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Radio waves and RF Frequencies
Using Radio Signals as a Data Transmission Medium Now that you've become a little more familiar with what radio signals are and how they can be used in a public band of frequencies without creating general chaos, let's take a look at how those radio signals are used to create a network transmission medium. Computer networks use variations in electrical current to transmit data from one computer to another. While each type of cable (coaxial, thin coaxial, and unshielded twisted pair) has its own electrical properties, there is a commonality in how the electrical signals are transmitted from one network card to another using these media. Using a telephone "line," whether analog or digital, adds a little complexity to the process, but not a lot. However, when using fiber optical cable, which uses light waves as a medium, and radio signals, which use radio waves as a medium, the process is a bit more complex. What is a Microwave Radio Transceiver? Microwave Radio Transceivers  To create a computer network connection over radio waves, two puzzle pieces are needed. First, a network device such as a bridge or a router is needed. The network bridge/router handles the data traffic. It routes the appropriate data signals bound from the computer network in one building to the network at the other end of the radio connection. Second, a radio transmitter and receiver, commonly called a transceiver, is required. The radio transceiver handles the radio signal communications between locations. The interesting part of this marriage of technologies is that radios have always dealt with electrical signals. The radio transmitter modulates, or changes, an electrical signal so that its frequency is raised to one appropriate to radio communications. Then the signal is passed on to a radio antenna. We'll discuss the work of antennas more in the section "How the Antennas Work."At the other end of the transmission, the receiving portion of the radio transceiver takes the radio signal and de-modulates it back to its normal frequency. Then the resulting electrical signal is passed to the bridge/router side for processing by the network. While the actual process of modulation/demodulation is technical, the concept of radio transmission is very simple. Likewise, when a response is sent back to the originating site, the radio transceiver "flips" from reception mode to transmission mode. The radio transceivers at each end have this characteristic. Transmit-receive, transmit-receive. They change modes as many as thousands of times per second. This characteristic leads to a delay in communications called latency . It is idiosyncratic to radio communications and negativelyaffects data throughput. See the section "Throughput vs. Data Rates" below for more information. Building an ISP Guide: href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp1.html">Building an ISP Overview href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp2.html">Broadband Wireless P2P & P2MP href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp3.html">What is a Wireless Internet Service Provider? href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp4.html">Types of availalbe Broadband Wireless Technologies href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp5.html">Radio waves and RF Frequencies href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp6.html">Spread Spectrum and Frequency Hopping Technology href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp7.html">Using Radio Signals as a Data Transmission Medium & Microwave Radio Transceivers href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp8.html">Microwave Wireless Antennas - How they work & types href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp9.html">Data Cables, Lightning Suppression, Tower Structures and Building ISP href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp10.html">Throughput vs. Data Rates & Summary of How RF & Wireless NetworkWorks href="https://www.tech-ware-tips-startup-internet-business.com/buildinganisp11.html">Planning and Building a Turnkey Broadband Wireless Internet Service Provider Solution ISP href="https://www.tech-ware-tips-startup-internet-business.com/wisp-business.html">
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