Abstract: An integrated radio frequency terminal system includes an integrated modem configured to receive user data and communicate user data to and from a user device. The integrated modem includes a transmit tuner configured to receive the user data and convert the user data from baseband to an intermediate frequency band. The integrated modem includes a receive tuner connected to the baseband modem device and configured to convert received incoming data in the intermediate frequency band to baseband and provide the converted incoming data to the baseband modem device. The system includes a power amplifier connected to the integrated modem and configured to convert the user data from the intermediate frequency band to a radio frequency band. The system includes a low noise amplifier connected to the integrated modem and configured to convert received incoming data from the radio frequency band to the intermediate frequency band.

Abstract: An integrated radio frequency terminal system includes an integrated modem configured to receive user data and communicate user data to and from a user device. The integrated modem includes a transmit tuner configured to receive the user data and convert the user data from baseband to an intermediate frequency band. The integrated modem includes a receive tuner connected to the baseband modem device and configured to convert received incoming data in the intermediate frequency band to baseband and provide the converted incoming data to the baseband modem device. The system includes a power amplifier connected to the integrated modem and configured to convert the user data from the intermediate frequency band to a radio frequency band. The system includes a low noise amplifier connected to the integrated modem and configured to convert received incoming data from the radio frequency band to the intermediate frequency band.

Abstract: A tunable filter for adjustable filtering between a minimum frequency and a maximum frequency includes a transmission line designed to transmit a signal and having longitudinal axis. The tunable filter further includes a two-dimensional capacitor array including step-tunable capacitors located along the transmission line, a first dimension of the two-dimensional capacitor array being along the longitudinal axis and a second dimension of the two-dimensional capacitor array being located perpendicular to the longitudinal axis. The tunable filter further includes a controller coupled to each of the step-tunable capacitors and designed to control each of the step-tunable capacitors independently to be in a biased mode or in an unbiased mode based on a desired frequency response of the tunable filter.

Abstract: Methods and systems for detecting objects in a three-dimensional space. The method includes emitting, by a plurality of transmitters oriented in a respective plurality of directions, signals to produce uniform millimeter wave illumination of the three-dimensional space. The method includes determining object data including a direction, a phase, and a timing of signals reflected from one or more objects within the three-dimensional space. The method includes detecting, by a processor, the one or more objects in the three-dimensional space based on the object data. The method includes rendering, by the processor, an image corresponding to the one or more detected objects.

Abstract: An integrated radio frequency terminal system includes an integrated modem configured to receive user data and communicate user data to and from a user device. The integrated modem includes a transmit tuner configured to receive the user data and convert the user data from baseband to an intermediate frequency band. The integrated modem includes a receive tuner connected to the baseband modem device and configured to convert received incoming data in the intermediate frequency band to baseband and provide the converted incoming data to the baseband modem device. The system includes a power amplifier connected to the integrated modem and configured to convert the user data from the intermediate frequency band to a radio frequency band. The system includes a low noise amplifier connected to the integrated modem and configured to convert received incoming data from the radio frequency band to the intermediate frequency band.

Abstract: An integrated radio frequency terminal system includes an integrated modem configured to receive user data and communicate user data to and from a user device. The integrated modem includes a transmit tuner configured to receive the user data and convert the user data from baseband to an intermediate frequency band. The integrated modem includes a receive tuner connected to the baseband modem device and configured to convert received incoming data in the intermediate frequency band to baseband and provide the converted incoming data to the baseband modem device. The system includes a power amplifier connected to the integrated modem and configured to convert the user data from the intermediate frequency band to a radio frequency band. The system includes a low noise amplifier connected to the integrated modem and configured to convert received incoming data from the radio frequency band to the intermediate frequency band.

Abstract: A tunable filter for adjustable filtering between a minimum frequency and a maximum frequency includes a transmission line designed to transmit a signal and having longitudinal axis. The tunable filter further includes a two-dimensional capacitor array including step-tunable capacitors located along the transmission line, a first dimension of the two-dimensional capacitor array being along the longitudinal axis and a second dimension of the two-dimensional capacitor array being located perpendicular to the longitudinal axis. The tunable filter further includes a controller coupled to each of the step-tunable capacitors and designed to control each of the step-tunable capacitors independently to be in a biased mode or in an unbiased mode based on a desired frequency response of the tunable filter.

Abstract: A microcontroller-based controller executes interleaved DC bias and gain control routines using monitored values of the monitored photocurrent output signal of a Mach-Zehnder laser modulator to derive a gain setting for the modulation drive signal and a bias level setting for the DC bias level, without tuning or adjustment. Subsequent to convergence of the gain and bias level settings, the control unit may repetitively interrupt and restart the DC bias and gain control routine at intervals that are staggered in a random time fashion, to achieve spectral dispersion of the gain and bias level settings, and provide insensitivity to periodic environmental noise.

Abstract: A single reference tone/frequency-based control scheme adjusts the DC bias voltage and modulation signal drive level to an external X-cut lithium niobate Mach Zehnder modulator, in accordance with phase quadrature components of the output of the single tone frequency generator. A pair of phase quadrature feedback loops are coupled through a loop filter of a common feedback path electo-optically coupled to monitor the optical output of the laser modulator. Quadrature-phase (Q) and in-phase (I) frequency components are respectively coupled to respective Q and I channel phase detectors, coupled to synchronous demodulators for the Q and I channel feedback loops. The phase detectors produce respective error voltages that close Q and I channel feedback loops and control the optical extinction ratio and DC bias voltage of the modulator.

Abstract: A dual pulse width modulated driver controls the operation of a thermo-electric cooler for stabilizing the operating temperature of a laser. The pulse width modulator has complementary outputs coupled to control inputs of dual pairs of complementary polarity electronic switching elements, that are coupled in circuit between first and second power supply terminals, and a pair of output nodes. The output nodes are coupled in common through a low pass filters to drive terminals of a thermoelectric cooling element. The thermal output generated by the thermoelectric cooling element is coupled to the laser. The thermal output of the cooling element is monitored by a temperature sensing element mounted with the laser and provides an output voltage in linear proportion of its thermal input. This output voltage is fed back through a temperature control servo loop to a differential summing circuit, which is also coupled to receive a reference voltage used to control the duty cycle of the pulse width modulator.

Abstract: A microcontroller-based controller executes interleaved DC bias and gain control routines using monitored values of the monitored photocurrent output signal of a Mach-Zehnder laser modulator to derive a gain setting for the modulation drive signal and a bias level setting for the DC bias level, without tuning or adjustment. Subsequent to convergence of the gain and bias level settings, the control unit may repetitively interrupt and restart the DC bias and gain control routine at intervals that are staggered in a random time fashion, to achieve spectral dispersion of the gain and bias level settings, and provide insensitivity to periodic environmental noise.

Abstract: Constant envelope angle modulation apparatus comprises a frequency synthesizer for outputting a stepped output waveform having a selectable precise output frequency. The output of the synthesizer provides an input to a mixer for O-QPSK modulating a received information signal. The O-QPSK modulated signal is then hard-limited, for example, via a series of hard limiting amplifier and filter circuits and a divider circuit. Preferably, a data stream for modulation may be filtered via a filter having an approximately 70-100% roll-off characteristic, such as a root raised cosine filter. A hard-limited, constant envelope angle modulated signal results that is easily frequency converted to, for example, microwave frequencies for landline or satellite applications via a simple multiplier circuit. The multiplier circuit preferably comprises a series of stage-filtered multipliers and band pass filters to achieve the desired output microwave frequency.