What is Radio Frequency Communication

Radio frequency (often abbreviated as, RF), can be described as any frequency within the electromagnetic spectrum with radio wave propagation that lie in the range extending from about 3 kHz to 300 GHz; this includes the frequencies that are used for communications or the radar signals. That said, you should know that RF generally refers to electrical rather than the mechanical oscillations.

RF communication utilizes radio waves rather than wires to exchange signals, and this is where the term “wireless communication,” comes from. RF modules generally use frequencies to distinguish the different radio signals, therefore, in order for the RF modules to communicate, they have to be operating on the same exact frequency. That said, you should know that radio frequency is normally measured in units known as hertz (abbreviated as Hz), which represent number of cycles/second when the radio wave(s) is transmitted. 1 hertz (Hz) equals 1 cycle/second, and 1 megahertz (abbreviated as, MHz) equals 1 million cycles/second.

A radio frequency (RF) signal basically refers to the wireless electromagnetic signal that’s utilized as a form of communication, when talking about wireless electronics. As mentioned earlier, radio waves are a type of electromagnetic radiation which have identified radio frequencies which usually range from about 3Hz to 300 GHz. Not every radio wave is the same; they can be small or big, or they can be far apart or close together. On the radio stations we normally listen to, every station uses waves which are on a slightly different frequency from the other stations. Whenever you happen to switch from one radio station to another, your radio picks up and then plays waves of that particular frequency.

Frequency normally refers to the oscillation rate of the radio waves. It can also refer to how close together or far apart the waves are. When the radio waves are too far apart, that is known as low frequency, and when the radio waves are close together, that is known as high frequency. That said, you should know that radio frequency propagation happens at speed of light, and doesn’t need any medium (such as air) in order for it to travel. Radio frequency waves occur naturally from lightning, the sun flares, and even from stars which radiate radio frequency waves as the get older. However, people usually communicate with man made radio waves which oscillate at various select frequencies.

The man made radio frequency waves are produced by oscillating current for a certain number of times, and radiating it off the conductor (which is referred to as the antenna), into an empty space (this is the space that’s occupied by air and not the outer space), as electromagnetic radio waves. The RF signals are received and sent using conductors via the phenomenon that’s called the skin effect, where radio frequency current latches itself and then flows through the conductors’ surface; this effect is actually the basis and the core of radio technology.

The best thing about RF communication, is that it’s omnipresent (that is to mean it’s all around us). It plays a crucial role in many of the communications systems which we depend on a daily basis, such as fire and police radio systems, TV and radio broadcasts, and satellite communications. Cordless phones, cellphones, Wireless internet (Wi Fi), and Bluetooth also operate in the radio frequency spectrum. In addition to that, there are other appliances outside of the communications field that use RF. They include; microwave ovens, garage door openers, among others. Some wireless devices such as TV remote controls, cordless computer mice, computer keyboards, and even 2 way radios also operate using RF frequency.

2 way radios are based on the RF frequency and they perform group communication using minimum radio frequency channel resources. This is to mean that if all the users are in the same location or area (most of the time), you will only need a single channel resource in order to talk to them. By using RF, 2 way radios have the capability of facilitating “one to many” group communication (which is also known as a group call), very efficiently. By efficient, I mean that 1 user can communicate/talk to 1, 5, 10, 100 or even 1000’s of users at a go. The 2 way radio user doesn’t need to keep on repeating the same message if he/she needs to convey to many users.

How To Choose a Radio Earpiece

When choosing a radio earpiece, there are several factors that should be considered. A radio earpiece should not only aid in communication it should also protect the user’s ear against cumulative ear damage that may eventually result in ear loss. Below are the factors that you should consider when buying a radio earpiece;

1) Clarity of communication

The most important reason as to why you have a radio is for clear communication and this is what your radio earpiece should enhance. Although there are several radio earpieces out there , many of them use bone conduction when transmitting the user’s speech meaning that they heavily rely on vibrations of one’s skull as they talk. This does not help much in ensuring that the communications are clear especially when one is on the move.

You should therefore go for a system whose in-ear microphone does not use bone conduction and this will enhance the sound clarity. Such a system can even transmit speeches when one is whispering and this comes in handy especially when in an environment where secrecy is very crucial.

