Microwave technology can be used for LANs, extended LANs, and mobile computing. It uses either terrestrial (ground-based) links or satellite links. There are three forms of mobile computing: packet-radio networking, cellular networking, and satellite station networking. Terrestrial microwave links employ line-of-sight transmitters and receivers in the low gigahertz range, requiring stations every 30 miles, while satellite links use geosynchronous satellites to relay signals over long distances. Microwave systems offer advantages like no cables and wide bandwidth but have disadvantages like disruption from obstacles and signal absorption.

1. Microwave Prepared by: Devang Bhatti

2. Microwave Microwave technology has applications in all three of the wireless networking scenarios; LAN, Extended LAN and Mobile Computing. Microwave communication can take two forms: Terrestrial (Ground) links Satellite links

3. Mobile Computing Mobile computing is a growing technology that provides almost unlimited range of traveling computers by using satellite and cellular phone networks to relay signal to home network. Mobile computing typically is used with portable PCs or personal digit assistants(PDA) devices.

4. Mobile Computing There are Three forms of mobile computing are as follows: Packet-radio networking Cellular networking Satellite station networking

5. Terrestrial (Ground) links 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 cross country.

6. Terrestrial (Ground) links used for long-distance telephone service uses radio frequency spectrum, from 2 to 40 GHz. parabolic dish transmitter, mounted high used by common carriers as well as private networks requires unobstructed line of sight between source and receiver curvature of the earth requires stations (repeaters) ~30 miles apart

7. Terrestrial (Ground) links Terrestrial microwave systems operate in the low gigahertz 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 transmission is possible, a microwave link is a one-time expense that can offer greater bandwidth than a leased circuit.

8. Terrestrial (Ground) links

9. Satellite links a microwave relay station in space can relay signals over long distances geostationary satellites remain above the equator at a height of 22,300 miles (geosynchronous orbit) travel around the earth in exactly the time the earth takes to rotate

10. Satellite links

11. Satellite Links Applications television distribution a network provides programming from a central location direct broadcast satellite (DBS) long-distance telephone transmission high-usage international trunks private business networks

12. Microwave Advantages No cables needed Multiple channels available Wide bandwidth

13. Microwave Disadvantages Line-of-sight will be disrupted if any obstacle, such as new buildings, are in the way Signal absorption by the atmosphere. Microwaves suffer from attenuation due to atmospheric conditions. Towers are expensive to build