclosure to support the acoustic equipment. The enclosure includes a front cover member, a middle cover member, a back cover member, and a hinge to connect the front cover member to the back cover member. The hinge enables the movement of the front cover member and the back cover member between an open position and a closed position. The middle cover member is disposed between the front cover member and the back cover member, with the middle cover member being connected to the hinge to enable movement of the middle cover member and the back cover member between an open position and a closed position. The enclosure further includes a first latch configured to releasably secure the middle cover member to the back cover member, and a second latch configured to releasably secure the front cover member to the back cover member.

Abstract: Methods and apparatus for using Fourier techniques to detect and isolate the fundamental frequency sweep of echolocation calls produced by bats, or of other narrow-band whistles as produced by other kinds of animals such as birds and whales. According to one example, a Fourier transform is applied on blocks of input samples to produce output frames, and a narrowband frequency modulated signal is detected and traced through the output frames. A filter is applied in each frame to attenuate frequencies above or below the narrowband signal, and an inverse Fourier transform is applied to produce an output signal. The resulting signal may then be analyzed with zero crossing techniques to measure the precise instantaneous frequency sweep.

Abstract: A method and apparatus for measuring frequency and amplitude of an input signal representative of an echolocation call. In one example, a system includes a combination of a digital sampling channel and a zero crossing measurement channel that are configured to simultaneously measure the echolocation call and produce a combined, time-synchronous data set representative of the echolocation call.

Abstract: A method for listening to ultrasonic animal sound signals comprises: obtaining a plurality of input samples at an input sample rate, the plurality of input samples including at least one sequence of samples corresponding to an instance of an intermittently occurring animal sound signal; receiving a frame including at least two of the plurality of input samples; selecting a fraction of the samples as output samples, the fraction of the samples including a sample containing the at least one sequence of samples corresponding to an instance of an intermittently occurring animal sound signal; and transmitting the output samples at an output sample rate slower than the input sample rate.

Abstract: A method and apparatus for measuring frequency and amplitude of an input signal representative of an echolocation call. In one example, a system includes a combination of a digital sampling channel and a zero crossing measurement channel that are configured to simultaneously measure the echolocation call and produce a combined, time-synchronous data set representative of the echolocation call.

Abstract: A method for listening to ultrasonic animal sound signals comprises: obtaining a plurality of input samples at an input sample rate, the plurality of input samples including at least one sequence of samples corresponding to an instance of an intermittently occurring animal sound signal; receiving a frame including at least two of the plurality of input samples; selecting a fraction of the samples as output samples, the fraction of the samples including a sample containing the at least one sequence of samples corresponding to an instance of an intermittently occurring animal sound signal; and transmitting the output samples at an output sample rate slower than the input sample rate.

Abstract: A method and apparatus for powering a device, such as a data recorder or other device, according to an adjustable schedule. One example of the apparatus includes a programmable timer having an alarm output, a power regulator having an enable input coupled to the alarm output, a controller coupled to the power regulator and to the programmable timer, the controller being configured to receive operating power from the power regulator, and a powered device coupled to the power regulator and configured to receive power from the power regulator. The regulator has an operating state in which the operating power is provided to the powered device and an idle state in which the operating power is not provided to the powered device. The regulator is configured to be activated into the operating state by activation of the alarm output and deactivated into the idle state by deactivation of the alarm output, under the control of the controller.

Abstract: A method and apparatus for powering a device, such as a data recorder or other device, according to an adjustable schedule. One example of the apparatus includes a programmable timer having an alarm output, a power regulator having an enable input coupled to the alarm output, a controller coupled to the power regulator and to the programmable timer, the controller being configured to receive operating power from the power regulator, and a powered device coupled to the power regulator and configured to receive power from the power regulator. The regulator has an operating state in which the operating power is provided to the powered device and an idle state in which the operating power is not provided to the powered device. The regulator is configured to be activated into the operating state by activation of the alarm output and deactivated into the idle state by deactivation of the alarm output, under the control of the controller.

Abstract: Relatively powerful hand-held computing devices, Digital Signal Processors, Audio signal processing technology, voice recognition technology, expert systems, Hidden Markov Models, and/or neural networks are employed in a device capable of real-time automated species identification by listening to bird vocalizations in the field, analyzing their waveforms, and comparing these waveforms against known reference samples.

Abstract: A method for listening to and comparing high-frequency sounds such as those produced by birds and insects by people suffering from high-frequency hearing loss, common among the aging population. Live sound is received by a microphone to produce an electrical signal. The signal is then digitized and transformed such that high frequency sounds are shifted to lower frequencies making them easier to hear. Recordings of known sources are also transformed for comparison.

Abstract: A method of access control in which an authority may limit the content a client may download to a trusted device comprises: the authority making content, and a content descriptor containing information about the content, available to a client; the authority providing an access key to a client; the client presenting the access key and a requested content descriptor to a trusted device for download; and the trusted device accepting or rejecting the requested download as determined by the access key and content descriptor presented. Numerous variations are possible. Apparatus for limiting distribution of content obtained together with an access key in which a shared secret is encoded from a computer executing a server process comprises: a trusted device including a verifier that verifies the encoded shared secret and a content acceptor that only accepts content when the shared secret is verified.

Abstract: Relatively powerful hand-held computing devices, Digital Signal Processors, Audio signal processing technology, voice recognition technology, expert systems, Hidden Markov Models, and/or neural networks are employed in a device capable of real-time automated species identification by listening to bird vocalizations in the field, analyzing their waveforms, and comparing these waveforms against known reference samples.