Radio Waves are essentially invisible signals that can be received by various different devices. Radio waves are one of the longest wavelengths in the electromagnetic spectrum and have a whole variety of uses other than allowing you to listen to music on the radio. The recent advances in technology have meant that radio signals can now be detected by mobile phones, television sets and online.Heinrich Hertz proved the existence of radio waves in 1880 and since this discovery the technology has dramatically advanced as our understanding of how radio waves work has increased. It is possible to tune your radio to a specific frequency so that you can receive certain radio broadcasts, however not all are available everywhere. A small radio station like Demon FM will only be accessible within about 10 miles of DMU whereas a much larger station like Radio 1 will be available over a much larger area.The ionosphere can be found in the earths atmosphere and can allow radio waves to travel much larger distances at night. This is possible because at night radio waves can reflect off the ionosphere and bounce to and from earth meaning they can travel much further. This can sometimes mean stations that you would not normally be able to receive from your home are accessible at night.
Radio waves play a huge role in everyday life, however many people do not realise how much we depend on them. Probably the most important use of radio signals is communication, as they have dramatically changed the way we communicate with each other in day to day life. A prime example would be the mobile phone, as most people own a mobile phone that uses radio waves to send and receive messages. In addition to this radio waves are also used to operate essential radio systems for planes, satellite navigation systems and police radio’s, which is continually improving our way of life and playing a majorly important part in society today.Without the use of radio waves technology would not have advanced as quickly as it has recently. The common use of radio waves has allowed us to communicate with one another much more efficiently and over huge distances. The ability to send files, pictures and music to one another has meant that a lot of media has been shared around at a much faster pace, an example being viral videos or breaking news.This technology is not only important socially but also for military reasons, as satellites and radio systems are used to communicate on the battlefield. The army, air force and navy all use radio waves in some aspect of their technology to communicate with one another, which can in turn save lives. With the continuing development of technology radio waves are surely going to be incorporated in to another useful item or communication method that will improve our lives once more.
Mobile Phones are one of the main devices that depend on radio waves to operate and are commonly used all over the world. In order for mobiles to work a telephone network is needed. Radio base stations provide this service by transmitting signals from an antenna to mobiles so that messages can be sent and received. Mobile networks are split up in to ‘cells’ that each have a base station. The major cities usually have smaller cells as each base station is having to cope with large numbers of calls because of the dense population. This is completely different to the countryside where one cell may be used for a much larger area.In order for a call to be made from one mobile to another a radio base station is required. This is more informally known as having ‘signal’ and the closer you are to one of these stations the better your signal. To make a call the mobile will send radio signals to a base station, which will then send a signal to the nearest base station of the person receiving the call. This signal will then be sent to the phone of the person being called so they can receive the incoming call. Whilst on the move in a car or on a train the base station will switch as you move from cell to cell to avoid cutting you off mid conversation.
Radio waves are also used in another huge medium, television. Millions of people watch television everyday so it’s a big business with very high demand for channels and cable T.V. This means that thousands of T.V stations are required to satisfy this demand and broadcast the radio waves that are used to transport the signal to peoples homes. The radio waves will carry signals that are transmitted from the stations to your T.V set antenna, which will then be displayed on the screen in the form of an image made up of pixels. There are multiple channels available in the modern day so this shows how much we have advanced since T.V was first invented.Cable companies provide most of the channels by using satellite dishes and antennas to receive the T.V stations transmissions, which they then sell to customers for the luxury of being able to view the channel in their home. Television signals are transmitted using Ultra high frequency, which is approximately 470 – 582MHz. In order to receive this television signal you need a satellite dish that will pick up the radio waves broadcast from T.V stations and convert the information in to an image on your T.V screen.
WiFi is a reasonably new technology that has made it possible to use radio waves to produce high speed wireless internet. This internet connection is produced by sending a radio signal from a computer antenna to a wireless router which is designed to convert this information in to an internet connection. Once the router has converted the signal to a connection it is sent to the computer using an Ethernet cable so the user can connect to the internet. WiFi is also used for radio communication because of its high frequency which allows more data to be transmitted. These WiFi radios transmit at a frequency of 2.4 GHz or 5 GHz which is significantly higher than that of other technologies that use radio waves.WiFi is now widely used because of its convenience and simplicity and is common in most households. The use of radio waves allows multiple people to access the same wireless router at once, however if too many people use the network at once then its possible to lose connection.
The military use radio waves for a variety of important tasks that are extremely helpful in a war situation. The radar is the first example of the military exploiting this useful technology. The radar was first used in World War 2 and uses radio waves to locate objects and provide certain details about them. These details can be extremely valuable and provide information on how far away the object is from the transmitter, how fast the object is going and even the height. This is particularly useful for detecting missiles and other enemy forces that may be close by, which gives some warning as to when an attack might happen or where enemies may be hiding. In order to locate objects radio waves are transmitted, which will then reflect back off anything it encounters. The reflected waves will then be received by the antenna which will display the object on a screen or monitor. This allows the military to pin point the locations of certain objects whether they are in the air, in space or on the ground. This technology is used in multiple devices by the military ranging from marine radars to antimissile defence systems.
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