Microwave technology has applications in all three of the wireless
networking scenarios: LAN, Extended LAN, and Mobile networking. Microwave
communication can take two forms:
Terrestrial Microwave Links (Earth Links)
Satellite Microwave Links (Satellite Stations)
The frequencies and technologies employed by these two forms are similar, but as you'll see, distinct differences exist between them.
Terrestrial Microwave
Terrestrial microwave communication employs Earth-based transmitters and receivers. The frequencies used are in the low-gigahertz range, which limits all communications to line-of-sight. You probably have seen terrestrial microwave equipment in the form of telephone relay towers, which are placed every few miles to relay telephone signals crosscountry. Microwave transmissions typically use a parabolic antenna that produces a narrow, highly directional signal. A similar antenna at the receiving site is sensitive to signals only within a narrow focus. Because the transmitter and receiver are highly focused, they must be adjusted carefully so that the transmitted signal is aligned with the receiver. A microwave link frequently is used to transmit signals in instances in which it would be impractical to run cables. If you need to connect two networks separated by a public road, for example, you might find that regulations restrict you from running the cables above or below the road. Or, even you may connect the networks with cables, intruders can detect the signal even from outside the building and on the road. The safety can also be in danger by connecting with cables. Eavesdropper cannot detect fiber optic cable, how about if someone breaks the fiber optic any time in the night. Only joining the broken fiber-optic may increase your expenditure. In these practical jokes, a microwave link is an ideal solution. Some LANs operate at microwave frequencies at low power and use nondirectional transmitters and receivers. Network hubs can be placed strategically throughout an organization, and workstations can be mobile or fixed. This approach is one way to enable mobile workstations in an office setting. In many cases, terrestrial microwave uses licensed frequencies. A license must be obtained from the FCC, and equipment must be installed and maintained by licensed technicians. Terrestrial microwave systems operate in the low-gigaherts range, typically at 4-6 GHz and 21-23 GHz, and costs are highly variable depending on requirements. Long-distance microwave systems can be quite expensive but might be less costly than alternatives. (A leased telephone circuit, for example, represents a costly monthly expense). When line-of-sight
Terrestrial Microwave Links (Earth Links)
Satellite Microwave Links (Satellite Stations)
The frequencies and technologies employed by these two forms are similar, but as you'll see, distinct differences exist between them.
Terrestrial Microwave
Terrestrial microwave communication employs Earth-based transmitters and receivers. The frequencies used are in the low-gigahertz range, which limits all communications to line-of-sight. You probably have seen terrestrial microwave equipment in the form of telephone relay towers, which are placed every few miles to relay telephone signals crosscountry. Microwave transmissions typically use a parabolic antenna that produces a narrow, highly directional signal. A similar antenna at the receiving site is sensitive to signals only within a narrow focus. Because the transmitter and receiver are highly focused, they must be adjusted carefully so that the transmitted signal is aligned with the receiver. A microwave link frequently is used to transmit signals in instances in which it would be impractical to run cables. If you need to connect two networks separated by a public road, for example, you might find that regulations restrict you from running the cables above or below the road. Or, even you may connect the networks with cables, intruders can detect the signal even from outside the building and on the road. The safety can also be in danger by connecting with cables. Eavesdropper cannot detect fiber optic cable, how about if someone breaks the fiber optic any time in the night. Only joining the broken fiber-optic may increase your expenditure. In these practical jokes, a microwave link is an ideal solution. Some LANs operate at microwave frequencies at low power and use nondirectional transmitters and receivers. Network hubs can be placed strategically throughout an organization, and workstations can be mobile or fixed. This approach is one way to enable mobile workstations in an office setting. In many cases, terrestrial microwave uses licensed frequencies. A license must be obtained from the FCC, and equipment must be installed and maintained by licensed technicians. Terrestrial microwave systems operate in the low-gigaherts range, typically at 4-6 GHz and 21-23 GHz, and costs are highly variable depending on requirements. Long-distance microwave systems can be quite expensive but might be less costly than alternatives. (A leased telephone circuit, for example, represents a costly monthly expense). When line-of-sight
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