PAGE CONTENTS
Objectives
DIATOOL will be a stand-alone commercial program performing advanced electromagnetic processing of measured antenna data.
DIATOOL will read the measured field and compute the extreme near-field or the currents on the antenna surface, without the fundamental constraints of the traditional measurement systems. From the inspection of the extreme near-field and currents, DIATOOL will solve typical antenna diagnostics problems, such as identification of array element failure and antenna surface errors, but also allow to artificially remove undesired contributions, such as currents on cable and fixture, saving valuable time and resources in the antenna design and validation process.
The objective of this project is to provide a powerful data processing tool for the advanced antenna engineer. DIATOOL will allow post-processing of the measured field and reconstruct ion of the extreme near-field or the currents on the antenna surface, without the fundamental constraints of the traditional measurement systems.
The inspection of the extreme near-field and currents will identify the electrical or mechanical errors in the antenna which cause undesired anomalies in the far-field, saving valuable time and resources in the antenna design and validation process. The comparison between expected surface currents and surface currents reconstructed from measurements is not possible today. Therefore, DIATOOL will be the missing link in the antenna design loop:
DIATOOL will be based on two field reconstruction techniques, i.e. the SWE-PWE, and a new and accurate source reconstruction technique based on an inverse Method of Moments algorithm. A high-quality GUI will guide the user through all the steps, i.e. from defining the Antenna Under Test to plotting the reconstructed fields and currents.
Challenges
DIATOOL will include two different electromagnetic models for antenna diagnostics:
- A SWE-PWE method, which computes a plane wave expansion of the measured field data based on full-sphere measurements. The near field can be reconstructed on a plane in the immediate vicinity of the antenna under test. The method is fast and efficient.
- An inverse Method of Moments (INV-MOM) which takes full-sphere or truncated measurement data as input and transforms the data by means of an integral equation back to an arbitrary three-dimensional closed surface containing the AUT. The method is very accurate but the memory requirement grows with the electrical size of the antenna.
Plan
TICRA will adopt a customer-oriented development approach. We intend to identify and interview potential customers and providers of measurement ranges to ensure that DIATOOL will fit into the end-user’s operating environment and solve the typical customer problems. When the user requirements are established, the software will be designed in multiple stages: The first design phase is aimed at arriving at a high-level design and a very minimal prototype of the software will be programmed. The second design phase will lead to the detailed software design which will finally be implemented in the final phase of the project.
Current Status
The contractor has just completed the first two phases of the project, i.e. Phase 1 “User requirements” and Phase 2 “Modelling”.
In Phase 1, three potential customers and one provider of measurement ranges have been identified and interviewed, in order to obtain concise view of the requirements for the DIATOOL software.
Phase 2 has been focused on the models requirements, development and validation. First, a complete set of requirements has been established, for the INV-MOM and SWE-PWE algorithms, separately. Canonical test cases have been analyzed by both models, including cases involving synthetic data and noise. The modelling and the validation have been successful for both algorithms.
The next phase is Phase 3 “Software requirements and design”, where the high level design of the DIATOOL analysis engine and DIATOOL GUI will be established.