2) Comfort

It is very important to select a system that you feel comfortable with most importantly when you are to wear it on your head. Note that, you will probably be wearing the gear for long hours and that is why it should be of lightweight and should not in any way interfere with your eye wear or helmet.

Avoid heavy, sweaty and coiled tube earpieces that are very uncomfortable and will cause ear fatigue. Instead, go for a radio earpiece whose microphone is built into the earbud itself. Such earpieces come in various shapes and sizes and can even be customized to fit the specific needs of a user. Note that, military-grade materials are specifically designed to be of lightweight.

3) Durability

Durability is a very important factor that should be considered when choosing a radio earpiece. You obviously don’t want to be wasting your time and money going back to look for another earpiece just because the one you chose did not last. This is why it is very important to select a system that is durable and has been tested for rugged use of a soldier or a SWAT officer. Go for one whose manufacturer is experienced in manufacturing earpieces that can withstand water, dirt, shock and even extreme temperatures.

4) Ease of use

Your radio earpiece should be easy to use because you can’t afford to mess up with the push-to-talk or the on & off buttons especially when on the move. Your gear should immediately fit into your actions with minimum effort. Look at the operational and the ergonomic features of the various radio earpieces and make sure that all its features are both of the right sizes and in the right places.

5) Hearing protection

Claims related to hearing loss and its related disabilities is on the rise among police & military veterans and this has led to the need for hearing protection for officers. Note that, hearing loss occurs cumulatively over time and it is irreversible. This is in addition to the fact that it has been associated with cognitive decline and that is why even the minor hearing loss can have a huge impact in the course of time. Select a radio earpiece that not only ensures effective communication, but also the hearing safety of the user.

6) Situational awareness

An earpiece is basically meant to keep you focused and keep your hands free. You should be aware of what is happening in their surrounding and that is why a radio earpiece should allow one to hear sounds that are outside, to stay alert with their surroundings.

In order to have full communications (just like one would have without anything in their ears), it is wise to choose a radio earpiece that has an external microphone. There are systems that even enable you to adjust volume of the external microphone and this ensures that you are aware of the happenings in your surroundings.

7) Modularity & Compatibility

There are several systems that are available out there and you should look for one that fits your requirements. As mentioned above, some of them can be customized to fit an individual user’s specific needs so you can never run out of options.

A radio earpiece that has a modular connector is good as you can change it to match even a different radio without having to replace the entire system. Some systems can even go with both earbuds and over-the-ear earpieces so depending on your needs, select the appropriate system.

8) Affordability

Many years ago radio earpieces cost £100 and upwards, these days you can get a D-ring earpiece for less than £15 and an acoustic tube for about £25. Bone conductor earpieces that were previously and expensive piece of technology, can be yours for about £40.

MIT’s new method of radio transmission could one day make wireless VR a reality

VR is the Buzz word for this year, every technology company clambering to get their headset out on to the market. Much of the market needs to catch-up though, the power of home computing needs to improve and removing the inevitable extra cabling and wires that come with current headsets. Luckily this article is about the future technology of VR headsets, see what we can expect as this technology grows.

If you want to use one of today’s major VR headsets, whether the Oculus Rift, the HTC Vive, or the PS VR, you have to accept the fact that there will be an illusion-shattering cable that tethers you to the small supercomputer that’s powering your virtual world.

But researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) may have a solution in MoVr, a wireless virtual reality system. Instead of using Wi-Fi or Bluetooth to transmit data, the research team’s MoVR system uses high-frequency millimeter wave radio to stream data from a computer to a headset wirelessly at dramatically faster speeds than traditional technology.

There have been a variety of approaches to solving this problem already. Smartphone-based headsets such as Google’s Daydream View and Samsung’s Gear VR allow for untethered VR by simply offloading the computational work directly to a phone inside the headset. Or the entire idea of VR backpacks, which allow for a more mobile VR experience by building a computer that’s more easily carried. But there are still a lot of limitations to either of these solutions.


Latency is the whole reason a wireless solution hasn’t worked so far. VR is especially latency-sensitive, along with the huge bandwidth requirements that VR needs to display the level of high-resolution video required for virtual reality to work. But the MIT team claims that the millimeter wave signals can transmit fast enough to make a wireless VR headset feasible.

