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    RF (Radio Frequency)

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    About RF (Radio Frequency)

    The theme this month is RF (Radio Frequency) and it comes from a suggestion from neuromodulator.  Your project can be anything that involves or explores RF including circuits, antennas, SDR (Software Defined Radio), ham radio, modulation/demodulation, RADAR (acronym for RAdio Detection And Ranging), and more!  Your projects can involve applications related to RF including robots, data acquisition projects, data transfer, automation, remote control, wireless sensor networks, cellular IoT, health, object detection, and more!  The most innovative RF project wins a grand prize package that includes a Spectrum Analyzer and a $200 Shopping Cart!  Three First Place Winners Win a Handheld Oscilloscope plus a $100 Shopping Cart!  Be sure to check out Tech Spotlight: IoT RF Protocols for a full range of RF protocols that you can use for your project. Your projects can use any combination of amplifiers, modulators, transmitters, antennas, coaxial cables, detectors, and more.  RF refers to electromagnetic radiation at the lower end of the electromagnetic spectrum (EM) with a frequency range of 3kHz to 300 GHz. It is part of the invisible portion of the EM spectrum.  The presence and characteristics of RF such as frequency, wavelength, amplitude require specialized test equipment such as spectrum analyzers and signal-level meters. All known transmission systems work in the RF spectrum range including analog radio, aircraft navigation, marine radio, amateur radio, TV broadcasting, mobile networks and satellite systems. The VHF (very high frequency) band, which ranges from 30-300 MHz, is primarily used for FM radio, TV broadcasts, and amateur radio. A lot of electronic communication devices uses the ultra-high frequency (UHF) band including mobile phones, wireless LAN, Bluetooth, and TV and land radio. Microwaves are a subset of radio waves that operate within the 300 MHz to 300 GHz range and are at the higher end of the RF spectrum. Some RF engineers designate microwaves as beginning at the 1Ghz range and some sources designate microwaves as separate radio waves and microwaves on the RF spectrum but this is arbitrary as they are pretty much the same.

     

    During the  Electromagnetism competition the challenge was to use the  The Force of Electromagnetism: Anything from Solenoids, Motors, to Wireless Transfer!  In the 1860s, James Clerk Maxwell unified the fields of electricity, optics, and magnetism to form the basis of our modern understanding of electromagnetism.  Electromagnetic radiation is a form of energy comprised of oscillating electric and magnetic fields, exhibiting wave like behavior as they zip through space. A change to an electric field will cause a corresponding change to a magnetic field and once created an electromagnetic wave will continue on forever until it is absorbed by matter.  Maxwell thesis, "A Dynamic Theory of the Electromagnetic Field", demonstrated that electric and magnetic fields travel through space as waves and move at the speed of light. Before passing away, James Clerk Maxwell predicted that there should be light with even longer wavelengths than infrared light, which had already been discovered. In 1887 Heinrich Hertz demonstrated the existence of such waves by producing what is now known as radio waves in his laboratory. Hertz's experiment used two rods to serve as the receiver and a spark gap as the antenna.  A spark would jump when the wave was picked up.  His oscillator demonstrated that the velocity of radio waves was equal to the velocity of light, proving radio waves were just another form of light, and how to detach electric and magnetic waves from wire.  His verification that these waves travel at the same speed as visible light, and measurements of their reflection, refraction, diffraction, and polarization properties were a convincing demonstration of the existence of Maxwell’s waves.  For this reason, the frequency of radio waves is measured using units called hertz (Hz), to honor Heinrich Hertz. One hertz is equivalent to one wave per second.  Radio waves are usually measured in kilohertz (a thousand waves per second), megahertz (a million per second) and gigahertz (one billion per second). The radio wave spectrum ranges from approximately 3 kilohertz per second to about 300 gigahertz per second.

     

    During the NFC/RFID competition we challenged you to Build Projects that Use Radio Waves to Communicate Through NFC or RFID!  Both RFID and NFC use radio waves to communicate. RFID systems have an RFID tag or smart label, an RFID reader, and an antenna. The RFID tag uses an integrated circuit and an antenna, which to transmit data to an RFID reader.  Both the RFID readers and the tag must be tuned to the same frequency to communicate.  NFC is a branch of High-Frequency (HF) RFID, both operate at the 13.56 MHz frequency. NFC protocol is used for secure form of data exchange, with an NFC device is capable of being both an NFC reader and an NFC tag. NXP is a co-inventor of NFC along with Sony and supplies the chip that enables your smart phone to make contactless payments, store, and exchange goods securely.

