Low-Power 28GHz Selective Spectrometer

Pacific Microchip Corp. proposes to develop a 28GHz spectrometer ASIC including an 8-bit 56GS/s ADC coupled with a digital back-end for a digital poly-phase filter based parallelized Fast Fourier Transform (FFT) processing of a selected portion of the signals spectrum. To achieve the 28GHz signal bandwidth, a previously developed 8-bit 56GS/s ADC with architectural enhancements will be employed. The introduced enhancements minimize the time interleaving mismatches which results in significant reduction of unwanted artifacts in the output spectrum. Instead of overdesigning, when seeking to maximize the performance, the ADC will rely on parameter calibration using a built-in CPU. On-chip phase locked loops (PLLs) will be used for clock synthesis. For convenient interfacing with field programmable gate arrays (FPGAs), the ASIC will include a high-speed LVDS data interface for result readout and an I2C interface for the ASIC control. Phase I work provided the proof of ASIC feasibility critical blocks were implemented and verified at the targeted technology node. At Phase II, the proposed ASIC will be designed, fabricated, tested, and developed ASIC samples will be provided. NASA uses spectrometer instruments for remote exploration of various physical phenomena such as climate and environmental changes, as well as searching for planets suitable for terrestrial life forms. Features such as high-speed operation, low-power consumption, small-size and light weight are indispensable for these instruments. Conventional solutions based on an off-the-shelf ADC coupled with an FPGA will fail to achieve these features. Pacific Microchip Corp. proposes to develop a 28GHz spectrometer ASIC that includes a previously developed 8-bit 56GS/s ADC coupled with a digital signal processing (DSP) back-end which performs a poly-phase filter based parallelized Fast Fourier Transform (FFT) processing within a selected portion of the signal's spectrum. Main Objectives: 1) To design analog/mixed signal circuits, digital blocks and their layouts. 2) To integrate the circuits and layouts – to assemble the chip. 3) To complete the chip’s LVS, DRC, reliability, latch-up, and all other verifications. 4) To fabricate the die based on the 28nm HPC+ CMOS process. 5) To assemble the chips on a previously developed BGA chip carrier. 6) To design, fabricate and assemble the PCB and develop the GUI for the chip’s testing. 7) To test and characterize the ASIC, identify any problems in the ASIC’s design. 8) To prepare the specifications/description of the ASIC part. 9) To collect and organize the data, to provide the deliverables and the project report. Proposed Deliverables: Fabricated and assembled ASIC parts The ASIC testing/evaluation board Interim reports Final report
Benefits: An example is JUpiter ICy moons Explorer (JUICE) that includes a Submillimeter Wave Instrument (SWI) – spectrometer that operates in the 530–630 GHz and 1080–1275 GHz ranges. The OASIS proposed mission to MidEx is another example of instrumentation that calls for a wide-band, small-size, low-cost and low-power spectrometer solution. These and many other missions would benefit from the expanded spectral coverage and improved resolution offered by the proposed 28GHz bandwidth low-power spectrometer technology. Spectrometers are employed on satellites, aircraft and air balloons for remote sensing and surveillance. EPA and NOAA require spectrometers for spaceborne, airborne and ground based remote sensing instruments for temperature, water vapor, pollutant, ozone and other exploration. Spectrometers are also used for synthetic aperture radar, sonar or visible light, infrared or UV image processing.