Informatie over antenne aansluitingen
Nu ik laatst wat informatie en producten wou opzoeken voor die kleine connectortjes op de ESP module, heb ik dit gevonden, uiteraard zijn er 1001 antenne aansluitingen, hier de meest voorkomende.
SMA (Subminiature A)
Komt vooral veel voor op WiFi routers en IP Camera’s.
The SMA (Subminiature A) connector was designed by Bendix Scintilla Corporation and Omni-Spectra Corporation as the OSM connector, and is one of the most commonly used RF/microwave connectors. It is intended for use on semi-rigid cables and in components which are connected infrequently. It takes the cable dielectric directly to the interface without air gaps. The threads are 0.250 x 36, and the male has a 0.312 hex body, tightened with a 5/16 inch wrench.
A few hundred interconnect cycles are possible if performed carefully. Care should be taken to join connectors straight-on. Prior to making a connection it is wise to inspect the female end to assure that the center socket is in good condition (fingers not bent or missing).
A standard SMA connector is designed for interconnects to 12.4 GHz. Fortunately, a good SMA is useable to 18 GHz in most cables, and if well constructed with greater loss and lower return loss to 24 GHz. Most SMA connectors have higher reflection coefficients than other connectors available for use to 24 GHz because of the difficulty to anchor the dielectric support. Some manufacturers rate a special high quality version of an SMA that meets SMA standards as high as 26.5 GHz (The Johnson Field Replaceable SMA goes to 26.5 GHz, and the M/A-Com OSM extended frequency series goes to 27 GHz). Because an SMA with such quality can be repeatably manufactured, you will often see test equipment and components rated to exactly 26.5 GHz with SMA connectors as the primary interconnect.
Micro RF Coax
Ook wordt het U.FL, I-PEX, IPEX, IPAX, IPX, AMC, MHF, UMCC genoemd.
Dit zijn vooral die kleine aansluitingen, o.a. te vinden op de ESP modules en IN routers
Ook daar zijn verschillende maten in te vinden:
U.FL, IPEX, IPAX, IPX, AMC, MHF and UMCC is a miniature RF connector for high-frequency signals up to 6 GHz manufactured by Hirose Electric Group and others.
U.FL connectors are commonly used in applications where space is of critical concern, most often Mini PCI cards for laptop computers. U.FL connectors are commonly used inside laptops and embedded systems to connect the Wi-Fi antenna to a Mini PCI card. Another common use is connecting GPS antennas.
Female U.FL connectors are not designed with reconnection in mind, and they are only rated for a few reconnects (approximately 30 mating cycles) before replacement is needed. The female U.FL connectors are generally not sold separately, but rather as part of a pigtail with a high-quality 1.32 mm doubly shielded cable, which allows for a low-loss connection.
The male connectors are surface-mounted and soldered directly to the printed circuit board. They are designed to have an impedance of 50 ohms. The mated connection is only 2.5 mm high and takes as little as 3 mm2 of board space.
Much like many other electronic components, Hirose U.FL connectors were protected by patents and trademarks. However, compatible connectors are on the market.
Although several companies claim to make U.FL compatibles, quality can vary. All assemblies should be tested to the original U.FL standard.
Bronnen: wa1mba.org / en.wikipedia.org