Abstract: An on-chip calibration system comprises a transmitter, a receiver, a phase and amplitude determination element configured to determine amplitude and phase characteristics of an output signal generated in the transmitter, the signal representing transmitter characteristics, an amplitude comparison element configured to compare the signal representing transmitter characteristics with a desired amplitude signal and generate an amplitude compensation signal, an AM predistortion element configured to modify an ideal AM signal with the amplitude compensation signal, a phase comparison element configured to compare the signal representing transmitter characteristics with a desired phase signal and generate a phase compensation signal, and a PM predistortion element configured to modify an ideal phase signal with the phase compensation signal.

Abstract: A radio frequency (RF) receiver device comprises a receiver system that receives an analog radio frequency signal and downconverts the analog radio frequency signal to a downconverted analog signal, the receiver system further including a peak signal detector configured to determine a peak signal level of the downconverted analog signal, and an automatic gain control adjustment element configured to determine whether the peak signal level falls within a predetermined range, and configured to generate, in the RF receiver, a gain control signal controlling the gain of at least one analog component based on whether the peak signal level falls within the predetermined range.

Abstract: Embodiments of a receiver impairment estimation and correction system and method that can be implemented in a low intermediate frequency receiver system are disclosed. In one embodiment, among others, a method for operating a receiver is disclosed that comprises receiving a radio frequency signal, downconverting the radio frequency signal to a downconverted signal comprising an in-phase component and quadrature-phase component, buffering the downconverted signal in a memory, estimating receiver impairments associated with the in-phase component and the quadrature-phase component for a defined time period, and compensating for the receiver impairments for each defined time period.

Abstract: An internal calibration system for a radio frequency (RF) transmitter comprises a digital processing element to generate within a radio frequency (RF) transmitter test points at which an output of the RF transmitter is measured, an RF detector to measure the radio frequency output of the RF transmitter at the test points, the digital processing element also determining transmitter impairments by analyzing the measured radio frequency output, and compensation circuitry to compensate the RF transmitter for the measured impairments.

Abstract: A transmit-receive switch architecture comprises a first switch coupled to transmit circuitry and to an antenna, a second switch coupled to receive circuitry and to ground, wherein the second switch is configured to couple the receive circuitry to ground during a time period in which a power source associated with the transmit circuitry is enabled.

Abstract: Embodiments of a low intermediate frequency system and method are disclosed. In one embodiment, among others, a method for operating a receiver is disclosed that comprises receiving a radio frequency signal, downconverting the radio frequency signal to a downconverted signal comprising an in-phase component and quadrature component, and estimating a gain and phase imbalance between the in-phase component and the quadrature component.

Abstract: An adaptive band-pass filter for a wireless receiver comprises a band-pass filter associated with the receiver, the band-pass filter configured to selectively filter the received signal, and a switch responsive to a control signal, the switch configured to control the band-pass filter based on a level of the received signal.

Abstract: A system for transmitting and receiving data is provided. The system includes a direct-conversion receiver that receives a signal modulated on a carrier frequency signal. The direct-conversion receiver includes one or more subharmonic local oscillator mixers. A local oscillator is connected to the direct conversion receiver, and generates a signal having a frequency equal to a subharmonic of the carrier frequency signal. A transmitter is connected to the local oscillator, which uses the local oscillator signal to transmit outgoing data.

Abstract: A method for a closed power control feedback loop allows a single portable transceiver architecture to be used for systems in which a transmit signal including both a phase modulated (PM) component and an amplitude modulated (AM) component are supplied to a power amplifier and in systems in which the transmit signal has only a PM component supplied to a power amplifier. By injecting the inverse of the AM portion of the desired transmit signal into the closed power control feedback loop, the feedback loop will not cancel the AM portion of the signal, thus allowing a system where both a PM component and an AM component of the transmit signal are present at the output of the power amplifier to function using a closed power control feedback loop.