Abstract: An example apparatus includes a transducer to receive a reference signal and a reflected signal, the reflected signal being the reference signal after being reflected of a target; a filter to generate a band-pass reference signal and a band-pass reflected signal by filtering (A) reference signal samples associated with the reference signal and (B) reflected signal samples associated with the reflected signal; a correlator to generate a first correlation by correlating the reference signal samples with the reflected signal samples and a second correlation by correlating the band-pass reference signal with the band-pass reflected signal; and a delay estimator to determine a distance to the target based on the first correlation (coarse delay) and the second correlation (fine delay) and output a signal including the distance to the target.

Abstract: An optical time of flight system includes a transmitter and a receiver. The transmitter is configured to generate a modulation signal having a modulation signal frequency that varies as a function of time, generate an optical waveform with amplitude modulation corresponding to the modulation signal, and direct the optical waveform toward a field of view (FOV). The receiver is configured to receive the optical waveform reflected off of an object within the FOV and determine a distance to the object based on a time of flight from the transmitter to the object and back to the receiver.

Abstract: An optical transmitting system for distance measuring includes a signal generator, a laser diode coupled to the signal generator, and an optics device. The signal generator is configured to generate a first plurality of electrical signals. The laser diode is configured to generate a first plurality of optical waveforms that correspond with the first plurality of electrical signals. The optics device is configured to receive the first plurality of optical waveforms and direct the first plurality of optical waveforms toward a first plurality of scan points that form a scan region within a field of view (FOV). A first signal type, a first signal duration, a first signal amplitude, or a first signal repetition frequency of the first plurality of optical waveforms is based on a first desired range of the first plurality of scan points.

Abstract: An optical distance measurement system includes a transmission circuit and a receive circuit. The transmission circuit is configured to generate narrowband intensity modulated light transmission signals over a first band of frequencies and direct the narrowband light transmission signal toward a target object. The receive circuit is configured to receive reflected light off the target object, convert the reflected light into a current signal proportional to the intensity of the reflected light, filter frequencies outside a second band of frequencies from the current signal to create a filtered current signal, and convert the filtered current signal into a voltage signal. The second band of frequencies corresponds with the first band of frequencies.

Abstract: Methods and apparatus to determine a distance to a target using coarse and fine delay estimation based on a narrowband transmit signal are disclosed. An example apparatus includes a transducer to receive a reference signal and a reflected signal, the reflected signal being the reference signal after being reflected of a target; a filter to generate a band-pass reference signal and a band-pass reflected signal by filtering (A) reference signal samples associated with the reference signal and (B) reflected signal samples associated with the reflected signal; a correlator to generate a first correlation by correlating the reference signal samples with the reflected signal samples and a second correlation by correlating the band-pass reference signal with the band-pass reflected signal; and a delay estimator to determine a distance to the target based on the first correlation (coarse delay) and the second correlation (fine delay) and output a signal including the distance to the target.

Abstract: An optical distance measuring system includes a transmitter and a receiver. The transmitter is configured to generate a first optical waveform and direct the first optical waveform toward a first scan point within a field of view (FOV). The receiver is configured to receive the first optical waveform reflected off a first object within the FOV, direct the first optical waveform reflected off the first object to a first photodiode group of an array of photodiode elements, and determine a distance to the first object based on a time of flight of the first optical waveform from the transmitter to the first object and back to the receiver.

Abstract: Methods and apparatus to determine an accurate distance to a target using reference signal interpolation is disclosed. An example apparatus includes an interpolator to receive a first sample of a reference signal and a second sample of a reference signal; and interpolating a reconstructed reference signal sample based on the first and second samples, the reconstructed reference signal corresponding to the reference signal; a correlator to generate a plurality of phase-shifted, reconstructed reference signals; and correlate each of the plurality of phase-shifted, reconstructed reference signals with a reflected signal; and an optimal phase selector to determine an optimal phase based on the correlations and output a distance to a target based on the optimal phase.

Abstract: Described examples include an integrated circuit having an analog-to-digital converter operable to receive an input signal derived from a light signal and convert the input signal to a digital received signal, the analog-to-digital converter operable to receive the input signal during at least one window. The integrated circuit further has a receiver operable to receive the digital received signal, the receiver operable to determine a distance estimate of an object from which the light signal is reflected based on the digital received signal. In an example, the window locations are chosen to correspond to the locations of maximum slope in the signal.

Abstract: Methods and apparatus to determine a distance to a target using coarse and fine delay estimation based on a narrowband transmit signal are disclosed. An example apparatus includes a transducer to receive a reference signal and a reflected signal, the reflected signal being the reference signal after being reflected of a target; a filter to generate a band-pass reference signal and a band-pass reflected signal by filtering (A) reference signal samples associated with the reference signal and (B) reflected signal samples associated with the reflected signal; a correlator to generate a first correlation by correlating the reference signal samples with the reflected signal samples and a second correlation by correlating the band-pass reference signal with the band-pass reflected signal; and a delay estimator to determine a distance to the target based on the first correlation (coarse delay) and the second correlation (fine delay) and output a signal including the distance to the target.