The issue with using millimeter wave technology is that the signal needs a direct line of sight, and fares poorly when it encounters any obstacles. MoVR gets around this by working as a programmable mirror that can direct the direction of the signal to the headset even while it’s moving to always make sure the signal is transmitting directly to the headset’s receivers.

For now, the MoVR is simply a prototype, with the team hoping to further shrink down the system to allow for multiple wireless headsets in one room without encountering signal interference. But even as a proof-of-concept, it’s an interesting perspective on how virtual reality could one day work.

Far offshore windfarms present communications challenges

This is an interesting article debating the different types of communication that can be used over a long distance, and as they distance moves further and further, the different types of communication drop off or become part of an infrastructure. As engineers battle with this problem, knowledge of how radio frequencies and applications becomes paramount.

As offshore windfarms are built further and further from land, alternatives to conventional VHF communications are going to be required

A cornerstone of any major project is clear communication between all parties. As we move windfarm construction further offshore, maintaining efficient voice and data communications becomes essential. With many projects now being constructed beyond the range of VHF radio and cellular telephone, such as a Gemini or Dudgeon offshore windfarms, crew transfer vessel (CTV) operators and their clients are experiencing challenges achieving practical and affordable offshore communications. My experience on two far offshore projects in the last 15 months has shown that creative thinking can work together with existing equipment such as TETRA radio to reduce the risks and stress that poor communications can generate.

Communication solutions on offshore windfarms depend on the phase that the operation is in, the size of the project and the distance from shore. Many smaller, older windfarms rely on VHF radios to communicate between shore and vessel and shore/vessel and work team on the turbines. However, VHF is limited in range being a line-of-sight system, and the signal has trouble penetrating structures such as wind turbines due to the Faraday cage effect. Conventional cellular telephone coverage is also possible on nearshore sites, with some windfarms installing a cellular mast within the windfarm. Vessels at anchor off the Dutch port of IJmuiden can thank the windfarm industry for good connection when waiting for a pilot if they have contracts with the provider KPN.

When moving further offshore, luxuries such as a cellular mast will not be installed during the construction phase, and it is most likely that VHF radios will not be sufficient. It is common for the developer to install a TETRA radio network – similar to those used by national emergency response services such as police and fire departments.

TETRA, or terrestrial trunked radio as it is properly termed, is a secure network allowing one-to-one, one-to-many and many-to-many communications. This means that the marine controller can speak directly and privately to one party or to the entire offshore spread depending on what is needed. It transmits on a lower frequency than VHF so covers a greater range. This still is not enough to cover the distances experienced on far offshore windfarms. If multiple base stations are used, each base station can then automatically rebroadcast a message thus expanding the network coverage. On a recent construction project, it was found that there were communications blackspots in the area of the sea passage from the base port to the site. This was later eliminated by fitting full base station units rather than just handheld transceivers on the CTVs. The CTVs then became vital links in the communications network and ensured the blackspots were reduced or eliminated altogether.

TETRA has many other advantages, including the ability to penetrate the tower of a wind turbine, and calls are not dropped when moving between base station carriers due to the network configuration. This is especially important if vessel-carried base stations are relaying far offshore. The network is also secure, which ensures that commercially sensitive information cannot be intercepted. With the one-to-one mode, it also means that managers can have detailed conversations on sensitive subjects.

However, anecdotal information received from vessel crews in the field appear to indicate that TETRA, although a good system, is not foolproof. One vessel master reported that, after 15 months on site, they still had blackspots with TETRA and sometimes have to use the cell phone application WhatsApp to request that turbines be started or stopped so that he can land a team.

TETRA does not solve the operational problems experienced by vessel-operating companies who require frequent voice and data communication with the CTVs to ensure a smooth delivery of service. As most sites far offshore are outside of cell phone coverage and clients demand that daily reports are issued on time, creativity is needed. There is a simple solution that could solve all of the communication problems far offshore – installing VSAT satellite communications on each CTV, which allows instant telephone and data transfer.

However, the practicalities of chartering in today’s windfarm industry eliminates this option, as the client will not want to pay for installation and operation, and a vessel owner cannot afford such a luxury. Charterers therefore need to make a decision: either they assume responsibility and the costs for practical workable satellite communications on their vessels or look for practical alternative solutions to deliver what is needed far offshore.

