108 results about "Polar transmitter" patented technology

Certain aspects of a method and system for a wideband polar transmitter may be disclosed. Aspects of the method may include polar modulating a plurality of signals by generating a plurality of modulated intermediate frequency (IF) signals corresponding to each of a plurality of wireless communication protocols within a transmitter that handles the plurality of wireless communication protocols. The generated plurality of modulated IF signals may be upconverted to a plurality of radio frequency (RF) signals. The plurality of RF signals may be combined and the combined plurality of RF signals may be amplitude modulated.

A power amplifier controller controls a power amplifier and is coupled to a polar modulator. The polar modulator generates an amplitude component and a phase-modulated component of the desired RF modulated signal, and outputs to the power amplifier controller. The power amplifier controller regenerates a combined phase and amplitude modulated RF signal to generate an input signal to a power amplifier by adjusting the gain of a VGA based on the amplitude component of the desired RF modulated signal. Concurrently, the power amplifier controller both controls an adjusted supply voltage to the PA and adjusts the gain of the VGA based upon an amplitude correction signal or amplitude error signal.

An output-power threshold is selected such that one or more signal requirements is not outside a pre-determined range when output power of a polar transmitter is less than the output-power threshold. A determination is made whether the output power is less than the threshold. In response to a determination that the output power is less than the threshold, amplitude modulation of a polar signal transmitted by the polar transmitter is disabled. When the output power meets or exceeds the output-power threshold, the polar signal transmitted by the polar transmitter is both amplitude and phase modulated.

A test signal comprising a periodic waveform, such as a triangular waveform and sawtooth waveform, is used for propagation delay matching in a transceiver front-end. The test signal is separately fed to the envelope path and the RF path. At the power amplifier stage, a phase modulator is used to obtain the envelope signal and the phase modulated RF signal for demodulation by an IQ demodulator. At the output end of the IQ demodulator, the I-signal is measured while the delay block is adjusted in order to vary the propagation delay. When the propagation delay matching is correct, the peak-to-peak value of the I-signal is a minimum. Preferably, during calibration using the test signal, the transmitter RF power amplifier is disabled so that no spurious signals will be sent. The transmitter can be an EDGE polar transmitter, a non-EDGE transmitter or a EER polar transmitter.

Systems and methods are disclosed for providing a linear polar transmitter. The systems and methods may include generating an input amplitude signal and an input phase signal, where the input amplitude signal and the input phase signal are orthogonal components of an input signal, and where the input amplitude signal and the input phase signal are generated on respective first and second signal paths. The systems and methods may also include processing the input amplitude signal along the first signal path using an amplitude error signal to generate a predistorted amplitude signal, and processing the input phase signal along the second signal path using an phase error signal to generate a predistorted phase signal. The systems and methods may also include providing the predistorted amplitude signal along the first signal path and the predistorted phase signal along the second signal path to a power amplifier to generate an output signal, where the amplitude error signal is generated from a comparison of at least an amplitude portion of the output signal with the predistorted amplitude signal and where the phase error signal is generated from a comparison of at least a phase portion of the output signal with the predistorted phase signal.

A polar transmitter, operable in linear mode or switched mode, uses a conversion module to convert baseband signals into amplitude data and phase data. The phase data is used to phase modulate a carrier frequency in a radio frequency conversion module. The module comprises a plurality of parallel unit cells, each being a mixer cell type converter having a differential data switch section connected in series to a differential local oscillator-switch pair. The differential local oscillator-switch is connected in series to a current source. Each unit cell is adapted to receive a signal through an input end. In switched mode, the phase-modulated carrier frequency is amplitude modulated by the amplitude data through the supply voltage to a power amplifier. In linear mode, amplitude data is conveyed to the input end of the unit cells for modulating the phase-modulated carrier frequency in the conversion module.

A novel apparatus for and method of delay alignment between amplitude and phase / frequency modulation paths in a digital polar transmitter. The invention provides a fully digital delay alignment mechanism where better than nanosecond alignment is achieved by accounting for processing delays in the digital circuit modules of the transmitter and by the use of programmable delay elements spread across several clock domains. Tapped delay lines compensate for propagation and settling delays in analog elements such as the DCO, dividers, quad switch, buffers, level shifters and digital pre-power amplifier (DPA). A signal correlative mechanism is provided whereby data from the amplitude and phase / frequency modulation paths to be matched is first interpolated and then cross-correlated to achieve accuracy better than the clock domain of comparison. Within the ADPLL portion of the transmitter, precise alignment of reference and direct point injection points in the ADPLL is provded using multiple clock domains, tapped delay lines and clock adjustment circuits.

A test signal comprising a periodic waveform, such as a triangular waveform and sawtooth waveform, is used for propagation delay matching in a transceiver front-end. The test signal is separately fed to the envelope path and the RF path. At the power amplifier stage, a phase modulator is used to obtain the envelope signal and the phase modulated RF signal for demodulation by an IQ demodulator. At the output end of the IQ demodulator, the I-signal is measured while the delay block is adjusted in order to vary the propagation delay. When the propagation delay matching is correct, the peak-to-peak value of the I-signal is a minimum. Preferably, during calibration using the test signal, the transmitter RF power amplifier is disabled so that no spurious signals will be sent. The transmitter can be an EDGE polar transmitter, a non-EDGE transmitter or a EER polar transmitter.

A polar transmitter includes a power amplifier (PA), an amplitude modulation (AM) path including an AM path adjustable delay, an AM path delay measurement circuit, a phase modulation (PM) path including a PM path adjustable delay, and a PM path delay measurement circuit. The AM path delay measurement circuit is configured to measure an AM path delay using waveform correlation, e.g., using peak magnitude events (PMEs) in signals transmitted along the AM path to a power supply port of the PA. The PM path delay measurement circuit is configured to measure a PM path delay using waveform correlation, e.g., using PMEs in signals transmitted along the PM path to a phase-modulated input of the PA. The measured AM and PM path delays are used to adjust the AM and PM path adjustable delays, to reduce the delay mismatch between signals appearing at the power supply and phase-modulated input ports of the polar transmitter's PA.