ISM antenna refers to antennas designed to operate in the Industrial, Scientific and Medical (ISM) radio bands, which covers a wide range of radio frequencies(RF) that they are now famously used for a huge range of shortrange wireless communication devices.
The key ISM Bands :
- 2.4GHz Band (2400-2500MHz) : the most common and universal all around the world. Used by WIFI (802.11b/g/n/ax), Bluetooth, Zigbee, many cordless phones and microwave ovens.
- 915MHz Band(902-928MHz): it is primarily in North & South America, used for RFID, some older cordless phones and long-range ISM devices
- 5.8GHz Band(5.725-5875GHz): operated by WIFI (802.11a/n/ax/ax) and used for some cordless phones and industrial heating
- 433MHz Band (433.05-434.79MHz): very common in Europe, Africa and Asia, key used for Keyless Entry, Tire Pressure Monitors and simple telemetry
For now, wireless devices are by far the largest usage of ISM bands, these diveces include Wi-Fi networks, cordless phones, wireless microphones, devices compatible with Bluetooth technology, garage door openers, baby monitors, wireless doorbells, keyless car entry systems, wild animal trackings and near-field communication (NFC) devices such as contactless smart cards and proximity cards.
So, when designing an IoT(Internet of Things) devices or other wireless systems, it is very important to consider the differences between the sub-GHz band versus the 2.4GHz band and how they can impact the system performance and commercial viabilities.
The sub-GHz band typically allows a longer-range wireless communication transmission than the 2.4GHz band and is more capable of penetrating objects like walls or buildings.
Sub-GHz frequency waves are less susceptible ro reflection, can bend further around obstacles, and often encounter less interference from the large amount of other wireless devices operating in license-free bands. Sub-GHz networking is the preferred wireless technology in large building environments and is more frequently used in low bandwidth or low data rate applications, while, the 2.4GHz band is used where a higher data rate is needed. Sub-GHz applications include fire alarms, hand-held payment devices, barcode scanners, smart meters, electronic point-of-sale, inventory trackings, remote process monitoring and restaurant ordering systems.
The common types of ISM antennas (especailly for 2.4Ghz / 5.8GHz)
- Dipole Antenna/Rubber Duck Antenna –common used for routers, access points and USB adapters
- Whip Antenna /Ground Plane Antenna–common used for base station and outdoor IoT
- Panel Antenna / Patch Antenna–indoor or outdoor coverage in a sector and point-to-point multipoints
- Parabolic Grid Antenna / Dish Antenna–very long-distance point-to-point links
- Sector Antenna–cellular towers, stadium and campus coverge
When choosing an ISM antenna, some important points are needed:
- Frequency
- Omni-Directional or Directional
- Polarization
- Gain
- Connector
Summary: An ISM antenna is a speciallized antenna for the license-free ISM radio bands.
MS TELECOM has a wide range of ISM antenna solutions for you and your devices, predominantly operable in the 433.92MHz, 868MHz, 915MHz,2.4GHz and 5.8GHz center frequency bands. They are including embedded antennas or internal antennas for short range communications; remote antennas, dipole antennas and terminal mount external antennas for mid-range communications; as well as outdoor external antennas for long-range communications.