IMFW 2026 Filter Tuning Competition
This competition offers participants the opportunity to showcase either the effectiveness of their Computer-Aided Tuning program or the finesse of their manual tuning skills by tuning a complex bandpass filter in the shortest possible time. Each competitor will tune a 9th‑order filter on-site using the provided tuning tools and a vector network analyzer to meet the specified requirements.
Filter Description
The 9th‑order filter is designed with 4 transmission zeros, realized through one cascade trisection and one quintet section. The coupling topology is illustrated in Fig. 1, while the synthesized coupling matrix is presented in Table I. A representative measured response of the filter is shown in Fig. 2.
Figure 1 The topology of the target filter.
Table I Synthesised coupling matrix
Figure 2 A typical measured response of the filter.
Filter Specifications
Center Frequency: 3,837 MHz | Bandwidth: 282 MHz
Reflection coefficient and rejection specifications:
Competition Procedure
- Each participant (or team) will tune the assigned filter on-site using all tools provided by the conference. A vector network analyzer (VNA) will be available; its model will be specified, and setup assistance will be provided by student helpers. The required specifications will be preloaded into the VNA.
- The initial condition of the filter is randomly set to ensure an unbiased starting point for each participant.
- Participants may choose either manual tuning or computer-aided tuning.
- For computer-aided tuning, participants must use their own laptop and proprietary software tools. The use of commercial software is not permitted.
- The total tuning time will be recorded from the initial state to the final state that meets all specifications. The maximum allowed tuning time is 30 minutes.
- The tuning setup will be available for software setup testing on February 6, and the competition will take place on February 7.
Evaluation Criteria
Total: 100 points
1. Final Filter Performance – Post-Tuning (30 points)
- Min. Insertion Loss in Passband & at Band-edges (5 pts):
Measured at both band-edge frequencies (per specification). Lower is better. - Passband Return Loss (10 pts):
S11/S22 in the passband. Higher return loss (i.e., better matching) scores higher. - Out-of-band Rejection (10 pts):
Attenuation outside passband at key frequencies. - Meets All Specs (5 pts, required):
Filter must satisfy all defined electrical specifications.
2. Tuning Efficiency (30 points)
- Total Tuning Time (20 pts):
Shorter total tuning time from start to finish scores higher. Use a formula or a tiered system (e.g., fastest = 20, next = 17, etc.). - Number of Tuning Steps (10 pts):
Fewer tuning actions/iterations to reach target; efficiency of adjustment process.
3. Tuning Process/Technique (25 points)
- Innovative Tuning Approach (20 pts):
Use of effective algorithms, rational model-based extraction, neural modeling, or creative human intuition; alignment with trends like CAT/RAT. - Instrumentation and Setup (5 pts):
Efficient choice and use of tuning tools/automation and measurement system.
4. Presentation and CAT Tool (15 points)
- User Friendliness of CAT Software (10 pts):
Quality of CAT software and industrial features. - Oral Explanation (5 pts):
Ability to explain tuning methods, difficulties, and challenges in front of judges.
Additional Rules/Details
- Disqualification criteria:
Filter does not meet any defining specifications, or tuning time exceeds 30 min. - Bonus (+5):
Exceptional demonstration of future-ready CAT/RAT approaches, or breakthrough reduction in required tuning steps.
Data for Testing
To help participants to prepare computer-aided tuning tools, a set of measured S‑parameter (.s2p) data is provided.
Download Test Data: Access S-parameter Test Data
Data Acquisition Guide
Learn about the VNA equipment and Python scripting for S-parameter measurements. Essential reference for developing your own computer-aided tuning tools.