Nxp B.v.

St-Ericsson Sa

Mihai A T Sanduleanu

Eduard Ferdinand Stikvoort

Ram P Aditham

Gerben Willem De Jong

Jan Sophia Vromans

The present invention relates to a polar modulation apparatus and method, in which a polar-modulated signal is generated based on separately processed phase modulation (PM) and amplitude modulation (AM) components of an input signal. An amplified polar modulated output signal is generated in accordance with the phase modulation and amplitude modulation components by using a differential power amplifier circuitry() and supplying an amplified phase modulation component to a differential input of the differential power amplifier circuitry(). A bias input of the differential power amplifier circuitry() is controlled based on the amplitude modulation component, so as to modulate a common-mode current of the differential power amplifier circuitry(). Thereby, a new concept of a polar modulator with static DC-DC converter and power and/or efficiency and/or linearity controlled output power amplifier can be achieved.

Polar modulation apparatus and method with common-mode control

The present invention relates to an oscillator circuit and a method of controlling the oscillation frequency of an in-phase signal and a quadrature signal. First oscillator means () with a first differential oscillator circuit and a first differential coupling circuit are provided for generating the quadrature signal. Furthermore, second oscillator means () with a second differential oscillator circuit and a second differential coupling circuit are provided for generating the in-phase signal. A frequency control means is provided for varying the oscillation frequency of the in-phase signal and the quadrature signal by controlling at least one of a common-mode current and a tail current of the first and second oscillator means. Thereby, a high-frequency IQ oscillator with high linearity is obtained.

Quadrature oscillator with high linearity

The present invention relates to a polar modulation apparatus and method, in which a polar-modulated signal is generated based on separately processed phase modulation (PM) and amplitude modulation (AM) components of an input signal. An amplified polar modulated output signal is generated in accordance with the phase modulation and amplitude modulation components by using a differential power amplifier circuitry and supplying an amplified phase modulation component to a differential input of the differential power amplifier circuitry. A bias input of the differential power amplifier circuitry is controlled based on the amplitude modulation component, so as to modulate a common-mode current of the differential power amplifier circuitry. Thereby, a new concept of a polar modulator with static DC-DC converter and power and/or efficiency and/or linearity controlled output power amplifier can be achieved.

The present invention relates in general to transferring the envelope information of a polar modulated signal to a varying pulsewidth signal, while the phase modulation is direct transferred to the phase modulation of this PWM signal. Accordingly, the resultant signal is a PWM-PPM-signal. Such a signal can efficiently amplified by use of switching amplifying stages. By the present invention four pre-distorted baseband signals are applied basically to 4 linear RF mixers and a two adders, which are, the only needed external RF building blocks to build the modulator according to the invention. That is, the basic idea of the invention resides in the way of modulation of the four baseband signals and the way of combining of the RF modulated signals.

Radio frequency PWM & PPM modulator

A BALUN circuit () for low voltage operation for receiving single ended input signal at an input terminal () and providing a differential output signal across a pair of output terminals (OUT+, OUT&#x2212;) is disclosed. The BALUN circuit () comprises a first branch including an input terminal () for receiving a single ended input voltage signal (RFin), a transistor (Q), a resistance (R) (), a resistance (RL), and an output terminal (OUT+). A second branch includes a transistor (Q), a resistance (RL) and an output terminal (OUT&#x2212;). An operational amplifier () maintains current flowing through the resistances RL in the first and second branches substantially equal to each other, in dependence upon the output voltage signal across the output terminals (OUT+, OUT&#x2212;).

Transformer circuit

A sub-harmonic mixer circuit having an input stage () and a current modulating stage (is disclosed. The input stage () receives an RF input signal (RF+, RF&#x2212;) at a first frequency and generates output currents (il , i) varying in dependence upon the Rf input signal. The current modulating stage () comprises a first transistor (Q) for receiving a first local oscillator signal (LO) respective and a second transistor (Q) for receiving a second local oscillator signal (LO), 180 degrees out of phase with the first local oscillator signal, such that a modulating current signal (iO), having twice the local oscillator frequency is superimposed onto the output currents.

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Maastricht, Netherlands

Mihai A T Sanduleanu