Introduction When we think of radio waves, we assume they are only used for radio and broadcasting. In reality, they are used for many more things , these include mobile phones, WIFI and television . Through this presentation I will discuss the use and importance of radio waves and how they apply to mediums beyond radio broadcasting.
Radio WavesWith regards to the electromagnetic spectrum, radio waves have the longest wavelength. The following diagram represents the wavelength for AM, FM and TV.As you can see from the diagram, AM has the longest wavelength as it isbroadcasted further than TV and AM radio. With AM radio having a widercoverage, this implements issues of quality. The bandwidth is usually around5 kHz, although the human ear has a musical range of 20hz which leads toan imperfect sound when compared to the superior FM radio quality. Havingdiscussed this, it leads me to further research into how radio waves take partin mediums other than radio.
WIFI WIFI uses radio waves in a similar way to how a radio operates. This process involves the computer translating data into a radio signal which is then sent out through an antenna. This signal is then received by a wireless router, which goes through the process of decoding. The router then sends the information via a wired Ethernet cable. A notable difference between WIFI and other radio waves is the amount of data that is transmitted. The frequency transmitted via WIFI is either 2.4 GHz or 5 GHz. With this frequency being relatively high, It allows more data to be transferred. Cell phones and television, in comparison use a lower frequency due to less data being needed for the signal.
Mobile phonesFrom an international perspective mobile phones are referred to as ‘cell phones’. The term ‘cell’ derives from how a mobile phone operates. the function involves a cellular pattern, which is basically a number of areas that are divided into cells. These cells require a base station which make up the network and have both a radio and transmitter tower. In large cities, they can have hundreds of towers set up to keep up with the high demand of mobile phone use.A mobile phone carries little power in terms of transmission, and therefore connects to the nearest transmitter within a base station. It can be noted that in more urban areas it is likely to get a stronger signal , in comparison to rural areas where less base stations are likely to be.
Television The antennae of a television is used to receive the signal, which is found in the form of electronic magnetic waves (like a radio) The television signal is sent in two forms; one is the video which is through AM , and sound can be recieved by either AM or FM signal. On average a TV signal needs a bandwidth of 4 Hz , although a further 2 Hz needs to be acounted for sound. The video signal (separately) then goes through the process of amplitude- modulation along with the sound which is then merged and picked up via the antennae
RadarA radar works through a signal being transmitted, which bounces of an object which is then received by a receiver. Radars use electromagnetic waves and microwavesA radar is divided into a transmitter ,switch, antenna, receiver, datarecorder, processor and output device. The received signal is sent to arecording device , and is later interpreted and presented.
What are the importance of radiowaves ? The significance of radio waves during the 21st century goes far beyond communication. Notably, with new technological advancements such as SATNAV, it is true that we have surpassed the initial intentions of use for radio waves. It is true that radio technology was responsible for overseas connection and led to the speed of receiving transmissions from such a long distance, considerably shorter. Radio waves are relied upon in such fields as the military and aircraft based jobs and serve importance , particularly with regards to AM radio transmissions.
Conclusion The importance of radio waves in modern day is highly depended upon, whether it be for radio or other extensive medias we use radio waves for. Without it, we would suffer in terms of long distance communication and also the luxuries of such things as satellite navigation which is one of many devices that make modern day living so convenient.
References How WIFI works (WWW) Marshall brain and Tracy V. Wilson (2011) ttp://computer.howstuffworks.com/wireless-network1.htmhttp:// www.infoplease.com/ce6/sci/A0860617.htmlUses of radio waves (WWW) Columbia university (2007) How cell phones use radiation (WWW) Marshall Brain, Jeff Tyson and Juila Layton (2011) http://electronics.howstuffworks.com/cell-phone2.htm http://science.hq.nasa.gov/kids/imagers/ems/radio.html Radio waves (WWW) Ruth Netting (2007) Image source- http://science.hq.nasa.gov/kids/imagers/ems/radio.gif http://en.wikipedia.org/wiki/Radio#Video Television radio signal (WWW) (2011) http://www.ig.utexas.edu/research/projects/mars/education/pictures/radar/rad_system.g if Radar diagram (WWW) http://www.ig.utexas.edu/research/projects/mars/education/radar_works.htmHow radars works (WWW) Institutes for Geophysics