flexible network architecture. The mobile WiMAX air interfaces use OFDMA for improvement in multiple path interference in nonline-of-sight environ-ment. Its ability to support both line-of-sight and nonline-of-sight connections makes it suitable for ubiquitous services offered in rural and urban areas alike. High speed and symmetrical bandwidth satisfy the needs of individual customers, public administration, and enterprises of all sizes . The technology also provides fast and cheap broadband access to markets that lack infrastructure (fiber optics or copper wire), such as rural and unwired countries. Currently, several companies offer proprietary solutions for wireless broadband access, many of which are expensive because they use chipsets from adjacent technologies, such as 802.11. Early field experiments in various countries confirm that expectations in terms of coverage, performance, and usage scenarios are indeed justified. WiMAX has changed the scenario of wireless broadband from proprietary solutions to a standards-based industry. It supports fast Internet access, high-quality audio and video communications, education, entertainment, telemedicine, telemetering, and telesurveillance. WiMAX supports personal broadband services on both fixed and mobile settings because of its high spectral efficiency and wide channelization as well as the advanced antenna technologies. This flexibility in providing both fixed and mobile access within the same infrastructure is unprecedented among wireless technologies, which are typically optimized for either mobile or fixed access.
Figure 1: WiMAX Applications.
1 Cellular Application
The main merit of WiMAX is in the area of mobile service. For a large number
of cell phone operators the major monthly operating expense on T1 backhaul
that supports their base stations as shown in Figure 2. A WiMAX substitute
for the cell phone infrastructure could be operated with as little as 10% of T1
backhaul. While replacing a cell phone infrastructure with WiMAX one can
send a large amount of data because the bandwidth of WiMAX is far greater.
The data can include voice, mobile data, TV, videoconferencing, video on
demand, etc.
Figure 2: Cellular architecture using T1 as back haul.
2 WiMAX Military Applications
As WiMAX uses higher frequencies than current military and commercial communications, existing antenna towers share a WiMAX cell tower without compromising the current communication services. WiMAX can be used to support training and war game simulations. An initial deployment of WiMAX has already been constructed by the U.S. Army Fortdix. The U.S. army is testing prestandard WiMAX gear and Xacta secure wireless system from Telos Corporation in Fort Carson in Colorado for point-to-point and point-to-multipoint communications.
The forces at different locations can be connected through WiMAX as shown in Figure 3. They can exchange their information from multiple sources, rapidly and flexibly. This is ideally suited to meet the demands of the tactical defense operations model. The mobile antennas can be attached to a vehicle and the latest data can be provided to the soldiers. A communication from command centers can be made to the different centers, regardless of the distance, and directions can be delivered to the army people. The best part of WiMAX is the handover strategy. It uses “make-before-break’’ sequence rather than “break-before-make’’ sequence.
Figure 3: WiMAX architecture for Military Applications.
3 Medical Applications
In an emergency situation where patients require immediate medical support,
WiMAX can serve as the foundation of a mobile hospital. It can be a platform
for e-health. In e-health services a doctor can diagnose his patient at some
far location with the help of e-media. The doctor ’s computer equipped with the medical instruments can be connected to the patient’s computer through WiMAX.
A patient at location 2 can send his reports, for example, blood pressure, through his computer to the doctor ’s computer as shown in Figure 4. The doctor can diagnose the patient’s disease and give him necessary treatment. The connection between the doctor and the patient is through the Internet. The two computers are connected through WiMAX.
Figure 4: Medical Applications.
Also in some emergency situations, a video consultation with a doctor can be set up and the doctor can instruct the paramedic to mobilize the victim without inflicting further damage. With WiMAX, mobile hospital vans can communicate data and other instructions within a disaster zone. The information through WiMAX can be encrypted and made secure. So in diverse conditions WiMAX can provide to the patient valuable information recommended by doctors over large distances.
4 Security Systems
WiMAX offers a simple and convenient system for security on the borders and within the country to save the nation from some terrorist attacks.
A video camera can be mounted on WiMAX antenna or some separate pole, which can be controlled at the headquarters as shown in Figure 5. This camera will keep an eye over the different activities of the enemies thereby assisting in security planning. It can also be used to provide video surveillance of smuggling and illegal entries along the borders.
WiMAX is a medium for the security of not only army but also navy.
Through the use of WiMAX one can monitor the activities on the sea. A video
camera that is mounted on the antenna of a shipyard can monitor the nearby
activities and report to the headquarter as shown in Figure 5. So WiMAX
can effectively monitor shipyards, nuclear facilities, and key transport routes.
Figure 5: WiMAX architecture for security applications.
5 Disaster Applications
WiMAX can be used in recovery from disasters, such as earthquakes and floods, when the wired networks break down. It helps in connecting the disaster location to telephone services, hospitals, and other important services. In recent hurrican disasters, WiMAX networks were installed to help recovery missions. WiMAX can enable efficient communications with emergency operation centers regardless of the distance. Similarly, WiMAX is used as backup links for broken wired links.
6 Connectivity of Banking Networks
The banking system where security is the major concern can be connected
through the WiMAX networks. Owing to the broad coverage and large con-
nectivity, WiMAX can connect a large number of diversely located banks and
ATM locations. WiMAX networks provide not only
security but also a high degree of scalability. Through WiMAX, telephone
voice, financial transactions, email, Internet, intranet, surveillance, and close
circuit television (CCTV) type of data can be communicated easily.
7 Public Safety
Through WiMAX, public safety agencies can be connected with each other. During any mishap, such as accident, fire, etc., the control office can send its command to the police station, hospital, or fire brigade office. The corresponding agencies immediately can connect to the accidental location by using WiMAX-enabled vehicles.
The video images and data from the site of accidental location can be sent to corresponding agencies. These data can be examined by the experts of the emergency staff and accordingly prescription can be communicated. A video camera in the ambulance can send the latest images of the patient before the ambulance reaches the hospital so that the doctors can get ready for further action quickly. Through WiMAX, a fireman can download the data about the best route to a fire scene.
8 Campus Connectivity
Campus system requires high data capacity, a large coverage, and high
security. WiMAX can connect various blocks within the campus.
Through this connectivity voice, data, and video information can be sent to
various interconnecting blocks as shown in Figure 6. It is very difficult to
connect various blocks through cables because the lead time to deploy a wired
solution is much longer than the lead time to deploy a WiMAX solution.
Figure 6: WiMAX campus connectivity.
9 Educational Building Connectivity
WiMAX can connect boards, colleges, schools, and the main head offices as shown in Figure 7. Through this, telephone voice, data, email, Internet, question papers, intranet, video lectures, presentations, and students’ results can be communicated at a very high rate.
By video conferencing the students can interact with the teachers of another institution (i.e., engineering college, medical colleges, etc.) like as Figure 7. A camera at college 1 delivers real-time classroom instruction to college 2, allowing the colleges to simultaneously deliver instruction from a recognized subject matter expert to a large
Figure 7: WiMAX educational building connectivity.
number of students. Colleges and schools in rural areas can be connected through WiMAX with other institutions having better facilities through WiMAX so that remotely located students can also be benefitted.
Hence it can be concluded that this broadband wireless standard supports
both the computer and telecom industries worldwide, making this technology
highly cost effective. It helps enterprises, consumers, public services, and peo-
ple in urban and rural areas over a large range with high data throughput.
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