Abstract: A differential amplifier for amplifying an input differential signal having two components (In+, In?) substantially in anti-phase to each other and generating an output differential signal having two differential components (Out+, Out?). The amplifier comprises a pair of inverters coupled to a pair of adders the inverters receiving the input differential signal. The amplifier is characterized in that it further comprises a pair of controllable buffers for receiving the input differential signal and outputting a signal to the pair of adders. A bias of the said pair of buffers is cross-controlled by the input differential signal for controlling an amplification of said pair of controllable buffers.

Abstract: A receiver comprising an input for receiving a first signal, said receiver further comprising a local oscillator for generating a periodical signal. The receiver further comprises a mixer for generating a third signal representative for a combination of a second signal and the periodical signal. The receiver is characterized in that it further comprises a voltage to current converter for receiving the first signal and generating the second signal as a current indicative for the first signal. The mixer comprises a plurality of controllable switches. The receiver further comprises a variable gain current to voltage converter (VGIV) coupled to the passive mixer, the VGIV receiving the third signal and generating a first voltage signal, said first voltage signal being in a linear relationship with the third signal.

Abstract: A communication system comprising a power amplifier coupled to a detector and further coupled to a Bias generator. The detector comprises a controlled amplifier means for generating an output signal (Th_S), the said signal Th_S being indicative for the power of an input signal and having a controllable bias level. The Bias Generator comprises a Level Sensitive Current Generator (LSCG) for generating a current (Cc) controlled by the output signal Th_S. Said LSCG has a threshold level (TL) such that when the output Th_S signal is lower than the TL the current Cc is substantially zero. Otherwise the current Cc is linearly controlled by the signal Th_S. The Bias Generator further comprises an adapter coupled to the LSCG comprising a current controlled adapting means for generating a control signal (C_S) for controlling a property of the amplifier, the control signal C_S having a controllable linear dependency on the current Cc.

Abstract: A communication system comprising a power amplifier coupled to a detector and further coupled to a Bias generator. The detector comprises a controlled amplifier means for generating an output signal (Th_S), the said signal Th_S being indicative for the power of an input signal and having a controllable bias level. The Bias Generator comprises a Level Sensitive Current Generator (LSCG) for generating a current (Cc) controlled by the output signal Th_S. Said LSCG has a threshold level (TL) such that when the output Th_S signal is lower than the TL the current Cc is substantially zero. Otherwise the current Cc is linearly controlled by the signal Th_S. The Bias Generator further comprises an adapter coupled to the LSCG comprising a current controlled adapting means for generating a control signal (C_S) for controlling a property of the amplifier, the control signal C_S having a controllable linear dependency on the current Cc.

Abstract: A filter (3) is described, which filter is provided with field effect (FET) capacitors (M1-32; M′1-32) arranged for controlling their respective capacity values, each such FET capacitor (M1-32; M′1-32) having a source (S) and a drain (D). The source (S) and the drain (D) of each FET capacitor (M1-32; M′1-32) are coupled to one another. The filter acting as an impedance transformer is a passive low power consuming and tunable filter, such as for a radio frequency (RF) receiver. It occupies only a very small area, while integrated on chip.

Abstract: A quadrature coupled controlled oscillator comprising a first and a second circuit module, each of the circuit modules (100 and 100′) comprising an astable multivibrator circuit (103). The first circuit module is coupled with the second circuit module and the second circuit module is cross coupled with the first circuit module. Each of the circuit modules (100 and 100′) comprises a first and a second Voltage Controlled Current Source (101) (VCCS). In each of the circuit modules, each VCCS is coupled to a phase shifter (102) for shifting the phase of a current (110) supplied by the VCCS to a resonator (104) included in that circuit module. A communication arrangement (300) for communicating via a bi-directional communication channel (304), comprises an oscillator (303) as described above for generating a periodic signal. A receiving module (301) generates an output signal from the periodic signal and a receiving signal received from the channel (304).

Abstract: The invention relates to a method for modulating an output voltage of a transmitter circuit comprising a voltage controlled oscillator, a digital/analog converter and an antenna circuit, the method comprising the method comprising sending an output signal of sufficient power from the voltage controlled oscillator directly to the antenna circuit and directly modulating a frequency of the output signal of the voltage controlled oscillator. The invention furthermore relates to a transmitter circuit comprising a voltage controlled oscillator having a tank circuit, a digital/analog converter and an antenna circuit, wherein the voltage controlled oscillator is adapted to send an output signal of sufficient power directly to the antenna circuit and wherein the digital/analog converter is arranged to modulate an output frequency of the voltage controlled oscillator.

