A Completely Integrated Warm-IF Receiver and a 10GS/s Analog-Delay Pipeline ADC for Radio-Telescope Applications
Bibliographic record
Abstract
The Cerro Chajnantor Atacama Telescope (CCAT) Heterodyne Array Instrument (CHAI) radio-telescope is a large international effort involving University of Calgary, Kölner Observatorium für Sub-Millimeter Astronomie (KOSMA), University of Bonn, McGill University, and many others. The goal of the CHAI project is to upgrade the existing telescope capabilities to receive high-resolution images specifically in the 460 GHz and 830 GHz bands. The intended receiver system will have 128 (up to 256) antenna elements each requiring 128 independent receivers to be used. The Square Kilometer Array (SKA) is another major global effort to create the most sensitive radio telescope ever attempted. This radio telescope involves more than a hundred universities as well as industry. The SKA will potentially require millions of antenna elements, each requiring a cost-effective receiver to be implemented. This thesis presents a study of using a cost-effective CMOS technology to implement a complete receiver integrated on a single chip for CHAI and SKA telescopes. A receiver including a low-noise amplifier (LNA), a voltage-controlled oscillator (VCO), a mixer, and a variable-gain amplifier (VGA), based on CHAI design requirements, was implemented in 0.13 μm complementary metal-oxide semiconductor (CMOS) technology. An analog-to-digital converter (ADC) was implemented, based on the design requirements of the SKA, in 65 nm CMOS technology. A novel method for LNA wide-band noise optimization is developed and implemented in 0.13 μm CMOS technology. The design of the LNA is verified experimentally and meets the design requirements set by the CCAT project specifications. The LNA achieves a noise figure (NF) of <2.4 dB over the intended band of 4 GHz to 8 GHz with a gain of 18 dB. A novel method for VCO phase-noise (PN) optimization that simultaneously reduces VCO die-area and increases the available tuning range, was developed. The VCO is implemented in 0.13 μm CMOS technology and the novel optimization method is verified experimentally. The measured PN at 8 GHz is -134.3 dBc/Hz at a 1 MHz offset with a figure-of-merit (FOM) of 204 dBc/Hz. The ADC is developed using a novel topology that improves the speed performance of sub-ranging ADCs by removing the bottleneck and allowing both ADCs to run at full speed.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.006 | 0.004 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".