One practical solution to maintain communications between the marine co-ordination centre and vessels is to step back a generation and use medium frequency/high frequency single side band radios, which are common equipment on larger CTVs and is standard on service operation vessels (SOVs) or installation vessels.

When used in conjunction with the digital selective calling (DSC) function of the GMDSS standard, voice communications can be maintained at long distance without operating cost. Unfortunately, current guidance for the marine co-ordination in windfarms as found in the G9 Good practice guideline: The safe management of small service vessels used in the offshore wind industry does not yet consider marine co-ordination and communications in far offshore windfarms.

Another practical solution to improve data communication is to install powerful WiFi antennas on the decks of SOVs and other major offshore assets to allow CTVs to have internet access when they are in close proximity. CTVs can then download passenger manifests and weather reports and upload the daily progress report and synchronise planned maintenance and email systems.

CTVs spend considerable time in close proximity to the SOV during passenger transfer, bunkering or waiting for the next assignment, and it is relatively easy to set up the computers to connect and synchronise without operator input, thus reducing the risk of distraction. SOVs should be designed with space for CTV crews to use as a secure office so that laptops can be left connected to the network. In this way, crews can have two computers and prepare work when on shift, transfer via a data stick and upload when they go off shift.

One of the most effective tools that we have identified is WhatsApp, which seems to require very low signal strength to connect and transfer brief messages. On recent projects, we have found that most vessel/office communication occurs in this medium, including fault finding and incident reporting and investigation. Crews have found it quicker to video a CCTV system playback and send via WhatsApp than download the CCTV video and send it via a file transfer service. As synchronising an electronic planned maintenance system offshore is very time consuming, our superintendents have taken to sending the worklists via WhatsApp to the vessels who then confirm back with text or images when a job is complete. The superintendent then does the PMS administration from their office with the advantage of high speed network connections. Experience with WhatsApp has led me to believe that agile, low data applications will form part of the future of offshore communication.

Far offshore projects have moved from planning and dreaming to reality. However, effective and cost-efficient communication solutions have not moved with them. Like most challenges with far offshore windfarms, there is no single solution, but experience has shown that, with creativity and flexibility, projects can communicate with their teams and operators can manage their vessels.

Better equipment earlier on in the construction phase, such as MF/HF radios in the MCC and on the vessels, TERA base stations on the vessels and open deck WiFi on construction assets will all assist in improving safety and reducing stress while ensuring that unnecessary costs are not incurred.

London Gatwick Airport deploys new radio system from Motorola Solutions

Back in the day, around 2006, the Heathrow and Gatwick radio systems were the envy of many, many businesses, a cutting-edge Motorola analogue trunking system with individual and group setup, that could broadcast messages out across the site or talk to individual radios, something that is taken for granted these days with our digital systems. The Gatwick system has been upgraded and been given the digital touch.

US-based Motorola Solutions, along with its authorised channel partner Servicom, has debuted its new digital mobile radio (DMR) system, Mototrbo Capacity Max, at London Gatwick Airport.

Designed to provide enhanced voice and data communications, the newly installed system connects 1,300 people in the airport’s airside and groundside teams.

Mototrbo Capacity Max will also double the capacity of Gatwick’s current analogue network.

Various applications, such as TRBOnet PLUS and iBeacon, were given along with Mototrbo Capacity Max to improve its data performance.

TRBOnet PLUS is a dispatcher application that allows voice recording, mapping and event logging in the control room, while the iBeacon indoor positioning application sends alerts to individual radios based on location.

Gatwick Airport IT project manager Simon Telling said: “We chose Motorola Solutions’ Mototrbo Capacity Max system not only for how resilient and secure it is, but because of the flexibility it offers us now and into the future.

“We have experienced significant growth over the past decade and we are now approaching the limits of our previous analogue system.

“Migrating to scalable, digital communications will double our capacity and bring new capabilities that will help us improve efficiency and safety for staff, retail partners and passengers across the airport.”

The new Motorola solution will also enable Gatwick’s central controllers to send off the closest employee to an incident, saving time.

The airport recorded more than 4.6 million in passenger traffic in July.

Source – http://www.airport-technology.com/news/newslondon-gatwick-airport-deploys-new-radio-system-from-motorola-solutions-5021249