A sizeable proportion of the coaxial RF connector business is for custom parts, and the strong competition in this sector means that success relies heavily on a connector vendor's responsiveness to customer requests.
One of the most successful and longest-established manufacturers in this market is San-tron. Around 70% of its business is producing custom parts, and a key element in securing these orders is the ability to produce engineering samples rapidly. San-tron will typically design a new connector within just three working days, thanks in part to an automated design process using the Concerto high-frequency electromagnetic design software, from Cobham Technical Services.
Requests for custom parts are often driven by a need for improvements in cost or performance, and often both. By using Concerto software, with its built-in automatic parameter optimisation program, San-tron is almost invariably able to find the best connector geometry in a single simulation-optimisation stage. From there, the company typically fabricates a small number of prototypes, based on the optimised design, but with minor mechanical variations. The results of electrical tests on these allow San-tron to assess the effects of tolerances in manufacture and material properties. The final design is then realised in finished samples for customer evaluation.
The complete design stage of this process is usually performed within just three working days. This includes a full three-dimensional simulation and multi-parameter optimisation exercise that takes between 30 minutes and a couple of hours, depending on the complexity of the product. Concerto's computation efficiency allows this to be performed on a standard office laptop.
Before this design process was introduced, San-tron employed analytic computer software to estimate the VSWR (voltage standing wave ratio) of a proposed connector design. Designing a new connector using this approach typically necessitated three or four physical prototyping iterations.
This approach became impractical as San-tron's business grew, and as it became involved in higher frequency applications. San-tron designs several hundred connectors every year. Many of these are mechanical variations on field-proven connectors in its standard range, and do not require electrical changes. But, in-depth design and analysis of a new concept using Concerto is typically needed for two or more products each month.
One recent Concerto-aided design project involved a panel-mounting connector for operation up to 40 GHz, following a customer request to lower the costs of an existing connector that it used. Concerto's ability to optimise a design helped San-tron's Chief Engineer Fred Hull to prototype an idea virtually that reduced the bill of materials from five component parts to four, while still matching performance.
"It would be extremely difficult and expensive to produce a high-frequency connector like this without design automation," says Fred Hull of San-tron. "I would probably need to machine and test a dozen prototypes before I could lock in a reasonable performance optimum, and that process would be far too slow and too expensive for today's marketplace. Concerto gives us the means to obtain the optimum geometry in a matter of a couple of hours."
San-tron chose Concerto as its main design tool because of its excellent price/performance ratio. The two-dimensional variant of Concerto would have been suitable for most of the company's coaxial connector design requirements, but San-tron wanted the more versatile three-dimensional package so that it could also handle customer requests for products such as coax-to-stripline and right-angled adaptors.
Full 3D software tools can be very expensive however, and after reviewing the electromagnetic EDA market, San-tron chose Cobham Technical Services' Concerto ES package - with its finite-difference time domain solver - as it offers a very low-cost entry point to full 3D electromagnetic design functionality that is suitable for smaller-scale design problems.
Having been in business for more than 50 years, San-tron is one of the longest established manufacturers of RF coaxial connectors. It makes connectors and cable assemblies in a wide variety of standard configurations from SMA through LC styles, and is renowned for its technical ability, and flexibility of manufacture and supply for application-specific components.
With its headquarters in Ipswich, Massachusetts and its own manufacturing facilities in both Ipswich and Suzhou, San-tron has the resources to meet market demands for high quality and competitive pricing, and will handle applications that require volumes from a hundred components to hundreds of thousands.