A first resistor connected in parallel to a semiconductor optical modulator having first ends, the first resistor and first ends connected to a reference potential. A first end of a first transmission line is connected to second ends of the semiconductor optical modulator and the first resistor. A second transmission line is connected in series to the first transmission line and has an impedance lower than that of the first resistor. A first end of the second transmission line is connected to a second end of the first transmission line. A third transmission line is connected in series to the first and second transmission lines and has an end connected to a second end of the second transmission line, and has an impedance equal to that of the first transmission line. A second resistor and a capacitor are connected in series between the third transmission line and the reference potential.

The present disclosure relates in general to devices, systems and methods for wireless communication, and in particular to communication using a proximity integrated circuit card (PICC). Example embodiments include a circuit (100) for a PICC, the circuit comprising an input stage (101), a decoding module (106) and a bias adjustment module (117), the bias adjustment module (117) configured to receive an output code from the decoding module and provide a bias adjustment signal to the input stage (101), the bias adjustment module (117) configured to iteratively tune the bias adjustment signal based on a measurement of the output code, with successive steps tuning the bias adjustment signal by a smaller amount until the output code is within a decoding range.

Embodiments of the present disclosure utilizes the natural properties of RFI noise on a wireline link. Since differential RFI noise in the system has some correlation with the common mode noise on the cable, a replica of RFI noise can be regenerated by an adaptive filter based on information about the common mode noise. The replica RFI is subtracted from the equalizer output prior to the data decision circuitry or slicer. In this method, the system does not require expensive cable, nor does the equalizer suffer additional loss due to an RFI notch filter. Since RFI can be detected and mitigated, this information can also be coupled to safety systems to increase functional safety under high EMI conditions.

Embodiments of the present disclosure utilizes the natural properties of RFI noise on a wireline link. Since differential RFI noise in the system has some correlation with the common mode noise on the cable, a replica of RFI noise can be regenerated by an adaptive filter based on information about the common mode noise. The replica RFI is subtracted from the equalizer output prior to the data decision circuitry or slicer. In this method, the system does not require expensive cable, nor does the equalizer suffer additional loss due to an RFI notch filter. Since RFI can be detected and mitigated, this information can also be coupled to safety systems to increase functional safety under high EMI conditions.

There is provided a main unit and a distributed antenna system including the same. The main unit for constituting a distributed antenna system that receives a base station signal from at least one base station, transmits the base station signal to at least one user terminal, and includes a plurality of main units, the main unit includes: a first receiver for receiving a first group of base station signals; a second receiver for receiving a second group of base station signals from another main unit; a signal combiner for combining the first and second groups of base station signals; and a delay compensator for compensating for time delay corresponding to a path between the main unit and the other main unit with respect to the first group of base station signals before combining the first and second groups of base station signals.

There is provided a main unit and a distributed antenna system including the same. The main unit for constituting a distributed antenna system that receives a base station signal from at least one base station, transmits the base station signal to at least one user terminal, and includes a plurality of main units, the main unit includes: a first receiver for receiving a first group of base station signals; a second receiver for receiving a second group of base station signals from another main unit; a signal combiner for combining the first and second groups of base station signals; and a delay compensator for compensating for time delay corresponding to a path between the main unit and the other main unit with respect to the first group of base station signals before combining the first and second groups of base station signals.

The present disclosure provides a pre-equalization compensation method and device for a link, a storage medium and an electronic device. The method includes: in response to that an Active Antenna Unit (AAU) is powered on, parsing a prestored off-line compensation table to obtain first non-flatness equalization coefficients of an RF link with a plurality of sub-carriers and second non-flatness equalization coefficients of a wave control link with the plurality of sub-carriers, with each one of the plurality of sub-carriers corresponding to one of the first non-flatness equalization coefficients and one of the second non-flatness equalization coefficients; combining the first non-flatness equalization coefficients of the plurality of sub-carriers and the second non-flatness equalization coefficients of the plurality of sub-carriers to obtain a combined carrier non-flatness coefficient; and performing equalization compensation on the link according to the combined carrier non-flatness coefficient.

The present disclosure provides a pre-equalization compensation method and device for a link, a storage medium and an electronic device. The method includes: in response to that an Active Antenna Unit (AAU) is powered on, parsing a prestored off-line compensation table to obtain first non-flatness equalization coefficients of an RF link with a plurality of sub-carriers and second non-flatness equalization coefficients of a wave control link with the plurality of sub-carriers, with each one of the plurality of sub-carriers corresponding to one of the first non-flatness equalization coefficients and one of the second non-flatness equalization coefficients; combining the first non-flatness equalization coefficients of the plurality of sub-carriers and the second non-flatness equalization coefficients of the plurality of sub-carriers to obtain a combined carrier non-flatness coefficient; and performing equalization compensation on the link according to the combined carrier non-flatness coefficient.

The present disclosure provides a pre-equalization compensation method and device for a link, a storage medium and an electronic device. The method includes: in response to that an Active Antenna Unit (AAU) is powered on, parsing a prestored off-line compensation table to obtain first non-flatness equalization coefficients of an RF link with a plurality of sub-carriers and second non-flatness equalization coefficients of a wave control link with the plurality of sub-carriers, with each one of the plurality of sub-carriers corresponding to one of the first non-flatness equalization coefficients and one of the second non-flatness equalization coefficients; combining the first non-flatness equalization coefficients of the plurality of sub-carriers and the second non-flatness equalization coefficients of the plurality of sub-carriers to obtain a combined carrier non-flatness coefficient; and performing equalization compensation on the link according to the combined carrier non-flatness coefficient.

The present disclosure provides a pre-equalization compensation method and device for a link, a storage medium and an electronic device. The method includes: in response to that an Active Antenna Unit (AAU) is powered on, parsing a prestored off-line compensation table to obtain first non-flatness equalization coefficients of an RF link with a plurality of sub-carriers and second non-flatness equalization coefficients of a wave control link with the plurality of sub-carriers, with each one of the plurality of sub-carriers corresponding to one of the first non-flatness equalization coefficients and one of the second non-flatness equalization coefficients; combining the first non-flatness equalization coefficients of the plurality of sub-carriers and the second non-flatness equalization coefficients of the plurality of sub-carriers to obtain a combined carrier non-flatness coefficient; and performing equalization compensation on the link according to the combined carrier non-flatness coefficient.