Abstract: Structure and design methods of electrical power amplifiers suitable for broadband application such as television frequency or white spaces. An example broadband power amplifier passes a transmit carrier with modulations from BPSK to 256 QAM, on channel bandwidths from 6 to 32 MHz, over the entire UHF television band from 470 to 800 MHz using a low voltage, low power, narrowband power amplifier transistor. Based on a push-pull technique to lower the impedance level thus improving the match and doubling the power, the wide-band power amplification is performed with a balanced polynomial filter transform structure wherein the circuit impedance increases sequentially within the filter stage. The polynomial filtering makes high selectivity of out-of-band signals thereby cleaning up harmonic signals which prevent the need for additional high selective radio frequency filters. The invented power amplifier enables efficient broadband power amplifiers having a form factor within 300 square millimeters of space.

Abstract: Structure and design methods of electrical power amplifiers suitable for broadband application such as television frequency or white spaces. An example broadband power amplifier passes a transmit carrier with modulations from BPSK to 256 QAM, on channel bandwidths from 6 to 32 MHz, over the entire UHF television band from 470 to 800 MHz using a low voltage, low power, narrowband power amplifier transistor. Based on a push-pull technique to lower the impedance level thus improving the match and doubling the power, the wide-band power amplification is performed with a balanced polynomial filter transform structure wherein the circuit impedance increases sequentially within the filter stage. The polynomial filtering makes high selectivity of out-of-band signals thereby cleaning up harmonic signals which prevent the need for additional high selective radio frequency filters. The invented power amplifier enables efficient broadband power amplifiers having a form factor within 300 square millimeters of space.

Abstract: A single tone RF signal generator and a method of generating a single tone RF signal. The single tone RF signal generator includes an output and a power amplifier that has an input. The power amplifier is operable to receive an RF signal including a first harmonic corresponding to a single tone signal to be produced by the signal generator. The power amplifier is also operable to amplify the RF signal. The power amplifier is further operable to provide the amplified RF signal to the output of the signal generator. The single tone RF signal generator further includes a feedback circuit connected between the output of the signal generator and the input of the power amplifier. The feedback circuit is configured to add one or more predistortion harmonics to the RF signal received by the power amplifier for cancelling harmonics in the amplified RF signal provided by the power amplifier.

Abstract: A single tone RF signal generator and a method of generating a single tone RF signal. The single tone RF signal generator includes an output and a power amplifier that has an input. The power amplifier is operable to receive an RF signal including a first harmonic corresponding to a single tone signal to be produced by the signal generator. The power amplifier is also operable to amplify the RF signal. The power amplifier is further operable to provide the amplified RF signal to the output of the signal generator. The single tone RF signal generator further includes a feedback circuit connected between the output of the signal generator and the input of the power amplifier. The feedback circuit is configured to add one or more predistortion harmonics to the RF signal received by the power amplifier for cancelling harmonics in the amplified RF signal provided by the power amplifier.

Abstract: An adaptive stepped gain amplifier, for example for use in broadband receivers, has a step size which is dynamically compensated (for each received frequency) to cope with step error caused by frequency dependence of the amplifier performance.

Abstract: An adaptive stepped gain amplifier, for example for use in broadband receivers, has a step size which is dynamically compensated (for each received frequency) to cope with step error caused by frequency dependence of the amplifier performance.

Abstract: A system and method provide adaptive filtering of radio frequency (RF) signals. Multiple signals are received in a predetermined RF spectrum, the signals including a desired signal and multiple potentially interfering signals. A first signal of the potentially interfering signals is down-converted to a baseband signal, and a power of the baseband signal is determined. When the power exceeds a predetermined threshold power, a first notch filter, corresponding to a frequency of the first signal, is activated.

Abstract: A harmonic rejection mixer unit is provided which comprises an input (RF), at least one harmonic rejection unit (HRU) with at least two transistor units (T3a, T3b; T4a, T4b) for multiplying an input signal from the input (RF) with a multiplication signal (ELO). The harmonic rejection mixer unit furthermore comprises a transistor control signal generating unit (GGU) for generating transistor control signals (GS1-GS4) for the at least two transistor units (T3a, T3b; T4a, T4b) of the at least one harmonic rejection unit (HRU) by deriving the transistor control signals (GS1-GS4) from a local oscillator signal (LO). The transistor control signals (GS3, GS4) for the at least two transistor units (T3a, T3b; T4a, T4b) are generated with a duty cycle of <50% and are generated such that the shape of the multiplication signal ELO) is achieved by a constructive summation of the output signals from the transistor units (T3a, T3b; T4a, T4b).

Abstract: A method and circuit for signal processing in a receiver that can be tuned to different carriers, the method determining the energy of the adjacent carriers N+1 and N?1, wherein a carrier N contains a signal of interest and the receiver is tuned to it, from the digital signal, in that the energy value of the carriers N+1 and N?1 determined are compared with a threshold value, and in the case where the threshold value is exceeded, a frequency shift of the signal by +?f or ??f is effected in the second method step prior to the filtering, and the frequency shift thus produced is reversed by a frequency shift by ??f or +?f prior to the filtering, and the signal is decoded.

