A GNSS receiver comprises a memory interface and a vector processor. The vector processor is configured to: receive, via the memory interface, an array comprising a plurality of correlation results stored in a memory, each correlation result associated with a respective combination of possible receiver parameters for the GNSS receiver; process the array to identify a subset of the correlation results in the array; and retain, in the memory, the identified subset and discard, from the memory, those correlation results of the plurality of correlation results not in the identified subset.

Sets of digital samples associated with received wireless signals are received, each of the sets of digital samples corresponding to a particular RF path. The sets of digital samples are provided to a plurality of pipelines, each of the plurality of pipelines including a plurality of stages, each of the plurality of stages including one or more digital logic circuits. Sets of interconnect data are generated by the plurality of pipelines based on the sets of digital samples, the sets of interconnect data including at least one accumulating value. The sets of interconnect data are passed between adjacent pipelines of the plurality of pipelines along a direction. A result is generated by a last pipeline of the plurality of pipelines based on the at least one accumulating value.

We have demonstrated that the bandwidth millimeter wavelengths offer can be leveraged to deeply spread a low-data rate signal below the thermal floor of the environment (sub-thermal) by lowered transmit power combined with free space losses, while still being successfully received through a novel dispreading structure which does not rely on pre-detection to extract timing information. The demonstrated data link ensures that it cannot be detected beyond a designed range from the transmitter, while still providing reliable communication. A demonstration chipset of this sub-thermal concept was implemented in a 28 nm CMOS technology and when combined with an InP receiver was shown to decode signals up to 30 dB below the thermal noise floor by spreading a 9600 bps signal over 1 GHz of RF bandwidth from 93 to 94 GHz using a 64 bit spreading code. The transmitter for this chipset consumed 62 mW while the receiver consumed 281 mw.

Sets of digital samples associated with received wireless signals are received, each of the sets of digital samples corresponding to a particular RF path. The sets of digital samples are provided to a plurality of pipelines, each of the plurality of pipelines including a plurality of stages, each of the plurality of stages including one or more digital logic circuits. Sets of interconnect data are generated by the plurality of pipelines based on the sets of digital samples, the sets of interconnect data including at least one accumulating value. The sets of interconnect data are passed between adjacent pipelines of the plurality of pipelines along a direction. A result is generated by a last pipeline of the plurality of pipelines based on the at least one accumulating value.

Sets of digital samples associated with received wireless signals are received, each of the sets of digital samples corresponding to a particular RF path. The sets of digital samples are provided to a plurality of pipelines, each of the plurality of pipelines including a plurality of stages, each of the plurality of stages including one or more digital logic circuits. Sets of interconnect data are generated by the plurality of pipelines based on the sets of digital samples, the sets of interconnect data including at least one accumulating value. The sets of interconnect data are passed between adjacent pipelines of the plurality of pipelines along a direction. A result is generated by a last pipeline of the plurality of pipelines based on the at least one accumulating value.

We have demonstrated that the bandwidth millimeter wavelengths offer can be leveraged to deeply spread a low-data rate signal below the thermal floor of the environment (sub-thermal) by lowered transmit power combined with free space losses, while still being successfully received through a novel dispreading structure which does not rely on pre-detection to extract timing information. The demonstrated data link ensures that it cannot be detected beyond a designed range from the transmitter, while still providing reliable communication. A demonstration chipset of this sub-thermal concept was implemented in a 28 nm CMOS technology and when combined with an InP receiver was shown to decode signals up to 30 dB below the thermal noise floor by spreading a 9600 bps signal over 1 GHz of RF bandwidth from 93 to 94 GHz using a 64 bit spreading code. The transmitter for this chipset consumed 62 mW while the receiver consumed 281 mw.

A GNSS receiver comprises a memory interface and a vector processor. The vector processor is configured to: receive, via the memory interface, an array comprising a plurality of correlation results stored in a memory, each correlation result associated with a respective combination of possible receiver parameters for the GNSS receiver; process the array to identify a subset of the correlation results in the array; and retain, in the memory, the identified subset and discard, from the memory, those correlation results of the plurality of correlation results not in the identified subset.

Doppler correlators are configured to receive samples of a signal sampled based on a frequency. Each Doppler correlator includes successive butterfly elements. Each butterfly element includes cross-coupled first and second branches that include a sample delay that doubles for each successive butterfly element, and a sample inversion selectively placed in one of the first and second branches to encode into the successive butterfly elements of each Doppler correlator the same code sequence. Each Doppler correlator is configured with a respective phase rotation that varies across the Doppler correlators. Each Doppler correlator is configured to correlate the samples against the code sequence and apply the respective phase rotation to the samples as the samples are shifted through the successive butterfly elements, to produce respective correlation results from each Doppler correlator centered on a respective frequency offset from the frequency that varies across the Doppler correlators based on the phase rotations.

Doppler correlators are configured to receive samples of a signal sampled based on a frequency. Each Doppler correlator includes successive butterfly elements. Each butterfly element includes cross-coupled first and second branches that include a sample delay that doubles for each successive butterfly element, and a sample inversion selectively placed in one of the first and second branches to encode into the successive butterfly elements of each Doppler correlator the same code sequence. Each Doppler correlator is configured with a respective phase rotation that varies across the Doppler correlators. Each Doppler correlator is configured to correlate the samples against the code sequence and apply the respective phase rotation to the samples as the samples are shifted through the successive butterfly elements, to produce respective correlation results from each Doppler correlator centered on a respective frequency offset from the frequency that varies across the Doppler correlators based on the phase rotations.

Space-time-frequency multiplexing (STFM) schemes for radio frequency (RF) scanning are disclosed in which complementary pairs of sequences (or Golay pairs) are transmitted at different times using multiple frequencies. The transmission and reception of the sequences can occur over multiple transmit (Tx) and/or receive (Rx) radio sectors to scan an entire area for range, azimuth, elevation, and (optionally) velocity of objects therein.