A wireless communication device converts a signal component, which has one of distributed frequency bands in an analog RF signal and passes through one of a plurality of bandpass filters, into digital data with an AD converter that carries out undersampling. A sampling frequency of the AD converter is set so that frequencies which are integral multiples of a Nyquist frequency based on the sampling frequency do not fall within frequency bands of signal components which are of the RF signal and are to pass through the respective plurality of bandpass filters.

A signal receiver includes a multiplexer, a sub-sample analog-to-digital converter (ADC) and a received signal strength indicator (RSSI) estimator for a signal receiver with multiple stage cascade amplifiers architecture. The multiplexer may select one of the input signal of each stage of cascade amplifiers or the last stage output signal of cascade amplifiers as a selected signal according to a selection signal. The sub-sample ADC may perform a sub-sampling operation using the selected signal to generate sampled data. The RSSI estimator may calculate a RSSI value corresponding to the selected signal according to the sampled data.

An array-based Compressed sensing Receiver Architecture (ACRA) includes an antenna array with two or more antennas connected to two or more ADCs that are clocked at two or more different sampling rates below the Nyquist rate of the incident signals. Comparison of the individual aliased outputs of the ADCs allows for estimation of signal component characteristics, including signal bandwidth, center frequency, and direction-of-arrival (DoA). Multiple digital signal processing (DSP) techniques, such as sparse fast Fourier transform (sFFT), can be employed depending on the type of detection or estimation.

A transmitter of an RFID communication system to transmit an amplitude modulated transmitter data signal in resonance in an RF-Field over the air and to receive a modulated receiver data signal, which transmitter comprises: a transmitter stage to generate the amplitude modulated transmitter data signal with a particular frequency and waveform based on a carrier signal generated by a carrier signal stage; an antenna connected to the transmitter stage via a matching circuit to transmit the amplitude modulated transmitter data signal in resonance in the RF-Field over the air; a receiver stage connected via the matching circuit to the antenna to receive the modulated receiver data signal; wherein the transmitter furthermore comprises a wave shape measurement stage to measure the shape of the received modulated receiver data signal with equivalent time sampling.

A transmitter of an RFID communication system to transmit an amplitude modulated transmitter data signal in resonance in an RF-Field over the air and to receive a modulated receiver data signal, which transmitter comprises: a transmitter stage to generate the amplitude modulated transmitter data signal with a particular frequency and waveform based on a carrier signal generated by a carrier signal stage; an antenna connected to the transmitter stage via a matching circuit to transmit the amplitude modulated transmitter data signal in resonance in the RF-Field over the air; a receiver stage connected via the matching circuit to the antenna to receive the modulated receiver data signal; wherein the transmitter furthermore comprises a wave shape measurement stage to measure the shape of the received modulated receiver data signal with equivalent time sampling.

A timing signal diagnostic system includes a chassis housing an input system that receives a timing signal, a timing system that receives the timing signal from the input system, an analog-to-digital converter system that receives the timing signal from the input system, and a processing system that is coupled to the timing system and the analog-to-digital converter system. The processing system uses the timing system to output reference time signals to the analog-to-digital converter system that are based on the timing signal, and uses the analog-to-digital converter system to sample the timing signal based on the reference time signals over a plurality of different timing signal cycles. Based on the sampling of the timing signal, the processing system generates a waveform for the timing signal, and provides a timing signal diagnostic result based on the waveform for the timing signal.

An array-based Compressed sensing Receiver Architecture (ACRA) includes an antenna array with two or more antennas connected to two or more ADCs that are clocked at two or more different sampling rates below the Nyquist rate of the incident signals. Comparison of the individual aliased outputs of the ADCs allows for estimation of signal component characteristics, including signal bandwidth, center frequency, and direction-of-arrival (DoA). Multiple digital signal processing (DSP) techniques, such as sparse fast Fourier transform (sFFT), can be employed depending on the type of detection or estimation.

A transmitter of an RFID communication system to transmit an amplitude modulated transmitter data signal in resonance in an RF-Field over the air and to receive a modulated receiver data signal, which transmitter comprises: a transmitter stage to generate the amplitude modulated transmitter data signal with a particular frequency and waveform based on a carrier signal generated by a carrier signal stage; an antenna connected to the transmitter stage via a matching circuit to transmit the amplitude modulated transmitter data signal in resonance in the RF-Field over the air; a receiver stage connected via the matching circuit to the antenna to receive the modulated receiver data signal; wherein the transmitter furthermore comprises a wave shape measurement stage to measure the shape of the received modulated receiver data signal with equivalent time sampling.

One or more first signals and one or more second signals, wherein the second signal(s) are slowly varying or low frequency signals in comparison with the first signals and are converted from analog to digital by sampling the first signals and the second signals to produce samples thereof for analog-to-digital conversion, subjecting the samples of the first signals to conversion to digital at a certain conversion rate, subjecting the samples of the second signal to conversion to digital by segments so that these segments are subjected to conversion to digital along with the samples of the first signals at the respective conversion rate, and reconstructing digital converted samples of the second signal from the segments subjected to conversion to digital.

A timing signal diagnostic system includes a chassis housing an input system that receives a timing signal, a timing system that receives the timing signal from the input system, an analog-to-digital converter system that receives the timing signal from the input system, and a processing system that is coupled to the timing system and the analog-to-digital converter system. The processing system uses the timing system to output reference time signals to the analog-to-digital converter system that are based on the timing signal, and uses the analog-to-digital converter system to sample the timing signal based on the reference time signals over a plurality of different timing signal cycles. Based on the sampling of the timing signal, the processing system generates a waveform for the timing signal, and provides a timing signal diagnostic result based on the waveform for the timing signal.