we're now going to take a look at a few methods of wireless transmission media used in communication systems particularly the styles of microwave satellite radio and infrared the first one we're going to look at is microwave and basically a high frequency signal is sent from big towers ok these towers are known as transponders ok and they're placed about 40 to 50 meters apart okay and the signal is sent directly through line-of-sight from one tower to another so if we're gonna take a look at what this looks like here are our transponders okay and they're all spaced out and then they basically send a signal that is about 40 to 50 kilometers apart okay so if we're going to space them out we need to space them out in that distance and send the actual signal from one transponder to another and that's how it spreads over a wide geographical region okay this type of microwave communication is used by telephone networks internet service providers as well as other companies using remote money for remote monitoring and management the next type we're going to look at is satellite now satellite tries to eliminate the line-of-sight barriers that can often happen kay geographical sites often have buildings and things that get in the way so transponders may not be effective in getting the signal around so what we do is we set up a satellite so we set up our transponders okay and they're still spaced out far apart but we set a satellite up in space and that satellite rotates with the rotation of the earth so it's always kind of in the same geographical location above the earth moving with the Earth's movement when data is sent up to the satellite it is known as an uplink okay and then when the satellite returns that same data back to the earth it's known as a downlink so basically it's the greatest distance we can send a communication signal okay using communication technology next we'll look at radio waves and radio is basically used for our wireless technologies okay we all know radio towers giving out a radio signal to listen to on the radio but also it's used for technologies such as Wi-Fi when we set up our home Wi-Fi networks okay as well as other technologies as RFID okay NFC which we do our tap and go with okay as well as Bluetooth when we pair up our devices okay so if we have a look he's my router and that can act as the center of my radio network it will send out a signal okay and it may allow for my PC to connect with my printer okay it may also allow for my TV to connect with the internet okay so we can build up these wireless networks locally within our house using radio technologies as well as in shopping centers and at mcdonnell's the way they've got their hotspots so that all these different devices can communicate with each other without any type of cabling necessary the final one we're going to look at is infrared okay an infrared basically is the simplest form of communication it's just a line of sight using the infrared laser okay the actual type of light use is a very low frequency okay and it's direct line-of-sight okay your TV remote with your TV uses infrared you basically have to aim the signal directly at the receiver for it to hit and it's usually over a short range okay so we've got to remember that so in order to illustrate this okay here's my TV here's my remote control okay and if I'm gonna make my remote work and communicate with the TV I'm gonna aim it directly at the TV okay it will hit the sensory bar in the corner okay and the TV will respond it will turn on it will do whatever but if there's anything in the way okay the signal will not communicate with the TV and it's easily blocked so that's the main downfall of infrared but it's simple cheap and easy to set up many things still use infrared technology so we've obviously got home entertainment but in intrusion detectors fire detectors medical diagnostic equipment where we are close range okay and we've got direct line of sight from the sender and the receiver so I hope this all gives you a better understanding of the wireless communication mediums that are in existence of microwave technology satellite radio and infrared and basically where and when they're used okay through our communication systems