The present technology relates to a notch filter capable of easily obtaining a desired frequency characteristic. In an N-path filter unit, any one of a plurality of N capacitors is selected as a signal path through which a signal passes, so that the capacitor serving as the signal path is temporally switched. A plurality of N-path filter units is cascade-connected and a capacitor is inserted to a connection point between the N-path filter units. The present technology may be applied to the notch filter which eliminates a blocker and the like, for example.

The disclosure relates to a method for operating a selective switching device for signals, a related selective switching device, and a message transmission system having the selective switching device. An embodiment of the method includes the following steps, not necessarily in this order: determining a current temperature in the region of the selective switching device; determining a signal shift of the selective switching device due to the current temperature; adding the signal shift to an input signal of the selective switching device as to receive a compensated signal for which the signal shift due to the current temperature is compensated; and removing the signal shift from an output signal of the selective switching device as to receive a corrected signal for which the compensation is corrected.

A frequency conversion device, intended for installation on board a satellite, comprises an active assembly comprising at least one first radiofrequency processing chain comprising a first mixer, a first local oscillator operating at a first frequency and linked to the first mixer, at least one second radiofrequency processing chain comprising a second mixer, and a second local oscillator operating at a second frequency and linked to the second mixer and a current or voltage converter for supplying power to the active assembly.

Mechanisms for interferer detection can detect interferers by detecting elevated signal amplitudes in one or more of a plurality of bins (or bands) in a frequency range between a maximum frequency (f.sub.MAX) and a minimum frequency (f.sub.MIN). To perform rapid interferer detection, the mechanisms downconvert an input signal x(t) with a local oscillator (LO) to a complex baseband signal xI(t)+jxQ(t). xI(t) and xQ(t) are then multiplied by m unique pseudorandom noise (PN) sequences (e.g., Gold sequences) gm(t) to produce m branch signals for I and m branch signals for Q. The branch signals are then low pass filtered, converted from analog to digital form, and pairwise combined by a pairwise complex combiner. Finally, a support recovery function is used to identify interferers.

There is provided a communication device including a first transmitter configured to up-convert a frequency of a first transmission signal to a first frequency so as to be wirelessly transmitted, a second transmitter configured to up-convert a frequency of a second transmission signal to a second frequency different from the first frequency so as to be wirelessly transmitted, a receiver configured to receive a reception signal including a passive intermodulation signal generated due to the first and second transmission signals wirelessly transmitted, a memory, and a processor coupled to the memory and configured to estimate frequency errors of the up-converted first and second transmission signals, generate a cancellation signal into which any frequency of the first and second transmission signals has been corrected, based on the estimated frequency errors, and combine the cancellation signal with a down-converted reception signal.

According to an embodiment of the inventive concept, an up-down converter includes a first mixer configured to convert an input radio frequency (RF) signal into an intermediate frequency (IF) signal using a first local signal; an IF filter configured to filter the IF signal converted by the first mixer; a second mixer configured to convert the IF signal, which has been filtered by the IF filter, into an output RF signal using a second local signal; and a local oscillator configured to control a frequency of the first local signal and the second local signal based on a frequency of the input RF signal.

A frequency conversion device, intended for installation on board a satellite, comprises an active assembly comprising at least one first radiofrequency processing chain comprising a first mixer, a first local oscillator operating at a first frequency and linked to the first mixer, at least one second radiofrequency processing chain comprising a second mixer, and a second local oscillator operating at a second frequency and linked to the second mixer and a current or voltage converter for supplying power to the active assembly.

A signal frequency conversion circuit is configured to reduce power consumption and resource costs of the signal frequency conversion circuit. Embodiments of the present disclosure include a primary-stage frequency conversion module and at least one subsequent-stage frequency conversion module that is in series connection, where the primary-stage frequency conversion module includes a first filter and a numerically controlled oscillator NCO, and an output of the first filter is connected to an input of the NCO; each subsequent-stage frequency conversion module includes a second filter and a subsequent-stage frequency conversion unit, and an output of the second filter is connected to an input of the subsequent-stage frequency conversion unit; and an output of the NCO is connected to an input of a second filter in a first subsequent-stage frequency conversion module in the at least one subsequent-stage frequency conversion module in series connection.

The disclosure relates to a method for operating a selective switching device for signals, a related selective switching device, and a message transmission system having the selective switching device. An embodiment of the method includes the following steps, not necessarily in this order: determining a current temperature in the region of the selective switching device; determining a signal shift of the selective switching device due to the current temperature; adding the signal shift to an input signal of the selective switching device as to receive a compensated signal for which the signal shift due to the current temperature is compensated; and removing the signal shift from an output signal of the selective switching device as to receive a corrected signal for which the compensation is corrected.

A wide tuning range receiver is provided that includes first and second mixers, and first and second local oscillators. The first mixer can mix an input signal with a signal from the first local oscillator and output a signal having a first intermediate frequency, the second mixer can mix the signal having the first intermediate frequency with a signal from the second local oscillator and output a signal having a second intermediate frequency, and, for each input signal frequency, a relationship between the first and second local oscillators can be fixed.