     

    During Smarter World competition we challenged you to Build a Smarter World by Building an Arduino MKR WAN 1300 Project! If you're not familiar with LoRaWAN then you should check out element14 Essentials: IoT II: LoRaWAN for IoT Applications which will introduce you to LPWAN (Low Power Wide Area Network) technologies. LPWAN enables multi-year battery life and allows you to send small amounts of data over long distances a few times per hours in various environments.  LoRaWAN is short for Long Range Wide Area Network and it falls under the umbrella of other LPWAN technology. Other LPWAN technologies include NB-IoT, Sigfox, LTE-M, RPMA, Weightless-P, and LinkLab Symphony Link. LoRa (Long Range) refers to patented wireless data communication technology that is owned by Semtech and LoRaWAN  is the network that LoRa operates on.  LoRa is licensed by Semtech so it is closed and proprietary, while LoraWAN is an open source communication protocol defined by the LoRa consortium (Symphony Link by Link Labs is another open source communication protocol).

     

    LoRa uses Chirp Spread Spectrum (CSS), a wideband Spread Spectrum technology, simply meaning that CSS spreads the transmission over a wide bandwidth. While LoRa is the physical layer that enables the long-range communication link, LoRaWAN defines the communication protocol, as well as, the architecture for the network. The LoraWAN protocol ensures communication is secure and reliable, adding additional headers to the data packets.  It is the most adopted type of LPWAN, promising ubiquitous connectivity for outdoor IoT applications, while keeping network structure and management simple.

     

    Although LoRa is a proprietary property of Semtech, they have licensing deals for LoRa with STMicroelectronics and Microchip.  What gives the Arduino MKR 1300 its LoRa connectivity is a Murata CMWXIZZABZ Type ABZ LoRaWAN module which includes an STMicro STM32L0 series ARM Cortex MO+ 32 bit microcontroller (MCU) and a a Semtech ultra long range spectrum wireless transceiver. The ST32 microcontroller includes AT firmaware that you can interface within your sketches.  Communication with the module can be achieved via UART, SPI, or I2C peripheral interfaces.  The module has pre-certified radio regulatory approval for operation in the 868 and 915 MHz industrial, scientific, and medical (ISM) spectrum in most regions of the world.

     

    Microwave is a subset of RF and it operates Microwave frequencies range between 1 GHz to 1000 GHz include a number of communication applications in both the military and civilian sectors. Military applications include ground and airborne radar, as well as, electronic warfare such as guided weapons and satellite communications. Civilian applications include microwave radar (for police, small boats, intruder alarms, and door openers), direct broadcast satellites (12 GHz), and mobile (1–3 GHz band) as well as cellular (∼1 GHz) communications. In order to make these systems functional, devices that generate, detect, and amplify microwave signals are required. Since the limit for silicon devices is ∼1.5 GHz, GaAs (Gallium Arsenide) devices are preferred above this frequency. Microwave circuits are sometimes difficult to design because conductors such as stray solder act like antennas at these frequencies.

    The 2.4 GHz frequency band offers a low-range, high bandwidth IoT channel. ISM frequency bands typically do not require a license to operate, and therefore they are crowded and noisy and require robust RF mechanisms to tolerate interference. Bluetooth Low Energy frequency is the global, unlicensed Industrial, Scientific, and Medical (ISM) 2.4 GHz short-range frequency band. It is limited between 2400 and 2500 MHz, which includes guard bands of 2 MHz at the low end and 3.5 MHz wide at the high end. The BLE frequency band is divided into 79 channels each with a bandwidth of 1 MHz. Zigbee frequency is based on the IEEE standard 802.15.4 wireless protocol. It operates on one of three unlicensed ISM frequency bands: the global Zigbee frequency channel is 2450 MHz, Zigbee channel frequency in Europe is 868 MHz, and Zigbee United States frequency is 915 MHz.  Wirepas Mesh protocol uses Bluetooth Low Energy radio protocol, so it operates on the global, unlicensed ISM 2.4 GHz frequency band. It is limited between 2400 and 2500 MHz, which includes guard bands of 2 MHz at the low end and 3.5 MHz wide at the high end. The BLE frequency band is divided into 40 channels each with a bandwidth of 1 MHz.