Abstract: An amplifier, in particular an RF amplifier is described having an amplifier input, the amplifier comprises: a first controllable semiconductor having a first controllable mainstream path coupled to first source means for controlling the first mainstream path, and having a first biased control input; and a second controllable semiconductor having a second controllable mainstream path coupled to second source means for controlling the second mainstream path, and having a second control input coupled to the first main stream path and to the amplifier input. Both the first and second mainstream paths are coupled to a common load, and the first and second source means are arranged for controlling input impedance and noise impedance respectively of the amplifier input. This amplifier arrangement allows independent control and optimisation of both the amplifier input impedance and the noise impedance.

Abstract: A receiver comprising an input for receiving a first signal, said receiver further comprising a local oscillator for generating a periodical signal. The receiver further comprises a mixer for generating a third signal representative for a combination of a second signal and the periodical signal. The receiver is characterized in that it further comprises a voltage to current converter for receiving the first signal and generating the second signal as a current indicative for the first signal. The mixer comprises a plurality of controllable switches. The receiver further comprises a variable gain current to voltage converter (VGIV) coupled to the passive mixer, the VGIV receiving the third signal and generating a first voltage signal, said first voltage signal being in a linear relationship with the third signal.

Abstract: The invention relates to a method for modulating an output voltage of a transmitter circuit comprising a voltage controlled oscillator, a digital/analog converter and an antenna circuit, the method comprising the method comprising sending an output signal of sufficient power from the voltage controlled oscillator directly to the antenna circuit and directly modulating a frequency of the output signal of the voltage controlled oscillator. The invention furthermore relates to a transmitter circuit comprising a voltage controlled oscillator having a tank circuit, a digital/analog converter and an antenna circuit, wherein the voltage controlled oscillator is adapted to send an output signal of sufficient power directly to the antenna circuit and wherein the digital/analog converter is arranged to modulate an output frequency of the voltage controlled oscillator.

Abstract: A quadrature coupled controlled oscillator comprising a first and a second circuit modules, each of the circuit modules (100 and 100′) comprising an astable multivibrator circuit (103), the first circuit module (100) being coupled with the second circuit module (100′) and the second circuit module (100′) being cross coupled with the first circuit module (100), each of the circuit modules (100 and 100′) comprising a first and a second Voltage Controlled Current Source (101) (VCCS).

Abstract: A filter (3) is described, which filter is provided with field effect (FET) capacitors (M1-32; M′1-32) arranged for controlling their respective capacity values, each such FET capacitor (M1-32; M′1-32) having a source (S) and a drain (D). The source (S) and the drain (D) of each FET capacitor (M1-32; M′1-32) are coupled to one another. The filter acting as an impedance transformer is a passive low power consuming and tunable filter, such as for a radio frequency (RF) receiver. It occupies only a very small area, while integrated on chip.

Abstract: A front end and a high frequency receiver (1) provided therewith are described, which front end comprises a quadrature low noise amplifier (2-1, 2-2) as a low noise amplifier. A high isolation between local oscillators (6-1, 6-2) and quadrature mixers (3-1, 3-2) is achieved thereby, reducing a DC offset at mixer outputs (7, 8). The quadrature low noise amplifier may be implemented as a differential class AB cascode arrangement of MOST or FET semiconductors (15). A low distortion receiver (1) having a high linearity is the result.

Abstract: An amplifier, in particular an RF amplifier is described having an amplifier input, the amplifier comprises: a first controllable semiconductor having a first controllable mainstream path coupled to first source means for controlling the first mainstream path, and having a first biased control input; and a second controllable semiconductor having a second controllable mainstream path coupled to second source means for controlling the second mainstream path, and having a second control input coupled to the first main stream path and to the amplifier input. Both the first and second mainstream paths are coupled to a common load, and the first and second source means are arranged for controlling input impedance and noise impedance respectively of the amplifier input. This amplifier arrangement allows independent control and optimisation of both the amplifier input impedance and the noise impedance.