Abstract: The present disclosure includes a system and method for adjusting parameters associated with leakage signals. In some implementations, an RFID reader includes an RF antenna, a transmitter section, a receiver section, a control module and a cancellation noise reduction (CNR) section. The transmitter section is coupled to the RF antenna and operable to generate a transmit signal to be transmitted by the RF antenna. The receiver section is coupled to the RF antenna and operable to receive a receive signal from the RF antenna. In addition, the receiver section further includes a de-rotation module and a control module. The de-rotation module is operable to de-rotate, by ?, an in-phase signal and quadrature signal associated with the leakage signal. The control module is operable to generate control signals used to produce a signal for reducing the leakage signal in a receive path of the reader. The CNR section is operable to subtract from the reduction signal from the leakage signal.

Abstract: The disclosure includes a system and method for oversampling and digitally filtering RFID signals. In some implementations of the present disclosure, an RF receiver includes an ADC, a comb filter, and a mask filter. The ADC is operable to directly sample an RF signal independent of a band pass filter and convert the RF signal to a digital signal. The RF signal is sampled at a rate greater than or equal to 60 MHz. The comb filter is coupled to the ADC. The mask filter is coupled to the comb filter. The comb filter and frequency mask filter are configured to filter out-of-band noise in the digital signal.

Abstract: The present disclosure includes a system and method for reducing leakage noise in directly sampled radio frequency signals. In some implementations, a Radio Frequency IDentification (RFID) reader includes an antenna, an Analog-to-Digital Converter (ADC), a synthesizer module, and a Carrier Noise Reduction (CNR) module. The antenna is configured to receive Radio Frequency (RF) signals and pass the RF signals to a receive path. The ADC is configured to directly sample RF signals in the receive path in accordance with a clock signal and generate a digital signal. The synthesizer module is configured to generate the clock signal and a signal used to upconvert a transmitter signal. The clock signal and the upconversion signal are phase locked. The CNR module is configured to reduce leakage noise in the receive path.

Abstract: The present disclosure is directed to a system and method for directly sampling RF signals. In some implementations, an RF reader includes a clock generator and an Analog-to-Digital Converter (ADC). The clock generator is configured to generate a sample clock signal based, at least in part, on an input signal associated with transmitting RF signals. The ADC is configured to directly sample RF signals in a receive path of the reader using the sample clock signal to generate a digital signal. Mixing of the RF signal and the sample clock, through the sampling process in the ADC, reduces phase noise associated with the transmission signal in the receive path.

Abstract: The present disclosure is directed to a system and method for sampling intermediate radio frequencies. In some implementations, a method for RF communication includes receiving an analog Radio Frequency (RF) signal. The analog RF signal is downconverted to an analog signal centered at an Intermediate Frequency (IF). The analog IF signal is converted to a digital signal centered at an IF. The digital IF signal is downconverted to a digital baseband signal.

Abstract: The present disclosure includes a system and method for reducing leakage noise in directly sampled radio frequency signals. In some implementations, a Radio Frequency IDentification (RFID) reader includes an antenna, an Analog-to-Digital Converter (ADC), a synthesizer module, and a Carrier Noise Reduction (CNR) module. The antenna is configured to receive Radio Frequency (RF) signals and pass the RF signals to a receive path. The ADC is configured to directly sample RF signals in the receive path in accordance with a clock signal and generate a digital signal. The synthesizer module is configured to generate the clock signal and a signal used to upconvert a transmitter signal. The clock signal and the upconversion signal are phase locked. The CNR module is configured to reduce leakage noise in the receive path.

Abstract: The present disclosure is directed to a system and method for directly sampling RF signals. In some implementations, an RF reader includes a clock generator and an Analog-to-Digital Converter (ADC). The clock generator is configured to generate a sample clock signal based, at least in part, on an input signal associated with transmitting RF signals. The ADC is configured to directly sample RF signals in a receive path of the reader using the sample clock signal to generate a digital signal. Mixing of the RF signal and the sample clock, through the sampling process in the ADC, reduces phase noise associated with the transmission signal in the receive path.

Abstract: The present disclosure includes a system and method for adjusting parameters associated with leakage signals. In some implementations, an RFID reader includes an RF antenna, a transmitter section, a receiver section, a control module and a cancellation noise reduction (CNR) section. The transmitter section is coupled to the RF antenna and operable to generate a transmit signal to be transmitted by the RF antenna. The receiver section is coupled to the RF antenna and operable to receive a receive signal from the RF antenna. In addition, the receiver section further includes a de-rotation module and a control module. The de-rotation module is operable to de-rotate, by ?, an in-phase signal and quadrature signal associated with the leakage signal. The control module is operable to generate control signals used to produce a signal for reducing the leakage signal in a receive path of the reader. The CNR section is operable to subtract from the reduction signal from the leakage signal.

Abstract: The invention relates to an improved front-end circuitry for a radio transceiver for which the receiver and transmitter share a common transmission path, which is switched between the receiver and transmitter during operation. An additional switch is placed between the RF switch and the receiver circuitry, and, preferably, in close proximity to the receiver circuitry. The switch is configured to provide a low impedance electrical path to ground for the receiver circuitry input during transmission sequences and an open circuit during receiving sequences. Coupling the receiver input to ground during transmission sequences at a location proximate to the receiver input significantly reduces the amplitude of all unwanted signals appearing at the receiver's input during transmission sequences, especially attenuated and/or delayed replicas of the transmitted signal itself.