     

    Your project can also involve cellular IoT prototyping, including use of LPWAN technology such as NB-IoT and LTE-M.  You can find out more about this by visiting  Nordic Thingy:91, Cellular IoT Prototyping Platform (Winners Announced: Win a Nordic Thingy:91 for Asking Questions!)  Be sure to also visit the Webinar Briefing & FAQ!  The cellular IoT protocols are fragmented across tens, if not hundreds of frequency bands. Most of them are in the lower spectrum bands. There are 26 NB-IoT frequency bands in total, more than 60% of them are in the sub-GHz frequency range, and less than 30% are above the 1800 MHz. LTE Cat M1 provides more bandwidth compared to NB-IoT, and the LTE Cat M1 spectrum also contains more bands in the higher range. Over 20% of the 29 frequency bands allocated for Cat M1 are in the above 2 GHz range, compared to 15% in NB-IoT. LTE Cat 1 spectrum is nearly evenly split between sub-GHz bands (55%), and bands above the 1.8 GHz (45%).

     

    One exciting use of RF that you should consider for your project is SDR (Software Defined Radio).  Software Defined Radio (SDR) - My First Design is an example of an SDR project from 14rhbTraditional hardware based radio devices limit cross-functionality and can only be modified through physical intervention. By contrast, software defined radio technology provides an efficient and comparatively inexpensive solution to this problem, allowing multimode, multi-band and/or multi-functional wireless devices that can be enhanced using software upgrades. SDR defines a collection of hardware and software technologies where some or all of the radio’s operating functions (also referred to as physical layer processing) are implemented through modifiable software or firmware operating on programmable processing technologies. These devices include field programmable gate arrays (FPGA), digital signal processors (DSP), general purpose processors (GPP), programmable System on Chip (SoC) or other application specific programmable processors. The use of these technologies allows new wireless features and capabilities to be added to existing radio systems without requiring new hardware

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    Your project could also involve projects or experiments that use any number of antennas.  Recently we gave out a bunch of Molex Sample Kits during a Molex webinar: Antenna Essentials: Key fundamentals that impact your RF system and steps to optimize antenna performance.  Sample kits included included Bluetooth / Wi-Fi Antennas; GNSS Antennas; Near Field Communication (NFC) Antennas; Cellular Antennas; Ultra Wide Band (UWB) Antennas, Industrial, Scientific and Medical (ISM) Antennas, and Combo Antennas (Wi-Fi, GPS, ISM, Cellular).  Be sure to also visit the Webinar Briefing & FAQ!  You are free to experiment with antennas or circuits as part of this competition. We had some left over sample kits from the Molex webinar which we have shipped to some members that voted for RF (Radio Frequency) in Project14 | Poll to Decide the November 2019 Competition!  Submit your project idea in the comments below and if your project uses antennas we'll send out a limited number of antennas for projects that use them!

     

    If you're interested in wireless technology and tinkering, ham radio can provide a solid introduction to basic electronics theory and radio communications knowledge.  Your project can be something like ArduTrx - a 2-meter-band ham radio transceiver with Arduino by bernhardmayer or any other idea you can think of.  No License is required to purchase the equipment to make your own ham radio, nor to Monitor (listen) to the many Amateur (Ham) Radio frequencies. However, an FCC License is required to Transmit on Amateur Radio Frequencies in the USA.  According to the  Amateur Radio Group on the community, "According the ARRL, quite a significant proportion of Electronics Engineers also hold Ham licenses. So whether you're an occasional user or avid DX chaser, rag chewer or serious contester, here's a chance to pick a few brains, chew some ideas over or just find out who's who. CW to data, LF to Microwave."  If you do anything involving ham radios or have any questions reach out to members in this group and you should be able to find someone that can help you.

