What is Radio Frequency (RF)?
Radio frequency is typically a frequency from 20 kHz to 100 GHZ. RF is usually referred to whenever a signal is radiated through an enclosed medium like a transmission cable or air.
What is antenna gain, and how is it measured?
Gain is an increase in effective radiated power (ERP) from an antenna, usually stated in dB (deciBels).
As a rule of thumb, you can multiply the radio’s output power by 4 for 6dB antennas and by 8 for 9dB antennas. A 3dB antenna gain gives an ERP of 2 times the radio’s output power. A Unity Gain antenna provides no increase in ERP.
What does passive and active mean?
A passive antenna has no active amplifier parts, it is just an antenna. An active antenna includes a preamplifier or amplifier to increase the gain of the antenna, but it can also refer to an electronic means to tune or match the antenna.
What is antenna polarity?
The polarity of an antenna is the orientation of the electric field of the radio wave with respect to the Earth's surface. Antennas can have vertical polarization, horizontal polarization or both.
What is patch antenna?
Patch antennas are also known as panel, flat panel or microstrip antennas. They are formed by overlaying two metallic plates, one larger than the other, with a dielectric sheet in the middle. This type of antenna is usually encased in white or black plastic, not only to protect the antenna, but also to make it easy to mount. Because they are flat, thin and lightweight, patch antennas are often hung on walls or ceilings where they remain visually unobtrusive and blend easily into the background.
Do I need an amplifier for my antenna?
Through use of an amplifier, it is to enhance signal gain, and help antennas overcome size or height disadvantages.
How do I choose the correct WiFi antenna?
The two main types of antennas are Omni-directional and directional. Omni-directional antennas radiate RF signal in a 360 degree pattern and directional antennas emit the RF signal in a focused beam similar to the headlight of a car. If your application is a point to point WiFi link like from one building to another you would use a Directional antenna. If you need to send the WiFi signal 360 degrees then you would use and Omni directional antenna. If you have a point to multi point application, such as a campus environment then you would use a combination of Omni directional and Directional antennas.
What is 802.11?
802.11 is an IEEE standard for implementing wireless local area network (WLAN) communications in the 2.4, 3.6 and 5 GHz frequency bands. Previously released 802.11 standards include 802.11a, 802.11b, 802.11g, and 802.11n. The latest pre-release standard is 802.11ac which promises wireless speeds over 1 Gbps.
What is GNSS?
Global Navigation Satellite System (GNSS) refers to a constellation of satellites providing signals from space that transmit positioning and timing data to GNSS receivers. The receivers then use this data to determine location.
By definition, GNSS provides global coverage. Examples of GNSS include Europe’s Galileo, the USA’s NAVSTAR Global Positioning System (GPS), Russia’s Global'naya Navigatsionnaya Sputnikovaya Sistema (GLONASS) and China’s BeiDou Navigation Satellite System.
What is Narrowband-IoT?
Narrowband-IoT, or NB-IoT as it is shortened, will become a new Low Power Wide Area (LPWA) network, enabling connectivity to GPS/GNSS, 2G, 3G and 4G through existing mobile network infrastructure. It promises to connect devices in rural areas and even the ‘deep indoors’.
LPWA connections allow small packets of data (10s of kbps, realistically) can be transmitted and received incredibly efficiently. This efficiency advantage has been proven to provide 10-year battery lives in some use cases, a necessary requirement where thousands of sensors, detectors, gauges and other devices will be needed to create a truly connected urban environment.
What is LoRa?
LoRa Technology offers a very compelling mix of long range, low power consumption and secure data transmission. Public and private networks using this technology can provide coverage that is greater in range compared to that of existing cellular networks. It is easy to plug into the existing infrastructure and offers a solution to serve battery-operated IoT applications.
LoRaWAN is a protocol specification built on top of the LoRa technology developed by the LoRa Alliance. It uses unlicensed radio spectrum in the Industrial, Scientific and Medical (ISM) bands to enable low power, wide area communication between remote sensors and gateways connected to the network. This standards-based approach to building a LPWAN allows for quick set up of public or private IoT networks anywhere using hardware and software that is bi-directionally secure, interoperable and mobile, provides accurate localization, and works the way you expect.
What is SIGFOX?
Launched in 2012, SIGFOX is the world’s leading provider of connectivity for the Internet of Things.
The SIGFOX company is deploying a global network that provides two-way, out-of-the-box, energy-efficient and cost-effective connectivity to Internet of Thing devices.
Currently (as of October 2015) deployed in the U.S. and 10 European countries and registering over 5 million devices, SIGFOX’s network is the only IoT-dedicated connectivity solution commercially available that guarantees a high level of service and reliability on an international scale.
What is RoHS?
RoHS stands for Restriction of Hazardous Substances.
RoHS, also known as Directive 2002/95/EC, originated in the European Union and restricts the use of specific hazardous materials found in electrical and electronic products. All applicable products in the EU market after July 1, 2006 must pass RoHS compliance.
What are the restricted materials mandated under RoHS?
The substances banned under RoHS are lead (Pb), mercury (Hg), cadmium (Cd), hexavalent chromium (CrVI), polybrominated biphenyls (PBB), polybrominated diphenyl ethers (PBDE), and four different phthalates (DEHP, BBP, BBP, DIBP).
What is REACH and how is it related to RoHS?
REACH is a general regulation and stands for Registration, Evaluation, Authorization, Restriction of Chemicals, and addresses the production and use of chemical substances and their potential impact on human health and the environment. REACH is monitored by the ECHA and deals with 38 chemicals currently.