From Embedded Antenna Design: Four interesting antenna solutions for 868 MHz
We take a look at some interesting antenna solutions for 868 MHz that might be used for LoRA or Sigfox applications. 868 MHz in many parts of the world is a licence-free frequency band. Increasingly this frequency band is being used for IoT networks for longer range access for data applications. That being said no one antenna is suitable for every application, therefore many customers need to consider what mounting option is required and where best to position the antenna when designing an installation. Here are four suggestions:
For fixed and mobile terminals where the orientation of the device is not always certain, sometimes it helps to consider a multi-position antenna where the antenna can be moved from the horizontal to the vertical position. Terminated with a coaxial connector such as SMA, RP-SMA or TNC for example, the antenna element can be lock in three places depending on the installation.
For applications where you would need a small quarter-wave antenna, but want to discourage the removal of the antenna from the application, you could consider a captive mount model. This means that the base of the antenna is mounted through the terminal’s metal enclosure and held in place by a locking nut. A coaxial cable feeds from the bottom of the antenna through the mounting boss and can connect to the radio module.
High gain 868 MHz outdoor omni antenna
For fringe areas of signal, a 5-6 dBi outdoor omni-directional might be useful. Wall-mounted and supplied with a 5M cable to connect to the radio or device some way away, this high gain antenna can often aid reception in difficult installations. Fully weatherproof with a fibreglass tube, this antenna can be mounted outdoors permanently.
Internal 868 MHz PCB dipole antenna
A half-wave groundplane independent PCB antenna, this enables the antenna to be installed inside a non-metal terminal enclosure enabling a discreet, but functional antenna installation. Various cable and connector options are possible including U.FL, MMCX and SMA.
This list of antenna solutions for 868 MHz is not exhaustive so if you cannot what you need here, please feel free to e-mail us or use our antenna configurator.
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