     

     

     

    The electromagnetic spectrum has no theoretical upper or lower limit to frequencies and wavelengths. Wave-like behavior allows electromagnetic radiation to be categorized based on wavelength.  Radio waves have the highest wave lengths and the lowest frequency of the seven types of waves on the electromagnetic spectrum which are ordered in terms of frequency: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.  All are forms of electromagnetic radiation that can best be described as a stream of photons, each traveling in a wave-like pattern, carrying energy and moving at the speed of light.The only difference between radio waves, visible light and gamma rays is the energy of the photons. Radio waves have photons with the lowest energies. Microwaves have a little more energy than radio waves. Infrared has still more, followed by visible, ultraviolet, X-rays and gamma rays.

    RF Frequency Band Overview

    Here is a summary of applications involved with each frequency of the radio spectrum:

     

    Extremely Low Frequency (ELF)

     

    ELF frequencies have only been used in a few man-made communication systems.  This range is highly vulnerable to disturbance and easily gets distorted by atmospheric changes. It is hard to design a system in this rage is challenging because of the larger wavelengths required long antennas which are practically impossible to achieve.  Scientists use this frequency band in seismic studies to understand natural activities in earth’s atmosphere. This frequency range can penetrate seawater, making it useful in communication with submarines.  A few nations have built military ELF transmitters to transmit signals for their submerged submarines.  Huge ground wire antennas (ground dipoles) 15 - 60 km long are driven by transmitters which produce megawatts of power. Frequencies in this range start at 3Hz and go to 3 KHz.

     

    Very Low Frequency (VLF)

     

    The VLF RF frequency range is used for a few radio navigation services, government time radio stations (broadcasting time signals to set radio clocks) and for secure military communication. Since VLF waves can penetrate at least 40 meters (120 ft) into saltwater, they are also used for military communication with submarines. Very low frequency is the starting range of RF and practical radio transmission system which span from 3 KHz to 30 KHz. However, design and implementation of the antenna system is extremely complicated due to the size of these wavelengths. Nevertheless, it has been used in submarines and is still used in time radio station which synchronizes clock signals between two remote locations.

     

    Low Frequency (LF)

     

    LF radio waves exhibit low signal attenuation, making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, they are part of the LF spectrum used for AM broadcasting, known as the "longwave" band. In the western hemisphere, its mainly used for aircraft beacons, navigation (LORAN), information, and weather systems. A number of time signal broadcasts are used in broadcast. The range is from between 30 KHz to 300 KHz. An important property of LF signals is that it gets reflected by Earth’s ionosphere making it suitable for long distance communication. Because of its long wavelength and because it has less attenuation from big terrains like mountains, it is generally referred to as ground waves. Low frequency signals are used by amateur radio operators and it is one of the most important sources of information transfer when other kind of communication sources fails due to natural disaster. Other areas where it is seen include military applications such submarines, RFID tags in near field communication and some low frequency radio broadcasting.

     

    RFID uses only the 125 KHz and 134 KHz (actually, 134.2 KHz) LF range. This range has been in use for RFID tags for animal tracking since 1979 and is the most mature range in use. It is available for RFID use all over the world. The tags in this range are generally called LF tags. They use near-field inductive coupling to obtain power and to communicate with the interrogator. The LF tags are passive tags (no battery and transmitter on the tag) and have a short read range of a few inches. They have the lowest data transfer rate among all the RFID frequencies and usually store a small amount of data. The LF tags have no or limited anti-collision capabilities; therefore, reading multiple tags simultaneously in the IZ is impossible or very difficult. The tag antennas are usually made of a copper coil with hundreds of turns wound around a ferrous core. They are expensive to manufacture, and tags using them are thicker than others at higher frequencies. The LF tags can be easily read while attached to objects containing water, animal tissues, metal, wood, and liquids. LF tags have the largest install base. They are used in access control, asset tracking, animal identification, automotive control, as vehicle immobilizers, healthcare, and various point-of-sale applications (such as Mobil/Exxon SpeedPass). The automotive industry is the largest user of LF tags. For example, in an automobile vehicle immobilizer system, an LF tag is embedded inside the ignition key. When that key is used to start the car, an RFID interrogator placed around the key slot reads the tag ID. If the tag ID is correct, the car can be started. If the ID is incorrect or no tag is found, the car cannot be started

     

    Medium Frequency (MF)

     

    MF is mostly used for AM radio broadcasting, navigational radio beacons, maritime ship-to-shore communication, and transoceanic air traffic control. Medium frequency was one of the most popular frequency bands since the beginning of wireless radio transmission in the early nineteenth century. MF operates in the range of 300 KHz to 3 MHz.  Design of transmitters, receivers and antenna are relatively less complex than other high frequency transmission bands. MF has been widely using in AM radio transmission, navigation systems for ships and aircraft, emergency distress signals, cost guards and other experimental applications.

