Abstract: An optical coupling system for coupling a light source to a photonic integrated circuit (PIC) comprises a multimode coupler configured to receive an input optical signal of a first mode. The multimode coupler triggers one or more higher-order modes from the input optical signal of the first mode. The optical coupling system also includes a mode de-multiplexer and an optical combiner. The mode de-multiplexer transfers the input optical signal of the first mode and one or more optical signals of the triggered one or more higher-order modes to respective output optical signals of the first mode. The optical combiner combines the respective output optical signals to produce a single output signal of the first mode.

Abstract: Example polarization splitter and rotator devices are described. In one example, an optical apparatus includes a splitter configured to split a light signal into a first signal having a first polarization and a second signal having a second polarization, a polarization rotator configured to rotate the second polarization of the second signal into a third polarization, and a polarization mode converter configured to convert the third polarization of the second signal into the first polarization. In certain aspects of the embodiments, the splitter can be a curved multi-mode inference (MMI) polarization splitter, and the polarization rotator comprises input and output ports, with the output port being wider than the input port. The polarization mode converter can be an asymmetrical waveguide taper mode converter. The devices described herein can overcome the deficiencies of conventional devices and provide low insertion loss, flat and/or wide wavelength response, high fabrication tolerance, and compact size.

Abstract: An optical coupling system for coupling a light source to a photonic integrated circuit (PIC) comprises a multimode coupler configured to receive an input optical signal of a first mode. The multimode coupler triggers one or more higher-order modes from the input optical signal of the first mode. The optical coupling system also includes a mode de-multiplexer and an optical combiner. The mode de-multiplexer transfers the input optical signal of the first mode and one or more optical signals of the triggered one or more higher-order modes to respective output optical signals of the first mode. The optical combiner combines the respective output optical signals to produce a single output signal of the first mode.

Abstract: Example polarization splitter and rotator devices are described. In one example, an optical apparatus includes a splitter configured to split a light signal into a first signal having a first polarization and a second signal having a second polarization, a polarization rotator configured to rotate the second polarization of the second signal into a third polarization, and a polarization mode converter configured to convert the third polarization of the second signal into the first polarization. In certain aspects of the embodiments, the splitter can be a curved multi-mode inference (MMI) polarization splitter, and the polarization rotator comprises input and output ports, with the output port being wider than the input port. The polarization mode converter can be an asymmetrical waveguide taper mode converter. The devices described herein can overcome the deficiencies of conventional devices and provide low insertion loss, flat and/or wide wavelength response, high fabrication tolerance, and compact size.

Abstract: Example polarization splitter and rotator devices are described. In one example, an optical apparatus includes a splitter configured to split a light signal into a first signal having a first polarization and a second signal having a second polarization, a polarization rotator configured to rotate the second polarization of the second signal into a third polarization, and a polarization mode converter configured to convert the third polarization of the second signal into the first polarization. In certain aspects of the embodiments, the splitter can be a curved multi-mode inference (MMI) polarization splitter, and the polarization rotator comprises input and output ports, with the output port being wider than the input port. The polarization mode converter can be an asymmetrical waveguide taper mode converter. The devices described herein can overcome the deficiencies of conventional devices and provide low insertion loss, flat and/or wide wavelength response, high fabrication tolerance, and compact size.

Abstract: Example polarization splitter and rotator devices are described. In one example, an optical apparatus includes a splitter configured to split a light signal into a first signal having a first polarization and a second signal having a second polarization, a polarization rotator configured to rotate the second polarization of the second signal into a third polarization, and a polarization mode converter configured to convert the third polarization of the second signal into the first polarization. In certain aspects of the embodiments, the splitter can be a curved multi-mode inference (MMI) polarization splitter, and the polarization rotator comprises input and output ports, with the output port being wider than the input port. The polarization mode converter can be an asymmetrical waveguide taper mode converter. The devices described herein can overcome the deficiencies of conventional devices and provide low insertion loss, flat and/or wide wavelength response, high fabrication tolerance, and compact size.

Abstract: A system for correcting duty cycle errors in a clock receiver that includes a differential amplifier having inputs for a pair of differential clock signals. A duty cycle error detector has inputs for a pair of amplified clock signals and an output for a duty cycle error correction signal. A signal conditioner is also provided with the differential amplifier having an input for the duty cycle error correction signal. Furthermore, the signal conditioner adjusts the differential clock signals in response to the duty cycle error correction signal. Also, a system for correcting cross point errors in a clock receiver that includes a differential amplifier having inputs for a pair of differential clock signal. A cross point error detector has inputs for a pair of amplified clock signals and an output for a cross point error correction signal. A signal conditioner is also provided with the differential amplifier having an input for the cross point error correction signal.

Abstract: A method for generating a data signal for synchronizing one or more electrically coupled digital receivers is disclosed. A data signal having a data rate is modulated with a pseudo-noise (PN) code having a data rate greater than the data rate of the data signal. The modulated data signal is demodulated by a receiver using the PN code. A correlation value is generated and is compared to a predetermined value to indicate phase synchronization. If the receiver is in phase synchronization with the transmitter, the received demodulated data signal is passed.

Abstract: A system for correcting duty cycle errors in a clock receiver that includes a differential amplifier having inputs for a pair of differential clock signals. A duty cycle error detector has inputs for a pair of amplified clock signals and an output for a duty cycle error correction signal. A signal conditioner is also provided with the differential amplifier having an input for the duty cycle error correction signal. Furthermore, the signal conditioner adjusts the differential clock signals in response to the duty cycle error correction signal. Also, a system for correcting cross point errors in a clock receiver that includes a differential amplifier having inputs for a pair of differential clock signal. A cross point error detector has inputs for a pair of amplified clock signals and an output for a cross point error correction signal. A signal conditioner is also provided with the differential amplifier having an input for the cross point error correction signal.

Abstract: An electronic chip has a data input for receiving an input digital data signal with a data frequency, a plurality of switches, and a logic circuit operatively coupled with both the plurality of switches and the data input. The logic circuit controls the switches to be in one of a DAC mode or a mixer mode. The DAC mode causes the switches to convert the input digital data signal into a DAC analog signal having about the data frequency. The mixer mode, however, causes the switches to convert the input digital data signal into a mixed analog signal having a mixer frequency that is higher than the data frequency.

Abstract: An electronic chip has a data input for receiving an input digital data signal with a data frequency, a plurality of switches, and a logic circuit operatively coupled with both the plurality of switches and the data input. The logic circuit controls the switches to be in one of a DAC mode or a mixer mode. The DAC mode causes the switches to convert the input digital data signal into a DAC analog signal having about the data frequency. The mixer mode, however, causes the switches to convert the input digital data signal into a mixed analog signal having a mixer frequency that is higher than the data frequency.

Abstract: A method for generating a data signal for synchronizing one or more electrically coupled digital receivers is disclosed. A data signal having a data rate is modulated with a pseudo-noise (PN) code having a data rate greater than the data rate of the data signal. The modulated data signal is demodulated by a receiver using the PN code. A correlation value is generated and is compared to a predetermined value to indicate phase synchronization. If the receiver is in phase synchronization with the transmitter, the received demodulated data signal is passed.

Abstract: A system and method for oversampling and modulating a digital data stream. A programmable quadrature interpolating filter is provided which allows the passband of the output signal to be selected from a set of mode selections. The set of mode selections provide overlapping passbands spanning the Nyquist range of the filter. The filter allows a signal to be shifted to a desired carrier frequency before the signal is oversampled and filtered, reducing power consumption in devices such as digital-to-analog converters.