What You Need To Know Review the characteristics of the various network topologies, including their strengths and weaknesses. Review the characteristics of Identify the components involved in wireless communications.
Types of wireless networks The preceding classification is neither complete nor entirely accurate. Many technologies and standards start within a specific use case, such as Bluetooth for PAN applications and cable replacement, and with time acquire more capabilities, reach, and throughput.
In fact, the latest drafts of Bluetooth now provide seamless interoperability with Similarly, technologies such as WiMAX have their origins as fixed-wireless solutions, but with time acquired additional mobility capabilities, making them a viable alternative to other WAN and cellular technologies.
The point of the classification is not to partition each technology into a separate bin, but to highlight the high-level differences within each use case.
Some devices have access to a continuous power source; others must optimize their battery life at all costs. Some applications require always-on connectivity, while others are delay and latency tolerant.
These and a large number of other criteria are what determine the original characteristics of each type of network. However, once in place, each standard continues to evolve: It is not a question of picking, or betting on, just one wireless standard! However, regardless of the specific wireless technology in use, all communication methods have a maximum channel capacity, which is determined by the same underlying principles.
In fact, Claude E. Shannon gave us an exact mathematical model Channel capacity is the maximum information rate to determine channel capacity, regardless of the technology in use. Channel capacity is the maximum information rate C is the channel capacity and is measured in bits per second.
BW is the available bandwidth, and is measured in hertz. S is signal and N is noise, and they are measured in watts. Although somewhat simplified, the previous formula captures all the essential insights we need to understand the performance of most wireless networks.
Regardless of the name, acronym, or the revision number of the specification, the two fundamental constraints on achievable data rates are the amount of available bandwidth and the signal power between the receiver and the sender. Both the sender and receiver must agree up-front on the specific frequency range over which the communication will occur; a well-defined range allows seamless interoperability between devices.
For example, the Who determines the frequency range and its allocation? In fact, due to different government regulations, some wireless technologies may work in one part of the world, but not in others. Different countries may, and often do, assign different spectrum ranges to the same wireless technology.
Politics aside, besides having a common band for interoperability, the most important performance factor is the size of the assigned frequency range.
Hence, all else being equal, a doubling in available frequency range will double the data rate—e. Finally, it is also worth noting that not all frequency ranges offer the same performance. Low-frequency signals travel farther and cover large areas macrocellsbut at the cost of requiring larger antennas and having more clients competing for access.
In addition to having different frequencies, wireless signals can be different in the way they convey information. A wireless signal needs to be modulated--or changed--to send information. There are many types of modulation, and different technologies can use one or more types . The four different types of wireless technologies are satellite signals, radio systems, microwave signals, and infrared. These different types of systems have their own way of transmitting signals and different types of strengths. The four different types of wireless technologies are satellite signals, radio systems, microwave signals, and infrared. These different types of systems have their own way of transmitting signals and different types of strengths.
Certain frequency ranges are more valuable than others for some applications. On the other hand, two-way communication benefits from use of smaller cells, which provide higher bandwidth and less competition.
But what is the history? In the early days of radio, anyone could use any frequency range for whatever purpose she desired. All of that changed when the Radio Act of was signed into law within the United States and mandated licensed use of the radio spectrum.
The original bill was in part motivated by the investigation into the sinking of the Titanic. Some speculate that the disaster could have been averted, or more lives could have been saved, if proper frequencies were monitored by all nearby vessels.
Regardless, this new law set a precedent for international and federal legislation of wireless communication. S ever since, effectively "zoning" it by subdividing into ever-smaller parcels designed for exclusive use.
A good example of the different allocations are the "industrial, scientific, and medical" ISM radio bands, which were first established at the International Telecommunications Conference inand as the name implies, were reserved internationally.
Further, both of these ISM bands are also considered "unlicensed spectrum," which allow anyone to operate a wireless network—for commercial or private use—in these bands as long as the hardware used respects specified technical requirements e. Finally, due to the rising demand in wireless communication, many governments have begun to hold "spectrum auctions," where a license is sold to transmit signals over the specific bands.
Yes, that is billion with a "b. Whether the current allocation process is fair is a subject on which much ink has been spilled and many books have been published. Looking forward, there is one thing we can be sure of: In essence, it is a measure that compares the level of desired signal to the level of background noise and interference.
The larger the amount of background noise, the stronger the signal has to be to carry the information.A wireless network is a computer network that uses wireless data connections between network nodes.
 Wireless networking is a method by which homes, telecommunications networks and business installations avoid the costly process of introducing cables into a building, or as a connection between various equipment locations. . The four different types of wireless technologies are satellite signals, radio systems, microwave signals, and infrared.
These different types of systems have their own way of transmitting signals and different types of strengths. Different types of Wireless Technologies: Due to the easy approach to the networks and also in many appliances of the daily life wireless technologies are of many types and almost all the technologies that are used in the present era for the sake of better working are designed wirelessly.
Of all the types of wireless technology, wireless networking underpins the others, as each can potentially become part of a wireless network.
Personal Area Network (PAN). This covers your immediate working area and you can use it to wirelessly connect your computer, keyboard, mouse and printer. In addition to having different frequencies, wireless signals can be different in the way they convey information.
A wireless signal needs to be modulated--or changed--to send information. There are many types of modulation, and different technologies can use one or more types . A type of low cost, low power and wireless technology which is used for the different purposes at ultra low power is known as Zig bee technology.
Low power radios on the basis of standard personal wireless networking are used by a protocol to enhance the technology.