     

    High Frequency (HF)

     

    The HF band is a major part of the shortwave band of frequencies, so communication at these frequencies is often called shortwave radio. Because radio waves in this band can be reflected back to Earth by the ionosphere layer in the atmosphere – a method known as "skip" or "skywave" propagation – these frequencies are suitable for long-distance communication across intercontinental distances and for mountainous terrains which prevent line-of-sight communications.[2] The band is used by international shortwave broadcasting stations (2.31–25.82 MHz), aviation communication, government time stations, weather stations, amateur radio and citizens band services, among other uses.  High frequency signals ranges between 3 MHz and 30 Mhz. This frequency band is also known as short wave. It also gets reflected by earth’s ionosphere and it is one of the suitable band for long distance communication. High frequency band is mostly used by aviation industry, near field communication (NFC), government systems, amateur radio operators and weather broadcasting stations.

     

    The high frequency range includes frequencies from 3 to 30 MHz but only one frequency, 13.56 MHz, is used for RFID applications. This frequency is now available for RFID applications worldwide with the same power level. Tags and interrogators using 13.56 MHz are generally called HF tags and HF interrogators. Like LF tags, they also use near-field inductive coupling to obtain power and to communicate with the interrogator. HF tags are passive tags and have a short read range, less than 3 feet. They have a lower data transfer rate than UHF frequencies but a higher data rate than the LF range. HF tags may have anti-collision capability that facilitates reading multiple tags simultaneously in the IZ. Since the read range of many HF tags and interrogators is small, they usually do not implement anti-collision. This reduces the complexity and cost. Some HF tags can store up to 4K of data. HF tags are more mature than UHF tags and many standards are in place.  Inductive coupling used by the HF interrogators uses magnetic flux to power and communicate with the tags. Magnetic flux is omnidirectional (not directional) and therefore it covers the entire area, surrounding its source evenly. That means there are no holes in its density. This makes HF tags an ideal choice for applications such as a smart shelf, for which the entire shelf area needs to be covered with magnetic flux so all the items on the shelf can be interrogated. Other applications of the HF tags include credit cards, smart cards, library books, airline baggage, and asset tracking. Due to the absence of restrictions on the use of the HF frequency and the popularity of smart cards, HF tags are currently the most widely used tags around the world.

     

    Very High Frequency (VHF)

     

    Common uses for radio waves in the VHF band are digital audio broadcasting (DAB) and FM radio broadcasting, television broadcasting, two way land mobile radio systems (emergency, business, private use and military), long range data communication up to several tens of kilometers with radio modems, amateur radio, and marine communications. Air traffic control communications and air navigation systems (e.g. VOR & ILS) work at distances of 100 kilometers (62 mi) or more to aircraft at cruising altitude. In the Americas and many other parts of the world, VHF Band I was used for the transmission of analog television. As part of the worldwide transition to digital terrestrial television most countries require broadcasters to air television in the VHF range using digital rather than analog format. Very high frequency is one of the most commonly used bands, operating at a range from 30 MHz to 300 MHz. VHF frequency is widely used in analog TV broadcasting. FM radio broadcasting at 88 MHz to 108 MHz operates in the VHF frequency band. Air traffic controllers and airline pilots are using frequency between 118 MHz to 137 MHz to communicate. Other uses includes private and business radio stations, medical equipment (magnetic resonance imaging), amateur radio and military applications. It is usually affected by big terrains but it is suitable for short distance communication.

     

    Ultra High Frequency (UHF)

     

    Radio waves with frequencies above the UHF band fall into the super-high frequency (SHF) or microwave frequency range. Lower frequency signals fall into the VHF (very high frequency) or lower bands. UHF radio waves propagate mainly by line of sight; they are blocked by hills and large buildings but the transmission through building walls is strong enough for indoor reception. They are used for television broadcasting, cell phones, satellite communication including GPS, personal radio services including Wi-Fi and Bluetooth, walkie-talkies, cordless phones, and numerous other applications. Ultra high frequency is the most important frequency band for modern wireless communication systems. It begins from the 300 MHz to 3 GHz range and it is extremely complicated to design and implement the system. It has many sub frequency bands, some are restricted and assigned only for particular applications.  It is used in GPS navigation systems, satellites, pagers, Wi-Fi, Bluetooth, television broadcasting, and most importantly GSM, CDMA and LTE mobile transmission.

