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SLK Types of RF coaxial connectors

2023-04-27

Today, RF coaxial connectors have appeared in all fields, so practitioners in the connector industry should know about certain types of RF coaxial connectors. Below, engineers will pick out complete RF coaxial connector types for you.


Coaxial connectors are used to transmit RF signals in the frequency range up to 18 GHz or higher. The basic structure of coaxial connectors used in radar, communication, data transmission and aerospace equipment includes: a center conductor (positive) or negative center contact); a dielectric material outside the inner conductor or insulator; the outermost layer is the outer contact A point that acts like a shield on the outside of a coaxial cable, i.e., transmits the signal as a shield or ground element of the circuit. RF coaxial connectors can be divided into various types. Below are some of the more common types.



SMA connector


SMA connector is a widely used small thread coaxial connector with frequency bandwidth, excellent performance, high reliability and long life. Suitable for connections in RF loops of microwave equipment and digital communication systems. In wireless devices, RF cables or microstrip lines are usually used as the GPS clock interface on the board and the test port of the base station RF module. Originated in the 1960s, it is the most widely used connector in the microwave and radio frequency industries. The outer conductor has an inner diameter of 4.2mm and is filled with PTFE. Standard SMA connectors operate at 18GHz, while precision SMA connectors can operate at frequencies up to 27GHz.



BNC connector


The BNC connector is also one of the common RF connectors, which can be connected quickly. Originated in the 1950s, it is a bayonet type connector, which is convenient and quick to plug and unplug. The operating frequency of the current standard BNC connector is 4GHz. It is generally believed that after exceeding 4GHz, electromagnetic waves will leak out of its slot. BNC connectors are widely used in wireless communication systems, televisions, test equipment, and other radio frequency electronic equipment. Early computer networks also used BNC connectors. The BNC connector supports a range of characteristic frequencies from 0 to 4 GHz. There are two types of impedance: 50 ohms and 75 ohms.


N type connector


N-type connector (type N connector), threaded, rotatably locked. It is one of the earliest connectors used to transmit microwave frequency signals, invented by Paul Neill of Bell Labs in the 1940s and named after Neill's initials. The signal frequency range supported by the N-type connector is 0 to 11 GHz, and the enhanced type can reach 18 GHz. There are two types of characteristic impedance: 50 ohms (widely used in mobile communications, wireless data, paging systems, etc.) and 75 ohms (mainly used in cable TV systems).


SMB connector


The full name of SMB is SubMiniature Version B. It is a small push-in locking RF coaxial connector with small size, light weight, easy to use and excellent electrical performance. Suitable for high frequencies in radio equipment and electronic instruments. Connect the coaxial cable into the loop. It is often used for the connection of E1 transmission cables on the base station side on wireless devices, and the DDF small transmission box of the base station is used. Originated in the 1960s, the size is smaller than the SMA connector. There are two types of characteristic impedance: 50 ohms and 75 ohms have excellent electrical characteristics in the frequency range from DC to 4 GHz. SSMB is a miniature version of the SMB connector that supports up to 12.4 GHz.


SMC connector


The full name of SMC is SubMiniature C version, which is also an RF coaxial connector invented in the 1960s. It uses a #10-32 UNF threaded interface to provide excellent electrical performance from DC to 10 GHz. SMC males have external threads and SMC males have matching nuts. There are two types of impedance: 50 ohms and 75 ohms. Interconnects are used in small coaxial cables and very large size printed circuit boards.


F connector


The F-type connector is a radio frequency connector that everyone can see in daily life. It is widely used in cable TV, satellite TV, cable modem and TV fields. It can be used in applications with impedance matching requirements or areas of mismatch. It features a threaded connection and easy insertion. Stable performance. The F-type connector was invented by Eric Winston in the early 1950s and later became the connector for VHF television antennas, which became common in the United States in the 1970s. The price of the connector is very low, the characteristic impedance is 75 ohms, and the highest frequency can usually support up to 1 GHz or 2.4 GHz.


RCA connector


RCA is short for American because the RCA connector was invented by this company in the 1940s. RCA is usually called Lotus socket, also known as AV terminal, AV interface, almost all TV sets and DVD players have this interface. It is not designed for which interface, it can be used for audio and common video signals. Typical bearer signal range is 0-100 MHz.


7/16 DIN connector


DIN (also known as 7/16 or L29) series coaxial connector is a large threaded connector with 50 ohm impedance, which has strong stability, low loss, high working voltage, and most of them are waterproof, available in It is used outdoors as a medium-strength and high-energy transmission connector, widely used in microwave transmission and mobile communication systems, usually used in base station antenna feeder connectors, antenna connectors, etc. DIN is an abbreviation for the German Institute for Standardization and is a series of connectors. N-joints are very similar. The diameter of the DIN head is larger, about twice the diameter.


TNC connector


The TNC connector is close to the BNC, and the biggest advantage of the TNC connector is that it has good shock resistance. The standard operating frequency of the TNC connector is 11GHz, and the precision TNC connector is also called the TNCA connector, and the operating frequency can reach 18GHz. Widely used in radio equipment and electronic instruments to connect RF coaxial cables.


UHF connector


This has a long history and has been used since World War II. Its other name "UHF connector" comes from the definition of UHF at that time (the frequency above 30MHz is the UHF frequency range). Now, tests of this type of connector show that its characteristics are mainly suitable for frequencies around 100 MHz. This is what is now commonly referred to as the VHF band.


MCX connector


The MCX connector originated in the 80s and has the same internal contact and insulator dimensions as the SMB connector, but is 30% smaller than the SMB. Since MCX connectors adopt a push-in connection method, the connection and separation of the connectors is very fast, and the installation time of the connectors is shortened. MCX connectors have good electrical performance at frequencies up to 6 GHz and can also be used. The adapter includes a variety of cables, such as semi-rigid and flexible, for reliable connections and long life.


4.3-10 connector


The 4.3-10 connector is a reduced version of the DIN 7/16 connector, and its internal structure and engagement method are similar to DIN 7/16. The standard operating frequency of the 4.3-10 connector is 6GHz, and the precision 4.3-10 connector can work up to 8GHz. 4.3-10 connectors also have good passive intermodulation performance.


SMP and SSMP type connectors


Both SMP and SSMP connectors are polarized connectors with a plug-in structure, and are often used in circuit boards for miniaturized equipment. The standard operating frequency of SMP connectors is 40GHz. SSMP connector is also called Mini SMP connector, its size is smaller than SMP connector, and its working frequency can reach 67GHz.


SMP male connectors include three types: light hole, half escapement, and full escapement. SSMP male connectors include light hole and full escapement types.


The inner diameter of the outer conductor of the 3.5mm connector is 3.5mm, the standard operating frequency is 26.5GHz, and the maximum operating frequency can reach 34GHz.



The inner diameter of the outer conductor of the 2.92mm connector is 2.92mm, and the standard operating frequency is 40GHz.



The inner diameter of the outer conductor of the 2.4mm connector is 2.4mm, and the standard operating frequency is 50GHz.



The inner diameter of the outer conductor of the 1.85mm connector is 1.85mm, the standard operating frequency is 67GHz, and the maximum operating frequency can reach 70GHz.



The inner diameter of the outer conductor of the 1.0mm connector is 1.0mm, and the standard operating frequency is 110GHz. The 1.0mm connector is currently the coaxial connector with the highest operating frequency.