An Ultraminiaturized Self-Quadruplexing Antenna for Next-Generation Wireless Implantable Devices
Bibliographic record
Abstract
This work introduces a small self-quadruplexing antenna created for use in implantable medical devices (IMDs), capable of simultaneously and independently supporting transmission and reception across four different frequency bands without the need for any external multiplexer or switching circuitry. The proposed antenna operates at 868 MHz, 915 MHz [industrial, scientific and medical (ISM)], 1400 MHz [wireless medical telemetry service (WMTS) band] and 2450 MHz (ISM band) when Ports 1, 2, 3, and 4 are excited, respectively. The antenna is replicated inside a rectangular gadget that is situated inside a human phantom head model. It consists of four independently excited circular quadrants sharing a common ground plane, with compactness achieved through the use of shorting pins, strategically shaped slots and high dielectric substrate to reduce structure size. The total antenna volume is only 24.69 mm3. Mutual coupling between any two ports is maintained below -23 dB. The antenna provides peak gains of -22.8, -25.3, 25.4, and -20.2 dBi at 868, 915, 1400, and 2450 MHz, respectively. To comprehend the antenna’s electromagnetic activity, Characteristic Mode Analysis (CMA) is used. To confirm that the antenna is suitable for implantation in the body, a specific absorption rate (SAR) analysis and a link budget analysis are carried out. The maximum 1 g SAR values are found to be within safe limits, while link margin analysis confirms the potential for reliable wireless communication in biomedical telemetry applications. By integrating multiple functions into a single structure, this self-quadruplexing design offers a novel and efficient alternative to conventional multiplexed systems in IMDs.
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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 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".