     

    The ultra high frequency range includes frequencies from 300 to 1000 MHz, but only two frequency ranges, 433 MHz and 860–960 MHz, are used for RFID applications. The 433 MHz frequency is used for active tags, while the 860–960 MHz range is used mostly for passive tags and some semi-passive tags. The frequency range of 860–960 MHz is often referred to by a single frequency of 900 or 915 MHz. Tags and interrogators in this range are called UHF tags and UHF interrogators. The passive and the semi-passive tags in this frequency range use far-field radiative coupling, or backscatter coupling. The UHF tags have a read range of about 15 to 20 feet. All protocols in the UHF range have some type of anti-collision capability, allowing multiple tags to be read simultaneously in the IZ. The new Gen 2 protocol for UHF tags is designed for reading several hundred tags per second. UHF interrogators are usually costlier than HF interrogators, but UHF tags are becoming more economical.  The UHF tag antennas are usually made of a copper, aluminum, or silver deposited on the substrate. Their effective length is approximately 6.5 inches, which is approximately equal to one-half the wavelength of 900 MHz radio waves. The optimum length of an UHF antenna is equal to one-half the wavelength of the carrier wave, though with proper design, the length can be reduced. UHF antennas are thin and easy to manufacture, allowing tags to be very thin, less than 100 mM, making them almost two-dimensional. UHF tags cannot be easily read while attached to objects containing water and animal tissues because water absorbs UHF waves. The UHF tags get detuned when they are attached to metal objects. Separating UHF tags from metal objects or objects with liquid improves performance. UHF tags cannot be read if water or any conductive material is placed between the interrogator antenna and the tags.

     

    Super High Frequency (SHF)

     

    These frequencies fall within the microwave band, so radio waves with these frequencies are called microwaves. The small wavelength of microwaves allow them to be directed in narrow beams by aperture antennas such as parabolic dishes and horn antennas, so they are used for point-to-point communication, data links, and radar. This frequency range is used for most radar transmitters, wireless LANs, satellite communication, microwave radio relay links, and numerous short range terrestrial data links. They are also used for heating in industrial microwave heating, medical diathermy, microwave hyperthermy to treat cancer, and to cook food in microwave ovens. Super high frequency in the range of 3 GHz to 30 GHz can only operate in a line of sight path since any obstruction in-between the transmitter and receiving station will break the communication.  It is commonly used in point to point communication, satellite systems, digital TV broadcasting in Ku band (DTH service – direct to home), Wi-Fi (5GHz channel), microwave ovens and mobile networks. Waveguides are suitable between transmitter and antenna due to higher losses of usual RF cables.  System design is extremely hard in SHF band due to its smaller wavelength and complexity.

     

    The microwave frequency range includes frequencies from 1 to 10 GHz, but only two frequency ranges around 2.45 GHz and 5.8 GHz are used for RFID applications. Almost all microwave tags use 2.45 GHz. Microwave tags are available as passive, semi-passive, and active types. The passive and semi-passive tags use backscatter coupling to communicate with interrogators, and active types use their own transmitter to communicate. Passive microwave tags are usually smaller than passive UHF tags and have the same read range of about 15 feet. The semi-passive microwave tags have a read range of about 100 feet, while the active microwave tags have read range of about 350 feet. Passive microwave tags, due to low demand, are more expensive than passive UHF tags, but they share the same advantages and disadvantages. Only a few manufacturers make this type of tag. Japan is the largest user of passive microwave tags.

     

    Extremely High Frequency (EHF)

     

    Compared to lower bands, radio waves in this band have high atmospheric attenuation: they are absorbed by gases in the atmosphere. Therefore, they have a short range and can only be used for terrestrial communication over about a kilometer. Absorption by humidity in the atmosphere is significant except in desert environments, and attenuation by rain (rain fade) is a serious problem even over short distances. However, the short propagation range allows smaller frequency reuse distances than lower frequencies. The short wavelength allows modest size antennas to have a small beam width, further increasing frequency reuse potential. Extremely high frequency band is the highest in RF frequency spectrum which range between 30 GHz and 300 GHz. EHF is only used in advanced communication systems due to its complex nature and line of sight requirement. EHF is used in radio astronomy and remote sensing (weather analysis). It is suggested for use in high speed internet systems like 5G technology and for future transmission networks due to its large bandwidth availability.