Abstract: A system and method provide adaptive filtering of radio frequency (RF) signals. Multiple signals are received in a predetermined RF spectrum, the signals including a desired signal and multiple potentially interfering signals. A first signal of the potentially interfering signals is down-converted to a baseband signal, and a power of the baseband signal is determined. When the power exceeds a predetermined threshold power, a first notch filter, corresponding to a frequency of the first signal, is activated.

Abstract: A harmonic rejection mixer unit is provided which comprises an input (RF), at least one harmonic rejection unit (HRU) with at least two transistor units (T3a, T3b; T4a, T4b) for multiplying an input signal from the input (RF) with a multiplication signal (ELO). The harmonic rejection mixer unit furthermore comprises a transistor control signal generating unit (GGU) for generating transistor control signals (GS1-GS4) for the at least two transistor units (T3a, T3b; T4a, T4b) of the at least one harmonic rejection unit (HRU) by deriving the transistor control signals (GS1-GS4) from a local oscillator signal (LO). The transistor control signals (GS3, GS4) for the at least two transistor units (T3a, T3b; T4a, T4b) are generated with a duty cycle of <50% and are generated such that the shape of the multiplication signal ELO) is achieved by a constructive summation of the output signals from the transistor units (T3a, T3b; T4a, T4b).

Abstract: A controllable-gain circuit (TI, Rt, TS1, . . . , TS4) provides a first and a second pair of complementary gain-controlled signals (Ip1, Ip3; Ip2, Ip4) in response to an input signal (RFI). In each pair, one gain-controlled signal (Ip1, Ip2) is the input signal amplified with a gain G comprised in a range between a minimum gain Gmin and a maximum gain Gmax. The other gain-controlled signal (Ip3, Ip4) is the input signal amplified with complementary gain Gmax-G. A fixed-gain output circuit (Rfg, Nfg) makes a weighed sum (Ip1*Rfg+Ip3*Rfg) of one and the other gain-controlled signal in the first pair of complementary gain-controlled signals. The respective weighing factors for one and the other gain-controlled signal are substantially similar (Rfg). A controllable-gain output circuit (Rlg, Rhg, Nlg, Nhg) makes a weighed sum (Ip2*Rlg+Ip4*(Rlg+Rhg)) of one and the other gaincontrolled signal in the second pair of complementary gain-controlled signals.

Abstract: A method and circuit for signal processing in a receiver that can be tuned to different carriers, the method determining the energy of the adjacent carriers N+1 and N?1, wherein a carrier N contains a signal of interest and the receiver is tuned to it, from the digital signal, in that the energy value of the carriers N+1 and N?1 determined are compared with a threshold value, and in the case where the threshold value is exceeded, a frequency shift of the signal by +?f or ??f is effected in the second method step prior to the filtering, and the frequency shift thus produced is reversed by a frequency shift by ??f or +?f prior to the filtering, and the signal is decoded.

Abstract: A controllable-gain circuit (TI, Rt, TS1, . . . , TS4) provides a first and a second pair of complementary gain-controlled signals (Ip1, Ip3; Ip2, Ip4) in response to an input signal (RFI). In each pair, one gain-controlled signal (Ip1, Ip2) is the input signal amplified with a gain G comprised in a range between a minimum gain Gmin and a maximum gain Gmax. The other gain-controlled signal (Ip3, Ip4) is the input signal amplified with complementary gain Gmax-G. A fixed-gain output circuit (Rfg, Nfg) makes a weighed sum (Ip1*Rfg+Ip3*Rfg) of one and the other gain-controlled signal in the first pair of complementary gain-controlled signals. The respective weighing factors for one and the other gain-controlled signal are substantially similar (Rfg). A controllable-gain output circuit (Rlg, Rhg, Nlg, Nhg) makes a weighed sum (Ip2*Rlg+Ip4*(Rlg+Rhg)) of one and the other gaincontrolled signal in the second pair of complementary gain-controlled signals.

Abstract: The invention relates to a tuner for converting a RF signal (110) into an IF output signal (202), said tuner comprising a mixer (111) for generating a first IF signal (201), processing means (114) for filtering said first IF signal (201) so as to generate said IF output signal (202).

Abstract: The invention relates to an electronic apparatus comprising at least one transistor having a control terminal and an intrinsic capacitance junction with a variable value as a function of the temperature, said transistor being associated with a compensation device for compensating the effects of the variation of said intrinsic capacitance junction. To this end, the electronic apparatus is characterized in that said compensation device comprises a combination of means behaving as a variable capacitance, said variable capacitance having such a variation as a function of the temperature that it compensates said effects, said variable capacitance being connected to said intrinsic capacitance.

Abstract: The present invention relates to a circuit intended to generate a negative conductance NG between two connection terminals A and B, including a first and a second transistor T1 and T2 connected as a differential pair between said connection terminals A and B.