ROHO CONNECTOR LIMITED

    RF signal has its own characteristics, so the transmission of signal requires a special medium, the corresponding connector is also very special, here is the main description of the common rf coaxial connector, in accordance with gb11316-89, IEC169 standards, mil-c-31012 and other standards.     First. common coaxial connector and main performance table:     In addition to the above connectors, there are MINI BNC, SL16, C3, CC4 (1.0/2.3), SMZ (bt-43), MIM and other connectors, but mainly some of the company's models.     Second. Selection of common coaxial connectors     BNC is bayonet type for RF connections less than 4GHz and is widely used for instrument and computer interconnections.     TNC is thread connection, similar to BNC in size, operating frequency up to 11GHz, thread for vibration environment.     SMA is the most widely used, impedance of 50 and 75 ohms, 50 ohms, soft cable use frequency is lower than 12.4Ghz, semi-rigid cable up to 26.5 Ghz.     SMB connector is smaller than SMA in size and for fast connection inserts self-locking structure, commonly used for digital communication, is L9 replacement, 50 ohm to 4GHz, 75 ohm to 2GHz.     SMC is a threaded joint and other similar SMBS with a wider frequency range and is commonly used in military or high vibration environments.     N Type connector is screw, air insulation material, low cost, frequency up to 11GHz, often used in test equipment, there are 50 and 75 ohms two.     For dense connections, the MCX and MMCX connectors are small.     BMA for blind plug connections for low power microwave systems up to 18 GHz.     Each connector comes with military and commercial standards. The military standard is made by mil-c-39012, copper parts, PTFE insulation, inside and outside gold-plated, most reliable performance, but at a higher cost.     Commercial standard designs use inexpensive materials such as brass castings, polypropylene insulation, and silver coatings, which are less reliable.     The connector materials are brass, beryllium copper and stainless steel, and the center conductor is usually gold-plated to ensure low resistance and corrosion resistance.Military standards require gold plating on SMA and SMB, and silver plating on N, TNC and BNC, because silver is easy to oxidize and users prefer nickel.     Insulation material has polytetrafluoroethylene, polypropylene and toughened polystyrene, polytetrafluoroethylene insulation performance is the best, but the cost is higher.

    RF connectors may be small, but if you put together a sufficient number of connectors, as in a base station, you will find that these connectors and their associated cable fittings will form a network and become widely accepted.Therefore, if you can reduce the size of the connector while improving performance, simplifying installation, and reducing possible human errors, you have a good reason to replace it.These factors, as well as reduced PIM, are likely to result in familiar connector types such as N type connector and 7-16 DIN connector in microbase stations and small cells being almost or even substantially replaced by newer, smaller connectors, and the process is already under way.     Most components can be used in the back panel after the connector size is reduced, which is very important for space-limited applications.But even if these connectors may be small enough, they are not enough for wireless carriers that need more space in crowded device bunkers.In addition, applications that require high data rates, such as high-definition video, require large amounts of bandwidth, which connectors must adapt to.     Distributed antenna systems (DAS) are also hosts to a large number of digital, optical, and RF connectors that may be combined to more than 100 in a large installation.It is not feasible to replace all the connectors in existing analog DAS systems that transmit only RF signals over coaxial cables, but fortunately the field is growing fast, so a new first installation may use the latest connectors at the right price.Cable and telecoms companies have deployed hundreds of thousands of wi-fi hotspots as value-added services to customers, potentially making them a new, smaller alternative connector.Another area that could benefit from smaller connectors is the growing large market for portable RF test equipment that, in addition to its small size and high performance, requires a sturdy connector design to meet harsh field conditions.

    1. Power/level (dBm): the output capability of the amplifier, the general unit is w, mw, dBm     Note: dBm is an absolute power level expressed in decibels with 1mw as the reference value. Conversion formula:     Level (dBm)=10lgw     5W → 10lg5000=37dBm     10W → 10lg10000=40dBm     20W → 10lg20000=43dBm     It is not difficult to see from the above that every time the power is doubled, the level value increases by 3dBm     2. Gain (dB): the magnification factor, and the unit can be expressed in decibels (dB), That is: dB=10lgA (A is the power amplification multiple)     3. Insertion loss: the attenuation increased when a certain device or component is connected to the transmission circuit, and the unit is expressed in dB.     4. Selectivity: Measure the gain in the working frequency band and the suppression ability of out-of-band radiation. The -3dB bandwidth is the bandwidth when the gain is reduced by 3dB, and the same applies to -40dB and -60dB.     5. Standing wave ratio (return loss): the ratio of the antinode voltage to the node voltage (VSWR) in the traveling standing wave state     6. Third-order intermodulation: If there are two sinusoidal signals ω1 and ω2, many intermodulation components will be generated due to nonlinear effects. The two frequency components of 2ω1-ω2 and 2ω2-ω1 are called third-order intermodulation components. The ratio of the power of P3 and the signal ω1 or ω2 is called the third-order intermodulation coefficient M3, That is, M3 =10lg P3/P1 (dBc)     7. Noise figure: Generally defined as the ratio of output signal-to-noise ratio to input signal-to-noise ratio, which is calculated in decibels in actual use. The unit is dB.     8. Coupling degree: the power ratio between the coupling port and the input port, in dB.     9. Isolation: The ratio of the power of the local oscillator or signal leaking to other ports to the original power, in dB.     10. Antenna gain (dB): Refers to the ability of an antenna to concentrate its transmission power in a certain direction. Generally, the field strength E in the maximum radiation direction of the antenna is compared with the uniform radiation field strength E0 of an ideal isotropic antenna, and the multiple of the increase in power density is defined as the gain.      11. Antenna pattern: It is the range of electromagnetic waves radiated by the antenna in free space. The width of the directional pattern generally refers to the angle between the two points when the width of the main lobe drops half from the maximum value.     The E-plane pattern refers to the in-plane radiation pattern parallel to the electric field;     The H-plane pattern refers to the in-plane radiation pattern parallel to the magnetic field.  ...