     

     

    Your Chance to Win

     

    Be Original
    Stick to the Theme
    • You could come up with a clever name that make's your project memorable!
      • This project is your baby! Part of the fun of bringing something new into the world is coming up with a name.
    • Your project could introduce something new or that is not commercially available or affordable!
    • If you have an idea for a project that doesn't fit the current theme then submit your idea in the comments section of the monthly poll.
    List the Steps
    Submit Video Proof
    • Provide the steps you took to complete your project (text, video, or images).
      • This could be a step by step how-to-guide, vlog, schematics, coding, napkin drawings, voice narration, or whatever you think will be useful!
    • If it doesn't work that's fine, this is more about the journey than the end product.
    • A short video is all that is required but you can shoot as much video as you like.
    • You are encouraged to be creative and have as much fun as possible!

     

    Your Project Examples

     

    RF (Radio Frequency)
    LoRa MER Week 4: Boat Afloat and New Antenna LoRa GeLo MKR - Long Range Geo-Locator MKR 1300

     

     

    RF (Radio Frequency)
    ArduTrx - a 2-meter-band ham radio transceiver with Arduino Stormtrooper Pi Radio

     

     

     

    Your Prizes

     

    One Grand Prize WinnerThree First Place Winners
    • One Grand Prize Winner Wins Spectrum Analyzer plus a $200 Shopping Cart!
    • 3 First Place Winners Win a Handheld Oscilloscope plus a $100 Shopping Cart!
    Buy NowBuy NowBuy NowBuy Now
    • 9KHz to 1.5GHz spectrum analyzer
    • 150dBm displayed average noise Level
    • 10.4inch TFT LCD display
    • Phase noise of -82dBc/Hz at 1Gz and offset at 10KHz
    • USB host, USB device, LAN, earphone port, REF and VGA ports
    • EMI pre-compliance test kit
    • 100VAC to 240VAC power supply
    • 421mm x 221mm x 115mm (W x H x D) dimension
    • Handheld digital storage oscilloscope
    • Auto-scale function
    • FFT function
    • 20 automatic measurement options
    • USB data transmission supported
    • Rechargeable Li-ion battery (6 hours' backup)
    • Waveform record and replay
    • SCPI supported

     

     

     

    Your Project, Your Ideas!

     

    About Project14
    Directions

    Every month you'll have a new poll where you'll get to decide an upcoming project competition, based on your interests, that will take place a couple of months in advance. Themes are broad in scope so that everyone can participate regardless of skill set.

     

    What are Monthly Themes?

    • Every month (around the 14th of each month) a new theme will be posted on Project14.
    • Submit your ideas (proposals) for your projects to get feedback from the rest of the community.
    • Submit a project entry in the Theme space once you start working on it.

     

    What are Monthly Theme Polls?

    • Every month (around the 14th of each month) there is a project theme poll.
    • Vote on which project competition you want to see for the following upcoming theme.
      • The themes voted on during the previous poll decided the upcoming theme.
      • If you submit an idea for a theme that is not used then it can still be used in a future poll.
    • Themes comments and ideas from the comments section of the project theme poll.

    Step 1: Log in or register on element14, it's easy and free.

    Step 2: Post in the comments section below to begin a discussion on your idea. Videos, pictures and text are all welcomed forms of submission.

    Step 3: Submit a blog post of your progress on your project by the end of the month.  You are free to submit as many blog entries as you like until the beginning of the next theme.

     

    Be sure to include video proof of your project!

     

    Visit:  RF (Radio Frequency) or tag your project blog rfradiofrequencyCH

     

    You have until January 14th End of Day to submit your completed project!

     

    A jury consisting of your peers will judge project submissions!

     

    In the Comments Below:  Let Us Know Your Innovative Project Ideas to Do Around RF (Radio Frequency)!

     

    The Most Innovative RF Project Wins a Spectrum Analyzer Plus a $200 Shopping Cart!