Abstract: Various embodiments relate to a method and circuit for combining channels, the method including receiving, by a matching and smoothing filter, a signal from an analog to digital converter and extracting a root mean square signal level, receiving, by a noise power detector (“NPD”), the signal from the ADC and assessing noise contribution on the signal and receiving, by a maximum ratio combiner, the signal from the matching and smoothing filter wherein a combiner selects between using a geometric sum and an arithmetic sum to combine the channels.

Abstract: Embodiments are provided for a method of operating a receiver system, the receiver system comprising one or more channels, the method comprising: monitoring a residual DC (direct current) offset in a present channel by sampling an output of an analog-to-digital converter (ADC) of the present channel; adjusting a DCO (direct current offset) correction signal that corresponds to the residual DC offset in response to an absolute value of the residual DC offset exceeding a programmable DCO threshold; and subtracting the DCO correction signal from an analog signal provided to the ADC to reduce the residual DC offset below the programmable DCO threshold.

Abstract: A contactless communication device includes a receiver unit having differential input terminals for connecting to an antenna. The receiver unit is coupled to a transmitting device and receives an RF signal transmitted by the transmitting device. A first comparator is adapted to generate a first comparator output signal indicative of a relationship between a voltage at a positive input terminal of the receiver unit and a first reference voltage. A second comparator is adapted to generate a second comparator output signal indicative of a relationship between a voltage at a negative input terminal of the receiver unit and a second reference voltage. A first voltage regulation circuit is adapted to regulate the voltage at the positive input terminal in response to the first comparator output signal. A second voltage regulation circuit is adapted to regulate the voltage at the negative input terminal in response to the second comparator output signal.

Abstract: Various embodiments relate to a method and circuit for combining channels, the method including receiving, by a matching and smoothing filter, a signal from an analog to digital converter and extracting a root mean square signal level, receiving, by a noise power detector (“NPD”), the signal from the ADC and assessing noise contribution on the signal and receiving, by a maximum ratio combiner, the signal from the matching and smoothing filter wherein a combiner selects between using a geometric sum and an arithmetic sum to combine the channels.

Abstract: A contactless communication device includes a receiver unit having differential input terminals for connecting to an antenna. The receiver unit is coupled to a transmitting device and receives an RF signal transmitted by the transmitting device. A first comparator is adapted to generate a first comparator output signal indicative of a relationship between a voltage at a positive input terminal of the receiver unit and a first reference voltage. A second comparator is adapted to generate a second comparator output signal indicative of a relationship between a voltage at a negative input terminal of the receiver unit and a second reference voltage. A first voltage regulation circuit is adapted to regulate the voltage at the positive input terminal in response to the first comparator output signal. A second voltage regulation circuit is adapted to regulate the voltage at the negative input terminal in response to the second comparator output signal.

Abstract: Embodiments of a method and a system controlling an amplifier of a communications device are disclosed. In an embodiment, a method for controlling an amplifier of a communications device involves checking for a data reception at the communications device and freezing a gain of the amplifier if the data reception is detected.

Abstract: Various embodiments relate to a method and apparatus for over sampling a RF carrier signal, the method including receiving, by an ADC, the RF carrier signal, sampling, by the ADC, the RF carrier signal using the selected clock signal which is at least quadruple the RF carrier signal, down sampling, by a RF-DSP, the RF carrier signal by a factor of two to generate I channel data and Q channel data, mixing down, by the RF-DSP, the I channel data and the Q channel data, and outputting, by the RF-DSP, the I channel data and Q channel data to a baseband DSP.

Abstract: Various embodiments relate to a method and apparatus for over sampling a RF carrier signal, the method including receiving, by an ADC, the RF carrier signal, sampling, by the ADC, the RF carrier signal using the selected clock signal which is at least quadruple the RF carrier signal, down sampling, by a RF-DSP, the RF carrier signal by a factor of two to generate I channel data and Q channel data, mixing down, by the RF-DSP, the I channel data and the Q channel data, and outputting, by the RF-DSP, the I channel data and Q channel data to a baseband DSP.

Abstract: There is described a contactless communication device. The device comprises (a) a receiver unit (110, 610) having an antenna input (RXn, Vmid, RXp) for connecting to an antenna, the receiver unit (110, 610) being adapted to couple with a transmitting device and to receive an RF signal transmitted by the transmitting device, the receiver unit (110, 610) being further adapted to determine a point of time relating to a position of data within the RF signal, (b) a comparator (120) adapted to generate a comparator output signal (agc_comp) which is indicative of a relation between a voltage at the antenna input (RXn, Vmid, RXp) of the receiver unit (110, 610) and a reference voltage (Vref), and (c) a voltage regulation circuit coupled to the comparator (120) and to the antenna input (RXn, Vmid, RXp) of the receiver unit (110, 610), the voltage regulation circuit being adapted to repetitively regulate the voltage at the antenna input (RXn, Vmid, RXp) based on the comparator output signal (agc_comp).

