Abstract: A filter for a micropulse differential absorption LIDAR is provided. The filter comprises an etalon including a free spectral range substantially the same as a difference between a first laser wavelength and a second laser wavelength, the etalon further including a finesse providing substantial background noise suppression and substantially constant transmission of the first laser wavelength and the second laser wavelength over a predetermined range of wavelengths, and a first filter having a first filter bandpass selected to include the first laser wavelength and the second laser wavelength.

Abstract: A shared optics and telescope, a filter, and a micropulse differential absorption LIDAR are provided, with methods to use the same. The shared optics and telescope includes a pair of axicon lenses, a secondary mirror, a primary mirror including an inner mirror portion and an outer mirror portion, the inner mirror portion operable to expand the deflected annular transmission beam, and the outer mirror portion operable to collect the return signal. The filter includes an etalon and a first filter. The micropulse differential absorption LIDAR includes first and second laser signals, a laser transmission beam selection switch, a first laser return signal switch, and a toggle timer.

Abstract: Systems, methods, and devices of the present invention use a single Pseudo Noise (PN) code to modulate multiple orthogonal carriers by Binary Phase Shift Keying (BPSK) modulation. The various embodiments enable closely spaced carriers to be modulated with the same periodic PN sequence using BPSK modulation. In this manner, even though the carriers may almost entirely share bandwidth, orthogonality of the carriers may not be lost, enabling the various embodiments to be used with limited bandwidth Intensity Modulated Continuous Wave (IM-CW) Light detection and ranging (Lidar), Radio detection and ranging (Radar), or Sound Navigation and Ranging (Sonar) systems. Additionally, by using orthogonal carriers the various embodiments enable measurements to be made simultaneously, thereby reducing the error compared to systems that require sequential measurements, such as pulsed Lidar systems.

Abstract: Systems, methods, and devices may enhance the apparent sample rate of data collected using Nyquist sampling from a system, such as Continuous Wave (CW) Light detection and ranging (“Lidar”), Radio detection and ranging (“Radar”), or Sound Navigation and Ranging (“Sonar”), that has been modulated with a repeating waveform, such as linear swept frequency, by reordering of the data in the frequency domain. The enhancement of the apparent sample rate may result in a highly interpolated range profile where the data resolution may be enhanced by a factor equal to the number of repeats in the signal being processed, and may result in a highly detained range measurement with a high precision. The various embodiments may combine data from multiple modulation repeats into a single highly interpolated pulse, which may result in a real-time finer range measurement from CW Lidar, Radar, or Sonar systems.

Abstract: A filter for a micropulse differential absorption LIDAR is provided. The filter comprises an etalon including a free spectral range substantially the same as a difference between a first laser wavelength and a second laser wavelength, the etalon further including a finesse providing substantial background noise suppression and substantially constant transmission of the first laser wavelength and the second laser wavelength over a predetermined range of wavelengths, and a first filter having a first filter bandpass selected to include the first laser wavelength and the second laser wavelength.

Abstract: A shared optics and telescope, a filter, and a micropulse differential absorption LIDAR are provided, with methods to use the same. The shared optics and telescope includes a pair of axicon lenses, a secondary mirror, a primary mirror including an inner mirror portion and an outer mirror portion, the inner mirror portion operable to expand the deflected annular transmission beam, and the outer mirror portion operable to collect the return signal. The filter includes an etalon and a first filter. The micropulse differential absorption LIDAR includes first and second laser signals, a laser transmission beam selection switch, a first laser return signal switch, and a toggle timer.

Abstract: Systems, methods, and devices of the present invention use a single Pseudo Noise (PN) code to modulate multiple orthogonal carriers by Binary Phase Shift Keying (BPSK) modulation. The various embodiments enable closely spaced carriers to be modulated with the same periodic PN sequence using BPSK modulation. In this manner, even though the carriers may almost entirely share bandwidth, orthogonality of the carriers may not be lost, enabling the various embodiments to be used with limited bandwidth Intensity Modulated Continuous Wave (IM-CW) Light detection and ranging (Lidar), Radio detection and ranging (Radar), or Sound Navigation and Ranging (Sonar) systems. Additionally, by using orthogonal carriers the various embodiments enable measurements to be made simultaneously, thereby reducing the error compared to systems that require sequential measurements, such as pulsed Lidar systems.

Abstract: Systems, methods, and devices may enhance the apparent sample rate of data collected using Nyquist sampling from a system, such as Continuous Wave (CW) Light detection and ranging (“Lidar”), Radio detection and ranging (“Radar”), or Sound Navigation and Ranging (“Sonar”), that has been modulated with a repeating waveform, such as linear swept frequency, by reordering of the data in the frequency domain. The enhancement of the apparent sample rate may result in a highly interpolated range profile where the data resolution may be enhanced by a factor equal to the number of repeats in the signal being processed, and may result in a highly detained range measurement with a high precision. The various embodiments may combine data from multiple modulation repeats into a single highly interpolated pulse, which may result in a real-time finer range measurement from CW Lidar, Radar, or Sonar systems.

Abstract: A continuous wave Light Detection and Ranging (CW LiDAR) system utilizes two or more laser frequencies and time or range shifted pseudorandom noise (PN) codes to discriminate between the laser frequencies. The performance of these codes can be improved by subtracting out the bias before processing. The CW LiDAR system may be mounted to an artificial satellite orbiting the earth, and the relative strength of the return signal for each frequency can be utilized to determine the concentration of selected gases or other substances in the atmosphere.