Abstract: Systems and methods are provided for generating dual outputs in a digital exciter system. A first signal path produces one of a frequency modulated audio signal, a digital information signal, and a signal comprising both frequency modulated audio and digital information. A second signal path produces one of a frequency modulated audio signal, a digital information signal, and a signal comprising both frequency modulated audio and digital information. A main exciter output provides one of the signal produced at the first signal path and the signal produced at the second signal path to an associated first signal destination.

Abstract: Systems and methods are provided for amplifying a composite input signal, comprising a drive signal and an envelope signal, at a power amplifier. A secondary modulation, representing a portion of the composite input signal falling outside of a frequency band associated with the envelope signal, is produced for the drive signal. The secondary modulation is applied to the drive signal. The drive signal is amplified at the power amplifier to produce an amplified signal. At least a portion of the envelope signal is employed to drive a supply terminal of the power amplifier.

Abstract: Systems and methods are provided for efficient amplification of a signal utilizing a modified Doherty amplifier system. A modified Doherty amplifier system includes a nonlinear main amplifier and a nonlinear auxiliary amplifier. An impedance-inverting network separates the main amplifier from an associated load. A second quarter wave transmission line separates the auxiliary amplifier from an associated signal source. The signal source has an associated minimum signal power, such that the signal power never drops below a predetermined percentage of a peak signal power.

Abstract: Systems and methods are provided for providing a hybrid signal having a reduced crest factor. An analog exciter generates an analog signal having an associated phase. A digital exciter generates a digital signal that assumes one of a plurality of vector states at discrete sampling times associated with the hybrid signal. Each of the plurality of vector states has an associated phase. The digital signal and the analog signal are combined to provide the hybrid signal. The hybrid signal is compressed maximally when the digital signal assumes a vector state that is in phase with the analog signal.

Abstract: An RF wideband amplifier system is provided that includes an M way splitter for receiving an RF input signal and splitting same into M RF signals for respective application to M power amplifier modules PAM-1 to PAM-M that amplify the M signals and apply the amplified M signals to an M way combiner that applies an amplified RF signal to a load. A main controller provides an automatic level control reference signal, representative of the desired output power level of each of the power amplifier modules.

Abstract: A directional coupler comprises a coupler circuit board which is mounted substantially perpendicular to the surface of a parent circuit board. First and second upper traces are disposed on the opposing surfaces of the coupler circuit board. The coupling between the upper electrically conductive traces determines the odd mode impedance of the coupler. First and second lower traces are also disposed on opposing surfaces and connected to ground. The upper and lower traces are arranged such that the even mode of the impedance is determined by the coupling between the first upper trace and the second lower trace and the coupling between the second upper trace and the first lower trace.

Abstract: An RF wideband amplifier system is provided that includes an M way splitter for receiving an RF input signal and splitting same into M RF signals for respective application to M power amplifier modules PAM-1 to PAM-M that amplify the M signals and apply the amplified M signals to an M way combiner that applies an amplified RF signal to a load. A main controller provides an automatic level control reference signal, representative of the desired output power level of each of the power amplifier modules.

Abstract: A directional coupler comprises a coupler circuit board which is mounted substantially perpendicular to the surface of a parent circuit board. First and second upper traces are disposed on the opposing surfaces of the coupler circuit board. The coupling between the upper electrically conductive traces determines the odd mode impedance of the coupler. First and second lower traces are also disposed on opposing surfaces and connected to ground. The upper and lower traces are arranged such that the even mode of the impedance is determined by the coupling between the first upper trace and the second lower trace and the coupling between the second upper trace and the first lower trace.

Abstract: A power amplifier system is presented for use in amplifying an RF input signal comprising N sub-power amplifiers are connected together in parallel with each receiving and amplifying a portion of the RF input signal. A combiner combines the amplified portions of the RF input signal to provide a combined output signal. Each sub-amplifier includes at least one transistor having an input port that receives a DC bias voltage and an output port, such that when the RF input signal is not present a quiescent current flows through the output port. A controller is operative when the RF signal is not present to check and adjust the magnitude of the quiescent current flowing in each of the sub-amplifier output ports in the sequence of 1 . . . N.