Abstract: A system includes an ADC configured to generate a superposition signal by the ADC being configured to under-sample an input signal at a sampling frequency in which the input signal that is input to the analog to digital converter has a bandwidth and the sampling frequency is less than a Nyquist rate for the bandwidth of the input signal. The system includes a digital signal processor (DSP) configured to digitally process the superposition signal to separate the superposition signal into a plurality of bitstreams, where each of the plurality of bitstreams corresponds to information in a different one of a plurality of separable, distinct frequency bands within the input signal. The information in the superposition signal for at least one of the said plurality of bitstreams is present in the input signal at frequencies greater than the sampling frequency, and the DSP is configured to output said plurality of bitstreams.

Abstract: A wireless communication system include user equipment which includes a receive antenna for receiving mmWave signals from a base station transmitter. The system also includes a barrier configured to focus electromagnetic radiation carrying the mmWave signals onto the receive antenna of the user equipment.

Abstract: A mechanism is provided by which a radar image can be generated using mmWave transmissions from 5G-NR type base station antenna arrays. Base stations in 5G-NR use a beam searching sequence utilizing a defined synchronization signal burst (SSB) during their communication initialization with client devices. Embodiments utilize these SSB signals as a radar “chirp” to build a radar image of the base station surrounding in parallel with the typical 5G-NR communication initialization. Antennas on the base station can receive the reflected signals to define the radar image, in conjunction with correlation and time-management logic to properly associate received reflected signals with original transmitted signals. Such information can be processed by a synthetic aperture radar processing logic to form the radar image.

Abstract: A system includes an ADC configured to generate a superposition signal by the ADC being configured to under-sample an input signal at a sampling frequency in which the input signal that is input to the analog to digital converter has a bandwidth and the sampling frequency is less than a Nyquist rate for the bandwidth of the input signal. The system includes a digital signal processor (DSP) configured to digitally process the superposition signal to separate the superposition signal into a plurality of bitstreams, where each of the plurality of bitstreams corresponds to information in a different one of a plurality of separable, distinct frequency bands within the input signal. The information in the superposition signal for at least one of the said plurality of bitstreams is present in the input signal at frequencies greater than the sampling frequency, and the DSP is configured to output said plurality of bitstreams.

Abstract: Saturation of an A/D converter at a receiver is addressed by forcing a controlled clipping of a peak signal pulse in the analog domain and restoring the pulse using a digital algorithm within the receiver. An A/D converter saturates and clips the peak pulses in the signal. Saturated peaks are restored by an algorithm operating in a baseband digital signal processor that utilizes information related to the time intervals where clipping was applied, along with information associated with the portion of the pulse below the clipping threshold. The time interval information is available from the A/D converter or through use of a separate pulse clipping detection algorithm. Through the use of embodiments of the present invention, the effect of signal clipping on receiver performance is reduced and therefore allows for increased clipping of the received signal.

Abstract: A wireless communication system include user equipment which includes a receive antenna for receiving mmWave signals from a base station transmitter. The system also includes a barrier configured to focus electromagnetic radiation carrying the mmWave signals onto the receive antenna of the user equipment.

Abstract: A mechanism is provided by which a radar image can be generated using mmWave transmissions from 5G-NR type base station antenna arrays. Base stations in 5G-NR use a beam searching sequence utilizing a defined synchronization signal burst (SSB) during their communication initialization with client devices. Embodiments utilize these SSB signals as a radar “chirp” to build a radar image of the base station surrounding in parallel with the typical 5G-NR communication initialization. Antennas on the base station can receive the reflected signals to define the radar image, in conjunction with correlation and time-management logic to properly associate received reflected signals with original transmitted signals. Such information can be processed by a synthetic aperture radar processing logic to form the radar image.

Abstract: Saturation of an A/D converter at a receiver is addressed by forcing a controlled clipping of a peak signal pulse in the analog domain and restoring the pulse using a digital algorithm within the receiver. An A/D converter saturates and clips the peak pulses in the signal. Saturated peaks are restored by an algorithm operating in a baseband digital signal processor that utilizes information related to the time intervals where clipping was applied, along with information associated with the portion of the pulse below the clipping threshold. The time interval information is available from the A/D converter or through use of a separate pulse clipping detection algorithm. Through the use of embodiments of the present invention, the effect of signal clipping on receiver performance is reduced and therefore allows for increased clipping of the received signal.

Abstract: A receiver decodes received data streams based on a subset of candidate decoding constellation points. A first stage of a decoder of the receiver selects a subset of candidate decoding constellation points by identifying a decoded value for an initial data stream of the set of data streams. A second stage then applies MMSE error detection to each of the constellation points in the selected subset, and calculates an error metric based on the MMSE error detection results. The decoder selects the constellation points having the lowest error metrics, and uses the selected constellation points as an initial set of points for decoding the next data stream to be decoded.

Abstract: A method and apparatus for performing distributed computation of precoding estimates within a DAS. An RRH comprises a receiver component arranged to receive uplink signals from active user devices. The RRH further comprises a processing component arranged to perform channel estimation for each active user device m, based on the received uplink signals, to obtain channel estimates Hm,i between each active user device m and the RRH, compute intra-RRH interference precoding estimates Fm for each active user device m based on the channel estimates Hm,i, and solve interference-free conditions to obtain inter-RRH interference precoding estimates for each RRH j within the DAS.

Abstract: A radio frequency (RF) transceiver includes a transmitter portion configured to transmit RF signals at an output of a power amplifier (PA). A receiver portion has an input coupled to the output of the PA. The receiver portion includes a switch coupled to feedback first baseband signals to the transmitter portion during a feedback mode. The first baseband signals are based on the first RF signals received at the input of the receiver portion. A pre-distortion processing unit is coupled to receive the first baseband signals. In turn, the distortion processing unit provides pre-distortion feedback signals to the transmitter portion.

Abstract: A receiver decodes received data streams based on a subset of candidate decoding constellation points. A first stage of a decoder of the receiver selects a subset of candidate decoding constellation points by identifying a decoded value for an initial data stream of the set of data streams. A second stage then applies MMSE error detection to each of the constellation points in the selected subset, and calculates an error metric based on the MMSE error detection results. The decoder selects the constellation points having the lowest error metrics, and uses the selected constellation points as an initial set of points for decoding the next data stream to be decoded.

Abstract: A method and apparatus for performing distributed computation of precoding estimates within a DAS. An RRH comprises a receiver component arranged to receive uplink signals from active user devices. The RRH further comprises a processing component arranged to perform channel estimation for each active user device m, based on the received uplink signals, to obtain channel estimates Hm,i between each active user device m and the RRH, compute intra-RRH interference precoding estimates Fm for each active user device m based on the channel estimates Hm,i, and solve interference-free conditions to obtain inter-RRH interference precoding estimates for each RRH j within the DAS.