Abstract: In described examples, a spatial light modulator (SLM) receives light from a field of view. The SLM includes a two-dimensional array of picture elements in rows and columns. In response to a transmit scan beam that illuminates the field of view, a portion of the two-dimensional array is impacted by light reflected from a region of interest. The portion of the two-dimensional array is determined. Light is directed from the portion of the two-dimensional array to a photodiode. Light that impacts the two-dimensional array outside the portion is directed away from the photodiode.

Abstract: Described example aspects include an integrated circuit includes a timing controller configured to select a selected time slot in a measurement period having a plurality of time slots and a transmit driver configured to provide a transmit signal in accordance with the selected time slot, in which the transmit signal is transmitted to an optical transmitter. The integrated circuit also includes a range estimator configured to receive a received signal after the selected time slot from an optical receiver that is configured to receive a reflection of light transmitted by the optical transmitter off an object, the range estimator configured to determine an estimated distance of the object based on the received signal.

Abstract: Described examples include an integrated circuit that includes an encoder configured to modulate a driving signal for an optical transmitter with a plurality of encoded pulses corresponding to a code, in which the driving signal is transmitted to the optical transmitter periodically. The integrated circuit also includes a demodulator configured to receive a received signal from an optical receiver that is configured to receive a reflection of light transmitted by the optical transmitter off an object, the demodulator configured to discriminate the plurality of encoded pulses in the received signal and estimate a distance of the object.

Abstract: In described examples, an integrated circuit includes a modulator configured to modulate a driving signal for an optical transmitter with a narrow band modulation signal in which the driving signal with a fixed duration is transmitted to the optical transmitter periodically. The integrated circuit also includes a demodulator configured to receive a signal from an optical receiver that is configured to receive a reflection of light transmitted by the optical transmitter off an object, the demodulator configured to discriminate the narrow band modulation signal and estimate a distance of the object using the narrow band modulation signal.

Abstract: An optical distance measuring system includes a transmitter, a beam steering device, and a receiver. The transmitter is configured to generate a first plurality of optical waveforms. The beam steering device is configured to steer the first plurality of optical waveforms to a first plurality of scan points that form a non-uniform scan region within a field of view (FOV). The receiver is configured to receive the first plurality of optical waveforms reflected off of a first plurality of target objects within the non-uniform scan region and determine a distance to each target object of the first plurality of target objects based on a time of flight from the transmitter to each target object of the first plurality of target objects and back to the receiver.

Abstract: An optical distance measuring system includes a first transmitter, a first solid state device, and a receiver. The first transmitter is configured to generate a first optical waveform. The first solid state device is configured to receive the first optical waveform and steer the first optical waveform toward a target object. The receiver is configured to receive the first optical waveform reflected off of the first target object and determine a distance to the first target object based on a time of flight from the transmitter to the first target object and back to the receiver.

Abstract: In some developing interconnect technologies, such as chip-to-chip optical interconnect or metal waveguide interconnects, misalignment can be a serious issue. Here, however, a interconnect that uses an on-chip directional antenna (which operates in the sub-millimeter range) to form a radio frequency (RF) interconnect through a dielectric waveguide is provided. This system allows for misalignment while providing the increased communication bandwidth.

Abstract: A frequency detection technique includes generating first and second signals such that a frequency of the first signal is the same as a frequency of the second signal and such that the second signal is phase-shifted by a fixed amount with respect to the first signal. The technique further includes generating a third signal having a frequency that corresponds to an absolute value of a difference between the frequency of the first signal and an integer multiple of a frequency of the reference signal. The technique further includes generating a fourth signal having a frequency that corresponds to an absolute value of a difference between the frequency of the second signal and an integer multiple of the frequency of the reference signal. The technique further includes generating an fifth signal indicative of whether a phase relationship between the third and fourth signals is a leading phase relationship, a lagging phase relationship, or an in-phase relationship.

Abstract: A tunable quadrature oscillator includes a first oscillator having an output, a second oscillator having an output, and a variable gain amplifier. The variable gain amplifier includes an input coupled to the output of the second oscillator, and an output inductively coupled to the output of the first oscillator.

Abstract: A system and method for tracking noise in a received signal uses a forward/backward Decision-Directed Phase Tracking Loop to generate a phase-noise compensation signal that removes phase noise from received single-carrier signals.

Abstract: Conventional routers employ a wired backplane that employs “long reach” serializer/deserializer (SerDes) links, but this type of architecture is complicated, costly, and uses a considerable amount of power. To address some of these issues, a new wireless backplane architecture is provided here. This wireless backplane employs direct millimeter wave links between line cards that replaces the convention, wired switching fabric.