The proliferation of mobile computing devices including laptops, personal digital assistants (PDAs),and wearable computers has created a demand for wireless personal area networks (PANs).PANs allow proximal devices to share
information and resources.The mobile nature of these devices places unique requirements on PANs,such as low power consumption, frequent make-and-break connections, resource discovery and utilization, and international regulations.
This paper examines wireless technologies appropriate for PANs and reviews promising research in resource discovery and service utilization. We recognize the need for PDAs to be as manageable as mobile phones and also the restrictive screen area and input area in mobile phone. Thus the need for a new breed of computing devices to fit the bill for a PAN. The above devices become especially relevant for mobile users such as surgeons and jet plane mechanics who need both hands free and thus would need to have "wearable" computers.
This paper first examines the technology used for wireless communication.Putting a radio in a digital device provides physical connectivity;however,to make the device useful in a larger context a networking infrastructure is required. The
infrastructure allows devices o share data,applications,and resources such as printers, mass storage, and computation power. Defining a radio standard is a tractable problem as demonstrated by the solutions presented in this paper.
Designing a network infrastructure is much more complex.
The second half of the paper describes several research projects that try to address components of the networking infrastructure. Finally there are the questions that go beyond the scope of this paper, yet will have he greatest effect on the direction,capabilities,and future of this paradigm. Will these networking strategies be incompatible, like he various cellular phone systems in the United States, or will there be a standard upon which manufacturers and developers agree, like the GSM (global system for mobile communication)cellular phones in Europe?
Communication demands compatibility, which is challenging in a heterogeneous marketplace. Yet by establishing and implementing compatible systems, manufacturers can offer more powerful and useful devices to their customers. Since these are, after all, digital devices living in a programmed digital
world, compatibility and interoperation are possible.
1. Electric field- use human body as a current conduit.
2.Magnetic field-use base station technology for picocells of space.
3.Infra Red- Basic issues including opaque body obstruction.
4.Wireless Radio Frequency- The best technology option however has to deal with the finite resource of the electro magnetic spectrum.
Also must meet international standards by a compatible protocol.
a. UHF Radio.
b. Super regenerative receiver
c. SAW/ASH Receiver.