Synthesis of microwave bandpass filters based on planar quarter-wavelength resonators
Bibliographic record
Abstract
This Ph.D thesis is dedicated to explicitly synthesize the size-miniaturized and robustly-performed microwave bandpass filters based on planar quarter-wavelength (λ/4) resonators. Unlike the conventional bandpass filters (BPFs) based on J coupling only or K coupling only, λ/4 resonators are necessarily coupled by alternative J and K inverters to realize BPFs. The exemplified filters in this thesis not only include single-band bandpass filters (SB-BPFs) with all-pole Chebyshev and quadruplet frequency responses, but also the dual-band bandpass filters (DB-BPFs) and a tri-band bandpass filter (TB-BPF) based on the λ/4 stepped impedance resonators (SIRs). \n \nAccording to the literature survey on the classical filter synthesis, the conventional even-order lowpass Chebyshev ladder network features the unequal input/output (I/O) impedances. Hence, a novel even-order Chebyshev lowpass prototype is presented here to achieve the equal I/O terminations. This proposed Chebyshev prototype is then deployed to synthesize BPFs based on λ/4 resonators. The equivalent network transformation from the conventional J or K immittance bandpass prototypes to the ones based on λ/4 resonators coupled by alternative J and K inverters is performed and discussed in details. Following that, an explicit full-wave dimension extraction method is then proposed to rigorously extract the filter’s physical dimensions, whose robustness is demonstrated by synthesizing series of SB-BPFs with either all-pole Chebyshev frequency responses or the quadruplet frequency responses with analytical finite transmission zeros. \n \nFurthermore, the bandpass filter prototype with planar λ/4 resonators and alternative J and K inverters is extended for the DB-BPF application. Since the K inverter’s value of quasi-lumped metallic through via increases monotonically with frequency, the dimensions of concerned λ/4 SIRs are analytically determined to compensate for the dual-band values of K inverters. With the dual-band J couplings and the newly-proposed dual-band external couplings structures, a class of compact and robustly-performed DB-BPFs are proposed and designed. Besides the DB-BPFs based on dual-band λ/4 SIRs, the novel split-type DB-BPF based on the uniform λ/4 resonators is also presented, which is more suitable for the DB-BPF application with closely proximate dual passbands. Lastly, we also exemplify a TB-BPF design. Experimental results successfully justify our filter synthesis methodology in this thesis.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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 teacher head, 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".