Abstract: Various embodiments relate to a method and apparatus for a method for under sampling a RF carrier signal, the method including receiving, by an analog digital converter, the RF carrier signal, selecting, by a multiplexer, a clock signal which includes a first clock signal and a second clock signal which are phase shifted, receiving, by the ADC, the clock signal which has a frequency less that the frequency of the RF carrier signal, sampling, by the ADC, the RF carrier signal using the selected clock signal and demodulating, by a digital signal processor, the RF carrier signal into I channel data and Q channel data for I/Q demodulation.

Abstract: Apparatus for clock synchronization comprising a first phase locked loop (405) and a second phase locked loop (400). The first phase locked loop (405) is configured to receive a reference signal (Fcrystal) having a reference frequency, and operable to produce an output signal (Fout) having an output frequency that is a multiple of the reference frequency. The first phase locked loop (405) comprises a frequency divider (428) that controls the multiple in response to a control signal. The second phase locked loop (400) is configured to determine a phase error between the output signal (Fout) and an input signal (Fantenna), and to provide the control signal to the first phase locked loop (405). The second phase locked loop (400) comprises phase adjustment means (450), operable to adjust a phase difference between the input and output signal by varying the control signal for a duration.

Abstract: Embodiments of a method and a system for generating a received signal strength indicator (RSSI) value that corresponds to a radio frequency (RF) signal are disclosed. In an embodiment, a method for generating an RSSI value that corresponds to an RF signal involves obtaining an attenuation factor code in response to applying an automatic gain control (AGC) operation to the RF signal, obtaining an analog-to-digital converter (ADC) code in response to applying an ADC operation to a signal that results from the AGC operation, and combining the attenuation factor code and the ADC code to generate an RSSI value. Other embodiments are also described.

Abstract: Embodiments of a method and a system for processing a radio frequency (RF) signal are disclosed. In an embodiment, a method for processing an RF signal involves down-converting the RF signal into a converted signal, obtaining a received signal strength indicator (RSSI) value based on an amplitude of the RF signal, and amplifying the converted signal based on the RSSI value.

Abstract: Embodiments of a method and a system for generating a received signal strength indicator (RSSI) value that corresponds to a radio frequency (RF) signal are disclosed. In an embodiment, a method for generating an RSSI value that corresponds to an RF signal involves obtaining an attenuation factor code in response to applying an automatic gain control (AGC) operation to the RF signal, obtaining an analog-to-digital converter (ADC) code in response to applying an ADC operation to a signal that results from the AGC operation, and combining the attenuation factor code and the ADC code to generate an RSSI value. Other embodiments are also described.

Abstract: Embodiments of a method and a system for processing a radio frequency (RF) signal are disclosed. In an embodiment, a method for processing an RF signal involves down-converting the RF signal into a converted signal, obtaining a received signal strength indicator (RSSI) value based on an amplitude of the RF signal, and amplifying the converted signal based on the RSSI value.

Abstract: Embodiments of a method and a system controlling an amplifier of a communications device are disclosed. In an embodiment, a method for controlling an amplifier of a communications device involves checking for a data reception at the communications device and freezing a gain of the amplifier if the data reception is detected.

Abstract: Transients caused by load modulation can fee compensated far by adjusting pulse shapes. A radio frequency (RP) carrier signal can be modulated using load modulation. For the modulated RF carrier signal a particular pattern can be detected for a symbol period that precedes a second symbol that does not use load modulation. In response to the detecting, a pulse shape of the first symbol can be adjusted to mitigate the transients.

Abstract: Transients caused by load modulation can fee compensated far by adjusting pulse shapes. A radio frequency (RP) carrier signal can be modulated using load modulation. For the modulated RF carrier signal a particular pattern can be detected for a symbol period that precedes a second symbol that does not use load modulation. In response to the detecting, a pulse shape of the first symbol can be adjusted to mitigate the transients.

Abstract: Apparatus for clock synchronisation comprising a first phase locked loop (405) and a second phase locked loop (400). The first phase locked loop (405) is configured to receive a reference signal (Fcrystal) having a reference frequency, and operable to produce an output signal (Fout) having an output frequency that is a multiple of the reference frequency. The first phase locked loop (405) comprises a frequency divider (428) that controls the multiple in response to a control signal. The second phase locked loop (400) is configured to determine a phase error between the output signal (Fout) and an input signal (Fantenna), and to provide the control signal to the first phase locked loop (405). The second phase locked loop (400) comprises phase adjustment means (450), operable to adjust a phase difference between the input and output signal by varying the control signal for a duration.

Abstract: There is described an RF bidirectional communication device utilizing active load modulation, the device comprising (a) a resonance circuit including an antenna (326), and (b) a control unit (322) for controlling communication of the device, including switching between a transmission mode and a receiving mode, wherein the control unit is adapted to (c) modify a configuration of the resonance circuit such that the resonance circuit has a first resonance frequency (f0) when the device is in the transmission mode and a second resonance frequency (f0+?f) when the device is in the receiving mode, and (d) modify the configuration of the resonance circuit such that a Q-factor of the resonance circuit is periodically decreased while the device is in the transmission mode. There is also described a corresponding method and a system comprising a RF device and a reader/writer device. Furthermore, there is described a computer program and a computer program product.