New RF Coaxial Connectors Evolve as Emerging Technologies Demand Greater Performance
The IoT, 5G, and advancing technologies across markets have led to smaller, higher performance RF coaxial connectors.
There are times when economics and technical advances join to produce major changes in new applications, prompting the next generation of components to provide needed results. Even with the uncertainties caused by the COVID-19 pandemic, the advances prompted by 5G, the Internet of Things (IoT), new threat scenarios in military and space involving signal intelligence and electronic warfare capabilities, plus continued trends for miniaturization, commercial-off-the-shelf (COTS) connectors, and faster and better performance, including testing, interactive machine-to-machine (M2M) production, and connected cars, make this a challenging time for the RF coaxial connector industry. Supply chain sourcing problems have been exacerbated by the pandemic. Material and process challenges are an ongoing issue, from important subtleties such as the use of arsenic-gold hardening agents when the EU says “no,” adding electro-polishing to achieve low passive intermodulation (PIM), or just providing higher temperature capability for lead-free solder processing for already-installed field-replaceable and compression-mount coax connectors. Today’s advanced requirements can push the limits of design and production. For microwave and higher frequency applications, buyers should obtain test reports to confirm performance.
Suppliers of electrical connectors, and especially RF coaxial types, continue to produce new variations to meet industry needs and keep pace with application advances. Most RF coaxial connectors can be used in many different end-use applications and markets. This makes attempts at defining end-use applications and markets difficult. For example, the same 2.92mm connector could be used in medical imaging equipment and satellites plus radios and test equipment, while the new E-band 1.35mm connectors are suitable for 5G backhaul systems, connectorized microwave components, test systems including vector network analyzers (VNAs), and self-driving vehicles. RF connectors are also being designed to replace waveguides and support frequencies above the 145GHz provided by Anritsu’s 0.8mm connectors.
New Connector Developments Inspired by 5G and IoT
RF coax connectors are increasingly important as the number of fixed communications and wireless enabled devices and the amount of data consumed grows at an almost unfathomable rate. The global forecast is for over 2.7 billion 5G connections by 2025 (per CCS Insights). The COVID-19 pandemic has slowed the standardization work needed to enable availability of 5G for enterprise implementations. Limitations occurring during today’s different work scenarios will add Io pent-up demand to assure fast growth.
Bishop & Associates forecasts that by 2025, 21% of all worldwide cellular connections will be 5G, which offers great potential for RF coax connectors, ranging from ultra-miniature board-to-board (B2B) for handheld and mobile devices to higher power and lower PIM connectors for base stations, and V- and E-band interconnects for greater bandwidth backhaul sites, plus all the associated infrastructure equipment, cables, and adapters.
The market for 5G small cells will be one of the fastest growing 5G segments, as installations in population-dense areas may be as close as 100 yards apart as well as layered within larger buildings. This will involve families of new coax connectors such as NEX10, 2.2/5, and 1.5/3.5 DIN, together with myriads of multi-port assemblies for antenna housings that can have upwards of 30 cable entries.
COVID-19 is expected to result in a paradigm shift in the way that business, education, and commerce will be conducted. Expansions in internet, telecommunications, cyber-security (commercial and military), unmanned aerial vehicles (UAVs), and other implementations will increase both the need and the rate of change for new application solutions involving RF devices. Whether it’s the ability to reuse frequencies, have more functions in smaller devices, or operate tomorrow’s vehicles, the future for RF coaxial connectors looks excellent. But which connectors will have greatest demand and offer best investment returns?
Design, production tolerances, test equipment, and methods all become more complex as frequency increases. Usually, specific-product (financial) margins follow frequency; for example, a 40GHz 2.92mm should be more profitable (and costly) than a 20GHz SMA. Higher production quantities favor lower frequency connectors having simpler technology and lower cost. As a result, most higher performance microwave and millimeter wave products are manufactured in the U.S. or Europe, while the majority of lower frequency RF interconnect currently are produced in Asia.
Key suppliers of microminiature board-to-board and cable-to-board RF coax connectors include Hirose Electric, I-PEX Connectors, and JAE (an NEC Company), based in Japan, plus Amphenol SV Microwave, Molex, and Samtec in the U.S., along with European suppliers such as Radiall and Rosenberger. China is able to offer higher frequency connectors, but its stainless steel can have residual magnetic properties and surface corrosion, indicating alloy impurities.
RF Technologies Drive Growth in Many Markets
Several market areas have unique growth potentials. 5G communications will use the redefined E band for backhaul transmission, prompting the development of microwave connectors performing to 92GHz, while expanding sales for lower frequency standard and low-PIM connectors such as 4.1/9.5 “mini-DIN”, N, 7/16, and 4.3/10. Mobile 5G and IoT devices will also expand demand for the automated production and installation of microminiature RF coaxial connectors such as U.FL, X.FL, MHF/PCIe, and miniatures such as MMCX and HD-BNC, primarily for operation to 6GHz. High-speed video for the 2021 Olympics (postponed from 2020) and surveillance UAVs will require new 18GHz, 75Ω coax connectors and cables.
Coax connectors continue to keep pace with application advances. Vehicles will be served by new FAKRA-mini versions operating to 17GHz. Phase-steered antennas, progressively smaller instrumentation, and 5G New Radio (NR) will increase the use of miniature blind-mates such as SMP3. Larger commercial assemblies may incorporate new connectors per VITA 67.3, while the recently established SOSA Consortium is specifying other VITA Open-VPX connectors for military programs. Leading-edge test equipment will expand use of compression-mounted coax jacks and fly-over assemblies. RF connectors are also being designed to replace waveguides to support frequencies above the 145GHz provided by Anritsu’s 0.8 mm connectors.
As the use of RF coaxial connectors expands, concerns exist, including:
- Delivery slowdown due to supply chain restarts from effects of COVID-19 and resultant relocation of suppliers away from Asian sources
- Extended timeline for finalization of specifications for 5G and IoT
- Military and government budget uncertainties
- U.S. vs. China policies for export and import and potential tariffs
- Competitive negotiations for new international connector standards (especially IEC) and auctions for use of additional frequency bands
- Costs and lead-times for new test equipment
- Availability of quality cables and cable assemblies for higher frequency applications
- Impact of counterfeit connectors and cables involving fraudulent copies, uncertified materials, bypassed testing, and unapproved sourcing. (Estimates of counterfeit content in US interconnect supply chain range from 15% to 65% per GAO and DLA/S-DSCC inputs.)
- Supplier outlays to control and document increased restrictions, from expanded EU REACH and SEC Conflict Materials, to California Prop. 65.
Bishop & Associates’ “World RF Coax Connector Market 2020” new information-intensive, 12-chapter, 380‐page research report presents worldwide and regional sales forecasts for RF coaxial connectors by connector types and related RF cable assemblies, plus technical details and application information on RF coax connectors, accessories, adapters, and industry standards, and identifies key suppliers for each series. Click here for a detailed table of contents and ordering information for World RF Coax Connector Market 2020.